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1da177e4 LT |
1 | /* |
2 | * This file implements the perfmon-2 subsystem which is used | |
3 | * to program the IA-64 Performance Monitoring Unit (PMU). | |
4 | * | |
5 | * The initial version of perfmon.c was written by | |
6 | * Ganesh Venkitachalam, IBM Corp. | |
7 | * | |
8 | * Then it was modified for perfmon-1.x by Stephane Eranian and | |
9 | * David Mosberger, Hewlett Packard Co. | |
10 | * | |
11 | * Version Perfmon-2.x is a rewrite of perfmon-1.x | |
12 | * by Stephane Eranian, Hewlett Packard Co. | |
13 | * | |
a1ecf7f6 | 14 | * Copyright (C) 1999-2005 Hewlett Packard Co |
1da177e4 LT |
15 | * Stephane Eranian <eranian@hpl.hp.com> |
16 | * David Mosberger-Tang <davidm@hpl.hp.com> | |
17 | * | |
18 | * More information about perfmon available at: | |
19 | * http://www.hpl.hp.com/research/linux/perfmon | |
20 | */ | |
21 | ||
1da177e4 LT |
22 | #include <linux/module.h> |
23 | #include <linux/kernel.h> | |
24 | #include <linux/sched.h> | |
25 | #include <linux/interrupt.h> | |
1da177e4 LT |
26 | #include <linux/proc_fs.h> |
27 | #include <linux/seq_file.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/vmalloc.h> | |
30 | #include <linux/mm.h> | |
31 | #include <linux/sysctl.h> | |
32 | #include <linux/list.h> | |
33 | #include <linux/file.h> | |
34 | #include <linux/poll.h> | |
35 | #include <linux/vfs.h> | |
a3bc0dbc | 36 | #include <linux/smp.h> |
1da177e4 LT |
37 | #include <linux/pagemap.h> |
38 | #include <linux/mount.h> | |
1da177e4 | 39 | #include <linux/bitops.h> |
a9415644 | 40 | #include <linux/capability.h> |
badf1662 | 41 | #include <linux/rcupdate.h> |
60f1c444 | 42 | #include <linux/completion.h> |
f14488cc | 43 | #include <linux/tracehook.h> |
5a0e3ad6 | 44 | #include <linux/slab.h> |
91d591c3 | 45 | #include <linux/cpu.h> |
1da177e4 LT |
46 | |
47 | #include <asm/errno.h> | |
48 | #include <asm/intrinsics.h> | |
49 | #include <asm/page.h> | |
50 | #include <asm/perfmon.h> | |
51 | #include <asm/processor.h> | |
52 | #include <asm/signal.h> | |
1da177e4 LT |
53 | #include <asm/uaccess.h> |
54 | #include <asm/delay.h> | |
55 | ||
56 | #ifdef CONFIG_PERFMON | |
57 | /* | |
58 | * perfmon context state | |
59 | */ | |
60 | #define PFM_CTX_UNLOADED 1 /* context is not loaded onto any task */ | |
61 | #define PFM_CTX_LOADED 2 /* context is loaded onto a task */ | |
62 | #define PFM_CTX_MASKED 3 /* context is loaded but monitoring is masked due to overflow */ | |
63 | #define PFM_CTX_ZOMBIE 4 /* owner of the context is closing it */ | |
64 | ||
65 | #define PFM_INVALID_ACTIVATION (~0UL) | |
66 | ||
35589a8f KA |
67 | #define PFM_NUM_PMC_REGS 64 /* PMC save area for ctxsw */ |
68 | #define PFM_NUM_PMD_REGS 64 /* PMD save area for ctxsw */ | |
69 | ||
1da177e4 LT |
70 | /* |
71 | * depth of message queue | |
72 | */ | |
73 | #define PFM_MAX_MSGS 32 | |
74 | #define PFM_CTXQ_EMPTY(g) ((g)->ctx_msgq_head == (g)->ctx_msgq_tail) | |
75 | ||
76 | /* | |
77 | * type of a PMU register (bitmask). | |
78 | * bitmask structure: | |
79 | * bit0 : register implemented | |
80 | * bit1 : end marker | |
81 | * bit2-3 : reserved | |
82 | * bit4 : pmc has pmc.pm | |
83 | * bit5 : pmc controls a counter (has pmc.oi), pmd is used as counter | |
84 | * bit6-7 : register type | |
85 | * bit8-31: reserved | |
86 | */ | |
87 | #define PFM_REG_NOTIMPL 0x0 /* not implemented at all */ | |
88 | #define PFM_REG_IMPL 0x1 /* register implemented */ | |
89 | #define PFM_REG_END 0x2 /* end marker */ | |
90 | #define PFM_REG_MONITOR (0x1<<4|PFM_REG_IMPL) /* a PMC with a pmc.pm field only */ | |
91 | #define PFM_REG_COUNTING (0x2<<4|PFM_REG_MONITOR) /* a monitor + pmc.oi+ PMD used as a counter */ | |
92 | #define PFM_REG_CONTROL (0x4<<4|PFM_REG_IMPL) /* PMU control register */ | |
93 | #define PFM_REG_CONFIG (0x8<<4|PFM_REG_IMPL) /* configuration register */ | |
94 | #define PFM_REG_BUFFER (0xc<<4|PFM_REG_IMPL) /* PMD used as buffer */ | |
95 | ||
96 | #define PMC_IS_LAST(i) (pmu_conf->pmc_desc[i].type & PFM_REG_END) | |
97 | #define PMD_IS_LAST(i) (pmu_conf->pmd_desc[i].type & PFM_REG_END) | |
98 | ||
99 | #define PMC_OVFL_NOTIFY(ctx, i) ((ctx)->ctx_pmds[i].flags & PFM_REGFL_OVFL_NOTIFY) | |
100 | ||
101 | /* i assumed unsigned */ | |
102 | #define PMC_IS_IMPL(i) (i< PMU_MAX_PMCS && (pmu_conf->pmc_desc[i].type & PFM_REG_IMPL)) | |
103 | #define PMD_IS_IMPL(i) (i< PMU_MAX_PMDS && (pmu_conf->pmd_desc[i].type & PFM_REG_IMPL)) | |
104 | ||
105 | /* XXX: these assume that register i is implemented */ | |
106 | #define PMD_IS_COUNTING(i) ((pmu_conf->pmd_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING) | |
107 | #define PMC_IS_COUNTING(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING) | |
108 | #define PMC_IS_MONITOR(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_MONITOR) == PFM_REG_MONITOR) | |
109 | #define PMC_IS_CONTROL(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_CONTROL) == PFM_REG_CONTROL) | |
110 | ||
111 | #define PMC_DFL_VAL(i) pmu_conf->pmc_desc[i].default_value | |
112 | #define PMC_RSVD_MASK(i) pmu_conf->pmc_desc[i].reserved_mask | |
113 | #define PMD_PMD_DEP(i) pmu_conf->pmd_desc[i].dep_pmd[0] | |
114 | #define PMC_PMD_DEP(i) pmu_conf->pmc_desc[i].dep_pmd[0] | |
115 | ||
116 | #define PFM_NUM_IBRS IA64_NUM_DBG_REGS | |
117 | #define PFM_NUM_DBRS IA64_NUM_DBG_REGS | |
118 | ||
119 | #define CTX_OVFL_NOBLOCK(c) ((c)->ctx_fl_block == 0) | |
120 | #define CTX_HAS_SMPL(c) ((c)->ctx_fl_is_sampling) | |
121 | #define PFM_CTX_TASK(h) (h)->ctx_task | |
122 | ||
123 | #define PMU_PMC_OI 5 /* position of pmc.oi bit */ | |
124 | ||
125 | /* XXX: does not support more than 64 PMDs */ | |
126 | #define CTX_USED_PMD(ctx, mask) (ctx)->ctx_used_pmds[0] |= (mask) | |
127 | #define CTX_IS_USED_PMD(ctx, c) (((ctx)->ctx_used_pmds[0] & (1UL << (c))) != 0UL) | |
128 | ||
129 | #define CTX_USED_MONITOR(ctx, mask) (ctx)->ctx_used_monitors[0] |= (mask) | |
130 | ||
131 | #define CTX_USED_IBR(ctx,n) (ctx)->ctx_used_ibrs[(n)>>6] |= 1UL<< ((n) % 64) | |
132 | #define CTX_USED_DBR(ctx,n) (ctx)->ctx_used_dbrs[(n)>>6] |= 1UL<< ((n) % 64) | |
133 | #define CTX_USES_DBREGS(ctx) (((pfm_context_t *)(ctx))->ctx_fl_using_dbreg==1) | |
134 | #define PFM_CODE_RR 0 /* requesting code range restriction */ | |
135 | #define PFM_DATA_RR 1 /* requestion data range restriction */ | |
136 | ||
137 | #define PFM_CPUINFO_CLEAR(v) pfm_get_cpu_var(pfm_syst_info) &= ~(v) | |
138 | #define PFM_CPUINFO_SET(v) pfm_get_cpu_var(pfm_syst_info) |= (v) | |
139 | #define PFM_CPUINFO_GET() pfm_get_cpu_var(pfm_syst_info) | |
140 | ||
141 | #define RDEP(x) (1UL<<(x)) | |
142 | ||
143 | /* | |
144 | * context protection macros | |
145 | * in SMP: | |
146 | * - we need to protect against CPU concurrency (spin_lock) | |
147 | * - we need to protect against PMU overflow interrupts (local_irq_disable) | |
148 | * in UP: | |
149 | * - we need to protect against PMU overflow interrupts (local_irq_disable) | |
150 | * | |
85d1fe09 | 151 | * spin_lock_irqsave()/spin_unlock_irqrestore(): |
1da177e4 LT |
152 | * in SMP: local_irq_disable + spin_lock |
153 | * in UP : local_irq_disable | |
154 | * | |
155 | * spin_lock()/spin_lock(): | |
156 | * in UP : removed automatically | |
157 | * in SMP: protect against context accesses from other CPU. interrupts | |
158 | * are not masked. This is useful for the PMU interrupt handler | |
159 | * because we know we will not get PMU concurrency in that code. | |
160 | */ | |
161 | #define PROTECT_CTX(c, f) \ | |
162 | do { \ | |
19c5870c | 163 | DPRINT(("spinlock_irq_save ctx %p by [%d]\n", c, task_pid_nr(current))); \ |
1da177e4 | 164 | spin_lock_irqsave(&(c)->ctx_lock, f); \ |
19c5870c | 165 | DPRINT(("spinlocked ctx %p by [%d]\n", c, task_pid_nr(current))); \ |
1da177e4 LT |
166 | } while(0) |
167 | ||
168 | #define UNPROTECT_CTX(c, f) \ | |
169 | do { \ | |
19c5870c | 170 | DPRINT(("spinlock_irq_restore ctx %p by [%d]\n", c, task_pid_nr(current))); \ |
1da177e4 LT |
171 | spin_unlock_irqrestore(&(c)->ctx_lock, f); \ |
172 | } while(0) | |
173 | ||
174 | #define PROTECT_CTX_NOPRINT(c, f) \ | |
175 | do { \ | |
176 | spin_lock_irqsave(&(c)->ctx_lock, f); \ | |
177 | } while(0) | |
178 | ||
179 | ||
180 | #define UNPROTECT_CTX_NOPRINT(c, f) \ | |
181 | do { \ | |
182 | spin_unlock_irqrestore(&(c)->ctx_lock, f); \ | |
183 | } while(0) | |
184 | ||
185 | ||
186 | #define PROTECT_CTX_NOIRQ(c) \ | |
187 | do { \ | |
188 | spin_lock(&(c)->ctx_lock); \ | |
189 | } while(0) | |
190 | ||
191 | #define UNPROTECT_CTX_NOIRQ(c) \ | |
192 | do { \ | |
193 | spin_unlock(&(c)->ctx_lock); \ | |
194 | } while(0) | |
195 | ||
196 | ||
197 | #ifdef CONFIG_SMP | |
198 | ||
199 | #define GET_ACTIVATION() pfm_get_cpu_var(pmu_activation_number) | |
200 | #define INC_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)++ | |
201 | #define SET_ACTIVATION(c) (c)->ctx_last_activation = GET_ACTIVATION() | |
202 | ||
203 | #else /* !CONFIG_SMP */ | |
204 | #define SET_ACTIVATION(t) do {} while(0) | |
205 | #define GET_ACTIVATION(t) do {} while(0) | |
206 | #define INC_ACTIVATION(t) do {} while(0) | |
207 | #endif /* CONFIG_SMP */ | |
208 | ||
209 | #define SET_PMU_OWNER(t, c) do { pfm_get_cpu_var(pmu_owner) = (t); pfm_get_cpu_var(pmu_ctx) = (c); } while(0) | |
210 | #define GET_PMU_OWNER() pfm_get_cpu_var(pmu_owner) | |
211 | #define GET_PMU_CTX() pfm_get_cpu_var(pmu_ctx) | |
212 | ||
213 | #define LOCK_PFS(g) spin_lock_irqsave(&pfm_sessions.pfs_lock, g) | |
214 | #define UNLOCK_PFS(g) spin_unlock_irqrestore(&pfm_sessions.pfs_lock, g) | |
215 | ||
216 | #define PFM_REG_RETFLAG_SET(flags, val) do { flags &= ~PFM_REG_RETFL_MASK; flags |= (val); } while(0) | |
217 | ||
218 | /* | |
219 | * cmp0 must be the value of pmc0 | |
220 | */ | |
221 | #define PMC0_HAS_OVFL(cmp0) (cmp0 & ~0x1UL) | |
222 | ||
223 | #define PFMFS_MAGIC 0xa0b4d889 | |
224 | ||
225 | /* | |
226 | * debugging | |
227 | */ | |
228 | #define PFM_DEBUGGING 1 | |
229 | #ifdef PFM_DEBUGGING | |
230 | #define DPRINT(a) \ | |
231 | do { \ | |
d4ed8084 | 232 | if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d [%d] ", __func__, __LINE__, smp_processor_id(), task_pid_nr(current)); printk a; } \ |
1da177e4 LT |
233 | } while (0) |
234 | ||
235 | #define DPRINT_ovfl(a) \ | |
236 | do { \ | |
d4ed8084 | 237 | if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d [%d] ", __func__, __LINE__, smp_processor_id(), task_pid_nr(current)); printk a; } \ |
1da177e4 LT |
238 | } while (0) |
239 | #endif | |
240 | ||
241 | /* | |
242 | * 64-bit software counter structure | |
243 | * | |
244 | * the next_reset_type is applied to the next call to pfm_reset_regs() | |
245 | */ | |
246 | typedef struct { | |
247 | unsigned long val; /* virtual 64bit counter value */ | |
248 | unsigned long lval; /* last reset value */ | |
249 | unsigned long long_reset; /* reset value on sampling overflow */ | |
250 | unsigned long short_reset; /* reset value on overflow */ | |
251 | unsigned long reset_pmds[4]; /* which other pmds to reset when this counter overflows */ | |
252 | unsigned long smpl_pmds[4]; /* which pmds are accessed when counter overflow */ | |
253 | unsigned long seed; /* seed for random-number generator */ | |
254 | unsigned long mask; /* mask for random-number generator */ | |
255 | unsigned int flags; /* notify/do not notify */ | |
256 | unsigned long eventid; /* overflow event identifier */ | |
257 | } pfm_counter_t; | |
258 | ||
259 | /* | |
260 | * context flags | |
261 | */ | |
262 | typedef struct { | |
263 | unsigned int block:1; /* when 1, task will blocked on user notifications */ | |
264 | unsigned int system:1; /* do system wide monitoring */ | |
265 | unsigned int using_dbreg:1; /* using range restrictions (debug registers) */ | |
266 | unsigned int is_sampling:1; /* true if using a custom format */ | |
267 | unsigned int excl_idle:1; /* exclude idle task in system wide session */ | |
268 | unsigned int going_zombie:1; /* context is zombie (MASKED+blocking) */ | |
269 | unsigned int trap_reason:2; /* reason for going into pfm_handle_work() */ | |
270 | unsigned int no_msg:1; /* no message sent on overflow */ | |
271 | unsigned int can_restart:1; /* allowed to issue a PFM_RESTART */ | |
272 | unsigned int reserved:22; | |
273 | } pfm_context_flags_t; | |
274 | ||
275 | #define PFM_TRAP_REASON_NONE 0x0 /* default value */ | |
276 | #define PFM_TRAP_REASON_BLOCK 0x1 /* we need to block on overflow */ | |
277 | #define PFM_TRAP_REASON_RESET 0x2 /* we need to reset PMDs */ | |
278 | ||
279 | ||
280 | /* | |
281 | * perfmon context: encapsulates all the state of a monitoring session | |
282 | */ | |
283 | ||
284 | typedef struct pfm_context { | |
285 | spinlock_t ctx_lock; /* context protection */ | |
286 | ||
287 | pfm_context_flags_t ctx_flags; /* bitmask of flags (block reason incl.) */ | |
288 | unsigned int ctx_state; /* state: active/inactive (no bitfield) */ | |
289 | ||
290 | struct task_struct *ctx_task; /* task to which context is attached */ | |
291 | ||
292 | unsigned long ctx_ovfl_regs[4]; /* which registers overflowed (notification) */ | |
293 | ||
60f1c444 | 294 | struct completion ctx_restart_done; /* use for blocking notification mode */ |
1da177e4 LT |
295 | |
296 | unsigned long ctx_used_pmds[4]; /* bitmask of PMD used */ | |
297 | unsigned long ctx_all_pmds[4]; /* bitmask of all accessible PMDs */ | |
298 | unsigned long ctx_reload_pmds[4]; /* bitmask of force reload PMD on ctxsw in */ | |
299 | ||
300 | unsigned long ctx_all_pmcs[4]; /* bitmask of all accessible PMCs */ | |
301 | unsigned long ctx_reload_pmcs[4]; /* bitmask of force reload PMC on ctxsw in */ | |
302 | unsigned long ctx_used_monitors[4]; /* bitmask of monitor PMC being used */ | |
303 | ||
35589a8f | 304 | unsigned long ctx_pmcs[PFM_NUM_PMC_REGS]; /* saved copies of PMC values */ |
1da177e4 LT |
305 | |
306 | unsigned int ctx_used_ibrs[1]; /* bitmask of used IBR (speedup ctxsw in) */ | |
307 | unsigned int ctx_used_dbrs[1]; /* bitmask of used DBR (speedup ctxsw in) */ | |
308 | unsigned long ctx_dbrs[IA64_NUM_DBG_REGS]; /* DBR values (cache) when not loaded */ | |
309 | unsigned long ctx_ibrs[IA64_NUM_DBG_REGS]; /* IBR values (cache) when not loaded */ | |
310 | ||
35589a8f KA |
311 | pfm_counter_t ctx_pmds[PFM_NUM_PMD_REGS]; /* software state for PMDS */ |
312 | ||
313 | unsigned long th_pmcs[PFM_NUM_PMC_REGS]; /* PMC thread save state */ | |
314 | unsigned long th_pmds[PFM_NUM_PMD_REGS]; /* PMD thread save state */ | |
1da177e4 | 315 | |
e088a4ad | 316 | unsigned long ctx_saved_psr_up; /* only contains psr.up value */ |
1da177e4 LT |
317 | |
318 | unsigned long ctx_last_activation; /* context last activation number for last_cpu */ | |
319 | unsigned int ctx_last_cpu; /* CPU id of current or last CPU used (SMP only) */ | |
320 | unsigned int ctx_cpu; /* cpu to which perfmon is applied (system wide) */ | |
321 | ||
322 | int ctx_fd; /* file descriptor used my this context */ | |
323 | pfm_ovfl_arg_t ctx_ovfl_arg; /* argument to custom buffer format handler */ | |
324 | ||
325 | pfm_buffer_fmt_t *ctx_buf_fmt; /* buffer format callbacks */ | |
326 | void *ctx_smpl_hdr; /* points to sampling buffer header kernel vaddr */ | |
327 | unsigned long ctx_smpl_size; /* size of sampling buffer */ | |
328 | void *ctx_smpl_vaddr; /* user level virtual address of smpl buffer */ | |
329 | ||
330 | wait_queue_head_t ctx_msgq_wait; | |
331 | pfm_msg_t ctx_msgq[PFM_MAX_MSGS]; | |
332 | int ctx_msgq_head; | |
333 | int ctx_msgq_tail; | |
334 | struct fasync_struct *ctx_async_queue; | |
335 | ||
336 | wait_queue_head_t ctx_zombieq; /* termination cleanup wait queue */ | |
337 | } pfm_context_t; | |
338 | ||
339 | /* | |
340 | * magic number used to verify that structure is really | |
341 | * a perfmon context | |
342 | */ | |
343 | #define PFM_IS_FILE(f) ((f)->f_op == &pfm_file_ops) | |
344 | ||
345 | #define PFM_GET_CTX(t) ((pfm_context_t *)(t)->thread.pfm_context) | |
346 | ||
347 | #ifdef CONFIG_SMP | |
348 | #define SET_LAST_CPU(ctx, v) (ctx)->ctx_last_cpu = (v) | |
349 | #define GET_LAST_CPU(ctx) (ctx)->ctx_last_cpu | |
350 | #else | |
351 | #define SET_LAST_CPU(ctx, v) do {} while(0) | |
352 | #define GET_LAST_CPU(ctx) do {} while(0) | |
353 | #endif | |
354 | ||
355 | ||
356 | #define ctx_fl_block ctx_flags.block | |
357 | #define ctx_fl_system ctx_flags.system | |
358 | #define ctx_fl_using_dbreg ctx_flags.using_dbreg | |
359 | #define ctx_fl_is_sampling ctx_flags.is_sampling | |
360 | #define ctx_fl_excl_idle ctx_flags.excl_idle | |
361 | #define ctx_fl_going_zombie ctx_flags.going_zombie | |
362 | #define ctx_fl_trap_reason ctx_flags.trap_reason | |
363 | #define ctx_fl_no_msg ctx_flags.no_msg | |
364 | #define ctx_fl_can_restart ctx_flags.can_restart | |
365 | ||
366 | #define PFM_SET_WORK_PENDING(t, v) do { (t)->thread.pfm_needs_checking = v; } while(0); | |
367 | #define PFM_GET_WORK_PENDING(t) (t)->thread.pfm_needs_checking | |
368 | ||
369 | /* | |
370 | * global information about all sessions | |
371 | * mostly used to synchronize between system wide and per-process | |
372 | */ | |
373 | typedef struct { | |
374 | spinlock_t pfs_lock; /* lock the structure */ | |
375 | ||
376 | unsigned int pfs_task_sessions; /* number of per task sessions */ | |
377 | unsigned int pfs_sys_sessions; /* number of per system wide sessions */ | |
378 | unsigned int pfs_sys_use_dbregs; /* incremented when a system wide session uses debug regs */ | |
379 | unsigned int pfs_ptrace_use_dbregs; /* incremented when a process uses debug regs */ | |
380 | struct task_struct *pfs_sys_session[NR_CPUS]; /* point to task owning a system-wide session */ | |
381 | } pfm_session_t; | |
382 | ||
383 | /* | |
384 | * information about a PMC or PMD. | |
385 | * dep_pmd[]: a bitmask of dependent PMD registers | |
386 | * dep_pmc[]: a bitmask of dependent PMC registers | |
387 | */ | |
388 | typedef int (*pfm_reg_check_t)(struct task_struct *task, pfm_context_t *ctx, unsigned int cnum, unsigned long *val, struct pt_regs *regs); | |
389 | typedef struct { | |
390 | unsigned int type; | |
391 | int pm_pos; | |
392 | unsigned long default_value; /* power-on default value */ | |
393 | unsigned long reserved_mask; /* bitmask of reserved bits */ | |
394 | pfm_reg_check_t read_check; | |
395 | pfm_reg_check_t write_check; | |
396 | unsigned long dep_pmd[4]; | |
397 | unsigned long dep_pmc[4]; | |
398 | } pfm_reg_desc_t; | |
399 | ||
400 | /* assume cnum is a valid monitor */ | |
401 | #define PMC_PM(cnum, val) (((val) >> (pmu_conf->pmc_desc[cnum].pm_pos)) & 0x1) | |
402 | ||
403 | /* | |
404 | * This structure is initialized at boot time and contains | |
405 | * a description of the PMU main characteristics. | |
406 | * | |
407 | * If the probe function is defined, detection is based | |
408 | * on its return value: | |
409 | * - 0 means recognized PMU | |
410 | * - anything else means not supported | |
411 | * When the probe function is not defined, then the pmu_family field | |
412 | * is used and it must match the host CPU family such that: | |
413 | * - cpu->family & config->pmu_family != 0 | |
414 | */ | |
415 | typedef struct { | |
416 | unsigned long ovfl_val; /* overflow value for counters */ | |
417 | ||
418 | pfm_reg_desc_t *pmc_desc; /* detailed PMC register dependencies descriptions */ | |
419 | pfm_reg_desc_t *pmd_desc; /* detailed PMD register dependencies descriptions */ | |
420 | ||
421 | unsigned int num_pmcs; /* number of PMCS: computed at init time */ | |
422 | unsigned int num_pmds; /* number of PMDS: computed at init time */ | |
423 | unsigned long impl_pmcs[4]; /* bitmask of implemented PMCS */ | |
424 | unsigned long impl_pmds[4]; /* bitmask of implemented PMDS */ | |
425 | ||
426 | char *pmu_name; /* PMU family name */ | |
427 | unsigned int pmu_family; /* cpuid family pattern used to identify pmu */ | |
428 | unsigned int flags; /* pmu specific flags */ | |
429 | unsigned int num_ibrs; /* number of IBRS: computed at init time */ | |
430 | unsigned int num_dbrs; /* number of DBRS: computed at init time */ | |
431 | unsigned int num_counters; /* PMC/PMD counting pairs : computed at init time */ | |
432 | int (*probe)(void); /* customized probe routine */ | |
433 | unsigned int use_rr_dbregs:1; /* set if debug registers used for range restriction */ | |
434 | } pmu_config_t; | |
435 | /* | |
436 | * PMU specific flags | |
437 | */ | |
438 | #define PFM_PMU_IRQ_RESEND 1 /* PMU needs explicit IRQ resend */ | |
439 | ||
440 | /* | |
441 | * debug register related type definitions | |
442 | */ | |
443 | typedef struct { | |
444 | unsigned long ibr_mask:56; | |
445 | unsigned long ibr_plm:4; | |
446 | unsigned long ibr_ig:3; | |
447 | unsigned long ibr_x:1; | |
448 | } ibr_mask_reg_t; | |
449 | ||
450 | typedef struct { | |
451 | unsigned long dbr_mask:56; | |
452 | unsigned long dbr_plm:4; | |
453 | unsigned long dbr_ig:2; | |
454 | unsigned long dbr_w:1; | |
455 | unsigned long dbr_r:1; | |
456 | } dbr_mask_reg_t; | |
457 | ||
458 | typedef union { | |
459 | unsigned long val; | |
460 | ibr_mask_reg_t ibr; | |
461 | dbr_mask_reg_t dbr; | |
462 | } dbreg_t; | |
463 | ||
464 | ||
465 | /* | |
466 | * perfmon command descriptions | |
467 | */ | |
468 | typedef struct { | |
469 | int (*cmd_func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); | |
470 | char *cmd_name; | |
471 | int cmd_flags; | |
472 | unsigned int cmd_narg; | |
473 | size_t cmd_argsize; | |
474 | int (*cmd_getsize)(void *arg, size_t *sz); | |
475 | } pfm_cmd_desc_t; | |
476 | ||
477 | #define PFM_CMD_FD 0x01 /* command requires a file descriptor */ | |
478 | #define PFM_CMD_ARG_READ 0x02 /* command must read argument(s) */ | |
479 | #define PFM_CMD_ARG_RW 0x04 /* command must read/write argument(s) */ | |
480 | #define PFM_CMD_STOP 0x08 /* command does not work on zombie context */ | |
481 | ||
482 | ||
483 | #define PFM_CMD_NAME(cmd) pfm_cmd_tab[(cmd)].cmd_name | |
484 | #define PFM_CMD_READ_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_READ) | |
485 | #define PFM_CMD_RW_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_RW) | |
486 | #define PFM_CMD_USE_FD(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_FD) | |
487 | #define PFM_CMD_STOPPED(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_STOP) | |
488 | ||
489 | #define PFM_CMD_ARG_MANY -1 /* cannot be zero */ | |
490 | ||
1da177e4 LT |
491 | typedef struct { |
492 | unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */ | |
493 | unsigned long pfm_replay_ovfl_intr_count; /* keep track of replayed ovfl interrupts */ | |
494 | unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */ | |
495 | unsigned long pfm_ovfl_intr_cycles; /* cycles spent processing ovfl interrupts */ | |
496 | unsigned long pfm_ovfl_intr_cycles_min; /* min cycles spent processing ovfl interrupts */ | |
497 | unsigned long pfm_ovfl_intr_cycles_max; /* max cycles spent processing ovfl interrupts */ | |
498 | unsigned long pfm_smpl_handler_calls; | |
499 | unsigned long pfm_smpl_handler_cycles; | |
500 | char pad[SMP_CACHE_BYTES] ____cacheline_aligned; | |
501 | } pfm_stats_t; | |
502 | ||
503 | /* | |
504 | * perfmon internal variables | |
505 | */ | |
506 | static pfm_stats_t pfm_stats[NR_CPUS]; | |
507 | static pfm_session_t pfm_sessions; /* global sessions information */ | |
508 | ||
a9f6a0dd | 509 | static DEFINE_SPINLOCK(pfm_alt_install_check); |
a1ecf7f6 TL |
510 | static pfm_intr_handler_desc_t *pfm_alt_intr_handler; |
511 | ||
1da177e4 LT |
512 | static struct proc_dir_entry *perfmon_dir; |
513 | static pfm_uuid_t pfm_null_uuid = {0,}; | |
514 | ||
515 | static spinlock_t pfm_buffer_fmt_lock; | |
516 | static LIST_HEAD(pfm_buffer_fmt_list); | |
517 | ||
518 | static pmu_config_t *pmu_conf; | |
519 | ||
520 | /* sysctl() controls */ | |
4944930a SE |
521 | pfm_sysctl_t pfm_sysctl; |
522 | EXPORT_SYMBOL(pfm_sysctl); | |
1da177e4 LT |
523 | |
524 | static ctl_table pfm_ctl_table[]={ | |
4e009901 | 525 | { |
4e009901 EB |
526 | .procname = "debug", |
527 | .data = &pfm_sysctl.debug, | |
528 | .maxlen = sizeof(int), | |
529 | .mode = 0666, | |
6d456111 | 530 | .proc_handler = proc_dointvec, |
4e009901 EB |
531 | }, |
532 | { | |
4e009901 EB |
533 | .procname = "debug_ovfl", |
534 | .data = &pfm_sysctl.debug_ovfl, | |
535 | .maxlen = sizeof(int), | |
536 | .mode = 0666, | |
6d456111 | 537 | .proc_handler = proc_dointvec, |
4e009901 EB |
538 | }, |
539 | { | |
4e009901 EB |
540 | .procname = "fastctxsw", |
541 | .data = &pfm_sysctl.fastctxsw, | |
542 | .maxlen = sizeof(int), | |
543 | .mode = 0600, | |
6d456111 | 544 | .proc_handler = proc_dointvec, |
4e009901 EB |
545 | }, |
546 | { | |
4e009901 EB |
547 | .procname = "expert_mode", |
548 | .data = &pfm_sysctl.expert_mode, | |
549 | .maxlen = sizeof(int), | |
550 | .mode = 0600, | |
6d456111 | 551 | .proc_handler = proc_dointvec, |
4e009901 EB |
552 | }, |
553 | {} | |
1da177e4 LT |
554 | }; |
555 | static ctl_table pfm_sysctl_dir[] = { | |
4e009901 | 556 | { |
4e009901 | 557 | .procname = "perfmon", |
e3ad42be | 558 | .mode = 0555, |
4e009901 EB |
559 | .child = pfm_ctl_table, |
560 | }, | |
561 | {} | |
1da177e4 LT |
562 | }; |
563 | static ctl_table pfm_sysctl_root[] = { | |
4e009901 | 564 | { |
4e009901 | 565 | .procname = "kernel", |
e3ad42be | 566 | .mode = 0555, |
4e009901 EB |
567 | .child = pfm_sysctl_dir, |
568 | }, | |
569 | {} | |
1da177e4 LT |
570 | }; |
571 | static struct ctl_table_header *pfm_sysctl_header; | |
572 | ||
573 | static int pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); | |
1da177e4 LT |
574 | |
575 | #define pfm_get_cpu_var(v) __ia64_per_cpu_var(v) | |
576 | #define pfm_get_cpu_data(a,b) per_cpu(a, b) | |
577 | ||
578 | static inline void | |
579 | pfm_put_task(struct task_struct *task) | |
580 | { | |
581 | if (task != current) put_task_struct(task); | |
582 | } | |
583 | ||
1da177e4 LT |
584 | static inline void |
585 | pfm_reserve_page(unsigned long a) | |
586 | { | |
587 | SetPageReserved(vmalloc_to_page((void *)a)); | |
588 | } | |
589 | static inline void | |
590 | pfm_unreserve_page(unsigned long a) | |
591 | { | |
592 | ClearPageReserved(vmalloc_to_page((void*)a)); | |
593 | } | |
594 | ||
595 | static inline unsigned long | |
596 | pfm_protect_ctx_ctxsw(pfm_context_t *x) | |
597 | { | |
598 | spin_lock(&(x)->ctx_lock); | |
599 | return 0UL; | |
600 | } | |
601 | ||
24b8e0cc | 602 | static inline void |
1da177e4 LT |
603 | pfm_unprotect_ctx_ctxsw(pfm_context_t *x, unsigned long f) |
604 | { | |
605 | spin_unlock(&(x)->ctx_lock); | |
606 | } | |
607 | ||
c74a1cbb | 608 | /* forward declaration */ |
09579770 | 609 | static const struct dentry_operations pfmfs_dentry_operations; |
1da177e4 | 610 | |
51139ada AV |
611 | static struct dentry * |
612 | pfmfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) | |
1da177e4 | 613 | { |
c74a1cbb AV |
614 | return mount_pseudo(fs_type, "pfm:", NULL, &pfmfs_dentry_operations, |
615 | PFMFS_MAGIC); | |
1da177e4 LT |
616 | } |
617 | ||
618 | static struct file_system_type pfm_fs_type = { | |
619 | .name = "pfmfs", | |
51139ada | 620 | .mount = pfmfs_mount, |
1da177e4 LT |
621 | .kill_sb = kill_anon_super, |
622 | }; | |
7f78e035 | 623 | MODULE_ALIAS_FS("pfmfs"); |
1da177e4 LT |
624 | |
625 | DEFINE_PER_CPU(unsigned long, pfm_syst_info); | |
626 | DEFINE_PER_CPU(struct task_struct *, pmu_owner); | |
627 | DEFINE_PER_CPU(pfm_context_t *, pmu_ctx); | |
628 | DEFINE_PER_CPU(unsigned long, pmu_activation_number); | |
fffcc150 | 629 | EXPORT_PER_CPU_SYMBOL_GPL(pfm_syst_info); |
1da177e4 LT |
630 | |
631 | ||
632 | /* forward declaration */ | |
5dfe4c96 | 633 | static const struct file_operations pfm_file_ops; |
1da177e4 LT |
634 | |
635 | /* | |
636 | * forward declarations | |
637 | */ | |
638 | #ifndef CONFIG_SMP | |
639 | static void pfm_lazy_save_regs (struct task_struct *ta); | |
640 | #endif | |
641 | ||
642 | void dump_pmu_state(const char *); | |
643 | static int pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); | |
644 | ||
645 | #include "perfmon_itanium.h" | |
646 | #include "perfmon_mckinley.h" | |
9179cb65 | 647 | #include "perfmon_montecito.h" |
1da177e4 LT |
648 | #include "perfmon_generic.h" |
649 | ||
650 | static pmu_config_t *pmu_confs[]={ | |
9179cb65 | 651 | &pmu_conf_mont, |
1da177e4 LT |
652 | &pmu_conf_mck, |
653 | &pmu_conf_ita, | |
654 | &pmu_conf_gen, /* must be last */ | |
655 | NULL | |
656 | }; | |
657 | ||
658 | ||
659 | static int pfm_end_notify_user(pfm_context_t *ctx); | |
660 | ||
661 | static inline void | |
662 | pfm_clear_psr_pp(void) | |
663 | { | |
664 | ia64_rsm(IA64_PSR_PP); | |
665 | ia64_srlz_i(); | |
666 | } | |
667 | ||
668 | static inline void | |
669 | pfm_set_psr_pp(void) | |
670 | { | |
671 | ia64_ssm(IA64_PSR_PP); | |
672 | ia64_srlz_i(); | |
673 | } | |
674 | ||
675 | static inline void | |
676 | pfm_clear_psr_up(void) | |
677 | { | |
678 | ia64_rsm(IA64_PSR_UP); | |
679 | ia64_srlz_i(); | |
680 | } | |
681 | ||
682 | static inline void | |
683 | pfm_set_psr_up(void) | |
684 | { | |
685 | ia64_ssm(IA64_PSR_UP); | |
686 | ia64_srlz_i(); | |
687 | } | |
688 | ||
689 | static inline unsigned long | |
690 | pfm_get_psr(void) | |
691 | { | |
692 | unsigned long tmp; | |
693 | tmp = ia64_getreg(_IA64_REG_PSR); | |
694 | ia64_srlz_i(); | |
695 | return tmp; | |
696 | } | |
697 | ||
698 | static inline void | |
699 | pfm_set_psr_l(unsigned long val) | |
700 | { | |
701 | ia64_setreg(_IA64_REG_PSR_L, val); | |
702 | ia64_srlz_i(); | |
703 | } | |
704 | ||
705 | static inline void | |
706 | pfm_freeze_pmu(void) | |
707 | { | |
708 | ia64_set_pmc(0,1UL); | |
709 | ia64_srlz_d(); | |
710 | } | |
711 | ||
712 | static inline void | |
713 | pfm_unfreeze_pmu(void) | |
714 | { | |
715 | ia64_set_pmc(0,0UL); | |
716 | ia64_srlz_d(); | |
717 | } | |
718 | ||
719 | static inline void | |
720 | pfm_restore_ibrs(unsigned long *ibrs, unsigned int nibrs) | |
721 | { | |
722 | int i; | |
723 | ||
724 | for (i=0; i < nibrs; i++) { | |
725 | ia64_set_ibr(i, ibrs[i]); | |
726 | ia64_dv_serialize_instruction(); | |
727 | } | |
728 | ia64_srlz_i(); | |
729 | } | |
730 | ||
731 | static inline void | |
732 | pfm_restore_dbrs(unsigned long *dbrs, unsigned int ndbrs) | |
733 | { | |
734 | int i; | |
735 | ||
736 | for (i=0; i < ndbrs; i++) { | |
737 | ia64_set_dbr(i, dbrs[i]); | |
738 | ia64_dv_serialize_data(); | |
739 | } | |
740 | ia64_srlz_d(); | |
741 | } | |
742 | ||
743 | /* | |
744 | * PMD[i] must be a counter. no check is made | |
745 | */ | |
746 | static inline unsigned long | |
747 | pfm_read_soft_counter(pfm_context_t *ctx, int i) | |
748 | { | |
749 | return ctx->ctx_pmds[i].val + (ia64_get_pmd(i) & pmu_conf->ovfl_val); | |
750 | } | |
751 | ||
752 | /* | |
753 | * PMD[i] must be a counter. no check is made | |
754 | */ | |
755 | static inline void | |
756 | pfm_write_soft_counter(pfm_context_t *ctx, int i, unsigned long val) | |
757 | { | |
758 | unsigned long ovfl_val = pmu_conf->ovfl_val; | |
759 | ||
760 | ctx->ctx_pmds[i].val = val & ~ovfl_val; | |
761 | /* | |
762 | * writing to unimplemented part is ignore, so we do not need to | |
763 | * mask off top part | |
764 | */ | |
765 | ia64_set_pmd(i, val & ovfl_val); | |
766 | } | |
767 | ||
768 | static pfm_msg_t * | |
769 | pfm_get_new_msg(pfm_context_t *ctx) | |
770 | { | |
771 | int idx, next; | |
772 | ||
773 | next = (ctx->ctx_msgq_tail+1) % PFM_MAX_MSGS; | |
774 | ||
775 | DPRINT(("ctx_fd=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail)); | |
776 | if (next == ctx->ctx_msgq_head) return NULL; | |
777 | ||
778 | idx = ctx->ctx_msgq_tail; | |
779 | ctx->ctx_msgq_tail = next; | |
780 | ||
781 | DPRINT(("ctx=%p head=%d tail=%d msg=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, idx)); | |
782 | ||
783 | return ctx->ctx_msgq+idx; | |
784 | } | |
785 | ||
786 | static pfm_msg_t * | |
787 | pfm_get_next_msg(pfm_context_t *ctx) | |
788 | { | |
789 | pfm_msg_t *msg; | |
790 | ||
791 | DPRINT(("ctx=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail)); | |
792 | ||
793 | if (PFM_CTXQ_EMPTY(ctx)) return NULL; | |
794 | ||
795 | /* | |
796 | * get oldest message | |
797 | */ | |
798 | msg = ctx->ctx_msgq+ctx->ctx_msgq_head; | |
799 | ||
800 | /* | |
801 | * and move forward | |
802 | */ | |
803 | ctx->ctx_msgq_head = (ctx->ctx_msgq_head+1) % PFM_MAX_MSGS; | |
804 | ||
805 | DPRINT(("ctx=%p head=%d tail=%d type=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, msg->pfm_gen_msg.msg_type)); | |
806 | ||
807 | return msg; | |
808 | } | |
809 | ||
810 | static void | |
811 | pfm_reset_msgq(pfm_context_t *ctx) | |
812 | { | |
813 | ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0; | |
814 | DPRINT(("ctx=%p msgq reset\n", ctx)); | |
815 | } | |
816 | ||
817 | static void * | |
818 | pfm_rvmalloc(unsigned long size) | |
819 | { | |
820 | void *mem; | |
821 | unsigned long addr; | |
822 | ||
823 | size = PAGE_ALIGN(size); | |
e21763db | 824 | mem = vzalloc(size); |
1da177e4 LT |
825 | if (mem) { |
826 | //printk("perfmon: CPU%d pfm_rvmalloc(%ld)=%p\n", smp_processor_id(), size, mem); | |
1da177e4 LT |
827 | addr = (unsigned long)mem; |
828 | while (size > 0) { | |
829 | pfm_reserve_page(addr); | |
830 | addr+=PAGE_SIZE; | |
831 | size-=PAGE_SIZE; | |
832 | } | |
833 | } | |
834 | return mem; | |
835 | } | |
836 | ||
837 | static void | |
838 | pfm_rvfree(void *mem, unsigned long size) | |
839 | { | |
840 | unsigned long addr; | |
841 | ||
842 | if (mem) { | |
843 | DPRINT(("freeing physical buffer @%p size=%lu\n", mem, size)); | |
844 | addr = (unsigned long) mem; | |
845 | while ((long) size > 0) { | |
846 | pfm_unreserve_page(addr); | |
847 | addr+=PAGE_SIZE; | |
848 | size-=PAGE_SIZE; | |
849 | } | |
850 | vfree(mem); | |
851 | } | |
852 | return; | |
853 | } | |
854 | ||
855 | static pfm_context_t * | |
f8e811b9 | 856 | pfm_context_alloc(int ctx_flags) |
1da177e4 LT |
857 | { |
858 | pfm_context_t *ctx; | |
859 | ||
860 | /* | |
861 | * allocate context descriptor | |
862 | * must be able to free with interrupts disabled | |
863 | */ | |
52fd9108 | 864 | ctx = kzalloc(sizeof(pfm_context_t), GFP_KERNEL); |
1da177e4 | 865 | if (ctx) { |
1da177e4 | 866 | DPRINT(("alloc ctx @%p\n", ctx)); |
f8e811b9 AV |
867 | |
868 | /* | |
869 | * init context protection lock | |
870 | */ | |
871 | spin_lock_init(&ctx->ctx_lock); | |
872 | ||
873 | /* | |
874 | * context is unloaded | |
875 | */ | |
876 | ctx->ctx_state = PFM_CTX_UNLOADED; | |
877 | ||
878 | /* | |
879 | * initialization of context's flags | |
880 | */ | |
881 | ctx->ctx_fl_block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0; | |
882 | ctx->ctx_fl_system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0; | |
883 | ctx->ctx_fl_no_msg = (ctx_flags & PFM_FL_OVFL_NO_MSG) ? 1: 0; | |
884 | /* | |
885 | * will move to set properties | |
886 | * ctx->ctx_fl_excl_idle = (ctx_flags & PFM_FL_EXCL_IDLE) ? 1: 0; | |
887 | */ | |
888 | ||
889 | /* | |
890 | * init restart semaphore to locked | |
891 | */ | |
892 | init_completion(&ctx->ctx_restart_done); | |
893 | ||
894 | /* | |
895 | * activation is used in SMP only | |
896 | */ | |
897 | ctx->ctx_last_activation = PFM_INVALID_ACTIVATION; | |
898 | SET_LAST_CPU(ctx, -1); | |
899 | ||
900 | /* | |
901 | * initialize notification message queue | |
902 | */ | |
903 | ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0; | |
904 | init_waitqueue_head(&ctx->ctx_msgq_wait); | |
905 | init_waitqueue_head(&ctx->ctx_zombieq); | |
906 | ||
1da177e4 LT |
907 | } |
908 | return ctx; | |
909 | } | |
910 | ||
911 | static void | |
912 | pfm_context_free(pfm_context_t *ctx) | |
913 | { | |
914 | if (ctx) { | |
915 | DPRINT(("free ctx @%p\n", ctx)); | |
916 | kfree(ctx); | |
917 | } | |
918 | } | |
919 | ||
920 | static void | |
921 | pfm_mask_monitoring(struct task_struct *task) | |
922 | { | |
923 | pfm_context_t *ctx = PFM_GET_CTX(task); | |
1da177e4 LT |
924 | unsigned long mask, val, ovfl_mask; |
925 | int i; | |
926 | ||
19c5870c | 927 | DPRINT_ovfl(("masking monitoring for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
928 | |
929 | ovfl_mask = pmu_conf->ovfl_val; | |
930 | /* | |
931 | * monitoring can only be masked as a result of a valid | |
932 | * counter overflow. In UP, it means that the PMU still | |
933 | * has an owner. Note that the owner can be different | |
934 | * from the current task. However the PMU state belongs | |
935 | * to the owner. | |
936 | * In SMP, a valid overflow only happens when task is | |
937 | * current. Therefore if we come here, we know that | |
938 | * the PMU state belongs to the current task, therefore | |
939 | * we can access the live registers. | |
940 | * | |
941 | * So in both cases, the live register contains the owner's | |
942 | * state. We can ONLY touch the PMU registers and NOT the PSR. | |
943 | * | |
35589a8f | 944 | * As a consequence to this call, the ctx->th_pmds[] array |
1da177e4 LT |
945 | * contains stale information which must be ignored |
946 | * when context is reloaded AND monitoring is active (see | |
947 | * pfm_restart). | |
948 | */ | |
949 | mask = ctx->ctx_used_pmds[0]; | |
950 | for (i = 0; mask; i++, mask>>=1) { | |
951 | /* skip non used pmds */ | |
952 | if ((mask & 0x1) == 0) continue; | |
953 | val = ia64_get_pmd(i); | |
954 | ||
955 | if (PMD_IS_COUNTING(i)) { | |
956 | /* | |
957 | * we rebuild the full 64 bit value of the counter | |
958 | */ | |
959 | ctx->ctx_pmds[i].val += (val & ovfl_mask); | |
960 | } else { | |
961 | ctx->ctx_pmds[i].val = val; | |
962 | } | |
963 | DPRINT_ovfl(("pmd[%d]=0x%lx hw_pmd=0x%lx\n", | |
964 | i, | |
965 | ctx->ctx_pmds[i].val, | |
966 | val & ovfl_mask)); | |
967 | } | |
968 | /* | |
969 | * mask monitoring by setting the privilege level to 0 | |
970 | * we cannot use psr.pp/psr.up for this, it is controlled by | |
971 | * the user | |
972 | * | |
973 | * if task is current, modify actual registers, otherwise modify | |
974 | * thread save state, i.e., what will be restored in pfm_load_regs() | |
975 | */ | |
976 | mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER; | |
977 | for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) { | |
978 | if ((mask & 0x1) == 0UL) continue; | |
35589a8f KA |
979 | ia64_set_pmc(i, ctx->th_pmcs[i] & ~0xfUL); |
980 | ctx->th_pmcs[i] &= ~0xfUL; | |
981 | DPRINT_ovfl(("pmc[%d]=0x%lx\n", i, ctx->th_pmcs[i])); | |
1da177e4 LT |
982 | } |
983 | /* | |
984 | * make all of this visible | |
985 | */ | |
986 | ia64_srlz_d(); | |
987 | } | |
988 | ||
989 | /* | |
990 | * must always be done with task == current | |
991 | * | |
992 | * context must be in MASKED state when calling | |
993 | */ | |
994 | static void | |
995 | pfm_restore_monitoring(struct task_struct *task) | |
996 | { | |
997 | pfm_context_t *ctx = PFM_GET_CTX(task); | |
1da177e4 LT |
998 | unsigned long mask, ovfl_mask; |
999 | unsigned long psr, val; | |
1000 | int i, is_system; | |
1001 | ||
1002 | is_system = ctx->ctx_fl_system; | |
1003 | ovfl_mask = pmu_conf->ovfl_val; | |
1004 | ||
1005 | if (task != current) { | |
19c5870c | 1006 | printk(KERN_ERR "perfmon.%d: invalid task[%d] current[%d]\n", __LINE__, task_pid_nr(task), task_pid_nr(current)); |
1da177e4 LT |
1007 | return; |
1008 | } | |
1009 | if (ctx->ctx_state != PFM_CTX_MASKED) { | |
1010 | printk(KERN_ERR "perfmon.%d: task[%d] current[%d] invalid state=%d\n", __LINE__, | |
19c5870c | 1011 | task_pid_nr(task), task_pid_nr(current), ctx->ctx_state); |
1da177e4 LT |
1012 | return; |
1013 | } | |
1014 | psr = pfm_get_psr(); | |
1015 | /* | |
1016 | * monitoring is masked via the PMC. | |
1017 | * As we restore their value, we do not want each counter to | |
1018 | * restart right away. We stop monitoring using the PSR, | |
1019 | * restore the PMC (and PMD) and then re-establish the psr | |
1020 | * as it was. Note that there can be no pending overflow at | |
1021 | * this point, because monitoring was MASKED. | |
1022 | * | |
1023 | * system-wide session are pinned and self-monitoring | |
1024 | */ | |
1025 | if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) { | |
1026 | /* disable dcr pp */ | |
1027 | ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP); | |
1028 | pfm_clear_psr_pp(); | |
1029 | } else { | |
1030 | pfm_clear_psr_up(); | |
1031 | } | |
1032 | /* | |
1033 | * first, we restore the PMD | |
1034 | */ | |
1035 | mask = ctx->ctx_used_pmds[0]; | |
1036 | for (i = 0; mask; i++, mask>>=1) { | |
1037 | /* skip non used pmds */ | |
1038 | if ((mask & 0x1) == 0) continue; | |
1039 | ||
1040 | if (PMD_IS_COUNTING(i)) { | |
1041 | /* | |
1042 | * we split the 64bit value according to | |
1043 | * counter width | |
1044 | */ | |
1045 | val = ctx->ctx_pmds[i].val & ovfl_mask; | |
1046 | ctx->ctx_pmds[i].val &= ~ovfl_mask; | |
1047 | } else { | |
1048 | val = ctx->ctx_pmds[i].val; | |
1049 | } | |
1050 | ia64_set_pmd(i, val); | |
1051 | ||
1052 | DPRINT(("pmd[%d]=0x%lx hw_pmd=0x%lx\n", | |
1053 | i, | |
1054 | ctx->ctx_pmds[i].val, | |
1055 | val)); | |
1056 | } | |
1057 | /* | |
1058 | * restore the PMCs | |
1059 | */ | |
1060 | mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER; | |
1061 | for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) { | |
1062 | if ((mask & 0x1) == 0UL) continue; | |
35589a8f KA |
1063 | ctx->th_pmcs[i] = ctx->ctx_pmcs[i]; |
1064 | ia64_set_pmc(i, ctx->th_pmcs[i]); | |
19c5870c AD |
1065 | DPRINT(("[%d] pmc[%d]=0x%lx\n", |
1066 | task_pid_nr(task), i, ctx->th_pmcs[i])); | |
1da177e4 LT |
1067 | } |
1068 | ia64_srlz_d(); | |
1069 | ||
1070 | /* | |
1071 | * must restore DBR/IBR because could be modified while masked | |
1072 | * XXX: need to optimize | |
1073 | */ | |
1074 | if (ctx->ctx_fl_using_dbreg) { | |
1075 | pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); | |
1076 | pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); | |
1077 | } | |
1078 | ||
1079 | /* | |
1080 | * now restore PSR | |
1081 | */ | |
1082 | if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) { | |
1083 | /* enable dcr pp */ | |
1084 | ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP); | |
1085 | ia64_srlz_i(); | |
1086 | } | |
1087 | pfm_set_psr_l(psr); | |
1088 | } | |
1089 | ||
1090 | static inline void | |
1091 | pfm_save_pmds(unsigned long *pmds, unsigned long mask) | |
1092 | { | |
1093 | int i; | |
1094 | ||
1095 | ia64_srlz_d(); | |
1096 | ||
1097 | for (i=0; mask; i++, mask>>=1) { | |
1098 | if (mask & 0x1) pmds[i] = ia64_get_pmd(i); | |
1099 | } | |
1100 | } | |
1101 | ||
1102 | /* | |
1103 | * reload from thread state (used for ctxw only) | |
1104 | */ | |
1105 | static inline void | |
1106 | pfm_restore_pmds(unsigned long *pmds, unsigned long mask) | |
1107 | { | |
1108 | int i; | |
1109 | unsigned long val, ovfl_val = pmu_conf->ovfl_val; | |
1110 | ||
1111 | for (i=0; mask; i++, mask>>=1) { | |
1112 | if ((mask & 0x1) == 0) continue; | |
1113 | val = PMD_IS_COUNTING(i) ? pmds[i] & ovfl_val : pmds[i]; | |
1114 | ia64_set_pmd(i, val); | |
1115 | } | |
1116 | ia64_srlz_d(); | |
1117 | } | |
1118 | ||
1119 | /* | |
1120 | * propagate PMD from context to thread-state | |
1121 | */ | |
1122 | static inline void | |
1123 | pfm_copy_pmds(struct task_struct *task, pfm_context_t *ctx) | |
1124 | { | |
1da177e4 LT |
1125 | unsigned long ovfl_val = pmu_conf->ovfl_val; |
1126 | unsigned long mask = ctx->ctx_all_pmds[0]; | |
1127 | unsigned long val; | |
1128 | int i; | |
1129 | ||
1130 | DPRINT(("mask=0x%lx\n", mask)); | |
1131 | ||
1132 | for (i=0; mask; i++, mask>>=1) { | |
1133 | ||
1134 | val = ctx->ctx_pmds[i].val; | |
1135 | ||
1136 | /* | |
1137 | * We break up the 64 bit value into 2 pieces | |
1138 | * the lower bits go to the machine state in the | |
1139 | * thread (will be reloaded on ctxsw in). | |
1140 | * The upper part stays in the soft-counter. | |
1141 | */ | |
1142 | if (PMD_IS_COUNTING(i)) { | |
1143 | ctx->ctx_pmds[i].val = val & ~ovfl_val; | |
1144 | val &= ovfl_val; | |
1145 | } | |
35589a8f | 1146 | ctx->th_pmds[i] = val; |
1da177e4 LT |
1147 | |
1148 | DPRINT(("pmd[%d]=0x%lx soft_val=0x%lx\n", | |
1149 | i, | |
35589a8f | 1150 | ctx->th_pmds[i], |
1da177e4 LT |
1151 | ctx->ctx_pmds[i].val)); |
1152 | } | |
1153 | } | |
1154 | ||
1155 | /* | |
1156 | * propagate PMC from context to thread-state | |
1157 | */ | |
1158 | static inline void | |
1159 | pfm_copy_pmcs(struct task_struct *task, pfm_context_t *ctx) | |
1160 | { | |
1da177e4 LT |
1161 | unsigned long mask = ctx->ctx_all_pmcs[0]; |
1162 | int i; | |
1163 | ||
1164 | DPRINT(("mask=0x%lx\n", mask)); | |
1165 | ||
1166 | for (i=0; mask; i++, mask>>=1) { | |
1167 | /* masking 0 with ovfl_val yields 0 */ | |
35589a8f KA |
1168 | ctx->th_pmcs[i] = ctx->ctx_pmcs[i]; |
1169 | DPRINT(("pmc[%d]=0x%lx\n", i, ctx->th_pmcs[i])); | |
1da177e4 LT |
1170 | } |
1171 | } | |
1172 | ||
1173 | ||
1174 | ||
1175 | static inline void | |
1176 | pfm_restore_pmcs(unsigned long *pmcs, unsigned long mask) | |
1177 | { | |
1178 | int i; | |
1179 | ||
1180 | for (i=0; mask; i++, mask>>=1) { | |
1181 | if ((mask & 0x1) == 0) continue; | |
1182 | ia64_set_pmc(i, pmcs[i]); | |
1183 | } | |
1184 | ia64_srlz_d(); | |
1185 | } | |
1186 | ||
1187 | static inline int | |
1188 | pfm_uuid_cmp(pfm_uuid_t a, pfm_uuid_t b) | |
1189 | { | |
1190 | return memcmp(a, b, sizeof(pfm_uuid_t)); | |
1191 | } | |
1192 | ||
1193 | static inline int | |
1194 | pfm_buf_fmt_exit(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, struct pt_regs *regs) | |
1195 | { | |
1196 | int ret = 0; | |
1197 | if (fmt->fmt_exit) ret = (*fmt->fmt_exit)(task, buf, regs); | |
1198 | return ret; | |
1199 | } | |
1200 | ||
1201 | static inline int | |
1202 | pfm_buf_fmt_getsize(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, int cpu, void *arg, unsigned long *size) | |
1203 | { | |
1204 | int ret = 0; | |
1205 | if (fmt->fmt_getsize) ret = (*fmt->fmt_getsize)(task, flags, cpu, arg, size); | |
1206 | return ret; | |
1207 | } | |
1208 | ||
1209 | ||
1210 | static inline int | |
1211 | pfm_buf_fmt_validate(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, | |
1212 | int cpu, void *arg) | |
1213 | { | |
1214 | int ret = 0; | |
1215 | if (fmt->fmt_validate) ret = (*fmt->fmt_validate)(task, flags, cpu, arg); | |
1216 | return ret; | |
1217 | } | |
1218 | ||
1219 | static inline int | |
1220 | pfm_buf_fmt_init(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, unsigned int flags, | |
1221 | int cpu, void *arg) | |
1222 | { | |
1223 | int ret = 0; | |
1224 | if (fmt->fmt_init) ret = (*fmt->fmt_init)(task, buf, flags, cpu, arg); | |
1225 | return ret; | |
1226 | } | |
1227 | ||
1228 | static inline int | |
1229 | pfm_buf_fmt_restart(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs) | |
1230 | { | |
1231 | int ret = 0; | |
1232 | if (fmt->fmt_restart) ret = (*fmt->fmt_restart)(task, ctrl, buf, regs); | |
1233 | return ret; | |
1234 | } | |
1235 | ||
1236 | static inline int | |
1237 | pfm_buf_fmt_restart_active(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs) | |
1238 | { | |
1239 | int ret = 0; | |
1240 | if (fmt->fmt_restart_active) ret = (*fmt->fmt_restart_active)(task, ctrl, buf, regs); | |
1241 | return ret; | |
1242 | } | |
1243 | ||
1244 | static pfm_buffer_fmt_t * | |
1245 | __pfm_find_buffer_fmt(pfm_uuid_t uuid) | |
1246 | { | |
1247 | struct list_head * pos; | |
1248 | pfm_buffer_fmt_t * entry; | |
1249 | ||
1250 | list_for_each(pos, &pfm_buffer_fmt_list) { | |
1251 | entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list); | |
1252 | if (pfm_uuid_cmp(uuid, entry->fmt_uuid) == 0) | |
1253 | return entry; | |
1254 | } | |
1255 | return NULL; | |
1256 | } | |
1257 | ||
1258 | /* | |
1259 | * find a buffer format based on its uuid | |
1260 | */ | |
1261 | static pfm_buffer_fmt_t * | |
1262 | pfm_find_buffer_fmt(pfm_uuid_t uuid) | |
1263 | { | |
1264 | pfm_buffer_fmt_t * fmt; | |
1265 | spin_lock(&pfm_buffer_fmt_lock); | |
1266 | fmt = __pfm_find_buffer_fmt(uuid); | |
1267 | spin_unlock(&pfm_buffer_fmt_lock); | |
1268 | return fmt; | |
1269 | } | |
1270 | ||
1271 | int | |
1272 | pfm_register_buffer_fmt(pfm_buffer_fmt_t *fmt) | |
1273 | { | |
1274 | int ret = 0; | |
1275 | ||
1276 | /* some sanity checks */ | |
1277 | if (fmt == NULL || fmt->fmt_name == NULL) return -EINVAL; | |
1278 | ||
1279 | /* we need at least a handler */ | |
1280 | if (fmt->fmt_handler == NULL) return -EINVAL; | |
1281 | ||
1282 | /* | |
1283 | * XXX: need check validity of fmt_arg_size | |
1284 | */ | |
1285 | ||
1286 | spin_lock(&pfm_buffer_fmt_lock); | |
1287 | ||
1288 | if (__pfm_find_buffer_fmt(fmt->fmt_uuid)) { | |
1289 | printk(KERN_ERR "perfmon: duplicate sampling format: %s\n", fmt->fmt_name); | |
1290 | ret = -EBUSY; | |
1291 | goto out; | |
1292 | } | |
1293 | list_add(&fmt->fmt_list, &pfm_buffer_fmt_list); | |
1294 | printk(KERN_INFO "perfmon: added sampling format %s\n", fmt->fmt_name); | |
1295 | ||
1296 | out: | |
1297 | spin_unlock(&pfm_buffer_fmt_lock); | |
1298 | return ret; | |
1299 | } | |
1300 | EXPORT_SYMBOL(pfm_register_buffer_fmt); | |
1301 | ||
1302 | int | |
1303 | pfm_unregister_buffer_fmt(pfm_uuid_t uuid) | |
1304 | { | |
1305 | pfm_buffer_fmt_t *fmt; | |
1306 | int ret = 0; | |
1307 | ||
1308 | spin_lock(&pfm_buffer_fmt_lock); | |
1309 | ||
1310 | fmt = __pfm_find_buffer_fmt(uuid); | |
1311 | if (!fmt) { | |
1312 | printk(KERN_ERR "perfmon: cannot unregister format, not found\n"); | |
1313 | ret = -EINVAL; | |
1314 | goto out; | |
1315 | } | |
1316 | list_del_init(&fmt->fmt_list); | |
1317 | printk(KERN_INFO "perfmon: removed sampling format: %s\n", fmt->fmt_name); | |
1318 | ||
1319 | out: | |
1320 | spin_unlock(&pfm_buffer_fmt_lock); | |
1321 | return ret; | |
1322 | ||
1323 | } | |
1324 | EXPORT_SYMBOL(pfm_unregister_buffer_fmt); | |
1325 | ||
1326 | static int | |
1327 | pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu) | |
1328 | { | |
1329 | unsigned long flags; | |
1330 | /* | |
72fdbdce | 1331 | * validity checks on cpu_mask have been done upstream |
1da177e4 LT |
1332 | */ |
1333 | LOCK_PFS(flags); | |
1334 | ||
1335 | DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", | |
1336 | pfm_sessions.pfs_sys_sessions, | |
1337 | pfm_sessions.pfs_task_sessions, | |
1338 | pfm_sessions.pfs_sys_use_dbregs, | |
1339 | is_syswide, | |
1340 | cpu)); | |
1341 | ||
1342 | if (is_syswide) { | |
1343 | /* | |
1344 | * cannot mix system wide and per-task sessions | |
1345 | */ | |
1346 | if (pfm_sessions.pfs_task_sessions > 0UL) { | |
1347 | DPRINT(("system wide not possible, %u conflicting task_sessions\n", | |
1348 | pfm_sessions.pfs_task_sessions)); | |
1349 | goto abort; | |
1350 | } | |
1351 | ||
1352 | if (pfm_sessions.pfs_sys_session[cpu]) goto error_conflict; | |
1353 | ||
1354 | DPRINT(("reserving system wide session on CPU%u currently on CPU%u\n", cpu, smp_processor_id())); | |
1355 | ||
1356 | pfm_sessions.pfs_sys_session[cpu] = task; | |
1357 | ||
1358 | pfm_sessions.pfs_sys_sessions++ ; | |
1359 | ||
1360 | } else { | |
1361 | if (pfm_sessions.pfs_sys_sessions) goto abort; | |
1362 | pfm_sessions.pfs_task_sessions++; | |
1363 | } | |
1364 | ||
1365 | DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", | |
1366 | pfm_sessions.pfs_sys_sessions, | |
1367 | pfm_sessions.pfs_task_sessions, | |
1368 | pfm_sessions.pfs_sys_use_dbregs, | |
1369 | is_syswide, | |
1370 | cpu)); | |
1371 | ||
8df5a500 | 1372 | /* |
91d591c3 | 1373 | * Force idle() into poll mode |
8df5a500 | 1374 | */ |
91d591c3 | 1375 | cpu_idle_poll_ctrl(true); |
8df5a500 | 1376 | |
1da177e4 LT |
1377 | UNLOCK_PFS(flags); |
1378 | ||
1379 | return 0; | |
1380 | ||
1381 | error_conflict: | |
1382 | DPRINT(("system wide not possible, conflicting session [%d] on CPU%d\n", | |
19c5870c | 1383 | task_pid_nr(pfm_sessions.pfs_sys_session[cpu]), |
a1ecf7f6 | 1384 | cpu)); |
1da177e4 LT |
1385 | abort: |
1386 | UNLOCK_PFS(flags); | |
1387 | ||
1388 | return -EBUSY; | |
1389 | ||
1390 | } | |
1391 | ||
1392 | static int | |
1393 | pfm_unreserve_session(pfm_context_t *ctx, int is_syswide, unsigned int cpu) | |
1394 | { | |
1395 | unsigned long flags; | |
1396 | /* | |
72fdbdce | 1397 | * validity checks on cpu_mask have been done upstream |
1da177e4 LT |
1398 | */ |
1399 | LOCK_PFS(flags); | |
1400 | ||
1401 | DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", | |
1402 | pfm_sessions.pfs_sys_sessions, | |
1403 | pfm_sessions.pfs_task_sessions, | |
1404 | pfm_sessions.pfs_sys_use_dbregs, | |
1405 | is_syswide, | |
1406 | cpu)); | |
1407 | ||
1408 | ||
1409 | if (is_syswide) { | |
1410 | pfm_sessions.pfs_sys_session[cpu] = NULL; | |
1411 | /* | |
1412 | * would not work with perfmon+more than one bit in cpu_mask | |
1413 | */ | |
1414 | if (ctx && ctx->ctx_fl_using_dbreg) { | |
1415 | if (pfm_sessions.pfs_sys_use_dbregs == 0) { | |
1416 | printk(KERN_ERR "perfmon: invalid release for ctx %p sys_use_dbregs=0\n", ctx); | |
1417 | } else { | |
1418 | pfm_sessions.pfs_sys_use_dbregs--; | |
1419 | } | |
1420 | } | |
1421 | pfm_sessions.pfs_sys_sessions--; | |
1422 | } else { | |
1423 | pfm_sessions.pfs_task_sessions--; | |
1424 | } | |
1425 | DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", | |
1426 | pfm_sessions.pfs_sys_sessions, | |
1427 | pfm_sessions.pfs_task_sessions, | |
1428 | pfm_sessions.pfs_sys_use_dbregs, | |
1429 | is_syswide, | |
1430 | cpu)); | |
1431 | ||
91d591c3 TG |
1432 | /* Undo forced polling. Last session reenables pal_halt */ |
1433 | cpu_idle_poll_ctrl(false); | |
8df5a500 | 1434 | |
1da177e4 LT |
1435 | UNLOCK_PFS(flags); |
1436 | ||
1437 | return 0; | |
1438 | } | |
1439 | ||
1440 | /* | |
1441 | * removes virtual mapping of the sampling buffer. | |
1442 | * IMPORTANT: cannot be called with interrupts disable, e.g. inside | |
1443 | * a PROTECT_CTX() section. | |
1444 | */ | |
1445 | static int | |
9f3a4afb | 1446 | pfm_remove_smpl_mapping(void *vaddr, unsigned long size) |
1da177e4 | 1447 | { |
9f3a4afb | 1448 | struct task_struct *task = current; |
1da177e4 LT |
1449 | int r; |
1450 | ||
1451 | /* sanity checks */ | |
1452 | if (task->mm == NULL || size == 0UL || vaddr == NULL) { | |
19c5870c | 1453 | printk(KERN_ERR "perfmon: pfm_remove_smpl_mapping [%d] invalid context mm=%p\n", task_pid_nr(task), task->mm); |
1da177e4 LT |
1454 | return -EINVAL; |
1455 | } | |
1456 | ||
1457 | DPRINT(("smpl_vaddr=%p size=%lu\n", vaddr, size)); | |
1458 | ||
1459 | /* | |
1460 | * does the actual unmapping | |
1461 | */ | |
bfce281c | 1462 | r = vm_munmap((unsigned long)vaddr, size); |
1da177e4 | 1463 | |
1da177e4 | 1464 | if (r !=0) { |
19c5870c | 1465 | printk(KERN_ERR "perfmon: [%d] unable to unmap sampling buffer @%p size=%lu\n", task_pid_nr(task), vaddr, size); |
1da177e4 LT |
1466 | } |
1467 | ||
1468 | DPRINT(("do_unmap(%p, %lu)=%d\n", vaddr, size, r)); | |
1469 | ||
1470 | return 0; | |
1471 | } | |
1472 | ||
1473 | /* | |
1474 | * free actual physical storage used by sampling buffer | |
1475 | */ | |
1476 | #if 0 | |
1477 | static int | |
1478 | pfm_free_smpl_buffer(pfm_context_t *ctx) | |
1479 | { | |
1480 | pfm_buffer_fmt_t *fmt; | |
1481 | ||
1482 | if (ctx->ctx_smpl_hdr == NULL) goto invalid_free; | |
1483 | ||
1484 | /* | |
1485 | * we won't use the buffer format anymore | |
1486 | */ | |
1487 | fmt = ctx->ctx_buf_fmt; | |
1488 | ||
1489 | DPRINT(("sampling buffer @%p size %lu vaddr=%p\n", | |
1490 | ctx->ctx_smpl_hdr, | |
1491 | ctx->ctx_smpl_size, | |
1492 | ctx->ctx_smpl_vaddr)); | |
1493 | ||
1494 | pfm_buf_fmt_exit(fmt, current, NULL, NULL); | |
1495 | ||
1496 | /* | |
1497 | * free the buffer | |
1498 | */ | |
1499 | pfm_rvfree(ctx->ctx_smpl_hdr, ctx->ctx_smpl_size); | |
1500 | ||
1501 | ctx->ctx_smpl_hdr = NULL; | |
1502 | ctx->ctx_smpl_size = 0UL; | |
1503 | ||
1504 | return 0; | |
1505 | ||
1506 | invalid_free: | |
19c5870c | 1507 | printk(KERN_ERR "perfmon: pfm_free_smpl_buffer [%d] no buffer\n", task_pid_nr(current)); |
1da177e4 LT |
1508 | return -EINVAL; |
1509 | } | |
1510 | #endif | |
1511 | ||
1512 | static inline void | |
1513 | pfm_exit_smpl_buffer(pfm_buffer_fmt_t *fmt) | |
1514 | { | |
1515 | if (fmt == NULL) return; | |
1516 | ||
1517 | pfm_buf_fmt_exit(fmt, current, NULL, NULL); | |
1518 | ||
1519 | } | |
1520 | ||
1521 | /* | |
1522 | * pfmfs should _never_ be mounted by userland - too much of security hassle, | |
1523 | * no real gain from having the whole whorehouse mounted. So we don't need | |
1524 | * any operations on the root directory. However, we need a non-trivial | |
1525 | * d_name - pfm: will go nicely and kill the special-casing in procfs. | |
1526 | */ | |
b3e19d92 | 1527 | static struct vfsmount *pfmfs_mnt __read_mostly; |
1da177e4 LT |
1528 | |
1529 | static int __init | |
1530 | init_pfm_fs(void) | |
1531 | { | |
1532 | int err = register_filesystem(&pfm_fs_type); | |
1533 | if (!err) { | |
1534 | pfmfs_mnt = kern_mount(&pfm_fs_type); | |
1535 | err = PTR_ERR(pfmfs_mnt); | |
1536 | if (IS_ERR(pfmfs_mnt)) | |
1537 | unregister_filesystem(&pfm_fs_type); | |
1538 | else | |
1539 | err = 0; | |
1540 | } | |
1541 | return err; | |
1542 | } | |
1543 | ||
1da177e4 LT |
1544 | static ssize_t |
1545 | pfm_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos) | |
1546 | { | |
1547 | pfm_context_t *ctx; | |
1548 | pfm_msg_t *msg; | |
1549 | ssize_t ret; | |
1550 | unsigned long flags; | |
1551 | DECLARE_WAITQUEUE(wait, current); | |
1552 | if (PFM_IS_FILE(filp) == 0) { | |
19c5870c | 1553 | printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1554 | return -EINVAL; |
1555 | } | |
1556 | ||
df0a59a1 | 1557 | ctx = filp->private_data; |
1da177e4 | 1558 | if (ctx == NULL) { |
19c5870c | 1559 | printk(KERN_ERR "perfmon: pfm_read: NULL ctx [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1560 | return -EINVAL; |
1561 | } | |
1562 | ||
1563 | /* | |
1564 | * check even when there is no message | |
1565 | */ | |
1566 | if (size < sizeof(pfm_msg_t)) { | |
1567 | DPRINT(("message is too small ctx=%p (>=%ld)\n", ctx, sizeof(pfm_msg_t))); | |
1568 | return -EINVAL; | |
1569 | } | |
1570 | ||
1571 | PROTECT_CTX(ctx, flags); | |
1572 | ||
1573 | /* | |
1574 | * put ourselves on the wait queue | |
1575 | */ | |
1576 | add_wait_queue(&ctx->ctx_msgq_wait, &wait); | |
1577 | ||
1578 | ||
1579 | for(;;) { | |
1580 | /* | |
1581 | * check wait queue | |
1582 | */ | |
1583 | ||
1584 | set_current_state(TASK_INTERRUPTIBLE); | |
1585 | ||
1586 | DPRINT(("head=%d tail=%d\n", ctx->ctx_msgq_head, ctx->ctx_msgq_tail)); | |
1587 | ||
1588 | ret = 0; | |
1589 | if(PFM_CTXQ_EMPTY(ctx) == 0) break; | |
1590 | ||
1591 | UNPROTECT_CTX(ctx, flags); | |
1592 | ||
1593 | /* | |
1594 | * check non-blocking read | |
1595 | */ | |
1596 | ret = -EAGAIN; | |
1597 | if(filp->f_flags & O_NONBLOCK) break; | |
1598 | ||
1599 | /* | |
1600 | * check pending signals | |
1601 | */ | |
1602 | if(signal_pending(current)) { | |
1603 | ret = -EINTR; | |
1604 | break; | |
1605 | } | |
1606 | /* | |
1607 | * no message, so wait | |
1608 | */ | |
1609 | schedule(); | |
1610 | ||
1611 | PROTECT_CTX(ctx, flags); | |
1612 | } | |
19c5870c | 1613 | DPRINT(("[%d] back to running ret=%ld\n", task_pid_nr(current), ret)); |
1da177e4 LT |
1614 | set_current_state(TASK_RUNNING); |
1615 | remove_wait_queue(&ctx->ctx_msgq_wait, &wait); | |
1616 | ||
1617 | if (ret < 0) goto abort; | |
1618 | ||
1619 | ret = -EINVAL; | |
1620 | msg = pfm_get_next_msg(ctx); | |
1621 | if (msg == NULL) { | |
19c5870c | 1622 | printk(KERN_ERR "perfmon: pfm_read no msg for ctx=%p [%d]\n", ctx, task_pid_nr(current)); |
1da177e4 LT |
1623 | goto abort_locked; |
1624 | } | |
1625 | ||
4944930a | 1626 | DPRINT(("fd=%d type=%d\n", msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type)); |
1da177e4 LT |
1627 | |
1628 | ret = -EFAULT; | |
1629 | if(copy_to_user(buf, msg, sizeof(pfm_msg_t)) == 0) ret = sizeof(pfm_msg_t); | |
1630 | ||
1631 | abort_locked: | |
1632 | UNPROTECT_CTX(ctx, flags); | |
1633 | abort: | |
1634 | return ret; | |
1635 | } | |
1636 | ||
1637 | static ssize_t | |
1638 | pfm_write(struct file *file, const char __user *ubuf, | |
1639 | size_t size, loff_t *ppos) | |
1640 | { | |
1641 | DPRINT(("pfm_write called\n")); | |
1642 | return -EINVAL; | |
1643 | } | |
1644 | ||
1645 | static unsigned int | |
1646 | pfm_poll(struct file *filp, poll_table * wait) | |
1647 | { | |
1648 | pfm_context_t *ctx; | |
1649 | unsigned long flags; | |
1650 | unsigned int mask = 0; | |
1651 | ||
1652 | if (PFM_IS_FILE(filp) == 0) { | |
19c5870c | 1653 | printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1654 | return 0; |
1655 | } | |
1656 | ||
df0a59a1 | 1657 | ctx = filp->private_data; |
1da177e4 | 1658 | if (ctx == NULL) { |
19c5870c | 1659 | printk(KERN_ERR "perfmon: pfm_poll: NULL ctx [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1660 | return 0; |
1661 | } | |
1662 | ||
1663 | ||
1664 | DPRINT(("pfm_poll ctx_fd=%d before poll_wait\n", ctx->ctx_fd)); | |
1665 | ||
1666 | poll_wait(filp, &ctx->ctx_msgq_wait, wait); | |
1667 | ||
1668 | PROTECT_CTX(ctx, flags); | |
1669 | ||
1670 | if (PFM_CTXQ_EMPTY(ctx) == 0) | |
1671 | mask = POLLIN | POLLRDNORM; | |
1672 | ||
1673 | UNPROTECT_CTX(ctx, flags); | |
1674 | ||
1675 | DPRINT(("pfm_poll ctx_fd=%d mask=0x%x\n", ctx->ctx_fd, mask)); | |
1676 | ||
1677 | return mask; | |
1678 | } | |
1679 | ||
ba58aebf AB |
1680 | static long |
1681 | pfm_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
1da177e4 LT |
1682 | { |
1683 | DPRINT(("pfm_ioctl called\n")); | |
1684 | return -EINVAL; | |
1685 | } | |
1686 | ||
1687 | /* | |
1688 | * interrupt cannot be masked when coming here | |
1689 | */ | |
1690 | static inline int | |
1691 | pfm_do_fasync(int fd, struct file *filp, pfm_context_t *ctx, int on) | |
1692 | { | |
1693 | int ret; | |
1694 | ||
1695 | ret = fasync_helper (fd, filp, on, &ctx->ctx_async_queue); | |
1696 | ||
1697 | DPRINT(("pfm_fasync called by [%d] on ctx_fd=%d on=%d async_queue=%p ret=%d\n", | |
19c5870c | 1698 | task_pid_nr(current), |
1da177e4 LT |
1699 | fd, |
1700 | on, | |
1701 | ctx->ctx_async_queue, ret)); | |
1702 | ||
1703 | return ret; | |
1704 | } | |
1705 | ||
1706 | static int | |
1707 | pfm_fasync(int fd, struct file *filp, int on) | |
1708 | { | |
1709 | pfm_context_t *ctx; | |
1710 | int ret; | |
1711 | ||
1712 | if (PFM_IS_FILE(filp) == 0) { | |
19c5870c | 1713 | printk(KERN_ERR "perfmon: pfm_fasync bad magic [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1714 | return -EBADF; |
1715 | } | |
1716 | ||
df0a59a1 | 1717 | ctx = filp->private_data; |
1da177e4 | 1718 | if (ctx == NULL) { |
19c5870c | 1719 | printk(KERN_ERR "perfmon: pfm_fasync NULL ctx [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1720 | return -EBADF; |
1721 | } | |
1722 | /* | |
1723 | * we cannot mask interrupts during this call because this may | |
1724 | * may go to sleep if memory is not readily avalaible. | |
1725 | * | |
1726 | * We are protected from the conetxt disappearing by the get_fd()/put_fd() | |
1727 | * done in caller. Serialization of this function is ensured by caller. | |
1728 | */ | |
1729 | ret = pfm_do_fasync(fd, filp, ctx, on); | |
1730 | ||
1731 | ||
1732 | DPRINT(("pfm_fasync called on ctx_fd=%d on=%d async_queue=%p ret=%d\n", | |
1733 | fd, | |
1734 | on, | |
1735 | ctx->ctx_async_queue, ret)); | |
1736 | ||
1737 | return ret; | |
1738 | } | |
1739 | ||
1740 | #ifdef CONFIG_SMP | |
1741 | /* | |
1742 | * this function is exclusively called from pfm_close(). | |
1743 | * The context is not protected at that time, nor are interrupts | |
1744 | * on the remote CPU. That's necessary to avoid deadlocks. | |
1745 | */ | |
1746 | static void | |
1747 | pfm_syswide_force_stop(void *info) | |
1748 | { | |
1749 | pfm_context_t *ctx = (pfm_context_t *)info; | |
6450578f | 1750 | struct pt_regs *regs = task_pt_regs(current); |
1da177e4 LT |
1751 | struct task_struct *owner; |
1752 | unsigned long flags; | |
1753 | int ret; | |
1754 | ||
1755 | if (ctx->ctx_cpu != smp_processor_id()) { | |
1756 | printk(KERN_ERR "perfmon: pfm_syswide_force_stop for CPU%d but on CPU%d\n", | |
1757 | ctx->ctx_cpu, | |
1758 | smp_processor_id()); | |
1759 | return; | |
1760 | } | |
1761 | owner = GET_PMU_OWNER(); | |
1762 | if (owner != ctx->ctx_task) { | |
1763 | printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected owner [%d] instead of [%d]\n", | |
1764 | smp_processor_id(), | |
19c5870c | 1765 | task_pid_nr(owner), task_pid_nr(ctx->ctx_task)); |
1da177e4 LT |
1766 | return; |
1767 | } | |
1768 | if (GET_PMU_CTX() != ctx) { | |
1769 | printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected ctx %p instead of %p\n", | |
1770 | smp_processor_id(), | |
1771 | GET_PMU_CTX(), ctx); | |
1772 | return; | |
1773 | } | |
1774 | ||
19c5870c | 1775 | DPRINT(("on CPU%d forcing system wide stop for [%d]\n", smp_processor_id(), task_pid_nr(ctx->ctx_task))); |
1da177e4 LT |
1776 | /* |
1777 | * the context is already protected in pfm_close(), we simply | |
1778 | * need to mask interrupts to avoid a PMU interrupt race on | |
1779 | * this CPU | |
1780 | */ | |
1781 | local_irq_save(flags); | |
1782 | ||
1783 | ret = pfm_context_unload(ctx, NULL, 0, regs); | |
1784 | if (ret) { | |
1785 | DPRINT(("context_unload returned %d\n", ret)); | |
1786 | } | |
1787 | ||
1788 | /* | |
1789 | * unmask interrupts, PMU interrupts are now spurious here | |
1790 | */ | |
1791 | local_irq_restore(flags); | |
1792 | } | |
1793 | ||
1794 | static void | |
1795 | pfm_syswide_cleanup_other_cpu(pfm_context_t *ctx) | |
1796 | { | |
1797 | int ret; | |
1798 | ||
1799 | DPRINT(("calling CPU%d for cleanup\n", ctx->ctx_cpu)); | |
8691e5a8 | 1800 | ret = smp_call_function_single(ctx->ctx_cpu, pfm_syswide_force_stop, ctx, 1); |
1da177e4 LT |
1801 | DPRINT(("called CPU%d for cleanup ret=%d\n", ctx->ctx_cpu, ret)); |
1802 | } | |
1803 | #endif /* CONFIG_SMP */ | |
1804 | ||
1805 | /* | |
1806 | * called for each close(). Partially free resources. | |
1807 | * When caller is self-monitoring, the context is unloaded. | |
1808 | */ | |
1809 | static int | |
75e1fcc0 | 1810 | pfm_flush(struct file *filp, fl_owner_t id) |
1da177e4 LT |
1811 | { |
1812 | pfm_context_t *ctx; | |
1813 | struct task_struct *task; | |
1814 | struct pt_regs *regs; | |
1815 | unsigned long flags; | |
1816 | unsigned long smpl_buf_size = 0UL; | |
1817 | void *smpl_buf_vaddr = NULL; | |
1818 | int state, is_system; | |
1819 | ||
1820 | if (PFM_IS_FILE(filp) == 0) { | |
1821 | DPRINT(("bad magic for\n")); | |
1822 | return -EBADF; | |
1823 | } | |
1824 | ||
df0a59a1 | 1825 | ctx = filp->private_data; |
1da177e4 | 1826 | if (ctx == NULL) { |
19c5870c | 1827 | printk(KERN_ERR "perfmon: pfm_flush: NULL ctx [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1828 | return -EBADF; |
1829 | } | |
1830 | ||
1831 | /* | |
1832 | * remove our file from the async queue, if we use this mode. | |
1833 | * This can be done without the context being protected. We come | |
72fdbdce | 1834 | * here when the context has become unreachable by other tasks. |
1da177e4 LT |
1835 | * |
1836 | * We may still have active monitoring at this point and we may | |
1837 | * end up in pfm_overflow_handler(). However, fasync_helper() | |
1838 | * operates with interrupts disabled and it cleans up the | |
1839 | * queue. If the PMU handler is called prior to entering | |
1840 | * fasync_helper() then it will send a signal. If it is | |
1841 | * invoked after, it will find an empty queue and no | |
1842 | * signal will be sent. In both case, we are safe | |
1843 | */ | |
1da177e4 LT |
1844 | PROTECT_CTX(ctx, flags); |
1845 | ||
1846 | state = ctx->ctx_state; | |
1847 | is_system = ctx->ctx_fl_system; | |
1848 | ||
1849 | task = PFM_CTX_TASK(ctx); | |
6450578f | 1850 | regs = task_pt_regs(task); |
1da177e4 LT |
1851 | |
1852 | DPRINT(("ctx_state=%d is_current=%d\n", | |
1853 | state, | |
1854 | task == current ? 1 : 0)); | |
1855 | ||
1856 | /* | |
1857 | * if state == UNLOADED, then task is NULL | |
1858 | */ | |
1859 | ||
1860 | /* | |
1861 | * we must stop and unload because we are losing access to the context. | |
1862 | */ | |
1863 | if (task == current) { | |
1864 | #ifdef CONFIG_SMP | |
1865 | /* | |
1866 | * the task IS the owner but it migrated to another CPU: that's bad | |
1867 | * but we must handle this cleanly. Unfortunately, the kernel does | |
1868 | * not provide a mechanism to block migration (while the context is loaded). | |
1869 | * | |
1870 | * We need to release the resource on the ORIGINAL cpu. | |
1871 | */ | |
1872 | if (is_system && ctx->ctx_cpu != smp_processor_id()) { | |
1873 | ||
1874 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
1875 | /* | |
1876 | * keep context protected but unmask interrupt for IPI | |
1877 | */ | |
1878 | local_irq_restore(flags); | |
1879 | ||
1880 | pfm_syswide_cleanup_other_cpu(ctx); | |
1881 | ||
1882 | /* | |
1883 | * restore interrupt masking | |
1884 | */ | |
1885 | local_irq_save(flags); | |
1886 | ||
1887 | /* | |
1888 | * context is unloaded at this point | |
1889 | */ | |
1890 | } else | |
1891 | #endif /* CONFIG_SMP */ | |
1892 | { | |
1893 | ||
1894 | DPRINT(("forcing unload\n")); | |
1895 | /* | |
1896 | * stop and unload, returning with state UNLOADED | |
1897 | * and session unreserved. | |
1898 | */ | |
1899 | pfm_context_unload(ctx, NULL, 0, regs); | |
1900 | ||
1901 | DPRINT(("ctx_state=%d\n", ctx->ctx_state)); | |
1902 | } | |
1903 | } | |
1904 | ||
1905 | /* | |
1906 | * remove virtual mapping, if any, for the calling task. | |
1907 | * cannot reset ctx field until last user is calling close(). | |
1908 | * | |
1909 | * ctx_smpl_vaddr must never be cleared because it is needed | |
1910 | * by every task with access to the context | |
1911 | * | |
1912 | * When called from do_exit(), the mm context is gone already, therefore | |
1913 | * mm is NULL, i.e., the VMA is already gone and we do not have to | |
1914 | * do anything here | |
1915 | */ | |
1916 | if (ctx->ctx_smpl_vaddr && current->mm) { | |
1917 | smpl_buf_vaddr = ctx->ctx_smpl_vaddr; | |
1918 | smpl_buf_size = ctx->ctx_smpl_size; | |
1919 | } | |
1920 | ||
1921 | UNPROTECT_CTX(ctx, flags); | |
1922 | ||
1923 | /* | |
1924 | * if there was a mapping, then we systematically remove it | |
1925 | * at this point. Cannot be done inside critical section | |
1926 | * because some VM function reenables interrupts. | |
1927 | * | |
1928 | */ | |
9f3a4afb | 1929 | if (smpl_buf_vaddr) pfm_remove_smpl_mapping(smpl_buf_vaddr, smpl_buf_size); |
1da177e4 LT |
1930 | |
1931 | return 0; | |
1932 | } | |
1933 | /* | |
1934 | * called either on explicit close() or from exit_files(). | |
1935 | * Only the LAST user of the file gets to this point, i.e., it is | |
1936 | * called only ONCE. | |
1937 | * | |
1938 | * IMPORTANT: we get called ONLY when the refcnt on the file gets to zero | |
1939 | * (fput()),i.e, last task to access the file. Nobody else can access the | |
1940 | * file at this point. | |
1941 | * | |
1942 | * When called from exit_files(), the VMA has been freed because exit_mm() | |
1943 | * is executed before exit_files(). | |
1944 | * | |
1945 | * When called from exit_files(), the current task is not yet ZOMBIE but we | |
1946 | * flush the PMU state to the context. | |
1947 | */ | |
1948 | static int | |
1949 | pfm_close(struct inode *inode, struct file *filp) | |
1950 | { | |
1951 | pfm_context_t *ctx; | |
1952 | struct task_struct *task; | |
1953 | struct pt_regs *regs; | |
1954 | DECLARE_WAITQUEUE(wait, current); | |
1955 | unsigned long flags; | |
1956 | unsigned long smpl_buf_size = 0UL; | |
1957 | void *smpl_buf_addr = NULL; | |
1958 | int free_possible = 1; | |
1959 | int state, is_system; | |
1960 | ||
1961 | DPRINT(("pfm_close called private=%p\n", filp->private_data)); | |
1962 | ||
1963 | if (PFM_IS_FILE(filp) == 0) { | |
1964 | DPRINT(("bad magic\n")); | |
1965 | return -EBADF; | |
1966 | } | |
1967 | ||
df0a59a1 | 1968 | ctx = filp->private_data; |
1da177e4 | 1969 | if (ctx == NULL) { |
19c5870c | 1970 | printk(KERN_ERR "perfmon: pfm_close: NULL ctx [%d]\n", task_pid_nr(current)); |
1da177e4 LT |
1971 | return -EBADF; |
1972 | } | |
1973 | ||
1974 | PROTECT_CTX(ctx, flags); | |
1975 | ||
1976 | state = ctx->ctx_state; | |
1977 | is_system = ctx->ctx_fl_system; | |
1978 | ||
1979 | task = PFM_CTX_TASK(ctx); | |
6450578f | 1980 | regs = task_pt_regs(task); |
1da177e4 LT |
1981 | |
1982 | DPRINT(("ctx_state=%d is_current=%d\n", | |
1983 | state, | |
1984 | task == current ? 1 : 0)); | |
1985 | ||
1986 | /* | |
1987 | * if task == current, then pfm_flush() unloaded the context | |
1988 | */ | |
1989 | if (state == PFM_CTX_UNLOADED) goto doit; | |
1990 | ||
1991 | /* | |
1992 | * context is loaded/masked and task != current, we need to | |
1993 | * either force an unload or go zombie | |
1994 | */ | |
1995 | ||
1996 | /* | |
1997 | * The task is currently blocked or will block after an overflow. | |
1998 | * we must force it to wakeup to get out of the | |
1999 | * MASKED state and transition to the unloaded state by itself. | |
2000 | * | |
2001 | * This situation is only possible for per-task mode | |
2002 | */ | |
2003 | if (state == PFM_CTX_MASKED && CTX_OVFL_NOBLOCK(ctx) == 0) { | |
2004 | ||
2005 | /* | |
2006 | * set a "partial" zombie state to be checked | |
2007 | * upon return from down() in pfm_handle_work(). | |
2008 | * | |
2009 | * We cannot use the ZOMBIE state, because it is checked | |
2010 | * by pfm_load_regs() which is called upon wakeup from down(). | |
2011 | * In such case, it would free the context and then we would | |
2012 | * return to pfm_handle_work() which would access the | |
2013 | * stale context. Instead, we set a flag invisible to pfm_load_regs() | |
2014 | * but visible to pfm_handle_work(). | |
2015 | * | |
2016 | * For some window of time, we have a zombie context with | |
2017 | * ctx_state = MASKED and not ZOMBIE | |
2018 | */ | |
2019 | ctx->ctx_fl_going_zombie = 1; | |
2020 | ||
2021 | /* | |
2022 | * force task to wake up from MASKED state | |
2023 | */ | |
60f1c444 | 2024 | complete(&ctx->ctx_restart_done); |
1da177e4 LT |
2025 | |
2026 | DPRINT(("waking up ctx_state=%d\n", state)); | |
2027 | ||
2028 | /* | |
2029 | * put ourself to sleep waiting for the other | |
2030 | * task to report completion | |
2031 | * | |
2032 | * the context is protected by mutex, therefore there | |
2033 | * is no risk of being notified of completion before | |
2034 | * begin actually on the waitq. | |
2035 | */ | |
2036 | set_current_state(TASK_INTERRUPTIBLE); | |
2037 | add_wait_queue(&ctx->ctx_zombieq, &wait); | |
2038 | ||
2039 | UNPROTECT_CTX(ctx, flags); | |
2040 | ||
2041 | /* | |
2042 | * XXX: check for signals : | |
2043 | * - ok for explicit close | |
2044 | * - not ok when coming from exit_files() | |
2045 | */ | |
2046 | schedule(); | |
2047 | ||
2048 | ||
2049 | PROTECT_CTX(ctx, flags); | |
2050 | ||
2051 | ||
2052 | remove_wait_queue(&ctx->ctx_zombieq, &wait); | |
2053 | set_current_state(TASK_RUNNING); | |
2054 | ||
2055 | /* | |
2056 | * context is unloaded at this point | |
2057 | */ | |
2058 | DPRINT(("after zombie wakeup ctx_state=%d for\n", state)); | |
2059 | } | |
2060 | else if (task != current) { | |
2061 | #ifdef CONFIG_SMP | |
2062 | /* | |
2063 | * switch context to zombie state | |
2064 | */ | |
2065 | ctx->ctx_state = PFM_CTX_ZOMBIE; | |
2066 | ||
19c5870c | 2067 | DPRINT(("zombie ctx for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
2068 | /* |
2069 | * cannot free the context on the spot. deferred until | |
2070 | * the task notices the ZOMBIE state | |
2071 | */ | |
2072 | free_possible = 0; | |
2073 | #else | |
2074 | pfm_context_unload(ctx, NULL, 0, regs); | |
2075 | #endif | |
2076 | } | |
2077 | ||
2078 | doit: | |
2079 | /* reload state, may have changed during opening of critical section */ | |
2080 | state = ctx->ctx_state; | |
2081 | ||
2082 | /* | |
2083 | * the context is still attached to a task (possibly current) | |
2084 | * we cannot destroy it right now | |
2085 | */ | |
2086 | ||
2087 | /* | |
2088 | * we must free the sampling buffer right here because | |
2089 | * we cannot rely on it being cleaned up later by the | |
2090 | * monitored task. It is not possible to free vmalloc'ed | |
2091 | * memory in pfm_load_regs(). Instead, we remove the buffer | |
2092 | * now. should there be subsequent PMU overflow originally | |
2093 | * meant for sampling, the will be converted to spurious | |
2094 | * and that's fine because the monitoring tools is gone anyway. | |
2095 | */ | |
2096 | if (ctx->ctx_smpl_hdr) { | |
2097 | smpl_buf_addr = ctx->ctx_smpl_hdr; | |
2098 | smpl_buf_size = ctx->ctx_smpl_size; | |
2099 | /* no more sampling */ | |
2100 | ctx->ctx_smpl_hdr = NULL; | |
2101 | ctx->ctx_fl_is_sampling = 0; | |
2102 | } | |
2103 | ||
2104 | DPRINT(("ctx_state=%d free_possible=%d addr=%p size=%lu\n", | |
2105 | state, | |
2106 | free_possible, | |
2107 | smpl_buf_addr, | |
2108 | smpl_buf_size)); | |
2109 | ||
2110 | if (smpl_buf_addr) pfm_exit_smpl_buffer(ctx->ctx_buf_fmt); | |
2111 | ||
2112 | /* | |
2113 | * UNLOADED that the session has already been unreserved. | |
2114 | */ | |
2115 | if (state == PFM_CTX_ZOMBIE) { | |
2116 | pfm_unreserve_session(ctx, ctx->ctx_fl_system , ctx->ctx_cpu); | |
2117 | } | |
2118 | ||
2119 | /* | |
2120 | * disconnect file descriptor from context must be done | |
2121 | * before we unlock. | |
2122 | */ | |
2123 | filp->private_data = NULL; | |
2124 | ||
2125 | /* | |
72fdbdce | 2126 | * if we free on the spot, the context is now completely unreachable |
1da177e4 LT |
2127 | * from the callers side. The monitored task side is also cut, so we |
2128 | * can freely cut. | |
2129 | * | |
2130 | * If we have a deferred free, only the caller side is disconnected. | |
2131 | */ | |
2132 | UNPROTECT_CTX(ctx, flags); | |
2133 | ||
2134 | /* | |
2135 | * All memory free operations (especially for vmalloc'ed memory) | |
2136 | * MUST be done with interrupts ENABLED. | |
2137 | */ | |
2138 | if (smpl_buf_addr) pfm_rvfree(smpl_buf_addr, smpl_buf_size); | |
2139 | ||
2140 | /* | |
2141 | * return the memory used by the context | |
2142 | */ | |
2143 | if (free_possible) pfm_context_free(ctx); | |
2144 | ||
2145 | return 0; | |
2146 | } | |
2147 | ||
2148 | static int | |
2149 | pfm_no_open(struct inode *irrelevant, struct file *dontcare) | |
2150 | { | |
2151 | DPRINT(("pfm_no_open called\n")); | |
2152 | return -ENXIO; | |
2153 | } | |
2154 | ||
2155 | ||
2156 | ||
5dfe4c96 | 2157 | static const struct file_operations pfm_file_ops = { |
ba58aebf AB |
2158 | .llseek = no_llseek, |
2159 | .read = pfm_read, | |
2160 | .write = pfm_write, | |
2161 | .poll = pfm_poll, | |
2162 | .unlocked_ioctl = pfm_ioctl, | |
2163 | .open = pfm_no_open, /* special open code to disallow open via /proc */ | |
2164 | .fasync = pfm_fasync, | |
2165 | .release = pfm_close, | |
2166 | .flush = pfm_flush | |
1da177e4 LT |
2167 | }; |
2168 | ||
7ae6bdbd MS |
2169 | static char *pfmfs_dname(struct dentry *dentry, char *buffer, int buflen) |
2170 | { | |
2171 | return dynamic_dname(dentry, buffer, buflen, "pfm:[%lu]", | |
2172 | dentry->d_inode->i_ino); | |
2173 | } | |
2174 | ||
3ba13d17 | 2175 | static const struct dentry_operations pfmfs_dentry_operations = { |
b26d4cd3 | 2176 | .d_delete = always_delete_dentry, |
7ae6bdbd | 2177 | .d_dname = pfmfs_dname, |
1da177e4 LT |
2178 | }; |
2179 | ||
2180 | ||
f8e811b9 AV |
2181 | static struct file * |
2182 | pfm_alloc_file(pfm_context_t *ctx) | |
1da177e4 | 2183 | { |
f8e811b9 AV |
2184 | struct file *file; |
2185 | struct inode *inode; | |
2c48b9c4 | 2186 | struct path path; |
7ae6bdbd | 2187 | struct qstr this = { .name = "" }; |
1da177e4 | 2188 | |
1da177e4 LT |
2189 | /* |
2190 | * allocate a new inode | |
2191 | */ | |
2192 | inode = new_inode(pfmfs_mnt->mnt_sb); | |
f8e811b9 AV |
2193 | if (!inode) |
2194 | return ERR_PTR(-ENOMEM); | |
1da177e4 LT |
2195 | |
2196 | DPRINT(("new inode ino=%ld @%p\n", inode->i_ino, inode)); | |
2197 | ||
2198 | inode->i_mode = S_IFCHR|S_IRUGO; | |
ef81ee98 DH |
2199 | inode->i_uid = current_fsuid(); |
2200 | inode->i_gid = current_fsgid(); | |
1da177e4 | 2201 | |
1da177e4 LT |
2202 | /* |
2203 | * allocate a new dcache entry | |
2204 | */ | |
4c1d5a64 | 2205 | path.dentry = d_alloc(pfmfs_mnt->mnt_root, &this); |
2c48b9c4 | 2206 | if (!path.dentry) { |
f8e811b9 AV |
2207 | iput(inode); |
2208 | return ERR_PTR(-ENOMEM); | |
2209 | } | |
2c48b9c4 | 2210 | path.mnt = mntget(pfmfs_mnt); |
1da177e4 | 2211 | |
2c48b9c4 | 2212 | d_add(path.dentry, inode); |
1da177e4 | 2213 | |
2c48b9c4 | 2214 | file = alloc_file(&path, FMODE_READ, &pfm_file_ops); |
39b65252 | 2215 | if (IS_ERR(file)) { |
2c48b9c4 | 2216 | path_put(&path); |
39b65252 | 2217 | return file; |
f8e811b9 | 2218 | } |
1da177e4 | 2219 | |
1da177e4 | 2220 | file->f_flags = O_RDONLY; |
f8e811b9 | 2221 | file->private_data = ctx; |
1da177e4 | 2222 | |
f8e811b9 | 2223 | return file; |
1da177e4 LT |
2224 | } |
2225 | ||
2226 | static int | |
2227 | pfm_remap_buffer(struct vm_area_struct *vma, unsigned long buf, unsigned long addr, unsigned long size) | |
2228 | { | |
2229 | DPRINT(("CPU%d buf=0x%lx addr=0x%lx size=%ld\n", smp_processor_id(), buf, addr, size)); | |
2230 | ||
2231 | while (size > 0) { | |
2232 | unsigned long pfn = ia64_tpa(buf) >> PAGE_SHIFT; | |
2233 | ||
2234 | ||
2235 | if (remap_pfn_range(vma, addr, pfn, PAGE_SIZE, PAGE_READONLY)) | |
2236 | return -ENOMEM; | |
2237 | ||
2238 | addr += PAGE_SIZE; | |
2239 | buf += PAGE_SIZE; | |
2240 | size -= PAGE_SIZE; | |
2241 | } | |
2242 | return 0; | |
2243 | } | |
2244 | ||
2245 | /* | |
2246 | * allocate a sampling buffer and remaps it into the user address space of the task | |
2247 | */ | |
2248 | static int | |
41d5e5d7 | 2249 | pfm_smpl_buffer_alloc(struct task_struct *task, struct file *filp, pfm_context_t *ctx, unsigned long rsize, void **user_vaddr) |
1da177e4 LT |
2250 | { |
2251 | struct mm_struct *mm = task->mm; | |
2252 | struct vm_area_struct *vma = NULL; | |
2253 | unsigned long size; | |
2254 | void *smpl_buf; | |
2255 | ||
2256 | ||
2257 | /* | |
2258 | * the fixed header + requested size and align to page boundary | |
2259 | */ | |
2260 | size = PAGE_ALIGN(rsize); | |
2261 | ||
2262 | DPRINT(("sampling buffer rsize=%lu size=%lu bytes\n", rsize, size)); | |
2263 | ||
2264 | /* | |
2265 | * check requested size to avoid Denial-of-service attacks | |
2266 | * XXX: may have to refine this test | |
2267 | * Check against address space limit. | |
2268 | * | |
2269 | * if ((mm->total_vm << PAGE_SHIFT) + len> task->rlim[RLIMIT_AS].rlim_cur) | |
2270 | * return -ENOMEM; | |
2271 | */ | |
02b763b8 | 2272 | if (size > task_rlimit(task, RLIMIT_MEMLOCK)) |
1da177e4 LT |
2273 | return -ENOMEM; |
2274 | ||
2275 | /* | |
2276 | * We do the easy to undo allocations first. | |
2277 | * | |
2278 | * pfm_rvmalloc(), clears the buffer, so there is no leak | |
2279 | */ | |
2280 | smpl_buf = pfm_rvmalloc(size); | |
2281 | if (smpl_buf == NULL) { | |
2282 | DPRINT(("Can't allocate sampling buffer\n")); | |
2283 | return -ENOMEM; | |
2284 | } | |
2285 | ||
2286 | DPRINT(("smpl_buf @%p\n", smpl_buf)); | |
2287 | ||
2288 | /* allocate vma */ | |
c3762229 | 2289 | vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL); |
1da177e4 LT |
2290 | if (!vma) { |
2291 | DPRINT(("Cannot allocate vma\n")); | |
2292 | goto error_kmem; | |
2293 | } | |
5beb4930 | 2294 | INIT_LIST_HEAD(&vma->anon_vma_chain); |
1da177e4 LT |
2295 | |
2296 | /* | |
2297 | * partially initialize the vma for the sampling buffer | |
2298 | */ | |
2299 | vma->vm_mm = mm; | |
cb0942b8 | 2300 | vma->vm_file = get_file(filp); |
314e51b9 | 2301 | vma->vm_flags = VM_READ|VM_MAYREAD|VM_DONTEXPAND|VM_DONTDUMP; |
1da177e4 LT |
2302 | vma->vm_page_prot = PAGE_READONLY; /* XXX may need to change */ |
2303 | ||
2304 | /* | |
2305 | * Now we have everything we need and we can initialize | |
2306 | * and connect all the data structures | |
2307 | */ | |
2308 | ||
2309 | ctx->ctx_smpl_hdr = smpl_buf; | |
2310 | ctx->ctx_smpl_size = size; /* aligned size */ | |
2311 | ||
2312 | /* | |
2313 | * Let's do the difficult operations next. | |
2314 | * | |
2315 | * now we atomically find some area in the address space and | |
2316 | * remap the buffer in it. | |
2317 | */ | |
2318 | down_write(&task->mm->mmap_sem); | |
2319 | ||
2320 | /* find some free area in address space, must have mmap sem held */ | |
4ad310b8 AV |
2321 | vma->vm_start = get_unmapped_area(NULL, 0, size, 0, MAP_PRIVATE|MAP_ANONYMOUS); |
2322 | if (IS_ERR_VALUE(vma->vm_start)) { | |
1da177e4 LT |
2323 | DPRINT(("Cannot find unmapped area for size %ld\n", size)); |
2324 | up_write(&task->mm->mmap_sem); | |
2325 | goto error; | |
2326 | } | |
2327 | vma->vm_end = vma->vm_start + size; | |
2328 | vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT; | |
2329 | ||
2330 | DPRINT(("aligned size=%ld, hdr=%p mapped @0x%lx\n", size, ctx->ctx_smpl_hdr, vma->vm_start)); | |
2331 | ||
2332 | /* can only be applied to current task, need to have the mm semaphore held when called */ | |
2333 | if (pfm_remap_buffer(vma, (unsigned long)smpl_buf, vma->vm_start, size)) { | |
2334 | DPRINT(("Can't remap buffer\n")); | |
2335 | up_write(&task->mm->mmap_sem); | |
2336 | goto error; | |
2337 | } | |
2338 | ||
2339 | /* | |
2340 | * now insert the vma in the vm list for the process, must be | |
2341 | * done with mmap lock held | |
2342 | */ | |
2343 | insert_vm_struct(mm, vma); | |
2344 | ||
ab50b8ed HD |
2345 | vm_stat_account(vma->vm_mm, vma->vm_flags, vma->vm_file, |
2346 | vma_pages(vma)); | |
1da177e4 LT |
2347 | up_write(&task->mm->mmap_sem); |
2348 | ||
2349 | /* | |
2350 | * keep track of user level virtual address | |
2351 | */ | |
2352 | ctx->ctx_smpl_vaddr = (void *)vma->vm_start; | |
2353 | *(unsigned long *)user_vaddr = vma->vm_start; | |
2354 | ||
2355 | return 0; | |
2356 | ||
2357 | error: | |
2358 | kmem_cache_free(vm_area_cachep, vma); | |
2359 | error_kmem: | |
2360 | pfm_rvfree(smpl_buf, size); | |
2361 | ||
2362 | return -ENOMEM; | |
2363 | } | |
2364 | ||
2365 | /* | |
2366 | * XXX: do something better here | |
2367 | */ | |
2368 | static int | |
2369 | pfm_bad_permissions(struct task_struct *task) | |
2370 | { | |
c69e8d9c | 2371 | const struct cred *tcred; |
6c1ee033 EB |
2372 | kuid_t uid = current_uid(); |
2373 | kgid_t gid = current_gid(); | |
c69e8d9c DH |
2374 | int ret; |
2375 | ||
2376 | rcu_read_lock(); | |
2377 | tcred = __task_cred(task); | |
ef81ee98 | 2378 | |
1da177e4 LT |
2379 | /* inspired by ptrace_attach() */ |
2380 | DPRINT(("cur: uid=%d gid=%d task: euid=%d suid=%d uid=%d egid=%d sgid=%d\n", | |
6c1ee033 EB |
2381 | from_kuid(&init_user_ns, uid), |
2382 | from_kgid(&init_user_ns, gid), | |
2383 | from_kuid(&init_user_ns, tcred->euid), | |
2384 | from_kuid(&init_user_ns, tcred->suid), | |
2385 | from_kuid(&init_user_ns, tcred->uid), | |
2386 | from_kgid(&init_user_ns, tcred->egid), | |
2387 | from_kgid(&init_user_ns, tcred->sgid))); | |
2388 | ||
2389 | ret = ((!uid_eq(uid, tcred->euid)) | |
2390 | || (!uid_eq(uid, tcred->suid)) | |
2391 | || (!uid_eq(uid, tcred->uid)) | |
2392 | || (!gid_eq(gid, tcred->egid)) | |
2393 | || (!gid_eq(gid, tcred->sgid)) | |
2394 | || (!gid_eq(gid, tcred->gid))) && !capable(CAP_SYS_PTRACE); | |
c69e8d9c DH |
2395 | |
2396 | rcu_read_unlock(); | |
2397 | return ret; | |
1da177e4 LT |
2398 | } |
2399 | ||
2400 | static int | |
2401 | pfarg_is_sane(struct task_struct *task, pfarg_context_t *pfx) | |
2402 | { | |
2403 | int ctx_flags; | |
2404 | ||
2405 | /* valid signal */ | |
2406 | ||
2407 | ctx_flags = pfx->ctx_flags; | |
2408 | ||
2409 | if (ctx_flags & PFM_FL_SYSTEM_WIDE) { | |
2410 | ||
2411 | /* | |
2412 | * cannot block in this mode | |
2413 | */ | |
2414 | if (ctx_flags & PFM_FL_NOTIFY_BLOCK) { | |
2415 | DPRINT(("cannot use blocking mode when in system wide monitoring\n")); | |
2416 | return -EINVAL; | |
2417 | } | |
2418 | } else { | |
2419 | } | |
2420 | /* probably more to add here */ | |
2421 | ||
2422 | return 0; | |
2423 | } | |
2424 | ||
2425 | static int | |
41d5e5d7 | 2426 | pfm_setup_buffer_fmt(struct task_struct *task, struct file *filp, pfm_context_t *ctx, unsigned int ctx_flags, |
1da177e4 LT |
2427 | unsigned int cpu, pfarg_context_t *arg) |
2428 | { | |
2429 | pfm_buffer_fmt_t *fmt = NULL; | |
2430 | unsigned long size = 0UL; | |
2431 | void *uaddr = NULL; | |
2432 | void *fmt_arg = NULL; | |
2433 | int ret = 0; | |
2434 | #define PFM_CTXARG_BUF_ARG(a) (pfm_buffer_fmt_t *)(a+1) | |
2435 | ||
2436 | /* invoke and lock buffer format, if found */ | |
2437 | fmt = pfm_find_buffer_fmt(arg->ctx_smpl_buf_id); | |
2438 | if (fmt == NULL) { | |
19c5870c | 2439 | DPRINT(("[%d] cannot find buffer format\n", task_pid_nr(task))); |
1da177e4 LT |
2440 | return -EINVAL; |
2441 | } | |
2442 | ||
2443 | /* | |
2444 | * buffer argument MUST be contiguous to pfarg_context_t | |
2445 | */ | |
2446 | if (fmt->fmt_arg_size) fmt_arg = PFM_CTXARG_BUF_ARG(arg); | |
2447 | ||
2448 | ret = pfm_buf_fmt_validate(fmt, task, ctx_flags, cpu, fmt_arg); | |
2449 | ||
19c5870c | 2450 | DPRINT(("[%d] after validate(0x%x,%d,%p)=%d\n", task_pid_nr(task), ctx_flags, cpu, fmt_arg, ret)); |
1da177e4 LT |
2451 | |
2452 | if (ret) goto error; | |
2453 | ||
2454 | /* link buffer format and context */ | |
2455 | ctx->ctx_buf_fmt = fmt; | |
f8e811b9 | 2456 | ctx->ctx_fl_is_sampling = 1; /* assume record() is defined */ |
1da177e4 LT |
2457 | |
2458 | /* | |
2459 | * check if buffer format wants to use perfmon buffer allocation/mapping service | |
2460 | */ | |
2461 | ret = pfm_buf_fmt_getsize(fmt, task, ctx_flags, cpu, fmt_arg, &size); | |
2462 | if (ret) goto error; | |
2463 | ||
2464 | if (size) { | |
2465 | /* | |
2466 | * buffer is always remapped into the caller's address space | |
2467 | */ | |
41d5e5d7 | 2468 | ret = pfm_smpl_buffer_alloc(current, filp, ctx, size, &uaddr); |
1da177e4 LT |
2469 | if (ret) goto error; |
2470 | ||
2471 | /* keep track of user address of buffer */ | |
2472 | arg->ctx_smpl_vaddr = uaddr; | |
2473 | } | |
2474 | ret = pfm_buf_fmt_init(fmt, task, ctx->ctx_smpl_hdr, ctx_flags, cpu, fmt_arg); | |
2475 | ||
2476 | error: | |
2477 | return ret; | |
2478 | } | |
2479 | ||
2480 | static void | |
2481 | pfm_reset_pmu_state(pfm_context_t *ctx) | |
2482 | { | |
2483 | int i; | |
2484 | ||
2485 | /* | |
2486 | * install reset values for PMC. | |
2487 | */ | |
2488 | for (i=1; PMC_IS_LAST(i) == 0; i++) { | |
2489 | if (PMC_IS_IMPL(i) == 0) continue; | |
2490 | ctx->ctx_pmcs[i] = PMC_DFL_VAL(i); | |
2491 | DPRINT(("pmc[%d]=0x%lx\n", i, ctx->ctx_pmcs[i])); | |
2492 | } | |
2493 | /* | |
2494 | * PMD registers are set to 0UL when the context in memset() | |
2495 | */ | |
2496 | ||
2497 | /* | |
2498 | * On context switched restore, we must restore ALL pmc and ALL pmd even | |
2499 | * when they are not actively used by the task. In UP, the incoming process | |
2500 | * may otherwise pick up left over PMC, PMD state from the previous process. | |
2501 | * As opposed to PMD, stale PMC can cause harm to the incoming | |
2502 | * process because they may change what is being measured. | |
2503 | * Therefore, we must systematically reinstall the entire | |
2504 | * PMC state. In SMP, the same thing is possible on the | |
2505 | * same CPU but also on between 2 CPUs. | |
2506 | * | |
2507 | * The problem with PMD is information leaking especially | |
2508 | * to user level when psr.sp=0 | |
2509 | * | |
2510 | * There is unfortunately no easy way to avoid this problem | |
2511 | * on either UP or SMP. This definitively slows down the | |
2512 | * pfm_load_regs() function. | |
2513 | */ | |
2514 | ||
2515 | /* | |
2516 | * bitmask of all PMCs accessible to this context | |
2517 | * | |
2518 | * PMC0 is treated differently. | |
2519 | */ | |
2520 | ctx->ctx_all_pmcs[0] = pmu_conf->impl_pmcs[0] & ~0x1; | |
2521 | ||
2522 | /* | |
72fdbdce | 2523 | * bitmask of all PMDs that are accessible to this context |
1da177e4 LT |
2524 | */ |
2525 | ctx->ctx_all_pmds[0] = pmu_conf->impl_pmds[0]; | |
2526 | ||
2527 | DPRINT(("<%d> all_pmcs=0x%lx all_pmds=0x%lx\n", ctx->ctx_fd, ctx->ctx_all_pmcs[0],ctx->ctx_all_pmds[0])); | |
2528 | ||
2529 | /* | |
2530 | * useful in case of re-enable after disable | |
2531 | */ | |
2532 | ctx->ctx_used_ibrs[0] = 0UL; | |
2533 | ctx->ctx_used_dbrs[0] = 0UL; | |
2534 | } | |
2535 | ||
2536 | static int | |
2537 | pfm_ctx_getsize(void *arg, size_t *sz) | |
2538 | { | |
2539 | pfarg_context_t *req = (pfarg_context_t *)arg; | |
2540 | pfm_buffer_fmt_t *fmt; | |
2541 | ||
2542 | *sz = 0; | |
2543 | ||
2544 | if (!pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) return 0; | |
2545 | ||
2546 | fmt = pfm_find_buffer_fmt(req->ctx_smpl_buf_id); | |
2547 | if (fmt == NULL) { | |
2548 | DPRINT(("cannot find buffer format\n")); | |
2549 | return -EINVAL; | |
2550 | } | |
2551 | /* get just enough to copy in user parameters */ | |
2552 | *sz = fmt->fmt_arg_size; | |
2553 | DPRINT(("arg_size=%lu\n", *sz)); | |
2554 | ||
2555 | return 0; | |
2556 | } | |
2557 | ||
2558 | ||
2559 | ||
2560 | /* | |
2561 | * cannot attach if : | |
2562 | * - kernel task | |
2563 | * - task not owned by caller | |
2564 | * - task incompatible with context mode | |
2565 | */ | |
2566 | static int | |
2567 | pfm_task_incompatible(pfm_context_t *ctx, struct task_struct *task) | |
2568 | { | |
2569 | /* | |
2570 | * no kernel task or task not owner by caller | |
2571 | */ | |
2572 | if (task->mm == NULL) { | |
19c5870c | 2573 | DPRINT(("task [%d] has not memory context (kernel thread)\n", task_pid_nr(task))); |
1da177e4 LT |
2574 | return -EPERM; |
2575 | } | |
2576 | if (pfm_bad_permissions(task)) { | |
19c5870c | 2577 | DPRINT(("no permission to attach to [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
2578 | return -EPERM; |
2579 | } | |
2580 | /* | |
2581 | * cannot block in self-monitoring mode | |
2582 | */ | |
2583 | if (CTX_OVFL_NOBLOCK(ctx) == 0 && task == current) { | |
19c5870c | 2584 | DPRINT(("cannot load a blocking context on self for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
2585 | return -EINVAL; |
2586 | } | |
2587 | ||
2588 | if (task->exit_state == EXIT_ZOMBIE) { | |
19c5870c | 2589 | DPRINT(("cannot attach to zombie task [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
2590 | return -EBUSY; |
2591 | } | |
2592 | ||
2593 | /* | |
2594 | * always ok for self | |
2595 | */ | |
2596 | if (task == current) return 0; | |
2597 | ||
21498223 | 2598 | if (!task_is_stopped_or_traced(task)) { |
19c5870c | 2599 | DPRINT(("cannot attach to non-stopped task [%d] state=%ld\n", task_pid_nr(task), task->state)); |
1da177e4 LT |
2600 | return -EBUSY; |
2601 | } | |
2602 | /* | |
2603 | * make sure the task is off any CPU | |
2604 | */ | |
85ba2d86 | 2605 | wait_task_inactive(task, 0); |
1da177e4 LT |
2606 | |
2607 | /* more to come... */ | |
2608 | ||
2609 | return 0; | |
2610 | } | |
2611 | ||
2612 | static int | |
2613 | pfm_get_task(pfm_context_t *ctx, pid_t pid, struct task_struct **task) | |
2614 | { | |
2615 | struct task_struct *p = current; | |
2616 | int ret; | |
2617 | ||
2618 | /* XXX: need to add more checks here */ | |
2619 | if (pid < 2) return -EPERM; | |
2620 | ||
e1b0d4ba | 2621 | if (pid != task_pid_vnr(current)) { |
1da177e4 LT |
2622 | |
2623 | read_lock(&tasklist_lock); | |
2624 | ||
e1b0d4ba | 2625 | p = find_task_by_vpid(pid); |
1da177e4 LT |
2626 | |
2627 | /* make sure task cannot go away while we operate on it */ | |
2628 | if (p) get_task_struct(p); | |
2629 | ||
2630 | read_unlock(&tasklist_lock); | |
2631 | ||
2632 | if (p == NULL) return -ESRCH; | |
2633 | } | |
2634 | ||
2635 | ret = pfm_task_incompatible(ctx, p); | |
2636 | if (ret == 0) { | |
2637 | *task = p; | |
2638 | } else if (p != current) { | |
2639 | pfm_put_task(p); | |
2640 | } | |
2641 | return ret; | |
2642 | } | |
2643 | ||
2644 | ||
2645 | ||
2646 | static int | |
2647 | pfm_context_create(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
2648 | { | |
2649 | pfarg_context_t *req = (pfarg_context_t *)arg; | |
2650 | struct file *filp; | |
f8e811b9 | 2651 | struct path path; |
1da177e4 | 2652 | int ctx_flags; |
f8e811b9 | 2653 | int fd; |
1da177e4 LT |
2654 | int ret; |
2655 | ||
2656 | /* let's check the arguments first */ | |
2657 | ret = pfarg_is_sane(current, req); | |
f8e811b9 AV |
2658 | if (ret < 0) |
2659 | return ret; | |
1da177e4 LT |
2660 | |
2661 | ctx_flags = req->ctx_flags; | |
2662 | ||
2663 | ret = -ENOMEM; | |
2664 | ||
f8e811b9 AV |
2665 | fd = get_unused_fd(); |
2666 | if (fd < 0) | |
2667 | return fd; | |
1da177e4 | 2668 | |
f8e811b9 AV |
2669 | ctx = pfm_context_alloc(ctx_flags); |
2670 | if (!ctx) | |
2671 | goto error; | |
1da177e4 | 2672 | |
f8e811b9 AV |
2673 | filp = pfm_alloc_file(ctx); |
2674 | if (IS_ERR(filp)) { | |
2675 | ret = PTR_ERR(filp); | |
2676 | goto error_file; | |
2677 | } | |
1da177e4 | 2678 | |
f8e811b9 | 2679 | req->ctx_fd = ctx->ctx_fd = fd; |
1da177e4 LT |
2680 | |
2681 | /* | |
2682 | * does the user want to sample? | |
2683 | */ | |
2684 | if (pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) { | |
41d5e5d7 | 2685 | ret = pfm_setup_buffer_fmt(current, filp, ctx, ctx_flags, 0, req); |
f8e811b9 AV |
2686 | if (ret) |
2687 | goto buffer_error; | |
1da177e4 LT |
2688 | } |
2689 | ||
04157e4c | 2690 | DPRINT(("ctx=%p flags=0x%x system=%d notify_block=%d excl_idle=%d no_msg=%d ctx_fd=%d\n", |
1da177e4 LT |
2691 | ctx, |
2692 | ctx_flags, | |
2693 | ctx->ctx_fl_system, | |
2694 | ctx->ctx_fl_block, | |
2695 | ctx->ctx_fl_excl_idle, | |
2696 | ctx->ctx_fl_no_msg, | |
2697 | ctx->ctx_fd)); | |
2698 | ||
2699 | /* | |
2700 | * initialize soft PMU state | |
2701 | */ | |
2702 | pfm_reset_pmu_state(ctx); | |
2703 | ||
f8e811b9 AV |
2704 | fd_install(fd, filp); |
2705 | ||
1da177e4 LT |
2706 | return 0; |
2707 | ||
2708 | buffer_error: | |
f8e811b9 AV |
2709 | path = filp->f_path; |
2710 | put_filp(filp); | |
2711 | path_put(&path); | |
1da177e4 LT |
2712 | |
2713 | if (ctx->ctx_buf_fmt) { | |
2714 | pfm_buf_fmt_exit(ctx->ctx_buf_fmt, current, NULL, regs); | |
2715 | } | |
2716 | error_file: | |
2717 | pfm_context_free(ctx); | |
2718 | ||
2719 | error: | |
f8e811b9 | 2720 | put_unused_fd(fd); |
1da177e4 LT |
2721 | return ret; |
2722 | } | |
2723 | ||
2724 | static inline unsigned long | |
2725 | pfm_new_counter_value (pfm_counter_t *reg, int is_long_reset) | |
2726 | { | |
2727 | unsigned long val = is_long_reset ? reg->long_reset : reg->short_reset; | |
2728 | unsigned long new_seed, old_seed = reg->seed, mask = reg->mask; | |
2729 | extern unsigned long carta_random32 (unsigned long seed); | |
2730 | ||
2731 | if (reg->flags & PFM_REGFL_RANDOM) { | |
2732 | new_seed = carta_random32(old_seed); | |
2733 | val -= (old_seed & mask); /* counter values are negative numbers! */ | |
2734 | if ((mask >> 32) != 0) | |
2735 | /* construct a full 64-bit random value: */ | |
2736 | new_seed |= carta_random32(old_seed >> 32) << 32; | |
2737 | reg->seed = new_seed; | |
2738 | } | |
2739 | reg->lval = val; | |
2740 | return val; | |
2741 | } | |
2742 | ||
2743 | static void | |
2744 | pfm_reset_regs_masked(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset) | |
2745 | { | |
2746 | unsigned long mask = ovfl_regs[0]; | |
2747 | unsigned long reset_others = 0UL; | |
2748 | unsigned long val; | |
2749 | int i; | |
2750 | ||
2751 | /* | |
2752 | * now restore reset value on sampling overflowed counters | |
2753 | */ | |
2754 | mask >>= PMU_FIRST_COUNTER; | |
2755 | for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) { | |
2756 | ||
2757 | if ((mask & 0x1UL) == 0UL) continue; | |
2758 | ||
2759 | ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset); | |
2760 | reset_others |= ctx->ctx_pmds[i].reset_pmds[0]; | |
2761 | ||
2762 | DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val)); | |
2763 | } | |
2764 | ||
2765 | /* | |
2766 | * Now take care of resetting the other registers | |
2767 | */ | |
2768 | for(i = 0; reset_others; i++, reset_others >>= 1) { | |
2769 | ||
2770 | if ((reset_others & 0x1) == 0) continue; | |
2771 | ||
2772 | ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset); | |
2773 | ||
2774 | DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n", | |
2775 | is_long_reset ? "long" : "short", i, val)); | |
2776 | } | |
2777 | } | |
2778 | ||
2779 | static void | |
2780 | pfm_reset_regs(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset) | |
2781 | { | |
2782 | unsigned long mask = ovfl_regs[0]; | |
2783 | unsigned long reset_others = 0UL; | |
2784 | unsigned long val; | |
2785 | int i; | |
2786 | ||
2787 | DPRINT_ovfl(("ovfl_regs=0x%lx is_long_reset=%d\n", ovfl_regs[0], is_long_reset)); | |
2788 | ||
2789 | if (ctx->ctx_state == PFM_CTX_MASKED) { | |
2790 | pfm_reset_regs_masked(ctx, ovfl_regs, is_long_reset); | |
2791 | return; | |
2792 | } | |
2793 | ||
2794 | /* | |
2795 | * now restore reset value on sampling overflowed counters | |
2796 | */ | |
2797 | mask >>= PMU_FIRST_COUNTER; | |
2798 | for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) { | |
2799 | ||
2800 | if ((mask & 0x1UL) == 0UL) continue; | |
2801 | ||
2802 | val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset); | |
2803 | reset_others |= ctx->ctx_pmds[i].reset_pmds[0]; | |
2804 | ||
2805 | DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val)); | |
2806 | ||
2807 | pfm_write_soft_counter(ctx, i, val); | |
2808 | } | |
2809 | ||
2810 | /* | |
2811 | * Now take care of resetting the other registers | |
2812 | */ | |
2813 | for(i = 0; reset_others; i++, reset_others >>= 1) { | |
2814 | ||
2815 | if ((reset_others & 0x1) == 0) continue; | |
2816 | ||
2817 | val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset); | |
2818 | ||
2819 | if (PMD_IS_COUNTING(i)) { | |
2820 | pfm_write_soft_counter(ctx, i, val); | |
2821 | } else { | |
2822 | ia64_set_pmd(i, val); | |
2823 | } | |
2824 | DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n", | |
2825 | is_long_reset ? "long" : "short", i, val)); | |
2826 | } | |
2827 | ia64_srlz_d(); | |
2828 | } | |
2829 | ||
2830 | static int | |
2831 | pfm_write_pmcs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
2832 | { | |
1da177e4 LT |
2833 | struct task_struct *task; |
2834 | pfarg_reg_t *req = (pfarg_reg_t *)arg; | |
2835 | unsigned long value, pmc_pm; | |
2836 | unsigned long smpl_pmds, reset_pmds, impl_pmds; | |
2837 | unsigned int cnum, reg_flags, flags, pmc_type; | |
2838 | int i, can_access_pmu = 0, is_loaded, is_system, expert_mode; | |
2839 | int is_monitor, is_counting, state; | |
2840 | int ret = -EINVAL; | |
2841 | pfm_reg_check_t wr_func; | |
2842 | #define PFM_CHECK_PMC_PM(x, y, z) ((x)->ctx_fl_system ^ PMC_PM(y, z)) | |
2843 | ||
2844 | state = ctx->ctx_state; | |
2845 | is_loaded = state == PFM_CTX_LOADED ? 1 : 0; | |
2846 | is_system = ctx->ctx_fl_system; | |
2847 | task = ctx->ctx_task; | |
2848 | impl_pmds = pmu_conf->impl_pmds[0]; | |
2849 | ||
2850 | if (state == PFM_CTX_ZOMBIE) return -EINVAL; | |
2851 | ||
2852 | if (is_loaded) { | |
1da177e4 LT |
2853 | /* |
2854 | * In system wide and when the context is loaded, access can only happen | |
2855 | * when the caller is running on the CPU being monitored by the session. | |
2856 | * It does not have to be the owner (ctx_task) of the context per se. | |
2857 | */ | |
2858 | if (is_system && ctx->ctx_cpu != smp_processor_id()) { | |
2859 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
2860 | return -EBUSY; | |
2861 | } | |
2862 | can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; | |
2863 | } | |
2864 | expert_mode = pfm_sysctl.expert_mode; | |
2865 | ||
2866 | for (i = 0; i < count; i++, req++) { | |
2867 | ||
2868 | cnum = req->reg_num; | |
2869 | reg_flags = req->reg_flags; | |
2870 | value = req->reg_value; | |
2871 | smpl_pmds = req->reg_smpl_pmds[0]; | |
2872 | reset_pmds = req->reg_reset_pmds[0]; | |
2873 | flags = 0; | |
2874 | ||
2875 | ||
2876 | if (cnum >= PMU_MAX_PMCS) { | |
2877 | DPRINT(("pmc%u is invalid\n", cnum)); | |
2878 | goto error; | |
2879 | } | |
2880 | ||
2881 | pmc_type = pmu_conf->pmc_desc[cnum].type; | |
2882 | pmc_pm = (value >> pmu_conf->pmc_desc[cnum].pm_pos) & 0x1; | |
2883 | is_counting = (pmc_type & PFM_REG_COUNTING) == PFM_REG_COUNTING ? 1 : 0; | |
2884 | is_monitor = (pmc_type & PFM_REG_MONITOR) == PFM_REG_MONITOR ? 1 : 0; | |
2885 | ||
2886 | /* | |
2887 | * we reject all non implemented PMC as well | |
2888 | * as attempts to modify PMC[0-3] which are used | |
2889 | * as status registers by the PMU | |
2890 | */ | |
2891 | if ((pmc_type & PFM_REG_IMPL) == 0 || (pmc_type & PFM_REG_CONTROL) == PFM_REG_CONTROL) { | |
2892 | DPRINT(("pmc%u is unimplemented or no-access pmc_type=%x\n", cnum, pmc_type)); | |
2893 | goto error; | |
2894 | } | |
2895 | wr_func = pmu_conf->pmc_desc[cnum].write_check; | |
2896 | /* | |
2897 | * If the PMC is a monitor, then if the value is not the default: | |
2898 | * - system-wide session: PMCx.pm=1 (privileged monitor) | |
2899 | * - per-task : PMCx.pm=0 (user monitor) | |
2900 | */ | |
2901 | if (is_monitor && value != PMC_DFL_VAL(cnum) && is_system ^ pmc_pm) { | |
2902 | DPRINT(("pmc%u pmc_pm=%lu is_system=%d\n", | |
2903 | cnum, | |
2904 | pmc_pm, | |
2905 | is_system)); | |
2906 | goto error; | |
2907 | } | |
2908 | ||
2909 | if (is_counting) { | |
2910 | /* | |
2911 | * enforce generation of overflow interrupt. Necessary on all | |
2912 | * CPUs. | |
2913 | */ | |
2914 | value |= 1 << PMU_PMC_OI; | |
2915 | ||
2916 | if (reg_flags & PFM_REGFL_OVFL_NOTIFY) { | |
2917 | flags |= PFM_REGFL_OVFL_NOTIFY; | |
2918 | } | |
2919 | ||
2920 | if (reg_flags & PFM_REGFL_RANDOM) flags |= PFM_REGFL_RANDOM; | |
2921 | ||
2922 | /* verify validity of smpl_pmds */ | |
2923 | if ((smpl_pmds & impl_pmds) != smpl_pmds) { | |
2924 | DPRINT(("invalid smpl_pmds 0x%lx for pmc%u\n", smpl_pmds, cnum)); | |
2925 | goto error; | |
2926 | } | |
2927 | ||
2928 | /* verify validity of reset_pmds */ | |
2929 | if ((reset_pmds & impl_pmds) != reset_pmds) { | |
2930 | DPRINT(("invalid reset_pmds 0x%lx for pmc%u\n", reset_pmds, cnum)); | |
2931 | goto error; | |
2932 | } | |
2933 | } else { | |
2934 | if (reg_flags & (PFM_REGFL_OVFL_NOTIFY|PFM_REGFL_RANDOM)) { | |
2935 | DPRINT(("cannot set ovfl_notify or random on pmc%u\n", cnum)); | |
2936 | goto error; | |
2937 | } | |
2938 | /* eventid on non-counting monitors are ignored */ | |
2939 | } | |
2940 | ||
2941 | /* | |
2942 | * execute write checker, if any | |
2943 | */ | |
2944 | if (likely(expert_mode == 0 && wr_func)) { | |
2945 | ret = (*wr_func)(task, ctx, cnum, &value, regs); | |
2946 | if (ret) goto error; | |
2947 | ret = -EINVAL; | |
2948 | } | |
2949 | ||
2950 | /* | |
2951 | * no error on this register | |
2952 | */ | |
2953 | PFM_REG_RETFLAG_SET(req->reg_flags, 0); | |
2954 | ||
2955 | /* | |
2956 | * Now we commit the changes to the software state | |
2957 | */ | |
2958 | ||
2959 | /* | |
2960 | * update overflow information | |
2961 | */ | |
2962 | if (is_counting) { | |
2963 | /* | |
2964 | * full flag update each time a register is programmed | |
2965 | */ | |
2966 | ctx->ctx_pmds[cnum].flags = flags; | |
2967 | ||
2968 | ctx->ctx_pmds[cnum].reset_pmds[0] = reset_pmds; | |
2969 | ctx->ctx_pmds[cnum].smpl_pmds[0] = smpl_pmds; | |
2970 | ctx->ctx_pmds[cnum].eventid = req->reg_smpl_eventid; | |
2971 | ||
2972 | /* | |
2973 | * Mark all PMDS to be accessed as used. | |
2974 | * | |
2975 | * We do not keep track of PMC because we have to | |
2976 | * systematically restore ALL of them. | |
2977 | * | |
2978 | * We do not update the used_monitors mask, because | |
2979 | * if we have not programmed them, then will be in | |
2980 | * a quiescent state, therefore we will not need to | |
2981 | * mask/restore then when context is MASKED. | |
2982 | */ | |
2983 | CTX_USED_PMD(ctx, reset_pmds); | |
2984 | CTX_USED_PMD(ctx, smpl_pmds); | |
2985 | /* | |
2986 | * make sure we do not try to reset on | |
2987 | * restart because we have established new values | |
2988 | */ | |
2989 | if (state == PFM_CTX_MASKED) ctx->ctx_ovfl_regs[0] &= ~1UL << cnum; | |
2990 | } | |
2991 | /* | |
2992 | * Needed in case the user does not initialize the equivalent | |
2993 | * PMD. Clearing is done indirectly via pfm_reset_pmu_state() so there is no | |
2994 | * possible leak here. | |
2995 | */ | |
2996 | CTX_USED_PMD(ctx, pmu_conf->pmc_desc[cnum].dep_pmd[0]); | |
2997 | ||
2998 | /* | |
2999 | * keep track of the monitor PMC that we are using. | |
3000 | * we save the value of the pmc in ctx_pmcs[] and if | |
3001 | * the monitoring is not stopped for the context we also | |
3002 | * place it in the saved state area so that it will be | |
3003 | * picked up later by the context switch code. | |
3004 | * | |
3005 | * The value in ctx_pmcs[] can only be changed in pfm_write_pmcs(). | |
3006 | * | |
35589a8f | 3007 | * The value in th_pmcs[] may be modified on overflow, i.e., when |
1da177e4 LT |
3008 | * monitoring needs to be stopped. |
3009 | */ | |
3010 | if (is_monitor) CTX_USED_MONITOR(ctx, 1UL << cnum); | |
3011 | ||
3012 | /* | |
3013 | * update context state | |
3014 | */ | |
3015 | ctx->ctx_pmcs[cnum] = value; | |
3016 | ||
3017 | if (is_loaded) { | |
3018 | /* | |
3019 | * write thread state | |
3020 | */ | |
35589a8f | 3021 | if (is_system == 0) ctx->th_pmcs[cnum] = value; |
1da177e4 LT |
3022 | |
3023 | /* | |
3024 | * write hardware register if we can | |
3025 | */ | |
3026 | if (can_access_pmu) { | |
3027 | ia64_set_pmc(cnum, value); | |
3028 | } | |
3029 | #ifdef CONFIG_SMP | |
3030 | else { | |
3031 | /* | |
3032 | * per-task SMP only here | |
3033 | * | |
3034 | * we are guaranteed that the task is not running on the other CPU, | |
3035 | * we indicate that this PMD will need to be reloaded if the task | |
3036 | * is rescheduled on the CPU it ran last on. | |
3037 | */ | |
3038 | ctx->ctx_reload_pmcs[0] |= 1UL << cnum; | |
3039 | } | |
3040 | #endif | |
3041 | } | |
3042 | ||
3043 | DPRINT(("pmc[%u]=0x%lx ld=%d apmu=%d flags=0x%x all_pmcs=0x%lx used_pmds=0x%lx eventid=%ld smpl_pmds=0x%lx reset_pmds=0x%lx reloads_pmcs=0x%lx used_monitors=0x%lx ovfl_regs=0x%lx\n", | |
3044 | cnum, | |
3045 | value, | |
3046 | is_loaded, | |
3047 | can_access_pmu, | |
3048 | flags, | |
3049 | ctx->ctx_all_pmcs[0], | |
3050 | ctx->ctx_used_pmds[0], | |
3051 | ctx->ctx_pmds[cnum].eventid, | |
3052 | smpl_pmds, | |
3053 | reset_pmds, | |
3054 | ctx->ctx_reload_pmcs[0], | |
3055 | ctx->ctx_used_monitors[0], | |
3056 | ctx->ctx_ovfl_regs[0])); | |
3057 | } | |
3058 | ||
3059 | /* | |
3060 | * make sure the changes are visible | |
3061 | */ | |
3062 | if (can_access_pmu) ia64_srlz_d(); | |
3063 | ||
3064 | return 0; | |
3065 | error: | |
3066 | PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); | |
3067 | return ret; | |
3068 | } | |
3069 | ||
3070 | static int | |
3071 | pfm_write_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3072 | { | |
1da177e4 LT |
3073 | struct task_struct *task; |
3074 | pfarg_reg_t *req = (pfarg_reg_t *)arg; | |
3075 | unsigned long value, hw_value, ovfl_mask; | |
3076 | unsigned int cnum; | |
3077 | int i, can_access_pmu = 0, state; | |
3078 | int is_counting, is_loaded, is_system, expert_mode; | |
3079 | int ret = -EINVAL; | |
3080 | pfm_reg_check_t wr_func; | |
3081 | ||
3082 | ||
3083 | state = ctx->ctx_state; | |
3084 | is_loaded = state == PFM_CTX_LOADED ? 1 : 0; | |
3085 | is_system = ctx->ctx_fl_system; | |
3086 | ovfl_mask = pmu_conf->ovfl_val; | |
3087 | task = ctx->ctx_task; | |
3088 | ||
3089 | if (unlikely(state == PFM_CTX_ZOMBIE)) return -EINVAL; | |
3090 | ||
3091 | /* | |
3092 | * on both UP and SMP, we can only write to the PMC when the task is | |
3093 | * the owner of the local PMU. | |
3094 | */ | |
3095 | if (likely(is_loaded)) { | |
1da177e4 LT |
3096 | /* |
3097 | * In system wide and when the context is loaded, access can only happen | |
3098 | * when the caller is running on the CPU being monitored by the session. | |
3099 | * It does not have to be the owner (ctx_task) of the context per se. | |
3100 | */ | |
3101 | if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) { | |
3102 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
3103 | return -EBUSY; | |
3104 | } | |
3105 | can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; | |
3106 | } | |
3107 | expert_mode = pfm_sysctl.expert_mode; | |
3108 | ||
3109 | for (i = 0; i < count; i++, req++) { | |
3110 | ||
3111 | cnum = req->reg_num; | |
3112 | value = req->reg_value; | |
3113 | ||
3114 | if (!PMD_IS_IMPL(cnum)) { | |
3115 | DPRINT(("pmd[%u] is unimplemented or invalid\n", cnum)); | |
3116 | goto abort_mission; | |
3117 | } | |
3118 | is_counting = PMD_IS_COUNTING(cnum); | |
3119 | wr_func = pmu_conf->pmd_desc[cnum].write_check; | |
3120 | ||
3121 | /* | |
3122 | * execute write checker, if any | |
3123 | */ | |
3124 | if (unlikely(expert_mode == 0 && wr_func)) { | |
3125 | unsigned long v = value; | |
3126 | ||
3127 | ret = (*wr_func)(task, ctx, cnum, &v, regs); | |
3128 | if (ret) goto abort_mission; | |
3129 | ||
3130 | value = v; | |
3131 | ret = -EINVAL; | |
3132 | } | |
3133 | ||
3134 | /* | |
3135 | * no error on this register | |
3136 | */ | |
3137 | PFM_REG_RETFLAG_SET(req->reg_flags, 0); | |
3138 | ||
3139 | /* | |
3140 | * now commit changes to software state | |
3141 | */ | |
3142 | hw_value = value; | |
3143 | ||
3144 | /* | |
3145 | * update virtualized (64bits) counter | |
3146 | */ | |
3147 | if (is_counting) { | |
3148 | /* | |
3149 | * write context state | |
3150 | */ | |
3151 | ctx->ctx_pmds[cnum].lval = value; | |
3152 | ||
3153 | /* | |
3154 | * when context is load we use the split value | |
3155 | */ | |
3156 | if (is_loaded) { | |
3157 | hw_value = value & ovfl_mask; | |
3158 | value = value & ~ovfl_mask; | |
3159 | } | |
3160 | } | |
3161 | /* | |
3162 | * update reset values (not just for counters) | |
3163 | */ | |
3164 | ctx->ctx_pmds[cnum].long_reset = req->reg_long_reset; | |
3165 | ctx->ctx_pmds[cnum].short_reset = req->reg_short_reset; | |
3166 | ||
3167 | /* | |
3168 | * update randomization parameters (not just for counters) | |
3169 | */ | |
3170 | ctx->ctx_pmds[cnum].seed = req->reg_random_seed; | |
3171 | ctx->ctx_pmds[cnum].mask = req->reg_random_mask; | |
3172 | ||
3173 | /* | |
3174 | * update context value | |
3175 | */ | |
3176 | ctx->ctx_pmds[cnum].val = value; | |
3177 | ||
3178 | /* | |
3179 | * Keep track of what we use | |
3180 | * | |
3181 | * We do not keep track of PMC because we have to | |
3182 | * systematically restore ALL of them. | |
3183 | */ | |
3184 | CTX_USED_PMD(ctx, PMD_PMD_DEP(cnum)); | |
3185 | ||
3186 | /* | |
3187 | * mark this PMD register used as well | |
3188 | */ | |
3189 | CTX_USED_PMD(ctx, RDEP(cnum)); | |
3190 | ||
3191 | /* | |
3192 | * make sure we do not try to reset on | |
3193 | * restart because we have established new values | |
3194 | */ | |
3195 | if (is_counting && state == PFM_CTX_MASKED) { | |
3196 | ctx->ctx_ovfl_regs[0] &= ~1UL << cnum; | |
3197 | } | |
3198 | ||
3199 | if (is_loaded) { | |
3200 | /* | |
3201 | * write thread state | |
3202 | */ | |
35589a8f | 3203 | if (is_system == 0) ctx->th_pmds[cnum] = hw_value; |
1da177e4 LT |
3204 | |
3205 | /* | |
3206 | * write hardware register if we can | |
3207 | */ | |
3208 | if (can_access_pmu) { | |
3209 | ia64_set_pmd(cnum, hw_value); | |
3210 | } else { | |
3211 | #ifdef CONFIG_SMP | |
3212 | /* | |
3213 | * we are guaranteed that the task is not running on the other CPU, | |
3214 | * we indicate that this PMD will need to be reloaded if the task | |
3215 | * is rescheduled on the CPU it ran last on. | |
3216 | */ | |
3217 | ctx->ctx_reload_pmds[0] |= 1UL << cnum; | |
3218 | #endif | |
3219 | } | |
3220 | } | |
3221 | ||
3222 | DPRINT(("pmd[%u]=0x%lx ld=%d apmu=%d, hw_value=0x%lx ctx_pmd=0x%lx short_reset=0x%lx " | |
3223 | "long_reset=0x%lx notify=%c seed=0x%lx mask=0x%lx used_pmds=0x%lx reset_pmds=0x%lx reload_pmds=0x%lx all_pmds=0x%lx ovfl_regs=0x%lx\n", | |
3224 | cnum, | |
3225 | value, | |
3226 | is_loaded, | |
3227 | can_access_pmu, | |
3228 | hw_value, | |
3229 | ctx->ctx_pmds[cnum].val, | |
3230 | ctx->ctx_pmds[cnum].short_reset, | |
3231 | ctx->ctx_pmds[cnum].long_reset, | |
3232 | PMC_OVFL_NOTIFY(ctx, cnum) ? 'Y':'N', | |
3233 | ctx->ctx_pmds[cnum].seed, | |
3234 | ctx->ctx_pmds[cnum].mask, | |
3235 | ctx->ctx_used_pmds[0], | |
3236 | ctx->ctx_pmds[cnum].reset_pmds[0], | |
3237 | ctx->ctx_reload_pmds[0], | |
3238 | ctx->ctx_all_pmds[0], | |
3239 | ctx->ctx_ovfl_regs[0])); | |
3240 | } | |
3241 | ||
3242 | /* | |
3243 | * make changes visible | |
3244 | */ | |
3245 | if (can_access_pmu) ia64_srlz_d(); | |
3246 | ||
3247 | return 0; | |
3248 | ||
3249 | abort_mission: | |
3250 | /* | |
3251 | * for now, we have only one possibility for error | |
3252 | */ | |
3253 | PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); | |
3254 | return ret; | |
3255 | } | |
3256 | ||
3257 | /* | |
3258 | * By the way of PROTECT_CONTEXT(), interrupts are masked while we are in this function. | |
3259 | * Therefore we know, we do not have to worry about the PMU overflow interrupt. If an | |
3260 | * interrupt is delivered during the call, it will be kept pending until we leave, making | |
3261 | * it appears as if it had been generated at the UNPROTECT_CONTEXT(). At least we are | |
3262 | * guaranteed to return consistent data to the user, it may simply be old. It is not | |
3263 | * trivial to treat the overflow while inside the call because you may end up in | |
3264 | * some module sampling buffer code causing deadlocks. | |
3265 | */ | |
3266 | static int | |
3267 | pfm_read_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3268 | { | |
1da177e4 LT |
3269 | struct task_struct *task; |
3270 | unsigned long val = 0UL, lval, ovfl_mask, sval; | |
3271 | pfarg_reg_t *req = (pfarg_reg_t *)arg; | |
3272 | unsigned int cnum, reg_flags = 0; | |
3273 | int i, can_access_pmu = 0, state; | |
3274 | int is_loaded, is_system, is_counting, expert_mode; | |
3275 | int ret = -EINVAL; | |
3276 | pfm_reg_check_t rd_func; | |
3277 | ||
3278 | /* | |
3279 | * access is possible when loaded only for | |
3280 | * self-monitoring tasks or in UP mode | |
3281 | */ | |
3282 | ||
3283 | state = ctx->ctx_state; | |
3284 | is_loaded = state == PFM_CTX_LOADED ? 1 : 0; | |
3285 | is_system = ctx->ctx_fl_system; | |
3286 | ovfl_mask = pmu_conf->ovfl_val; | |
3287 | task = ctx->ctx_task; | |
3288 | ||
3289 | if (state == PFM_CTX_ZOMBIE) return -EINVAL; | |
3290 | ||
3291 | if (likely(is_loaded)) { | |
1da177e4 LT |
3292 | /* |
3293 | * In system wide and when the context is loaded, access can only happen | |
3294 | * when the caller is running on the CPU being monitored by the session. | |
3295 | * It does not have to be the owner (ctx_task) of the context per se. | |
3296 | */ | |
3297 | if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) { | |
3298 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
3299 | return -EBUSY; | |
3300 | } | |
3301 | /* | |
3302 | * this can be true when not self-monitoring only in UP | |
3303 | */ | |
3304 | can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; | |
3305 | ||
3306 | if (can_access_pmu) ia64_srlz_d(); | |
3307 | } | |
3308 | expert_mode = pfm_sysctl.expert_mode; | |
3309 | ||
3310 | DPRINT(("ld=%d apmu=%d ctx_state=%d\n", | |
3311 | is_loaded, | |
3312 | can_access_pmu, | |
3313 | state)); | |
3314 | ||
3315 | /* | |
3316 | * on both UP and SMP, we can only read the PMD from the hardware register when | |
3317 | * the task is the owner of the local PMU. | |
3318 | */ | |
3319 | ||
3320 | for (i = 0; i < count; i++, req++) { | |
3321 | ||
3322 | cnum = req->reg_num; | |
3323 | reg_flags = req->reg_flags; | |
3324 | ||
3325 | if (unlikely(!PMD_IS_IMPL(cnum))) goto error; | |
3326 | /* | |
3327 | * we can only read the register that we use. That includes | |
72fdbdce | 3328 | * the one we explicitly initialize AND the one we want included |
1da177e4 LT |
3329 | * in the sampling buffer (smpl_regs). |
3330 | * | |
3331 | * Having this restriction allows optimization in the ctxsw routine | |
3332 | * without compromising security (leaks) | |
3333 | */ | |
3334 | if (unlikely(!CTX_IS_USED_PMD(ctx, cnum))) goto error; | |
3335 | ||
3336 | sval = ctx->ctx_pmds[cnum].val; | |
3337 | lval = ctx->ctx_pmds[cnum].lval; | |
3338 | is_counting = PMD_IS_COUNTING(cnum); | |
3339 | ||
3340 | /* | |
3341 | * If the task is not the current one, then we check if the | |
3342 | * PMU state is still in the local live register due to lazy ctxsw. | |
3343 | * If true, then we read directly from the registers. | |
3344 | */ | |
3345 | if (can_access_pmu){ | |
3346 | val = ia64_get_pmd(cnum); | |
3347 | } else { | |
3348 | /* | |
3349 | * context has been saved | |
3350 | * if context is zombie, then task does not exist anymore. | |
3351 | * In this case, we use the full value saved in the context (pfm_flush_regs()). | |
3352 | */ | |
35589a8f | 3353 | val = is_loaded ? ctx->th_pmds[cnum] : 0UL; |
1da177e4 LT |
3354 | } |
3355 | rd_func = pmu_conf->pmd_desc[cnum].read_check; | |
3356 | ||
3357 | if (is_counting) { | |
3358 | /* | |
3359 | * XXX: need to check for overflow when loaded | |
3360 | */ | |
3361 | val &= ovfl_mask; | |
3362 | val += sval; | |
3363 | } | |
3364 | ||
3365 | /* | |
3366 | * execute read checker, if any | |
3367 | */ | |
3368 | if (unlikely(expert_mode == 0 && rd_func)) { | |
3369 | unsigned long v = val; | |
3370 | ret = (*rd_func)(ctx->ctx_task, ctx, cnum, &v, regs); | |
3371 | if (ret) goto error; | |
3372 | val = v; | |
3373 | ret = -EINVAL; | |
3374 | } | |
3375 | ||
3376 | PFM_REG_RETFLAG_SET(reg_flags, 0); | |
3377 | ||
3378 | DPRINT(("pmd[%u]=0x%lx\n", cnum, val)); | |
3379 | ||
3380 | /* | |
3381 | * update register return value, abort all if problem during copy. | |
3382 | * we only modify the reg_flags field. no check mode is fine because | |
3383 | * access has been verified upfront in sys_perfmonctl(). | |
3384 | */ | |
3385 | req->reg_value = val; | |
3386 | req->reg_flags = reg_flags; | |
3387 | req->reg_last_reset_val = lval; | |
3388 | } | |
3389 | ||
3390 | return 0; | |
3391 | ||
3392 | error: | |
3393 | PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); | |
3394 | return ret; | |
3395 | } | |
3396 | ||
3397 | int | |
3398 | pfm_mod_write_pmcs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) | |
3399 | { | |
3400 | pfm_context_t *ctx; | |
3401 | ||
3402 | if (req == NULL) return -EINVAL; | |
3403 | ||
3404 | ctx = GET_PMU_CTX(); | |
3405 | ||
3406 | if (ctx == NULL) return -EINVAL; | |
3407 | ||
3408 | /* | |
3409 | * for now limit to current task, which is enough when calling | |
3410 | * from overflow handler | |
3411 | */ | |
3412 | if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; | |
3413 | ||
3414 | return pfm_write_pmcs(ctx, req, nreq, regs); | |
3415 | } | |
3416 | EXPORT_SYMBOL(pfm_mod_write_pmcs); | |
3417 | ||
3418 | int | |
3419 | pfm_mod_read_pmds(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) | |
3420 | { | |
3421 | pfm_context_t *ctx; | |
3422 | ||
3423 | if (req == NULL) return -EINVAL; | |
3424 | ||
3425 | ctx = GET_PMU_CTX(); | |
3426 | ||
3427 | if (ctx == NULL) return -EINVAL; | |
3428 | ||
3429 | /* | |
3430 | * for now limit to current task, which is enough when calling | |
3431 | * from overflow handler | |
3432 | */ | |
3433 | if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; | |
3434 | ||
3435 | return pfm_read_pmds(ctx, req, nreq, regs); | |
3436 | } | |
3437 | EXPORT_SYMBOL(pfm_mod_read_pmds); | |
3438 | ||
3439 | /* | |
3440 | * Only call this function when a process it trying to | |
3441 | * write the debug registers (reading is always allowed) | |
3442 | */ | |
3443 | int | |
3444 | pfm_use_debug_registers(struct task_struct *task) | |
3445 | { | |
3446 | pfm_context_t *ctx = task->thread.pfm_context; | |
3447 | unsigned long flags; | |
3448 | int ret = 0; | |
3449 | ||
3450 | if (pmu_conf->use_rr_dbregs == 0) return 0; | |
3451 | ||
19c5870c | 3452 | DPRINT(("called for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
3453 | |
3454 | /* | |
3455 | * do it only once | |
3456 | */ | |
3457 | if (task->thread.flags & IA64_THREAD_DBG_VALID) return 0; | |
3458 | ||
3459 | /* | |
3460 | * Even on SMP, we do not need to use an atomic here because | |
3461 | * the only way in is via ptrace() and this is possible only when the | |
3462 | * process is stopped. Even in the case where the ctxsw out is not totally | |
3463 | * completed by the time we come here, there is no way the 'stopped' process | |
3464 | * could be in the middle of fiddling with the pfm_write_ibr_dbr() routine. | |
3465 | * So this is always safe. | |
3466 | */ | |
3467 | if (ctx && ctx->ctx_fl_using_dbreg == 1) return -1; | |
3468 | ||
3469 | LOCK_PFS(flags); | |
3470 | ||
3471 | /* | |
3472 | * We cannot allow setting breakpoints when system wide monitoring | |
3473 | * sessions are using the debug registers. | |
3474 | */ | |
3475 | if (pfm_sessions.pfs_sys_use_dbregs> 0) | |
3476 | ret = -1; | |
3477 | else | |
3478 | pfm_sessions.pfs_ptrace_use_dbregs++; | |
3479 | ||
3480 | DPRINT(("ptrace_use_dbregs=%u sys_use_dbregs=%u by [%d] ret = %d\n", | |
3481 | pfm_sessions.pfs_ptrace_use_dbregs, | |
3482 | pfm_sessions.pfs_sys_use_dbregs, | |
19c5870c | 3483 | task_pid_nr(task), ret)); |
1da177e4 LT |
3484 | |
3485 | UNLOCK_PFS(flags); | |
3486 | ||
3487 | return ret; | |
3488 | } | |
3489 | ||
3490 | /* | |
3491 | * This function is called for every task that exits with the | |
3492 | * IA64_THREAD_DBG_VALID set. This indicates a task which was | |
3493 | * able to use the debug registers for debugging purposes via | |
3494 | * ptrace(). Therefore we know it was not using them for | |
af901ca1 | 3495 | * performance monitoring, so we only decrement the number |
1da177e4 LT |
3496 | * of "ptraced" debug register users to keep the count up to date |
3497 | */ | |
3498 | int | |
3499 | pfm_release_debug_registers(struct task_struct *task) | |
3500 | { | |
3501 | unsigned long flags; | |
3502 | int ret; | |
3503 | ||
3504 | if (pmu_conf->use_rr_dbregs == 0) return 0; | |
3505 | ||
3506 | LOCK_PFS(flags); | |
3507 | if (pfm_sessions.pfs_ptrace_use_dbregs == 0) { | |
19c5870c | 3508 | printk(KERN_ERR "perfmon: invalid release for [%d] ptrace_use_dbregs=0\n", task_pid_nr(task)); |
1da177e4 LT |
3509 | ret = -1; |
3510 | } else { | |
3511 | pfm_sessions.pfs_ptrace_use_dbregs--; | |
3512 | ret = 0; | |
3513 | } | |
3514 | UNLOCK_PFS(flags); | |
3515 | ||
3516 | return ret; | |
3517 | } | |
3518 | ||
3519 | static int | |
3520 | pfm_restart(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3521 | { | |
3522 | struct task_struct *task; | |
3523 | pfm_buffer_fmt_t *fmt; | |
3524 | pfm_ovfl_ctrl_t rst_ctrl; | |
3525 | int state, is_system; | |
3526 | int ret = 0; | |
3527 | ||
3528 | state = ctx->ctx_state; | |
3529 | fmt = ctx->ctx_buf_fmt; | |
3530 | is_system = ctx->ctx_fl_system; | |
3531 | task = PFM_CTX_TASK(ctx); | |
3532 | ||
3533 | switch(state) { | |
3534 | case PFM_CTX_MASKED: | |
3535 | break; | |
3536 | case PFM_CTX_LOADED: | |
3537 | if (CTX_HAS_SMPL(ctx) && fmt->fmt_restart_active) break; | |
3538 | /* fall through */ | |
3539 | case PFM_CTX_UNLOADED: | |
3540 | case PFM_CTX_ZOMBIE: | |
3541 | DPRINT(("invalid state=%d\n", state)); | |
3542 | return -EBUSY; | |
3543 | default: | |
3544 | DPRINT(("state=%d, cannot operate (no active_restart handler)\n", state)); | |
3545 | return -EINVAL; | |
3546 | } | |
3547 | ||
3548 | /* | |
3549 | * In system wide and when the context is loaded, access can only happen | |
3550 | * when the caller is running on the CPU being monitored by the session. | |
3551 | * It does not have to be the owner (ctx_task) of the context per se. | |
3552 | */ | |
3553 | if (is_system && ctx->ctx_cpu != smp_processor_id()) { | |
3554 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
3555 | return -EBUSY; | |
3556 | } | |
3557 | ||
3558 | /* sanity check */ | |
3559 | if (unlikely(task == NULL)) { | |
19c5870c | 3560 | printk(KERN_ERR "perfmon: [%d] pfm_restart no task\n", task_pid_nr(current)); |
1da177e4 LT |
3561 | return -EINVAL; |
3562 | } | |
3563 | ||
3564 | if (task == current || is_system) { | |
3565 | ||
3566 | fmt = ctx->ctx_buf_fmt; | |
3567 | ||
3568 | DPRINT(("restarting self %d ovfl=0x%lx\n", | |
19c5870c | 3569 | task_pid_nr(task), |
1da177e4 LT |
3570 | ctx->ctx_ovfl_regs[0])); |
3571 | ||
3572 | if (CTX_HAS_SMPL(ctx)) { | |
3573 | ||
3574 | prefetch(ctx->ctx_smpl_hdr); | |
3575 | ||
3576 | rst_ctrl.bits.mask_monitoring = 0; | |
3577 | rst_ctrl.bits.reset_ovfl_pmds = 0; | |
3578 | ||
3579 | if (state == PFM_CTX_LOADED) | |
3580 | ret = pfm_buf_fmt_restart_active(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs); | |
3581 | else | |
3582 | ret = pfm_buf_fmt_restart(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs); | |
3583 | } else { | |
3584 | rst_ctrl.bits.mask_monitoring = 0; | |
3585 | rst_ctrl.bits.reset_ovfl_pmds = 1; | |
3586 | } | |
3587 | ||
3588 | if (ret == 0) { | |
3589 | if (rst_ctrl.bits.reset_ovfl_pmds) | |
3590 | pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET); | |
3591 | ||
3592 | if (rst_ctrl.bits.mask_monitoring == 0) { | |
19c5870c | 3593 | DPRINT(("resuming monitoring for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
3594 | |
3595 | if (state == PFM_CTX_MASKED) pfm_restore_monitoring(task); | |
3596 | } else { | |
19c5870c | 3597 | DPRINT(("keeping monitoring stopped for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
3598 | |
3599 | // cannot use pfm_stop_monitoring(task, regs); | |
3600 | } | |
3601 | } | |
3602 | /* | |
3603 | * clear overflowed PMD mask to remove any stale information | |
3604 | */ | |
3605 | ctx->ctx_ovfl_regs[0] = 0UL; | |
3606 | ||
3607 | /* | |
3608 | * back to LOADED state | |
3609 | */ | |
3610 | ctx->ctx_state = PFM_CTX_LOADED; | |
3611 | ||
3612 | /* | |
3613 | * XXX: not really useful for self monitoring | |
3614 | */ | |
3615 | ctx->ctx_fl_can_restart = 0; | |
3616 | ||
3617 | return 0; | |
3618 | } | |
3619 | ||
3620 | /* | |
3621 | * restart another task | |
3622 | */ | |
3623 | ||
3624 | /* | |
3625 | * When PFM_CTX_MASKED, we cannot issue a restart before the previous | |
3626 | * one is seen by the task. | |
3627 | */ | |
3628 | if (state == PFM_CTX_MASKED) { | |
3629 | if (ctx->ctx_fl_can_restart == 0) return -EINVAL; | |
3630 | /* | |
3631 | * will prevent subsequent restart before this one is | |
3632 | * seen by other task | |
3633 | */ | |
3634 | ctx->ctx_fl_can_restart = 0; | |
3635 | } | |
3636 | ||
3637 | /* | |
3638 | * if blocking, then post the semaphore is PFM_CTX_MASKED, i.e. | |
3639 | * the task is blocked or on its way to block. That's the normal | |
3640 | * restart path. If the monitoring is not masked, then the task | |
3641 | * can be actively monitoring and we cannot directly intervene. | |
3642 | * Therefore we use the trap mechanism to catch the task and | |
3643 | * force it to reset the buffer/reset PMDs. | |
3644 | * | |
3645 | * if non-blocking, then we ensure that the task will go into | |
3646 | * pfm_handle_work() before returning to user mode. | |
3647 | * | |
72fdbdce | 3648 | * We cannot explicitly reset another task, it MUST always |
1da177e4 LT |
3649 | * be done by the task itself. This works for system wide because |
3650 | * the tool that is controlling the session is logically doing | |
3651 | * "self-monitoring". | |
3652 | */ | |
3653 | if (CTX_OVFL_NOBLOCK(ctx) == 0 && state == PFM_CTX_MASKED) { | |
04157e4c | 3654 | DPRINT(("unblocking [%d]\n", task_pid_nr(task))); |
60f1c444 | 3655 | complete(&ctx->ctx_restart_done); |
1da177e4 | 3656 | } else { |
19c5870c | 3657 | DPRINT(("[%d] armed exit trap\n", task_pid_nr(task))); |
1da177e4 LT |
3658 | |
3659 | ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_RESET; | |
3660 | ||
3661 | PFM_SET_WORK_PENDING(task, 1); | |
3662 | ||
f14488cc | 3663 | set_notify_resume(task); |
1da177e4 LT |
3664 | |
3665 | /* | |
3666 | * XXX: send reschedule if task runs on another CPU | |
3667 | */ | |
3668 | } | |
3669 | return 0; | |
3670 | } | |
3671 | ||
3672 | static int | |
3673 | pfm_debug(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3674 | { | |
3675 | unsigned int m = *(unsigned int *)arg; | |
3676 | ||
3677 | pfm_sysctl.debug = m == 0 ? 0 : 1; | |
3678 | ||
1da177e4 LT |
3679 | printk(KERN_INFO "perfmon debugging %s (timing reset)\n", pfm_sysctl.debug ? "on" : "off"); |
3680 | ||
3681 | if (m == 0) { | |
3682 | memset(pfm_stats, 0, sizeof(pfm_stats)); | |
3683 | for(m=0; m < NR_CPUS; m++) pfm_stats[m].pfm_ovfl_intr_cycles_min = ~0UL; | |
3684 | } | |
3685 | return 0; | |
3686 | } | |
3687 | ||
3688 | /* | |
3689 | * arg can be NULL and count can be zero for this function | |
3690 | */ | |
3691 | static int | |
3692 | pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3693 | { | |
3694 | struct thread_struct *thread = NULL; | |
3695 | struct task_struct *task; | |
3696 | pfarg_dbreg_t *req = (pfarg_dbreg_t *)arg; | |
3697 | unsigned long flags; | |
3698 | dbreg_t dbreg; | |
3699 | unsigned int rnum; | |
3700 | int first_time; | |
3701 | int ret = 0, state; | |
3702 | int i, can_access_pmu = 0; | |
3703 | int is_system, is_loaded; | |
3704 | ||
3705 | if (pmu_conf->use_rr_dbregs == 0) return -EINVAL; | |
3706 | ||
3707 | state = ctx->ctx_state; | |
3708 | is_loaded = state == PFM_CTX_LOADED ? 1 : 0; | |
3709 | is_system = ctx->ctx_fl_system; | |
3710 | task = ctx->ctx_task; | |
3711 | ||
3712 | if (state == PFM_CTX_ZOMBIE) return -EINVAL; | |
3713 | ||
3714 | /* | |
3715 | * on both UP and SMP, we can only write to the PMC when the task is | |
3716 | * the owner of the local PMU. | |
3717 | */ | |
3718 | if (is_loaded) { | |
3719 | thread = &task->thread; | |
3720 | /* | |
3721 | * In system wide and when the context is loaded, access can only happen | |
3722 | * when the caller is running on the CPU being monitored by the session. | |
3723 | * It does not have to be the owner (ctx_task) of the context per se. | |
3724 | */ | |
3725 | if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) { | |
3726 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
3727 | return -EBUSY; | |
3728 | } | |
3729 | can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; | |
3730 | } | |
3731 | ||
3732 | /* | |
3733 | * we do not need to check for ipsr.db because we do clear ibr.x, dbr.r, and dbr.w | |
3734 | * ensuring that no real breakpoint can be installed via this call. | |
3735 | * | |
3736 | * IMPORTANT: regs can be NULL in this function | |
3737 | */ | |
3738 | ||
3739 | first_time = ctx->ctx_fl_using_dbreg == 0; | |
3740 | ||
3741 | /* | |
3742 | * don't bother if we are loaded and task is being debugged | |
3743 | */ | |
3744 | if (is_loaded && (thread->flags & IA64_THREAD_DBG_VALID) != 0) { | |
19c5870c | 3745 | DPRINT(("debug registers already in use for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
3746 | return -EBUSY; |
3747 | } | |
3748 | ||
3749 | /* | |
3750 | * check for debug registers in system wide mode | |
3751 | * | |
3752 | * If though a check is done in pfm_context_load(), | |
3753 | * we must repeat it here, in case the registers are | |
3754 | * written after the context is loaded | |
3755 | */ | |
3756 | if (is_loaded) { | |
3757 | LOCK_PFS(flags); | |
3758 | ||
3759 | if (first_time && is_system) { | |
3760 | if (pfm_sessions.pfs_ptrace_use_dbregs) | |
3761 | ret = -EBUSY; | |
3762 | else | |
3763 | pfm_sessions.pfs_sys_use_dbregs++; | |
3764 | } | |
3765 | UNLOCK_PFS(flags); | |
3766 | } | |
3767 | ||
3768 | if (ret != 0) return ret; | |
3769 | ||
3770 | /* | |
3771 | * mark ourself as user of the debug registers for | |
3772 | * perfmon purposes. | |
3773 | */ | |
3774 | ctx->ctx_fl_using_dbreg = 1; | |
3775 | ||
3776 | /* | |
3777 | * clear hardware registers to make sure we don't | |
3778 | * pick up stale state. | |
3779 | * | |
3780 | * for a system wide session, we do not use | |
3781 | * thread.dbr, thread.ibr because this process | |
3782 | * never leaves the current CPU and the state | |
3783 | * is shared by all processes running on it | |
3784 | */ | |
3785 | if (first_time && can_access_pmu) { | |
19c5870c | 3786 | DPRINT(("[%d] clearing ibrs, dbrs\n", task_pid_nr(task))); |
1da177e4 LT |
3787 | for (i=0; i < pmu_conf->num_ibrs; i++) { |
3788 | ia64_set_ibr(i, 0UL); | |
3789 | ia64_dv_serialize_instruction(); | |
3790 | } | |
3791 | ia64_srlz_i(); | |
3792 | for (i=0; i < pmu_conf->num_dbrs; i++) { | |
3793 | ia64_set_dbr(i, 0UL); | |
3794 | ia64_dv_serialize_data(); | |
3795 | } | |
3796 | ia64_srlz_d(); | |
3797 | } | |
3798 | ||
3799 | /* | |
3800 | * Now install the values into the registers | |
3801 | */ | |
3802 | for (i = 0; i < count; i++, req++) { | |
3803 | ||
3804 | rnum = req->dbreg_num; | |
3805 | dbreg.val = req->dbreg_value; | |
3806 | ||
3807 | ret = -EINVAL; | |
3808 | ||
3809 | if ((mode == PFM_CODE_RR && rnum >= PFM_NUM_IBRS) || ((mode == PFM_DATA_RR) && rnum >= PFM_NUM_DBRS)) { | |
3810 | DPRINT(("invalid register %u val=0x%lx mode=%d i=%d count=%d\n", | |
3811 | rnum, dbreg.val, mode, i, count)); | |
3812 | ||
3813 | goto abort_mission; | |
3814 | } | |
3815 | ||
3816 | /* | |
3817 | * make sure we do not install enabled breakpoint | |
3818 | */ | |
3819 | if (rnum & 0x1) { | |
3820 | if (mode == PFM_CODE_RR) | |
3821 | dbreg.ibr.ibr_x = 0; | |
3822 | else | |
3823 | dbreg.dbr.dbr_r = dbreg.dbr.dbr_w = 0; | |
3824 | } | |
3825 | ||
3826 | PFM_REG_RETFLAG_SET(req->dbreg_flags, 0); | |
3827 | ||
3828 | /* | |
3829 | * Debug registers, just like PMC, can only be modified | |
3830 | * by a kernel call. Moreover, perfmon() access to those | |
3831 | * registers are centralized in this routine. The hardware | |
3832 | * does not modify the value of these registers, therefore, | |
3833 | * if we save them as they are written, we can avoid having | |
3834 | * to save them on context switch out. This is made possible | |
3835 | * by the fact that when perfmon uses debug registers, ptrace() | |
3836 | * won't be able to modify them concurrently. | |
3837 | */ | |
3838 | if (mode == PFM_CODE_RR) { | |
3839 | CTX_USED_IBR(ctx, rnum); | |
3840 | ||
3841 | if (can_access_pmu) { | |
3842 | ia64_set_ibr(rnum, dbreg.val); | |
3843 | ia64_dv_serialize_instruction(); | |
3844 | } | |
3845 | ||
3846 | ctx->ctx_ibrs[rnum] = dbreg.val; | |
3847 | ||
3848 | DPRINT(("write ibr%u=0x%lx used_ibrs=0x%x ld=%d apmu=%d\n", | |
3849 | rnum, dbreg.val, ctx->ctx_used_ibrs[0], is_loaded, can_access_pmu)); | |
3850 | } else { | |
3851 | CTX_USED_DBR(ctx, rnum); | |
3852 | ||
3853 | if (can_access_pmu) { | |
3854 | ia64_set_dbr(rnum, dbreg.val); | |
3855 | ia64_dv_serialize_data(); | |
3856 | } | |
3857 | ctx->ctx_dbrs[rnum] = dbreg.val; | |
3858 | ||
3859 | DPRINT(("write dbr%u=0x%lx used_dbrs=0x%x ld=%d apmu=%d\n", | |
3860 | rnum, dbreg.val, ctx->ctx_used_dbrs[0], is_loaded, can_access_pmu)); | |
3861 | } | |
3862 | } | |
3863 | ||
3864 | return 0; | |
3865 | ||
3866 | abort_mission: | |
3867 | /* | |
3868 | * in case it was our first attempt, we undo the global modifications | |
3869 | */ | |
3870 | if (first_time) { | |
3871 | LOCK_PFS(flags); | |
3872 | if (ctx->ctx_fl_system) { | |
3873 | pfm_sessions.pfs_sys_use_dbregs--; | |
3874 | } | |
3875 | UNLOCK_PFS(flags); | |
3876 | ctx->ctx_fl_using_dbreg = 0; | |
3877 | } | |
3878 | /* | |
3879 | * install error return flag | |
3880 | */ | |
3881 | PFM_REG_RETFLAG_SET(req->dbreg_flags, PFM_REG_RETFL_EINVAL); | |
3882 | ||
3883 | return ret; | |
3884 | } | |
3885 | ||
3886 | static int | |
3887 | pfm_write_ibrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3888 | { | |
3889 | return pfm_write_ibr_dbr(PFM_CODE_RR, ctx, arg, count, regs); | |
3890 | } | |
3891 | ||
3892 | static int | |
3893 | pfm_write_dbrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3894 | { | |
3895 | return pfm_write_ibr_dbr(PFM_DATA_RR, ctx, arg, count, regs); | |
3896 | } | |
3897 | ||
3898 | int | |
3899 | pfm_mod_write_ibrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) | |
3900 | { | |
3901 | pfm_context_t *ctx; | |
3902 | ||
3903 | if (req == NULL) return -EINVAL; | |
3904 | ||
3905 | ctx = GET_PMU_CTX(); | |
3906 | ||
3907 | if (ctx == NULL) return -EINVAL; | |
3908 | ||
3909 | /* | |
3910 | * for now limit to current task, which is enough when calling | |
3911 | * from overflow handler | |
3912 | */ | |
3913 | if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; | |
3914 | ||
3915 | return pfm_write_ibrs(ctx, req, nreq, regs); | |
3916 | } | |
3917 | EXPORT_SYMBOL(pfm_mod_write_ibrs); | |
3918 | ||
3919 | int | |
3920 | pfm_mod_write_dbrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) | |
3921 | { | |
3922 | pfm_context_t *ctx; | |
3923 | ||
3924 | if (req == NULL) return -EINVAL; | |
3925 | ||
3926 | ctx = GET_PMU_CTX(); | |
3927 | ||
3928 | if (ctx == NULL) return -EINVAL; | |
3929 | ||
3930 | /* | |
3931 | * for now limit to current task, which is enough when calling | |
3932 | * from overflow handler | |
3933 | */ | |
3934 | if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; | |
3935 | ||
3936 | return pfm_write_dbrs(ctx, req, nreq, regs); | |
3937 | } | |
3938 | EXPORT_SYMBOL(pfm_mod_write_dbrs); | |
3939 | ||
3940 | ||
3941 | static int | |
3942 | pfm_get_features(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3943 | { | |
3944 | pfarg_features_t *req = (pfarg_features_t *)arg; | |
3945 | ||
3946 | req->ft_version = PFM_VERSION; | |
3947 | return 0; | |
3948 | } | |
3949 | ||
3950 | static int | |
3951 | pfm_stop(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
3952 | { | |
3953 | struct pt_regs *tregs; | |
3954 | struct task_struct *task = PFM_CTX_TASK(ctx); | |
3955 | int state, is_system; | |
3956 | ||
3957 | state = ctx->ctx_state; | |
3958 | is_system = ctx->ctx_fl_system; | |
3959 | ||
3960 | /* | |
3961 | * context must be attached to issue the stop command (includes LOADED,MASKED,ZOMBIE) | |
3962 | */ | |
3963 | if (state == PFM_CTX_UNLOADED) return -EINVAL; | |
3964 | ||
3965 | /* | |
3966 | * In system wide and when the context is loaded, access can only happen | |
3967 | * when the caller is running on the CPU being monitored by the session. | |
3968 | * It does not have to be the owner (ctx_task) of the context per se. | |
3969 | */ | |
3970 | if (is_system && ctx->ctx_cpu != smp_processor_id()) { | |
3971 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
3972 | return -EBUSY; | |
3973 | } | |
3974 | DPRINT(("task [%d] ctx_state=%d is_system=%d\n", | |
19c5870c | 3975 | task_pid_nr(PFM_CTX_TASK(ctx)), |
1da177e4 LT |
3976 | state, |
3977 | is_system)); | |
3978 | /* | |
3979 | * in system mode, we need to update the PMU directly | |
3980 | * and the user level state of the caller, which may not | |
3981 | * necessarily be the creator of the context. | |
3982 | */ | |
3983 | if (is_system) { | |
3984 | /* | |
3985 | * Update local PMU first | |
3986 | * | |
3987 | * disable dcr pp | |
3988 | */ | |
3989 | ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP); | |
3990 | ia64_srlz_i(); | |
3991 | ||
3992 | /* | |
3993 | * update local cpuinfo | |
3994 | */ | |
3995 | PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP); | |
3996 | ||
3997 | /* | |
3998 | * stop monitoring, does srlz.i | |
3999 | */ | |
4000 | pfm_clear_psr_pp(); | |
4001 | ||
4002 | /* | |
4003 | * stop monitoring in the caller | |
4004 | */ | |
4005 | ia64_psr(regs)->pp = 0; | |
4006 | ||
4007 | return 0; | |
4008 | } | |
4009 | /* | |
4010 | * per-task mode | |
4011 | */ | |
4012 | ||
4013 | if (task == current) { | |
4014 | /* stop monitoring at kernel level */ | |
4015 | pfm_clear_psr_up(); | |
4016 | ||
4017 | /* | |
4018 | * stop monitoring at the user level | |
4019 | */ | |
4020 | ia64_psr(regs)->up = 0; | |
4021 | } else { | |
6450578f | 4022 | tregs = task_pt_regs(task); |
1da177e4 LT |
4023 | |
4024 | /* | |
4025 | * stop monitoring at the user level | |
4026 | */ | |
4027 | ia64_psr(tregs)->up = 0; | |
4028 | ||
4029 | /* | |
4030 | * monitoring disabled in kernel at next reschedule | |
4031 | */ | |
4032 | ctx->ctx_saved_psr_up = 0; | |
19c5870c | 4033 | DPRINT(("task=[%d]\n", task_pid_nr(task))); |
1da177e4 LT |
4034 | } |
4035 | return 0; | |
4036 | } | |
4037 | ||
4038 | ||
4039 | static int | |
4040 | pfm_start(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
4041 | { | |
4042 | struct pt_regs *tregs; | |
4043 | int state, is_system; | |
4044 | ||
4045 | state = ctx->ctx_state; | |
4046 | is_system = ctx->ctx_fl_system; | |
4047 | ||
4048 | if (state != PFM_CTX_LOADED) return -EINVAL; | |
4049 | ||
4050 | /* | |
4051 | * In system wide and when the context is loaded, access can only happen | |
4052 | * when the caller is running on the CPU being monitored by the session. | |
4053 | * It does not have to be the owner (ctx_task) of the context per se. | |
4054 | */ | |
4055 | if (is_system && ctx->ctx_cpu != smp_processor_id()) { | |
4056 | DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); | |
4057 | return -EBUSY; | |
4058 | } | |
4059 | ||
4060 | /* | |
4061 | * in system mode, we need to update the PMU directly | |
4062 | * and the user level state of the caller, which may not | |
4063 | * necessarily be the creator of the context. | |
4064 | */ | |
4065 | if (is_system) { | |
4066 | ||
4067 | /* | |
4068 | * set user level psr.pp for the caller | |
4069 | */ | |
4070 | ia64_psr(regs)->pp = 1; | |
4071 | ||
4072 | /* | |
4073 | * now update the local PMU and cpuinfo | |
4074 | */ | |
4075 | PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP); | |
4076 | ||
4077 | /* | |
4078 | * start monitoring at kernel level | |
4079 | */ | |
4080 | pfm_set_psr_pp(); | |
4081 | ||
4082 | /* enable dcr pp */ | |
4083 | ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP); | |
4084 | ia64_srlz_i(); | |
4085 | ||
4086 | return 0; | |
4087 | } | |
4088 | ||
4089 | /* | |
4090 | * per-process mode | |
4091 | */ | |
4092 | ||
4093 | if (ctx->ctx_task == current) { | |
4094 | ||
4095 | /* start monitoring at kernel level */ | |
4096 | pfm_set_psr_up(); | |
4097 | ||
4098 | /* | |
4099 | * activate monitoring at user level | |
4100 | */ | |
4101 | ia64_psr(regs)->up = 1; | |
4102 | ||
4103 | } else { | |
6450578f | 4104 | tregs = task_pt_regs(ctx->ctx_task); |
1da177e4 LT |
4105 | |
4106 | /* | |
4107 | * start monitoring at the kernel level the next | |
4108 | * time the task is scheduled | |
4109 | */ | |
4110 | ctx->ctx_saved_psr_up = IA64_PSR_UP; | |
4111 | ||
4112 | /* | |
4113 | * activate monitoring at user level | |
4114 | */ | |
4115 | ia64_psr(tregs)->up = 1; | |
4116 | } | |
4117 | return 0; | |
4118 | } | |
4119 | ||
4120 | static int | |
4121 | pfm_get_pmc_reset(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
4122 | { | |
4123 | pfarg_reg_t *req = (pfarg_reg_t *)arg; | |
4124 | unsigned int cnum; | |
4125 | int i; | |
4126 | int ret = -EINVAL; | |
4127 | ||
4128 | for (i = 0; i < count; i++, req++) { | |
4129 | ||
4130 | cnum = req->reg_num; | |
4131 | ||
4132 | if (!PMC_IS_IMPL(cnum)) goto abort_mission; | |
4133 | ||
4134 | req->reg_value = PMC_DFL_VAL(cnum); | |
4135 | ||
4136 | PFM_REG_RETFLAG_SET(req->reg_flags, 0); | |
4137 | ||
4138 | DPRINT(("pmc_reset_val pmc[%u]=0x%lx\n", cnum, req->reg_value)); | |
4139 | } | |
4140 | return 0; | |
4141 | ||
4142 | abort_mission: | |
4143 | PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); | |
4144 | return ret; | |
4145 | } | |
4146 | ||
4147 | static int | |
4148 | pfm_check_task_exist(pfm_context_t *ctx) | |
4149 | { | |
4150 | struct task_struct *g, *t; | |
4151 | int ret = -ESRCH; | |
4152 | ||
4153 | read_lock(&tasklist_lock); | |
4154 | ||
4155 | do_each_thread (g, t) { | |
4156 | if (t->thread.pfm_context == ctx) { | |
4157 | ret = 0; | |
6794c752 | 4158 | goto out; |
1da177e4 LT |
4159 | } |
4160 | } while_each_thread (g, t); | |
6794c752 | 4161 | out: |
1da177e4 LT |
4162 | read_unlock(&tasklist_lock); |
4163 | ||
4164 | DPRINT(("pfm_check_task_exist: ret=%d ctx=%p\n", ret, ctx)); | |
4165 | ||
4166 | return ret; | |
4167 | } | |
4168 | ||
4169 | static int | |
4170 | pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
4171 | { | |
4172 | struct task_struct *task; | |
4173 | struct thread_struct *thread; | |
4174 | struct pfm_context_t *old; | |
4175 | unsigned long flags; | |
4176 | #ifndef CONFIG_SMP | |
4177 | struct task_struct *owner_task = NULL; | |
4178 | #endif | |
4179 | pfarg_load_t *req = (pfarg_load_t *)arg; | |
4180 | unsigned long *pmcs_source, *pmds_source; | |
4181 | int the_cpu; | |
4182 | int ret = 0; | |
4183 | int state, is_system, set_dbregs = 0; | |
4184 | ||
4185 | state = ctx->ctx_state; | |
4186 | is_system = ctx->ctx_fl_system; | |
4187 | /* | |
4188 | * can only load from unloaded or terminated state | |
4189 | */ | |
4190 | if (state != PFM_CTX_UNLOADED) { | |
4191 | DPRINT(("cannot load to [%d], invalid ctx_state=%d\n", | |
4192 | req->load_pid, | |
4193 | ctx->ctx_state)); | |
a5a70b75 | 4194 | return -EBUSY; |
1da177e4 LT |
4195 | } |
4196 | ||
4197 | DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg)); | |
4198 | ||
4199 | if (CTX_OVFL_NOBLOCK(ctx) == 0 && req->load_pid == current->pid) { | |
4200 | DPRINT(("cannot use blocking mode on self\n")); | |
4201 | return -EINVAL; | |
4202 | } | |
4203 | ||
4204 | ret = pfm_get_task(ctx, req->load_pid, &task); | |
4205 | if (ret) { | |
4206 | DPRINT(("load_pid [%d] get_task=%d\n", req->load_pid, ret)); | |
4207 | return ret; | |
4208 | } | |
4209 | ||
4210 | ret = -EINVAL; | |
4211 | ||
4212 | /* | |
4213 | * system wide is self monitoring only | |
4214 | */ | |
4215 | if (is_system && task != current) { | |
4216 | DPRINT(("system wide is self monitoring only load_pid=%d\n", | |
4217 | req->load_pid)); | |
4218 | goto error; | |
4219 | } | |
4220 | ||
4221 | thread = &task->thread; | |
4222 | ||
4223 | ret = 0; | |
4224 | /* | |
4225 | * cannot load a context which is using range restrictions, | |
4226 | * into a task that is being debugged. | |
4227 | */ | |
4228 | if (ctx->ctx_fl_using_dbreg) { | |
4229 | if (thread->flags & IA64_THREAD_DBG_VALID) { | |
4230 | ret = -EBUSY; | |
4231 | DPRINT(("load_pid [%d] task is debugged, cannot load range restrictions\n", req->load_pid)); | |
4232 | goto error; | |
4233 | } | |
4234 | LOCK_PFS(flags); | |
4235 | ||
4236 | if (is_system) { | |
4237 | if (pfm_sessions.pfs_ptrace_use_dbregs) { | |
19c5870c AD |
4238 | DPRINT(("cannot load [%d] dbregs in use\n", |
4239 | task_pid_nr(task))); | |
1da177e4 LT |
4240 | ret = -EBUSY; |
4241 | } else { | |
4242 | pfm_sessions.pfs_sys_use_dbregs++; | |
19c5870c | 4243 | DPRINT(("load [%d] increased sys_use_dbreg=%u\n", task_pid_nr(task), pfm_sessions.pfs_sys_use_dbregs)); |
1da177e4 LT |
4244 | set_dbregs = 1; |
4245 | } | |
4246 | } | |
4247 | ||
4248 | UNLOCK_PFS(flags); | |
4249 | ||
4250 | if (ret) goto error; | |
4251 | } | |
4252 | ||
4253 | /* | |
4254 | * SMP system-wide monitoring implies self-monitoring. | |
4255 | * | |
4256 | * The programming model expects the task to | |
4257 | * be pinned on a CPU throughout the session. | |
4258 | * Here we take note of the current CPU at the | |
4259 | * time the context is loaded. No call from | |
4260 | * another CPU will be allowed. | |
4261 | * | |
4262 | * The pinning via shed_setaffinity() | |
4263 | * must be done by the calling task prior | |
4264 | * to this call. | |
4265 | * | |
4266 | * systemwide: keep track of CPU this session is supposed to run on | |
4267 | */ | |
4268 | the_cpu = ctx->ctx_cpu = smp_processor_id(); | |
4269 | ||
4270 | ret = -EBUSY; | |
4271 | /* | |
4272 | * now reserve the session | |
4273 | */ | |
4274 | ret = pfm_reserve_session(current, is_system, the_cpu); | |
4275 | if (ret) goto error; | |
4276 | ||
4277 | /* | |
4278 | * task is necessarily stopped at this point. | |
4279 | * | |
4280 | * If the previous context was zombie, then it got removed in | |
4281 | * pfm_save_regs(). Therefore we should not see it here. | |
4282 | * If we see a context, then this is an active context | |
4283 | * | |
4284 | * XXX: needs to be atomic | |
4285 | */ | |
4286 | DPRINT(("before cmpxchg() old_ctx=%p new_ctx=%p\n", | |
4287 | thread->pfm_context, ctx)); | |
4288 | ||
6bf11e8c | 4289 | ret = -EBUSY; |
1da177e4 LT |
4290 | old = ia64_cmpxchg(acq, &thread->pfm_context, NULL, ctx, sizeof(pfm_context_t *)); |
4291 | if (old != NULL) { | |
4292 | DPRINT(("load_pid [%d] already has a context\n", req->load_pid)); | |
4293 | goto error_unres; | |
4294 | } | |
4295 | ||
4296 | pfm_reset_msgq(ctx); | |
4297 | ||
4298 | ctx->ctx_state = PFM_CTX_LOADED; | |
4299 | ||
4300 | /* | |
4301 | * link context to task | |
4302 | */ | |
4303 | ctx->ctx_task = task; | |
4304 | ||
4305 | if (is_system) { | |
4306 | /* | |
4307 | * we load as stopped | |
4308 | */ | |
4309 | PFM_CPUINFO_SET(PFM_CPUINFO_SYST_WIDE); | |
4310 | PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP); | |
4311 | ||
4312 | if (ctx->ctx_fl_excl_idle) PFM_CPUINFO_SET(PFM_CPUINFO_EXCL_IDLE); | |
4313 | } else { | |
4314 | thread->flags |= IA64_THREAD_PM_VALID; | |
4315 | } | |
4316 | ||
4317 | /* | |
4318 | * propagate into thread-state | |
4319 | */ | |
4320 | pfm_copy_pmds(task, ctx); | |
4321 | pfm_copy_pmcs(task, ctx); | |
4322 | ||
35589a8f KA |
4323 | pmcs_source = ctx->th_pmcs; |
4324 | pmds_source = ctx->th_pmds; | |
1da177e4 LT |
4325 | |
4326 | /* | |
4327 | * always the case for system-wide | |
4328 | */ | |
4329 | if (task == current) { | |
4330 | ||
4331 | if (is_system == 0) { | |
4332 | ||
4333 | /* allow user level control */ | |
4334 | ia64_psr(regs)->sp = 0; | |
19c5870c | 4335 | DPRINT(("clearing psr.sp for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
4336 | |
4337 | SET_LAST_CPU(ctx, smp_processor_id()); | |
4338 | INC_ACTIVATION(); | |
4339 | SET_ACTIVATION(ctx); | |
4340 | #ifndef CONFIG_SMP | |
4341 | /* | |
4342 | * push the other task out, if any | |
4343 | */ | |
4344 | owner_task = GET_PMU_OWNER(); | |
4345 | if (owner_task) pfm_lazy_save_regs(owner_task); | |
4346 | #endif | |
4347 | } | |
4348 | /* | |
4349 | * load all PMD from ctx to PMU (as opposed to thread state) | |
4350 | * restore all PMC from ctx to PMU | |
4351 | */ | |
4352 | pfm_restore_pmds(pmds_source, ctx->ctx_all_pmds[0]); | |
4353 | pfm_restore_pmcs(pmcs_source, ctx->ctx_all_pmcs[0]); | |
4354 | ||
4355 | ctx->ctx_reload_pmcs[0] = 0UL; | |
4356 | ctx->ctx_reload_pmds[0] = 0UL; | |
4357 | ||
4358 | /* | |
4359 | * guaranteed safe by earlier check against DBG_VALID | |
4360 | */ | |
4361 | if (ctx->ctx_fl_using_dbreg) { | |
4362 | pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); | |
4363 | pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); | |
4364 | } | |
4365 | /* | |
4366 | * set new ownership | |
4367 | */ | |
4368 | SET_PMU_OWNER(task, ctx); | |
4369 | ||
19c5870c | 4370 | DPRINT(("context loaded on PMU for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
4371 | } else { |
4372 | /* | |
4373 | * when not current, task MUST be stopped, so this is safe | |
4374 | */ | |
6450578f | 4375 | regs = task_pt_regs(task); |
1da177e4 LT |
4376 | |
4377 | /* force a full reload */ | |
4378 | ctx->ctx_last_activation = PFM_INVALID_ACTIVATION; | |
4379 | SET_LAST_CPU(ctx, -1); | |
4380 | ||
4381 | /* initial saved psr (stopped) */ | |
4382 | ctx->ctx_saved_psr_up = 0UL; | |
4383 | ia64_psr(regs)->up = ia64_psr(regs)->pp = 0; | |
4384 | } | |
4385 | ||
4386 | ret = 0; | |
4387 | ||
4388 | error_unres: | |
4389 | if (ret) pfm_unreserve_session(ctx, ctx->ctx_fl_system, the_cpu); | |
4390 | error: | |
4391 | /* | |
4392 | * we must undo the dbregs setting (for system-wide) | |
4393 | */ | |
4394 | if (ret && set_dbregs) { | |
4395 | LOCK_PFS(flags); | |
4396 | pfm_sessions.pfs_sys_use_dbregs--; | |
4397 | UNLOCK_PFS(flags); | |
4398 | } | |
4399 | /* | |
4400 | * release task, there is now a link with the context | |
4401 | */ | |
4402 | if (is_system == 0 && task != current) { | |
4403 | pfm_put_task(task); | |
4404 | ||
4405 | if (ret == 0) { | |
4406 | ret = pfm_check_task_exist(ctx); | |
4407 | if (ret) { | |
4408 | ctx->ctx_state = PFM_CTX_UNLOADED; | |
4409 | ctx->ctx_task = NULL; | |
4410 | } | |
4411 | } | |
4412 | } | |
4413 | return ret; | |
4414 | } | |
4415 | ||
4416 | /* | |
4417 | * in this function, we do not need to increase the use count | |
4418 | * for the task via get_task_struct(), because we hold the | |
4419 | * context lock. If the task were to disappear while having | |
4420 | * a context attached, it would go through pfm_exit_thread() | |
4421 | * which also grabs the context lock and would therefore be blocked | |
4422 | * until we are here. | |
4423 | */ | |
4424 | static void pfm_flush_pmds(struct task_struct *, pfm_context_t *ctx); | |
4425 | ||
4426 | static int | |
4427 | pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) | |
4428 | { | |
4429 | struct task_struct *task = PFM_CTX_TASK(ctx); | |
4430 | struct pt_regs *tregs; | |
4431 | int prev_state, is_system; | |
4432 | int ret; | |
4433 | ||
19c5870c | 4434 | DPRINT(("ctx_state=%d task [%d]\n", ctx->ctx_state, task ? task_pid_nr(task) : -1)); |
1da177e4 LT |
4435 | |
4436 | prev_state = ctx->ctx_state; | |
4437 | is_system = ctx->ctx_fl_system; | |
4438 | ||
4439 | /* | |
4440 | * unload only when necessary | |
4441 | */ | |
4442 | if (prev_state == PFM_CTX_UNLOADED) { | |
4443 | DPRINT(("ctx_state=%d, nothing to do\n", prev_state)); | |
4444 | return 0; | |
4445 | } | |
4446 | ||
4447 | /* | |
4448 | * clear psr and dcr bits | |
4449 | */ | |
4450 | ret = pfm_stop(ctx, NULL, 0, regs); | |
4451 | if (ret) return ret; | |
4452 | ||
4453 | ctx->ctx_state = PFM_CTX_UNLOADED; | |
4454 | ||
4455 | /* | |
4456 | * in system mode, we need to update the PMU directly | |
4457 | * and the user level state of the caller, which may not | |
4458 | * necessarily be the creator of the context. | |
4459 | */ | |
4460 | if (is_system) { | |
4461 | ||
4462 | /* | |
4463 | * Update cpuinfo | |
4464 | * | |
4465 | * local PMU is taken care of in pfm_stop() | |
4466 | */ | |
4467 | PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE); | |
4468 | PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE); | |
4469 | ||
4470 | /* | |
4471 | * save PMDs in context | |
4472 | * release ownership | |
4473 | */ | |
4474 | pfm_flush_pmds(current, ctx); | |
4475 | ||
4476 | /* | |
4477 | * at this point we are done with the PMU | |
4478 | * so we can unreserve the resource. | |
4479 | */ | |
4480 | if (prev_state != PFM_CTX_ZOMBIE) | |
4481 | pfm_unreserve_session(ctx, 1 , ctx->ctx_cpu); | |
4482 | ||
4483 | /* | |
4484 | * disconnect context from task | |
4485 | */ | |
4486 | task->thread.pfm_context = NULL; | |
4487 | /* | |
4488 | * disconnect task from context | |
4489 | */ | |
4490 | ctx->ctx_task = NULL; | |
4491 | ||
4492 | /* | |
4493 | * There is nothing more to cleanup here. | |
4494 | */ | |
4495 | return 0; | |
4496 | } | |
4497 | ||
4498 | /* | |
4499 | * per-task mode | |
4500 | */ | |
6450578f | 4501 | tregs = task == current ? regs : task_pt_regs(task); |
1da177e4 LT |
4502 | |
4503 | if (task == current) { | |
4504 | /* | |
4505 | * cancel user level control | |
4506 | */ | |
4507 | ia64_psr(regs)->sp = 1; | |
4508 | ||
19c5870c | 4509 | DPRINT(("setting psr.sp for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
4510 | } |
4511 | /* | |
4512 | * save PMDs to context | |
4513 | * release ownership | |
4514 | */ | |
4515 | pfm_flush_pmds(task, ctx); | |
4516 | ||
4517 | /* | |
4518 | * at this point we are done with the PMU | |
4519 | * so we can unreserve the resource. | |
4520 | * | |
4521 | * when state was ZOMBIE, we have already unreserved. | |
4522 | */ | |
4523 | if (prev_state != PFM_CTX_ZOMBIE) | |
4524 | pfm_unreserve_session(ctx, 0 , ctx->ctx_cpu); | |
4525 | ||
4526 | /* | |
4527 | * reset activation counter and psr | |
4528 | */ | |
4529 | ctx->ctx_last_activation = PFM_INVALID_ACTIVATION; | |
4530 | SET_LAST_CPU(ctx, -1); | |
4531 | ||
4532 | /* | |
4533 | * PMU state will not be restored | |
4534 | */ | |
4535 | task->thread.flags &= ~IA64_THREAD_PM_VALID; | |
4536 | ||
4537 | /* | |
4538 | * break links between context and task | |
4539 | */ | |
4540 | task->thread.pfm_context = NULL; | |
4541 | ctx->ctx_task = NULL; | |
4542 | ||
4543 | PFM_SET_WORK_PENDING(task, 0); | |
4544 | ||
4545 | ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE; | |
4546 | ctx->ctx_fl_can_restart = 0; | |
4547 | ctx->ctx_fl_going_zombie = 0; | |
4548 | ||
19c5870c | 4549 | DPRINT(("disconnected [%d] from context\n", task_pid_nr(task))); |
1da177e4 LT |
4550 | |
4551 | return 0; | |
4552 | } | |
4553 | ||
4554 | ||
4555 | /* | |
4556 | * called only from exit_thread(): task == current | |
4557 | * we come here only if current has a context attached (loaded or masked) | |
4558 | */ | |
4559 | void | |
4560 | pfm_exit_thread(struct task_struct *task) | |
4561 | { | |
4562 | pfm_context_t *ctx; | |
4563 | unsigned long flags; | |
6450578f | 4564 | struct pt_regs *regs = task_pt_regs(task); |
1da177e4 LT |
4565 | int ret, state; |
4566 | int free_ok = 0; | |
4567 | ||
4568 | ctx = PFM_GET_CTX(task); | |
4569 | ||
4570 | PROTECT_CTX(ctx, flags); | |
4571 | ||
19c5870c | 4572 | DPRINT(("state=%d task [%d]\n", ctx->ctx_state, task_pid_nr(task))); |
1da177e4 LT |
4573 | |
4574 | state = ctx->ctx_state; | |
4575 | switch(state) { | |
4576 | case PFM_CTX_UNLOADED: | |
4577 | /* | |
72fdbdce | 4578 | * only comes to this function if pfm_context is not NULL, i.e., cannot |
1da177e4 LT |
4579 | * be in unloaded state |
4580 | */ | |
19c5870c | 4581 | printk(KERN_ERR "perfmon: pfm_exit_thread [%d] ctx unloaded\n", task_pid_nr(task)); |
1da177e4 LT |
4582 | break; |
4583 | case PFM_CTX_LOADED: | |
4584 | case PFM_CTX_MASKED: | |
4585 | ret = pfm_context_unload(ctx, NULL, 0, regs); | |
4586 | if (ret) { | |
19c5870c | 4587 | printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task_pid_nr(task), state, ret); |
1da177e4 LT |
4588 | } |
4589 | DPRINT(("ctx unloaded for current state was %d\n", state)); | |
4590 | ||
4591 | pfm_end_notify_user(ctx); | |
4592 | break; | |
4593 | case PFM_CTX_ZOMBIE: | |
4594 | ret = pfm_context_unload(ctx, NULL, 0, regs); | |
4595 | if (ret) { | |
19c5870c | 4596 | printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task_pid_nr(task), state, ret); |
1da177e4 LT |
4597 | } |
4598 | free_ok = 1; | |
4599 | break; | |
4600 | default: | |
19c5870c | 4601 | printk(KERN_ERR "perfmon: pfm_exit_thread [%d] unexpected state=%d\n", task_pid_nr(task), state); |
1da177e4 LT |
4602 | break; |
4603 | } | |
4604 | UNPROTECT_CTX(ctx, flags); | |
4605 | ||
4606 | { u64 psr = pfm_get_psr(); | |
4607 | BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP)); | |
4608 | BUG_ON(GET_PMU_OWNER()); | |
4609 | BUG_ON(ia64_psr(regs)->up); | |
4610 | BUG_ON(ia64_psr(regs)->pp); | |
4611 | } | |
4612 | ||
4613 | /* | |
4614 | * All memory free operations (especially for vmalloc'ed memory) | |
4615 | * MUST be done with interrupts ENABLED. | |
4616 | */ | |
4617 | if (free_ok) pfm_context_free(ctx); | |
4618 | } | |
4619 | ||
4620 | /* | |
4621 | * functions MUST be listed in the increasing order of their index (see permfon.h) | |
4622 | */ | |
4623 | #define PFM_CMD(name, flags, arg_count, arg_type, getsz) { name, #name, flags, arg_count, sizeof(arg_type), getsz } | |
4624 | #define PFM_CMD_S(name, flags) { name, #name, flags, 0, 0, NULL } | |
4625 | #define PFM_CMD_PCLRWS (PFM_CMD_FD|PFM_CMD_ARG_RW|PFM_CMD_STOP) | |
4626 | #define PFM_CMD_PCLRW (PFM_CMD_FD|PFM_CMD_ARG_RW) | |
4627 | #define PFM_CMD_NONE { NULL, "no-cmd", 0, 0, 0, NULL} | |
4628 | ||
4629 | static pfm_cmd_desc_t pfm_cmd_tab[]={ | |
4630 | /* 0 */PFM_CMD_NONE, | |
4631 | /* 1 */PFM_CMD(pfm_write_pmcs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), | |
4632 | /* 2 */PFM_CMD(pfm_write_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), | |
4633 | /* 3 */PFM_CMD(pfm_read_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), | |
4634 | /* 4 */PFM_CMD_S(pfm_stop, PFM_CMD_PCLRWS), | |
4635 | /* 5 */PFM_CMD_S(pfm_start, PFM_CMD_PCLRWS), | |
4636 | /* 6 */PFM_CMD_NONE, | |
4637 | /* 7 */PFM_CMD_NONE, | |
4638 | /* 8 */PFM_CMD(pfm_context_create, PFM_CMD_ARG_RW, 1, pfarg_context_t, pfm_ctx_getsize), | |
4639 | /* 9 */PFM_CMD_NONE, | |
4640 | /* 10 */PFM_CMD_S(pfm_restart, PFM_CMD_PCLRW), | |
4641 | /* 11 */PFM_CMD_NONE, | |
4642 | /* 12 */PFM_CMD(pfm_get_features, PFM_CMD_ARG_RW, 1, pfarg_features_t, NULL), | |
4643 | /* 13 */PFM_CMD(pfm_debug, 0, 1, unsigned int, NULL), | |
4644 | /* 14 */PFM_CMD_NONE, | |
4645 | /* 15 */PFM_CMD(pfm_get_pmc_reset, PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), | |
4646 | /* 16 */PFM_CMD(pfm_context_load, PFM_CMD_PCLRWS, 1, pfarg_load_t, NULL), | |
4647 | /* 17 */PFM_CMD_S(pfm_context_unload, PFM_CMD_PCLRWS), | |
4648 | /* 18 */PFM_CMD_NONE, | |
4649 | /* 19 */PFM_CMD_NONE, | |
4650 | /* 20 */PFM_CMD_NONE, | |
4651 | /* 21 */PFM_CMD_NONE, | |
4652 | /* 22 */PFM_CMD_NONE, | |
4653 | /* 23 */PFM_CMD_NONE, | |
4654 | /* 24 */PFM_CMD_NONE, | |
4655 | /* 25 */PFM_CMD_NONE, | |
4656 | /* 26 */PFM_CMD_NONE, | |
4657 | /* 27 */PFM_CMD_NONE, | |
4658 | /* 28 */PFM_CMD_NONE, | |
4659 | /* 29 */PFM_CMD_NONE, | |
4660 | /* 30 */PFM_CMD_NONE, | |
4661 | /* 31 */PFM_CMD_NONE, | |
4662 | /* 32 */PFM_CMD(pfm_write_ibrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL), | |
4663 | /* 33 */PFM_CMD(pfm_write_dbrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL) | |
4664 | }; | |
4665 | #define PFM_CMD_COUNT (sizeof(pfm_cmd_tab)/sizeof(pfm_cmd_desc_t)) | |
4666 | ||
4667 | static int | |
4668 | pfm_check_task_state(pfm_context_t *ctx, int cmd, unsigned long flags) | |
4669 | { | |
4670 | struct task_struct *task; | |
4671 | int state, old_state; | |
4672 | ||
4673 | recheck: | |
4674 | state = ctx->ctx_state; | |
4675 | task = ctx->ctx_task; | |
4676 | ||
4677 | if (task == NULL) { | |
4678 | DPRINT(("context %d no task, state=%d\n", ctx->ctx_fd, state)); | |
4679 | return 0; | |
4680 | } | |
4681 | ||
4682 | DPRINT(("context %d state=%d [%d] task_state=%ld must_stop=%d\n", | |
4683 | ctx->ctx_fd, | |
4684 | state, | |
19c5870c | 4685 | task_pid_nr(task), |
1da177e4 LT |
4686 | task->state, PFM_CMD_STOPPED(cmd))); |
4687 | ||
4688 | /* | |
4689 | * self-monitoring always ok. | |
4690 | * | |
4691 | * for system-wide the caller can either be the creator of the | |
4692 | * context (to one to which the context is attached to) OR | |
4693 | * a task running on the same CPU as the session. | |
4694 | */ | |
4695 | if (task == current || ctx->ctx_fl_system) return 0; | |
4696 | ||
4697 | /* | |
a5a70b75 | 4698 | * we are monitoring another thread |
1da177e4 | 4699 | */ |
a5a70b75 | 4700 | switch(state) { |
4701 | case PFM_CTX_UNLOADED: | |
4702 | /* | |
4703 | * if context is UNLOADED we are safe to go | |
4704 | */ | |
4705 | return 0; | |
4706 | case PFM_CTX_ZOMBIE: | |
4707 | /* | |
4708 | * no command can operate on a zombie context | |
4709 | */ | |
4710 | DPRINT(("cmd %d state zombie cannot operate on context\n", cmd)); | |
4711 | return -EINVAL; | |
4712 | case PFM_CTX_MASKED: | |
4713 | /* | |
4714 | * PMU state has been saved to software even though | |
4715 | * the thread may still be running. | |
4716 | */ | |
4717 | if (cmd != PFM_UNLOAD_CONTEXT) return 0; | |
1da177e4 LT |
4718 | } |
4719 | ||
4720 | /* | |
4721 | * context is LOADED or MASKED. Some commands may need to have | |
4722 | * the task stopped. | |
4723 | * | |
4724 | * We could lift this restriction for UP but it would mean that | |
4725 | * the user has no guarantee the task would not run between | |
4726 | * two successive calls to perfmonctl(). That's probably OK. | |
4727 | * If this user wants to ensure the task does not run, then | |
4728 | * the task must be stopped. | |
4729 | */ | |
4730 | if (PFM_CMD_STOPPED(cmd)) { | |
21498223 | 4731 | if (!task_is_stopped_or_traced(task)) { |
19c5870c | 4732 | DPRINT(("[%d] task not in stopped state\n", task_pid_nr(task))); |
1da177e4 LT |
4733 | return -EBUSY; |
4734 | } | |
4735 | /* | |
4736 | * task is now stopped, wait for ctxsw out | |
4737 | * | |
4738 | * This is an interesting point in the code. | |
4739 | * We need to unprotect the context because | |
4740 | * the pfm_save_regs() routines needs to grab | |
4741 | * the same lock. There are danger in doing | |
4742 | * this because it leaves a window open for | |
4743 | * another task to get access to the context | |
4744 | * and possibly change its state. The one thing | |
4745 | * that is not possible is for the context to disappear | |
4746 | * because we are protected by the VFS layer, i.e., | |
4747 | * get_fd()/put_fd(). | |
4748 | */ | |
4749 | old_state = state; | |
4750 | ||
4751 | UNPROTECT_CTX(ctx, flags); | |
4752 | ||
85ba2d86 | 4753 | wait_task_inactive(task, 0); |
1da177e4 LT |
4754 | |
4755 | PROTECT_CTX(ctx, flags); | |
4756 | ||
4757 | /* | |
4758 | * we must recheck to verify if state has changed | |
4759 | */ | |
4760 | if (ctx->ctx_state != old_state) { | |
4761 | DPRINT(("old_state=%d new_state=%d\n", old_state, ctx->ctx_state)); | |
4762 | goto recheck; | |
4763 | } | |
4764 | } | |
4765 | return 0; | |
4766 | } | |
4767 | ||
4768 | /* | |
4769 | * system-call entry point (must return long) | |
4770 | */ | |
4771 | asmlinkage long | |
4772 | sys_perfmonctl (int fd, int cmd, void __user *arg, int count) | |
4773 | { | |
2903ff01 | 4774 | struct fd f = {NULL, 0}; |
1da177e4 LT |
4775 | pfm_context_t *ctx = NULL; |
4776 | unsigned long flags = 0UL; | |
4777 | void *args_k = NULL; | |
4778 | long ret; /* will expand int return types */ | |
4779 | size_t base_sz, sz, xtra_sz = 0; | |
4780 | int narg, completed_args = 0, call_made = 0, cmd_flags; | |
4781 | int (*func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); | |
4782 | int (*getsize)(void *arg, size_t *sz); | |
4783 | #define PFM_MAX_ARGSIZE 4096 | |
4784 | ||
4785 | /* | |
4786 | * reject any call if perfmon was disabled at initialization | |
4787 | */ | |
4788 | if (unlikely(pmu_conf == NULL)) return -ENOSYS; | |
4789 | ||
4790 | if (unlikely(cmd < 0 || cmd >= PFM_CMD_COUNT)) { | |
4791 | DPRINT(("invalid cmd=%d\n", cmd)); | |
4792 | return -EINVAL; | |
4793 | } | |
4794 | ||
4795 | func = pfm_cmd_tab[cmd].cmd_func; | |
4796 | narg = pfm_cmd_tab[cmd].cmd_narg; | |
4797 | base_sz = pfm_cmd_tab[cmd].cmd_argsize; | |
4798 | getsize = pfm_cmd_tab[cmd].cmd_getsize; | |
4799 | cmd_flags = pfm_cmd_tab[cmd].cmd_flags; | |
4800 | ||
4801 | if (unlikely(func == NULL)) { | |
4802 | DPRINT(("invalid cmd=%d\n", cmd)); | |
4803 | return -EINVAL; | |
4804 | } | |
4805 | ||
4806 | DPRINT(("cmd=%s idx=%d narg=0x%x argsz=%lu count=%d\n", | |
4807 | PFM_CMD_NAME(cmd), | |
4808 | cmd, | |
4809 | narg, | |
4810 | base_sz, | |
4811 | count)); | |
4812 | ||
4813 | /* | |
4814 | * check if number of arguments matches what the command expects | |
4815 | */ | |
4816 | if (unlikely((narg == PFM_CMD_ARG_MANY && count <= 0) || (narg > 0 && narg != count))) | |
4817 | return -EINVAL; | |
4818 | ||
4819 | restart_args: | |
4820 | sz = xtra_sz + base_sz*count; | |
4821 | /* | |
4822 | * limit abuse to min page size | |
4823 | */ | |
4824 | if (unlikely(sz > PFM_MAX_ARGSIZE)) { | |
19c5870c | 4825 | printk(KERN_ERR "perfmon: [%d] argument too big %lu\n", task_pid_nr(current), sz); |
1da177e4 LT |
4826 | return -E2BIG; |
4827 | } | |
4828 | ||
4829 | /* | |
4830 | * allocate default-sized argument buffer | |
4831 | */ | |
4832 | if (likely(count && args_k == NULL)) { | |
4833 | args_k = kmalloc(PFM_MAX_ARGSIZE, GFP_KERNEL); | |
4834 | if (args_k == NULL) return -ENOMEM; | |
4835 | } | |
4836 | ||
4837 | ret = -EFAULT; | |
4838 | ||
4839 | /* | |
4840 | * copy arguments | |
4841 | * | |
4842 | * assume sz = 0 for command without parameters | |
4843 | */ | |
4844 | if (sz && copy_from_user(args_k, arg, sz)) { | |
4845 | DPRINT(("cannot copy_from_user %lu bytes @%p\n", sz, arg)); | |
4846 | goto error_args; | |
4847 | } | |
4848 | ||
4849 | /* | |
4850 | * check if command supports extra parameters | |
4851 | */ | |
4852 | if (completed_args == 0 && getsize) { | |
4853 | /* | |
4854 | * get extra parameters size (based on main argument) | |
4855 | */ | |
4856 | ret = (*getsize)(args_k, &xtra_sz); | |
4857 | if (ret) goto error_args; | |
4858 | ||
4859 | completed_args = 1; | |
4860 | ||
4861 | DPRINT(("restart_args sz=%lu xtra_sz=%lu\n", sz, xtra_sz)); | |
4862 | ||
4863 | /* retry if necessary */ | |
4864 | if (likely(xtra_sz)) goto restart_args; | |
4865 | } | |
4866 | ||
4867 | if (unlikely((cmd_flags & PFM_CMD_FD) == 0)) goto skip_fd; | |
4868 | ||
4869 | ret = -EBADF; | |
4870 | ||
2903ff01 AV |
4871 | f = fdget(fd); |
4872 | if (unlikely(f.file == NULL)) { | |
1da177e4 LT |
4873 | DPRINT(("invalid fd %d\n", fd)); |
4874 | goto error_args; | |
4875 | } | |
2903ff01 | 4876 | if (unlikely(PFM_IS_FILE(f.file) == 0)) { |
1da177e4 LT |
4877 | DPRINT(("fd %d not related to perfmon\n", fd)); |
4878 | goto error_args; | |
4879 | } | |
4880 | ||
2903ff01 | 4881 | ctx = f.file->private_data; |
1da177e4 LT |
4882 | if (unlikely(ctx == NULL)) { |
4883 | DPRINT(("no context for fd %d\n", fd)); | |
4884 | goto error_args; | |
4885 | } | |
4886 | prefetch(&ctx->ctx_state); | |
4887 | ||
4888 | PROTECT_CTX(ctx, flags); | |
4889 | ||
4890 | /* | |
4891 | * check task is stopped | |
4892 | */ | |
4893 | ret = pfm_check_task_state(ctx, cmd, flags); | |
4894 | if (unlikely(ret)) goto abort_locked; | |
4895 | ||
4896 | skip_fd: | |
6450578f | 4897 | ret = (*func)(ctx, args_k, count, task_pt_regs(current)); |
1da177e4 LT |
4898 | |
4899 | call_made = 1; | |
4900 | ||
4901 | abort_locked: | |
4902 | if (likely(ctx)) { | |
4903 | DPRINT(("context unlocked\n")); | |
4904 | UNPROTECT_CTX(ctx, flags); | |
1da177e4 LT |
4905 | } |
4906 | ||
4907 | /* copy argument back to user, if needed */ | |
4908 | if (call_made && PFM_CMD_RW_ARG(cmd) && copy_to_user(arg, args_k, base_sz*count)) ret = -EFAULT; | |
4909 | ||
4910 | error_args: | |
2903ff01 AV |
4911 | if (f.file) |
4912 | fdput(f); | |
b8444d00 | 4913 | |
b2325fe1 | 4914 | kfree(args_k); |
1da177e4 LT |
4915 | |
4916 | DPRINT(("cmd=%s ret=%ld\n", PFM_CMD_NAME(cmd), ret)); | |
4917 | ||
4918 | return ret; | |
4919 | } | |
4920 | ||
4921 | static void | |
4922 | pfm_resume_after_ovfl(pfm_context_t *ctx, unsigned long ovfl_regs, struct pt_regs *regs) | |
4923 | { | |
4924 | pfm_buffer_fmt_t *fmt = ctx->ctx_buf_fmt; | |
4925 | pfm_ovfl_ctrl_t rst_ctrl; | |
4926 | int state; | |
4927 | int ret = 0; | |
4928 | ||
4929 | state = ctx->ctx_state; | |
4930 | /* | |
4931 | * Unlock sampling buffer and reset index atomically | |
4932 | * XXX: not really needed when blocking | |
4933 | */ | |
4934 | if (CTX_HAS_SMPL(ctx)) { | |
4935 | ||
4936 | rst_ctrl.bits.mask_monitoring = 0; | |
4937 | rst_ctrl.bits.reset_ovfl_pmds = 0; | |
4938 | ||
4939 | if (state == PFM_CTX_LOADED) | |
4940 | ret = pfm_buf_fmt_restart_active(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs); | |
4941 | else | |
4942 | ret = pfm_buf_fmt_restart(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs); | |
4943 | } else { | |
4944 | rst_ctrl.bits.mask_monitoring = 0; | |
4945 | rst_ctrl.bits.reset_ovfl_pmds = 1; | |
4946 | } | |
4947 | ||
4948 | if (ret == 0) { | |
4949 | if (rst_ctrl.bits.reset_ovfl_pmds) { | |
4950 | pfm_reset_regs(ctx, &ovfl_regs, PFM_PMD_LONG_RESET); | |
4951 | } | |
4952 | if (rst_ctrl.bits.mask_monitoring == 0) { | |
4953 | DPRINT(("resuming monitoring\n")); | |
4954 | if (ctx->ctx_state == PFM_CTX_MASKED) pfm_restore_monitoring(current); | |
4955 | } else { | |
4956 | DPRINT(("stopping monitoring\n")); | |
4957 | //pfm_stop_monitoring(current, regs); | |
4958 | } | |
4959 | ctx->ctx_state = PFM_CTX_LOADED; | |
4960 | } | |
4961 | } | |
4962 | ||
4963 | /* | |
4964 | * context MUST BE LOCKED when calling | |
4965 | * can only be called for current | |
4966 | */ | |
4967 | static void | |
4968 | pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs) | |
4969 | { | |
4970 | int ret; | |
4971 | ||
19c5870c | 4972 | DPRINT(("entering for [%d]\n", task_pid_nr(current))); |
1da177e4 LT |
4973 | |
4974 | ret = pfm_context_unload(ctx, NULL, 0, regs); | |
4975 | if (ret) { | |
19c5870c | 4976 | printk(KERN_ERR "pfm_context_force_terminate: [%d] unloaded failed with %d\n", task_pid_nr(current), ret); |
1da177e4 LT |
4977 | } |
4978 | ||
4979 | /* | |
4980 | * and wakeup controlling task, indicating we are now disconnected | |
4981 | */ | |
4982 | wake_up_interruptible(&ctx->ctx_zombieq); | |
4983 | ||
4984 | /* | |
4985 | * given that context is still locked, the controlling | |
4986 | * task will only get access when we return from | |
4987 | * pfm_handle_work(). | |
4988 | */ | |
4989 | } | |
4990 | ||
4991 | static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds); | |
0fb232fd | 4992 | |
4944930a SE |
4993 | /* |
4994 | * pfm_handle_work() can be called with interrupts enabled | |
4995 | * (TIF_NEED_RESCHED) or disabled. The down_interruptible | |
4996 | * call may sleep, therefore we must re-enable interrupts | |
4997 | * to avoid deadlocks. It is safe to do so because this function | |
0fb232fd | 4998 | * is called ONLY when returning to user level (pUStk=1), in which case |
4944930a SE |
4999 | * there is no risk of kernel stack overflow due to deep |
5000 | * interrupt nesting. | |
5001 | */ | |
1da177e4 LT |
5002 | void |
5003 | pfm_handle_work(void) | |
5004 | { | |
5005 | pfm_context_t *ctx; | |
5006 | struct pt_regs *regs; | |
4944930a | 5007 | unsigned long flags, dummy_flags; |
1da177e4 LT |
5008 | unsigned long ovfl_regs; |
5009 | unsigned int reason; | |
5010 | int ret; | |
5011 | ||
5012 | ctx = PFM_GET_CTX(current); | |
5013 | if (ctx == NULL) { | |
0fb232fd HS |
5014 | printk(KERN_ERR "perfmon: [%d] has no PFM context\n", |
5015 | task_pid_nr(current)); | |
1da177e4 LT |
5016 | return; |
5017 | } | |
5018 | ||
5019 | PROTECT_CTX(ctx, flags); | |
5020 | ||
5021 | PFM_SET_WORK_PENDING(current, 0); | |
5022 | ||
6450578f | 5023 | regs = task_pt_regs(current); |
1da177e4 LT |
5024 | |
5025 | /* | |
5026 | * extract reason for being here and clear | |
5027 | */ | |
5028 | reason = ctx->ctx_fl_trap_reason; | |
5029 | ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE; | |
5030 | ovfl_regs = ctx->ctx_ovfl_regs[0]; | |
5031 | ||
5032 | DPRINT(("reason=%d state=%d\n", reason, ctx->ctx_state)); | |
5033 | ||
5034 | /* | |
5035 | * must be done before we check for simple-reset mode | |
5036 | */ | |
0fb232fd HS |
5037 | if (ctx->ctx_fl_going_zombie || ctx->ctx_state == PFM_CTX_ZOMBIE) |
5038 | goto do_zombie; | |
1da177e4 LT |
5039 | |
5040 | //if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking; | |
0fb232fd HS |
5041 | if (reason == PFM_TRAP_REASON_RESET) |
5042 | goto skip_blocking; | |
1da177e4 | 5043 | |
4944930a SE |
5044 | /* |
5045 | * restore interrupt mask to what it was on entry. | |
5046 | * Could be enabled/diasbled. | |
5047 | */ | |
1da177e4 LT |
5048 | UNPROTECT_CTX(ctx, flags); |
5049 | ||
4944930a SE |
5050 | /* |
5051 | * force interrupt enable because of down_interruptible() | |
5052 | */ | |
1da177e4 LT |
5053 | local_irq_enable(); |
5054 | ||
5055 | DPRINT(("before block sleeping\n")); | |
5056 | ||
5057 | /* | |
5058 | * may go through without blocking on SMP systems | |
5059 | * if restart has been received already by the time we call down() | |
5060 | */ | |
60f1c444 | 5061 | ret = wait_for_completion_interruptible(&ctx->ctx_restart_done); |
1da177e4 LT |
5062 | |
5063 | DPRINT(("after block sleeping ret=%d\n", ret)); | |
5064 | ||
5065 | /* | |
4944930a SE |
5066 | * lock context and mask interrupts again |
5067 | * We save flags into a dummy because we may have | |
5068 | * altered interrupts mask compared to entry in this | |
5069 | * function. | |
1da177e4 | 5070 | */ |
4944930a | 5071 | PROTECT_CTX(ctx, dummy_flags); |
1da177e4 LT |
5072 | |
5073 | /* | |
5074 | * we need to read the ovfl_regs only after wake-up | |
5075 | * because we may have had pfm_write_pmds() in between | |
5076 | * and that can changed PMD values and therefore | |
5077 | * ovfl_regs is reset for these new PMD values. | |
5078 | */ | |
5079 | ovfl_regs = ctx->ctx_ovfl_regs[0]; | |
5080 | ||
5081 | if (ctx->ctx_fl_going_zombie) { | |
5082 | do_zombie: | |
5083 | DPRINT(("context is zombie, bailing out\n")); | |
5084 | pfm_context_force_terminate(ctx, regs); | |
5085 | goto nothing_to_do; | |
5086 | } | |
5087 | /* | |
5088 | * in case of interruption of down() we don't restart anything | |
5089 | */ | |
0fb232fd HS |
5090 | if (ret < 0) |
5091 | goto nothing_to_do; | |
1da177e4 LT |
5092 | |
5093 | skip_blocking: | |
5094 | pfm_resume_after_ovfl(ctx, ovfl_regs, regs); | |
5095 | ctx->ctx_ovfl_regs[0] = 0UL; | |
5096 | ||
5097 | nothing_to_do: | |
4944930a SE |
5098 | /* |
5099 | * restore flags as they were upon entry | |
5100 | */ | |
1da177e4 LT |
5101 | UNPROTECT_CTX(ctx, flags); |
5102 | } | |
5103 | ||
5104 | static int | |
5105 | pfm_notify_user(pfm_context_t *ctx, pfm_msg_t *msg) | |
5106 | { | |
5107 | if (ctx->ctx_state == PFM_CTX_ZOMBIE) { | |
5108 | DPRINT(("ignoring overflow notification, owner is zombie\n")); | |
5109 | return 0; | |
5110 | } | |
5111 | ||
5112 | DPRINT(("waking up somebody\n")); | |
5113 | ||
5114 | if (msg) wake_up_interruptible(&ctx->ctx_msgq_wait); | |
5115 | ||
5116 | /* | |
5117 | * safe, we are not in intr handler, nor in ctxsw when | |
5118 | * we come here | |
5119 | */ | |
5120 | kill_fasync (&ctx->ctx_async_queue, SIGIO, POLL_IN); | |
5121 | ||
5122 | return 0; | |
5123 | } | |
5124 | ||
5125 | static int | |
5126 | pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds) | |
5127 | { | |
5128 | pfm_msg_t *msg = NULL; | |
5129 | ||
5130 | if (ctx->ctx_fl_no_msg == 0) { | |
5131 | msg = pfm_get_new_msg(ctx); | |
5132 | if (msg == NULL) { | |
5133 | printk(KERN_ERR "perfmon: pfm_ovfl_notify_user no more notification msgs\n"); | |
5134 | return -1; | |
5135 | } | |
5136 | ||
5137 | msg->pfm_ovfl_msg.msg_type = PFM_MSG_OVFL; | |
5138 | msg->pfm_ovfl_msg.msg_ctx_fd = ctx->ctx_fd; | |
5139 | msg->pfm_ovfl_msg.msg_active_set = 0; | |
5140 | msg->pfm_ovfl_msg.msg_ovfl_pmds[0] = ovfl_pmds; | |
5141 | msg->pfm_ovfl_msg.msg_ovfl_pmds[1] = 0UL; | |
5142 | msg->pfm_ovfl_msg.msg_ovfl_pmds[2] = 0UL; | |
5143 | msg->pfm_ovfl_msg.msg_ovfl_pmds[3] = 0UL; | |
5144 | msg->pfm_ovfl_msg.msg_tstamp = 0UL; | |
5145 | } | |
5146 | ||
5147 | DPRINT(("ovfl msg: msg=%p no_msg=%d fd=%d ovfl_pmds=0x%lx\n", | |
5148 | msg, | |
5149 | ctx->ctx_fl_no_msg, | |
5150 | ctx->ctx_fd, | |
5151 | ovfl_pmds)); | |
5152 | ||
5153 | return pfm_notify_user(ctx, msg); | |
5154 | } | |
5155 | ||
5156 | static int | |
5157 | pfm_end_notify_user(pfm_context_t *ctx) | |
5158 | { | |
5159 | pfm_msg_t *msg; | |
5160 | ||
5161 | msg = pfm_get_new_msg(ctx); | |
5162 | if (msg == NULL) { | |
5163 | printk(KERN_ERR "perfmon: pfm_end_notify_user no more notification msgs\n"); | |
5164 | return -1; | |
5165 | } | |
5166 | /* no leak */ | |
5167 | memset(msg, 0, sizeof(*msg)); | |
5168 | ||
5169 | msg->pfm_end_msg.msg_type = PFM_MSG_END; | |
5170 | msg->pfm_end_msg.msg_ctx_fd = ctx->ctx_fd; | |
5171 | msg->pfm_ovfl_msg.msg_tstamp = 0UL; | |
5172 | ||
5173 | DPRINT(("end msg: msg=%p no_msg=%d ctx_fd=%d\n", | |
5174 | msg, | |
5175 | ctx->ctx_fl_no_msg, | |
5176 | ctx->ctx_fd)); | |
5177 | ||
5178 | return pfm_notify_user(ctx, msg); | |
5179 | } | |
5180 | ||
5181 | /* | |
5182 | * main overflow processing routine. | |
72fdbdce | 5183 | * it can be called from the interrupt path or explicitly during the context switch code |
1da177e4 | 5184 | */ |
e088a4ad MW |
5185 | static void pfm_overflow_handler(struct task_struct *task, pfm_context_t *ctx, |
5186 | unsigned long pmc0, struct pt_regs *regs) | |
1da177e4 LT |
5187 | { |
5188 | pfm_ovfl_arg_t *ovfl_arg; | |
5189 | unsigned long mask; | |
5190 | unsigned long old_val, ovfl_val, new_val; | |
5191 | unsigned long ovfl_notify = 0UL, ovfl_pmds = 0UL, smpl_pmds = 0UL, reset_pmds; | |
5192 | unsigned long tstamp; | |
5193 | pfm_ovfl_ctrl_t ovfl_ctrl; | |
5194 | unsigned int i, has_smpl; | |
5195 | int must_notify = 0; | |
5196 | ||
5197 | if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) goto stop_monitoring; | |
5198 | ||
5199 | /* | |
5200 | * sanity test. Should never happen | |
5201 | */ | |
5202 | if (unlikely((pmc0 & 0x1) == 0)) goto sanity_check; | |
5203 | ||
5204 | tstamp = ia64_get_itc(); | |
5205 | mask = pmc0 >> PMU_FIRST_COUNTER; | |
5206 | ovfl_val = pmu_conf->ovfl_val; | |
5207 | has_smpl = CTX_HAS_SMPL(ctx); | |
5208 | ||
5209 | DPRINT_ovfl(("pmc0=0x%lx pid=%d iip=0x%lx, %s " | |
5210 | "used_pmds=0x%lx\n", | |
5211 | pmc0, | |
19c5870c | 5212 | task ? task_pid_nr(task): -1, |
1da177e4 LT |
5213 | (regs ? regs->cr_iip : 0), |
5214 | CTX_OVFL_NOBLOCK(ctx) ? "nonblocking" : "blocking", | |
5215 | ctx->ctx_used_pmds[0])); | |
5216 | ||
5217 | ||
5218 | /* | |
5219 | * first we update the virtual counters | |
5220 | * assume there was a prior ia64_srlz_d() issued | |
5221 | */ | |
5222 | for (i = PMU_FIRST_COUNTER; mask ; i++, mask >>= 1) { | |
5223 | ||
5224 | /* skip pmd which did not overflow */ | |
5225 | if ((mask & 0x1) == 0) continue; | |
5226 | ||
5227 | /* | |
5228 | * Note that the pmd is not necessarily 0 at this point as qualified events | |
5229 | * may have happened before the PMU was frozen. The residual count is not | |
5230 | * taken into consideration here but will be with any read of the pmd via | |
5231 | * pfm_read_pmds(). | |
5232 | */ | |
5233 | old_val = new_val = ctx->ctx_pmds[i].val; | |
5234 | new_val += 1 + ovfl_val; | |
5235 | ctx->ctx_pmds[i].val = new_val; | |
5236 | ||
5237 | /* | |
5238 | * check for overflow condition | |
5239 | */ | |
5240 | if (likely(old_val > new_val)) { | |
5241 | ovfl_pmds |= 1UL << i; | |
5242 | if (PMC_OVFL_NOTIFY(ctx, i)) ovfl_notify |= 1UL << i; | |
5243 | } | |
5244 | ||
5245 | DPRINT_ovfl(("ctx_pmd[%d].val=0x%lx old_val=0x%lx pmd=0x%lx ovfl_pmds=0x%lx ovfl_notify=0x%lx\n", | |
5246 | i, | |
5247 | new_val, | |
5248 | old_val, | |
5249 | ia64_get_pmd(i) & ovfl_val, | |
5250 | ovfl_pmds, | |
5251 | ovfl_notify)); | |
5252 | } | |
5253 | ||
5254 | /* | |
5255 | * there was no 64-bit overflow, nothing else to do | |
5256 | */ | |
5257 | if (ovfl_pmds == 0UL) return; | |
5258 | ||
5259 | /* | |
5260 | * reset all control bits | |
5261 | */ | |
5262 | ovfl_ctrl.val = 0; | |
5263 | reset_pmds = 0UL; | |
5264 | ||
5265 | /* | |
5266 | * if a sampling format module exists, then we "cache" the overflow by | |
5267 | * calling the module's handler() routine. | |
5268 | */ | |
5269 | if (has_smpl) { | |
5270 | unsigned long start_cycles, end_cycles; | |
5271 | unsigned long pmd_mask; | |
5272 | int j, k, ret = 0; | |
5273 | int this_cpu = smp_processor_id(); | |
5274 | ||
5275 | pmd_mask = ovfl_pmds >> PMU_FIRST_COUNTER; | |
5276 | ovfl_arg = &ctx->ctx_ovfl_arg; | |
5277 | ||
5278 | prefetch(ctx->ctx_smpl_hdr); | |
5279 | ||
5280 | for(i=PMU_FIRST_COUNTER; pmd_mask && ret == 0; i++, pmd_mask >>=1) { | |
5281 | ||
5282 | mask = 1UL << i; | |
5283 | ||
5284 | if ((pmd_mask & 0x1) == 0) continue; | |
5285 | ||
5286 | ovfl_arg->ovfl_pmd = (unsigned char )i; | |
5287 | ovfl_arg->ovfl_notify = ovfl_notify & mask ? 1 : 0; | |
5288 | ovfl_arg->active_set = 0; | |
5289 | ovfl_arg->ovfl_ctrl.val = 0; /* module must fill in all fields */ | |
5290 | ovfl_arg->smpl_pmds[0] = smpl_pmds = ctx->ctx_pmds[i].smpl_pmds[0]; | |
5291 | ||
5292 | ovfl_arg->pmd_value = ctx->ctx_pmds[i].val; | |
5293 | ovfl_arg->pmd_last_reset = ctx->ctx_pmds[i].lval; | |
5294 | ovfl_arg->pmd_eventid = ctx->ctx_pmds[i].eventid; | |
5295 | ||
5296 | /* | |
5297 | * copy values of pmds of interest. Sampling format may copy them | |
5298 | * into sampling buffer. | |
5299 | */ | |
5300 | if (smpl_pmds) { | |
5301 | for(j=0, k=0; smpl_pmds; j++, smpl_pmds >>=1) { | |
5302 | if ((smpl_pmds & 0x1) == 0) continue; | |
5303 | ovfl_arg->smpl_pmds_values[k++] = PMD_IS_COUNTING(j) ? pfm_read_soft_counter(ctx, j) : ia64_get_pmd(j); | |
5304 | DPRINT_ovfl(("smpl_pmd[%d]=pmd%u=0x%lx\n", k-1, j, ovfl_arg->smpl_pmds_values[k-1])); | |
5305 | } | |
5306 | } | |
5307 | ||
5308 | pfm_stats[this_cpu].pfm_smpl_handler_calls++; | |
5309 | ||
5310 | start_cycles = ia64_get_itc(); | |
5311 | ||
5312 | /* | |
5313 | * call custom buffer format record (handler) routine | |
5314 | */ | |
5315 | ret = (*ctx->ctx_buf_fmt->fmt_handler)(task, ctx->ctx_smpl_hdr, ovfl_arg, regs, tstamp); | |
5316 | ||
5317 | end_cycles = ia64_get_itc(); | |
5318 | ||
5319 | /* | |
5320 | * For those controls, we take the union because they have | |
5321 | * an all or nothing behavior. | |
5322 | */ | |
5323 | ovfl_ctrl.bits.notify_user |= ovfl_arg->ovfl_ctrl.bits.notify_user; | |
5324 | ovfl_ctrl.bits.block_task |= ovfl_arg->ovfl_ctrl.bits.block_task; | |
5325 | ovfl_ctrl.bits.mask_monitoring |= ovfl_arg->ovfl_ctrl.bits.mask_monitoring; | |
5326 | /* | |
5327 | * build the bitmask of pmds to reset now | |
5328 | */ | |
5329 | if (ovfl_arg->ovfl_ctrl.bits.reset_ovfl_pmds) reset_pmds |= mask; | |
5330 | ||
5331 | pfm_stats[this_cpu].pfm_smpl_handler_cycles += end_cycles - start_cycles; | |
5332 | } | |
5333 | /* | |
5334 | * when the module cannot handle the rest of the overflows, we abort right here | |
5335 | */ | |
5336 | if (ret && pmd_mask) { | |
5337 | DPRINT(("handler aborts leftover ovfl_pmds=0x%lx\n", | |
5338 | pmd_mask<<PMU_FIRST_COUNTER)); | |
5339 | } | |
5340 | /* | |
5341 | * remove the pmds we reset now from the set of pmds to reset in pfm_restart() | |
5342 | */ | |
5343 | ovfl_pmds &= ~reset_pmds; | |
5344 | } else { | |
5345 | /* | |
5346 | * when no sampling module is used, then the default | |
5347 | * is to notify on overflow if requested by user | |
5348 | */ | |
5349 | ovfl_ctrl.bits.notify_user = ovfl_notify ? 1 : 0; | |
5350 | ovfl_ctrl.bits.block_task = ovfl_notify ? 1 : 0; | |
5351 | ovfl_ctrl.bits.mask_monitoring = ovfl_notify ? 1 : 0; /* XXX: change for saturation */ | |
5352 | ovfl_ctrl.bits.reset_ovfl_pmds = ovfl_notify ? 0 : 1; | |
5353 | /* | |
5354 | * if needed, we reset all overflowed pmds | |
5355 | */ | |
5356 | if (ovfl_notify == 0) reset_pmds = ovfl_pmds; | |
5357 | } | |
5358 | ||
5359 | DPRINT_ovfl(("ovfl_pmds=0x%lx reset_pmds=0x%lx\n", ovfl_pmds, reset_pmds)); | |
5360 | ||
5361 | /* | |
5362 | * reset the requested PMD registers using the short reset values | |
5363 | */ | |
5364 | if (reset_pmds) { | |
5365 | unsigned long bm = reset_pmds; | |
5366 | pfm_reset_regs(ctx, &bm, PFM_PMD_SHORT_RESET); | |
5367 | } | |
5368 | ||
5369 | if (ovfl_notify && ovfl_ctrl.bits.notify_user) { | |
5370 | /* | |
5371 | * keep track of what to reset when unblocking | |
5372 | */ | |
5373 | ctx->ctx_ovfl_regs[0] = ovfl_pmds; | |
5374 | ||
5375 | /* | |
5376 | * check for blocking context | |
5377 | */ | |
5378 | if (CTX_OVFL_NOBLOCK(ctx) == 0 && ovfl_ctrl.bits.block_task) { | |
5379 | ||
5380 | ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_BLOCK; | |
5381 | ||
5382 | /* | |
5383 | * set the perfmon specific checking pending work for the task | |
5384 | */ | |
5385 | PFM_SET_WORK_PENDING(task, 1); | |
5386 | ||
5387 | /* | |
5388 | * when coming from ctxsw, current still points to the | |
5389 | * previous task, therefore we must work with task and not current. | |
5390 | */ | |
f14488cc | 5391 | set_notify_resume(task); |
1da177e4 LT |
5392 | } |
5393 | /* | |
5394 | * defer until state is changed (shorten spin window). the context is locked | |
5395 | * anyway, so the signal receiver would come spin for nothing. | |
5396 | */ | |
5397 | must_notify = 1; | |
5398 | } | |
5399 | ||
5400 | DPRINT_ovfl(("owner [%d] pending=%ld reason=%u ovfl_pmds=0x%lx ovfl_notify=0x%lx masked=%d\n", | |
19c5870c | 5401 | GET_PMU_OWNER() ? task_pid_nr(GET_PMU_OWNER()) : -1, |
1da177e4 LT |
5402 | PFM_GET_WORK_PENDING(task), |
5403 | ctx->ctx_fl_trap_reason, | |
5404 | ovfl_pmds, | |
5405 | ovfl_notify, | |
5406 | ovfl_ctrl.bits.mask_monitoring ? 1 : 0)); | |
5407 | /* | |
5408 | * in case monitoring must be stopped, we toggle the psr bits | |
5409 | */ | |
5410 | if (ovfl_ctrl.bits.mask_monitoring) { | |
5411 | pfm_mask_monitoring(task); | |
5412 | ctx->ctx_state = PFM_CTX_MASKED; | |
5413 | ctx->ctx_fl_can_restart = 1; | |
5414 | } | |
5415 | ||
5416 | /* | |
5417 | * send notification now | |
5418 | */ | |
5419 | if (must_notify) pfm_ovfl_notify_user(ctx, ovfl_notify); | |
5420 | ||
5421 | return; | |
5422 | ||
5423 | sanity_check: | |
5424 | printk(KERN_ERR "perfmon: CPU%d overflow handler [%d] pmc0=0x%lx\n", | |
5425 | smp_processor_id(), | |
19c5870c | 5426 | task ? task_pid_nr(task) : -1, |
1da177e4 LT |
5427 | pmc0); |
5428 | return; | |
5429 | ||
5430 | stop_monitoring: | |
5431 | /* | |
5432 | * in SMP, zombie context is never restored but reclaimed in pfm_load_regs(). | |
5433 | * Moreover, zombies are also reclaimed in pfm_save_regs(). Therefore we can | |
5434 | * come here as zombie only if the task is the current task. In which case, we | |
5435 | * can access the PMU hardware directly. | |
5436 | * | |
5437 | * Note that zombies do have PM_VALID set. So here we do the minimal. | |
5438 | * | |
5439 | * In case the context was zombified it could not be reclaimed at the time | |
5440 | * the monitoring program exited. At this point, the PMU reservation has been | |
5441 | * returned, the sampiing buffer has been freed. We must convert this call | |
5442 | * into a spurious interrupt. However, we must also avoid infinite overflows | |
5443 | * by stopping monitoring for this task. We can only come here for a per-task | |
5444 | * context. All we need to do is to stop monitoring using the psr bits which | |
5445 | * are always task private. By re-enabling secure montioring, we ensure that | |
5446 | * the monitored task will not be able to re-activate monitoring. | |
5447 | * The task will eventually be context switched out, at which point the context | |
5448 | * will be reclaimed (that includes releasing ownership of the PMU). | |
5449 | * | |
5450 | * So there might be a window of time where the number of per-task session is zero | |
5451 | * yet one PMU might have a owner and get at most one overflow interrupt for a zombie | |
5452 | * context. This is safe because if a per-task session comes in, it will push this one | |
5453 | * out and by the virtue on pfm_save_regs(), this one will disappear. If a system wide | |
5454 | * session is force on that CPU, given that we use task pinning, pfm_save_regs() will | |
5455 | * also push our zombie context out. | |
5456 | * | |
5457 | * Overall pretty hairy stuff.... | |
5458 | */ | |
19c5870c | 5459 | DPRINT(("ctx is zombie for [%d], converted to spurious\n", task ? task_pid_nr(task): -1)); |
1da177e4 LT |
5460 | pfm_clear_psr_up(); |
5461 | ia64_psr(regs)->up = 0; | |
5462 | ia64_psr(regs)->sp = 1; | |
5463 | return; | |
5464 | } | |
5465 | ||
5466 | static int | |
9010eff0 | 5467 | pfm_do_interrupt_handler(void *arg, struct pt_regs *regs) |
1da177e4 LT |
5468 | { |
5469 | struct task_struct *task; | |
5470 | pfm_context_t *ctx; | |
5471 | unsigned long flags; | |
5472 | u64 pmc0; | |
5473 | int this_cpu = smp_processor_id(); | |
5474 | int retval = 0; | |
5475 | ||
5476 | pfm_stats[this_cpu].pfm_ovfl_intr_count++; | |
5477 | ||
5478 | /* | |
5479 | * srlz.d done before arriving here | |
5480 | */ | |
5481 | pmc0 = ia64_get_pmc(0); | |
5482 | ||
5483 | task = GET_PMU_OWNER(); | |
5484 | ctx = GET_PMU_CTX(); | |
5485 | ||
5486 | /* | |
5487 | * if we have some pending bits set | |
5488 | * assumes : if any PMC0.bit[63-1] is set, then PMC0.fr = 1 | |
5489 | */ | |
5490 | if (PMC0_HAS_OVFL(pmc0) && task) { | |
5491 | /* | |
5492 | * we assume that pmc0.fr is always set here | |
5493 | */ | |
5494 | ||
5495 | /* sanity check */ | |
5496 | if (!ctx) goto report_spurious1; | |
5497 | ||
5498 | if (ctx->ctx_fl_system == 0 && (task->thread.flags & IA64_THREAD_PM_VALID) == 0) | |
5499 | goto report_spurious2; | |
5500 | ||
5501 | PROTECT_CTX_NOPRINT(ctx, flags); | |
5502 | ||
5503 | pfm_overflow_handler(task, ctx, pmc0, regs); | |
5504 | ||
5505 | UNPROTECT_CTX_NOPRINT(ctx, flags); | |
5506 | ||
5507 | } else { | |
5508 | pfm_stats[this_cpu].pfm_spurious_ovfl_intr_count++; | |
5509 | retval = -1; | |
5510 | } | |
5511 | /* | |
5512 | * keep it unfrozen at all times | |
5513 | */ | |
5514 | pfm_unfreeze_pmu(); | |
5515 | ||
5516 | return retval; | |
5517 | ||
5518 | report_spurious1: | |
5519 | printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d has no PFM context\n", | |
19c5870c | 5520 | this_cpu, task_pid_nr(task)); |
1da177e4 LT |
5521 | pfm_unfreeze_pmu(); |
5522 | return -1; | |
5523 | report_spurious2: | |
5524 | printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d, invalid flag\n", | |
5525 | this_cpu, | |
19c5870c | 5526 | task_pid_nr(task)); |
1da177e4 LT |
5527 | pfm_unfreeze_pmu(); |
5528 | return -1; | |
5529 | } | |
5530 | ||
5531 | static irqreturn_t | |
3bbe486b | 5532 | pfm_interrupt_handler(int irq, void *arg) |
1da177e4 LT |
5533 | { |
5534 | unsigned long start_cycles, total_cycles; | |
5535 | unsigned long min, max; | |
5536 | int this_cpu; | |
5537 | int ret; | |
3bbe486b | 5538 | struct pt_regs *regs = get_irq_regs(); |
1da177e4 LT |
5539 | |
5540 | this_cpu = get_cpu(); | |
a1ecf7f6 TL |
5541 | if (likely(!pfm_alt_intr_handler)) { |
5542 | min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min; | |
5543 | max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max; | |
1da177e4 | 5544 | |
a1ecf7f6 | 5545 | start_cycles = ia64_get_itc(); |
1da177e4 | 5546 | |
9010eff0 | 5547 | ret = pfm_do_interrupt_handler(arg, regs); |
1da177e4 | 5548 | |
a1ecf7f6 | 5549 | total_cycles = ia64_get_itc(); |
1da177e4 | 5550 | |
a1ecf7f6 TL |
5551 | /* |
5552 | * don't measure spurious interrupts | |
5553 | */ | |
5554 | if (likely(ret == 0)) { | |
5555 | total_cycles -= start_cycles; | |
1da177e4 | 5556 | |
a1ecf7f6 TL |
5557 | if (total_cycles < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = total_cycles; |
5558 | if (total_cycles > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = total_cycles; | |
1da177e4 | 5559 | |
a1ecf7f6 TL |
5560 | pfm_stats[this_cpu].pfm_ovfl_intr_cycles += total_cycles; |
5561 | } | |
5562 | } | |
5563 | else { | |
5564 | (*pfm_alt_intr_handler->handler)(irq, arg, regs); | |
1da177e4 | 5565 | } |
a1ecf7f6 | 5566 | |
8b0b1db0 | 5567 | put_cpu(); |
1da177e4 LT |
5568 | return IRQ_HANDLED; |
5569 | } | |
5570 | ||
5571 | /* | |
5572 | * /proc/perfmon interface, for debug only | |
5573 | */ | |
5574 | ||
fa276f36 | 5575 | #define PFM_PROC_SHOW_HEADER ((void *)(long)nr_cpu_ids+1) |
1da177e4 LT |
5576 | |
5577 | static void * | |
5578 | pfm_proc_start(struct seq_file *m, loff_t *pos) | |
5579 | { | |
5580 | if (*pos == 0) { | |
5581 | return PFM_PROC_SHOW_HEADER; | |
5582 | } | |
5583 | ||
5dd3c994 | 5584 | while (*pos <= nr_cpu_ids) { |
1da177e4 LT |
5585 | if (cpu_online(*pos - 1)) { |
5586 | return (void *)*pos; | |
5587 | } | |
5588 | ++*pos; | |
5589 | } | |
5590 | return NULL; | |
5591 | } | |
5592 | ||
5593 | static void * | |
5594 | pfm_proc_next(struct seq_file *m, void *v, loff_t *pos) | |
5595 | { | |
5596 | ++*pos; | |
5597 | return pfm_proc_start(m, pos); | |
5598 | } | |
5599 | ||
5600 | static void | |
5601 | pfm_proc_stop(struct seq_file *m, void *v) | |
5602 | { | |
5603 | } | |
5604 | ||
5605 | static void | |
5606 | pfm_proc_show_header(struct seq_file *m) | |
5607 | { | |
5608 | struct list_head * pos; | |
5609 | pfm_buffer_fmt_t * entry; | |
5610 | unsigned long flags; | |
5611 | ||
5612 | seq_printf(m, | |
5613 | "perfmon version : %u.%u\n" | |
5614 | "model : %s\n" | |
5615 | "fastctxsw : %s\n" | |
5616 | "expert mode : %s\n" | |
5617 | "ovfl_mask : 0x%lx\n" | |
5618 | "PMU flags : 0x%x\n", | |
5619 | PFM_VERSION_MAJ, PFM_VERSION_MIN, | |
5620 | pmu_conf->pmu_name, | |
5621 | pfm_sysctl.fastctxsw > 0 ? "Yes": "No", | |
5622 | pfm_sysctl.expert_mode > 0 ? "Yes": "No", | |
5623 | pmu_conf->ovfl_val, | |
5624 | pmu_conf->flags); | |
5625 | ||
5626 | LOCK_PFS(flags); | |
5627 | ||
5628 | seq_printf(m, | |
5629 | "proc_sessions : %u\n" | |
5630 | "sys_sessions : %u\n" | |
5631 | "sys_use_dbregs : %u\n" | |
5632 | "ptrace_use_dbregs : %u\n", | |
5633 | pfm_sessions.pfs_task_sessions, | |
5634 | pfm_sessions.pfs_sys_sessions, | |
5635 | pfm_sessions.pfs_sys_use_dbregs, | |
5636 | pfm_sessions.pfs_ptrace_use_dbregs); | |
5637 | ||
5638 | UNLOCK_PFS(flags); | |
5639 | ||
5640 | spin_lock(&pfm_buffer_fmt_lock); | |
5641 | ||
5642 | list_for_each(pos, &pfm_buffer_fmt_list) { | |
5643 | entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list); | |
7451adc5 AS |
5644 | seq_printf(m, "format : %16phD %s\n", |
5645 | entry->fmt_uuid, entry->fmt_name); | |
1da177e4 LT |
5646 | } |
5647 | spin_unlock(&pfm_buffer_fmt_lock); | |
5648 | ||
5649 | } | |
5650 | ||
5651 | static int | |
5652 | pfm_proc_show(struct seq_file *m, void *v) | |
5653 | { | |
5654 | unsigned long psr; | |
5655 | unsigned int i; | |
5656 | int cpu; | |
5657 | ||
5658 | if (v == PFM_PROC_SHOW_HEADER) { | |
5659 | pfm_proc_show_header(m); | |
5660 | return 0; | |
5661 | } | |
5662 | ||
5663 | /* show info for CPU (v - 1) */ | |
5664 | ||
5665 | cpu = (long)v - 1; | |
5666 | seq_printf(m, | |
5667 | "CPU%-2d overflow intrs : %lu\n" | |
5668 | "CPU%-2d overflow cycles : %lu\n" | |
5669 | "CPU%-2d overflow min : %lu\n" | |
5670 | "CPU%-2d overflow max : %lu\n" | |
5671 | "CPU%-2d smpl handler calls : %lu\n" | |
5672 | "CPU%-2d smpl handler cycles : %lu\n" | |
5673 | "CPU%-2d spurious intrs : %lu\n" | |
5674 | "CPU%-2d replay intrs : %lu\n" | |
5675 | "CPU%-2d syst_wide : %d\n" | |
5676 | "CPU%-2d dcr_pp : %d\n" | |
5677 | "CPU%-2d exclude idle : %d\n" | |
5678 | "CPU%-2d owner : %d\n" | |
5679 | "CPU%-2d context : %p\n" | |
5680 | "CPU%-2d activations : %lu\n", | |
5681 | cpu, pfm_stats[cpu].pfm_ovfl_intr_count, | |
5682 | cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles, | |
5683 | cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_min, | |
5684 | cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_max, | |
5685 | cpu, pfm_stats[cpu].pfm_smpl_handler_calls, | |
5686 | cpu, pfm_stats[cpu].pfm_smpl_handler_cycles, | |
5687 | cpu, pfm_stats[cpu].pfm_spurious_ovfl_intr_count, | |
5688 | cpu, pfm_stats[cpu].pfm_replay_ovfl_intr_count, | |
5689 | cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_SYST_WIDE ? 1 : 0, | |
5690 | cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_DCR_PP ? 1 : 0, | |
5691 | cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_EXCL_IDLE ? 1 : 0, | |
5692 | cpu, pfm_get_cpu_data(pmu_owner, cpu) ? pfm_get_cpu_data(pmu_owner, cpu)->pid: -1, | |
5693 | cpu, pfm_get_cpu_data(pmu_ctx, cpu), | |
5694 | cpu, pfm_get_cpu_data(pmu_activation_number, cpu)); | |
5695 | ||
5696 | if (num_online_cpus() == 1 && pfm_sysctl.debug > 0) { | |
5697 | ||
5698 | psr = pfm_get_psr(); | |
5699 | ||
5700 | ia64_srlz_d(); | |
5701 | ||
5702 | seq_printf(m, | |
5703 | "CPU%-2d psr : 0x%lx\n" | |
5704 | "CPU%-2d pmc0 : 0x%lx\n", | |
5705 | cpu, psr, | |
5706 | cpu, ia64_get_pmc(0)); | |
5707 | ||
5708 | for (i=0; PMC_IS_LAST(i) == 0; i++) { | |
5709 | if (PMC_IS_COUNTING(i) == 0) continue; | |
5710 | seq_printf(m, | |
5711 | "CPU%-2d pmc%u : 0x%lx\n" | |
5712 | "CPU%-2d pmd%u : 0x%lx\n", | |
5713 | cpu, i, ia64_get_pmc(i), | |
5714 | cpu, i, ia64_get_pmd(i)); | |
5715 | } | |
5716 | } | |
5717 | return 0; | |
5718 | } | |
5719 | ||
a23fe55e | 5720 | const struct seq_operations pfm_seq_ops = { |
1da177e4 LT |
5721 | .start = pfm_proc_start, |
5722 | .next = pfm_proc_next, | |
5723 | .stop = pfm_proc_stop, | |
5724 | .show = pfm_proc_show | |
5725 | }; | |
5726 | ||
5727 | static int | |
5728 | pfm_proc_open(struct inode *inode, struct file *file) | |
5729 | { | |
5730 | return seq_open(file, &pfm_seq_ops); | |
5731 | } | |
5732 | ||
5733 | ||
5734 | /* | |
5735 | * we come here as soon as local_cpu_data->pfm_syst_wide is set. this happens | |
5736 | * during pfm_enable() hence before pfm_start(). We cannot assume monitoring | |
5737 | * is active or inactive based on mode. We must rely on the value in | |
5738 | * local_cpu_data->pfm_syst_info | |
5739 | */ | |
5740 | void | |
5741 | pfm_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin) | |
5742 | { | |
5743 | struct pt_regs *regs; | |
5744 | unsigned long dcr; | |
5745 | unsigned long dcr_pp; | |
5746 | ||
5747 | dcr_pp = info & PFM_CPUINFO_DCR_PP ? 1 : 0; | |
5748 | ||
5749 | /* | |
5750 | * pid 0 is guaranteed to be the idle task. There is one such task with pid 0 | |
5751 | * on every CPU, so we can rely on the pid to identify the idle task. | |
5752 | */ | |
5753 | if ((info & PFM_CPUINFO_EXCL_IDLE) == 0 || task->pid) { | |
6450578f | 5754 | regs = task_pt_regs(task); |
1da177e4 LT |
5755 | ia64_psr(regs)->pp = is_ctxswin ? dcr_pp : 0; |
5756 | return; | |
5757 | } | |
5758 | /* | |
5759 | * if monitoring has started | |
5760 | */ | |
5761 | if (dcr_pp) { | |
5762 | dcr = ia64_getreg(_IA64_REG_CR_DCR); | |
5763 | /* | |
5764 | * context switching in? | |
5765 | */ | |
5766 | if (is_ctxswin) { | |
5767 | /* mask monitoring for the idle task */ | |
5768 | ia64_setreg(_IA64_REG_CR_DCR, dcr & ~IA64_DCR_PP); | |
5769 | pfm_clear_psr_pp(); | |
5770 | ia64_srlz_i(); | |
5771 | return; | |
5772 | } | |
5773 | /* | |
5774 | * context switching out | |
5775 | * restore monitoring for next task | |
5776 | * | |
5777 | * Due to inlining this odd if-then-else construction generates | |
5778 | * better code. | |
5779 | */ | |
5780 | ia64_setreg(_IA64_REG_CR_DCR, dcr |IA64_DCR_PP); | |
5781 | pfm_set_psr_pp(); | |
5782 | ia64_srlz_i(); | |
5783 | } | |
5784 | } | |
5785 | ||
5786 | #ifdef CONFIG_SMP | |
5787 | ||
5788 | static void | |
5789 | pfm_force_cleanup(pfm_context_t *ctx, struct pt_regs *regs) | |
5790 | { | |
5791 | struct task_struct *task = ctx->ctx_task; | |
5792 | ||
5793 | ia64_psr(regs)->up = 0; | |
5794 | ia64_psr(regs)->sp = 1; | |
5795 | ||
5796 | if (GET_PMU_OWNER() == task) { | |
19c5870c AD |
5797 | DPRINT(("cleared ownership for [%d]\n", |
5798 | task_pid_nr(ctx->ctx_task))); | |
1da177e4 LT |
5799 | SET_PMU_OWNER(NULL, NULL); |
5800 | } | |
5801 | ||
5802 | /* | |
5803 | * disconnect the task from the context and vice-versa | |
5804 | */ | |
5805 | PFM_SET_WORK_PENDING(task, 0); | |
5806 | ||
5807 | task->thread.pfm_context = NULL; | |
5808 | task->thread.flags &= ~IA64_THREAD_PM_VALID; | |
5809 | ||
19c5870c | 5810 | DPRINT(("force cleanup for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
5811 | } |
5812 | ||
5813 | ||
5814 | /* | |
5815 | * in 2.6, interrupts are masked when we come here and the runqueue lock is held | |
5816 | */ | |
5817 | void | |
5818 | pfm_save_regs(struct task_struct *task) | |
5819 | { | |
5820 | pfm_context_t *ctx; | |
1da177e4 LT |
5821 | unsigned long flags; |
5822 | u64 psr; | |
5823 | ||
5824 | ||
5825 | ctx = PFM_GET_CTX(task); | |
5826 | if (ctx == NULL) return; | |
1da177e4 LT |
5827 | |
5828 | /* | |
5829 | * we always come here with interrupts ALREADY disabled by | |
5830 | * the scheduler. So we simply need to protect against concurrent | |
5831 | * access, not CPU concurrency. | |
5832 | */ | |
5833 | flags = pfm_protect_ctx_ctxsw(ctx); | |
5834 | ||
5835 | if (ctx->ctx_state == PFM_CTX_ZOMBIE) { | |
6450578f | 5836 | struct pt_regs *regs = task_pt_regs(task); |
1da177e4 LT |
5837 | |
5838 | pfm_clear_psr_up(); | |
5839 | ||
5840 | pfm_force_cleanup(ctx, regs); | |
5841 | ||
5842 | BUG_ON(ctx->ctx_smpl_hdr); | |
5843 | ||
5844 | pfm_unprotect_ctx_ctxsw(ctx, flags); | |
5845 | ||
5846 | pfm_context_free(ctx); | |
5847 | return; | |
5848 | } | |
5849 | ||
5850 | /* | |
5851 | * save current PSR: needed because we modify it | |
5852 | */ | |
5853 | ia64_srlz_d(); | |
5854 | psr = pfm_get_psr(); | |
5855 | ||
5856 | BUG_ON(psr & (IA64_PSR_I)); | |
5857 | ||
5858 | /* | |
5859 | * stop monitoring: | |
5860 | * This is the last instruction which may generate an overflow | |
5861 | * | |
5862 | * We do not need to set psr.sp because, it is irrelevant in kernel. | |
5863 | * It will be restored from ipsr when going back to user level | |
5864 | */ | |
5865 | pfm_clear_psr_up(); | |
5866 | ||
5867 | /* | |
5868 | * keep a copy of psr.up (for reload) | |
5869 | */ | |
5870 | ctx->ctx_saved_psr_up = psr & IA64_PSR_UP; | |
5871 | ||
5872 | /* | |
5873 | * release ownership of this PMU. | |
5874 | * PM interrupts are masked, so nothing | |
5875 | * can happen. | |
5876 | */ | |
5877 | SET_PMU_OWNER(NULL, NULL); | |
5878 | ||
5879 | /* | |
5880 | * we systematically save the PMD as we have no | |
5881 | * guarantee we will be schedule at that same | |
5882 | * CPU again. | |
5883 | */ | |
35589a8f | 5884 | pfm_save_pmds(ctx->th_pmds, ctx->ctx_used_pmds[0]); |
1da177e4 LT |
5885 | |
5886 | /* | |
5887 | * save pmc0 ia64_srlz_d() done in pfm_save_pmds() | |
5888 | * we will need it on the restore path to check | |
5889 | * for pending overflow. | |
5890 | */ | |
35589a8f | 5891 | ctx->th_pmcs[0] = ia64_get_pmc(0); |
1da177e4 LT |
5892 | |
5893 | /* | |
5894 | * unfreeze PMU if had pending overflows | |
5895 | */ | |
35589a8f | 5896 | if (ctx->th_pmcs[0] & ~0x1UL) pfm_unfreeze_pmu(); |
1da177e4 LT |
5897 | |
5898 | /* | |
5899 | * finally, allow context access. | |
5900 | * interrupts will still be masked after this call. | |
5901 | */ | |
5902 | pfm_unprotect_ctx_ctxsw(ctx, flags); | |
5903 | } | |
5904 | ||
5905 | #else /* !CONFIG_SMP */ | |
5906 | void | |
5907 | pfm_save_regs(struct task_struct *task) | |
5908 | { | |
5909 | pfm_context_t *ctx; | |
5910 | u64 psr; | |
5911 | ||
5912 | ctx = PFM_GET_CTX(task); | |
5913 | if (ctx == NULL) return; | |
5914 | ||
5915 | /* | |
5916 | * save current PSR: needed because we modify it | |
5917 | */ | |
5918 | psr = pfm_get_psr(); | |
5919 | ||
5920 | BUG_ON(psr & (IA64_PSR_I)); | |
5921 | ||
5922 | /* | |
5923 | * stop monitoring: | |
5924 | * This is the last instruction which may generate an overflow | |
5925 | * | |
5926 | * We do not need to set psr.sp because, it is irrelevant in kernel. | |
5927 | * It will be restored from ipsr when going back to user level | |
5928 | */ | |
5929 | pfm_clear_psr_up(); | |
5930 | ||
5931 | /* | |
5932 | * keep a copy of psr.up (for reload) | |
5933 | */ | |
5934 | ctx->ctx_saved_psr_up = psr & IA64_PSR_UP; | |
5935 | } | |
5936 | ||
5937 | static void | |
5938 | pfm_lazy_save_regs (struct task_struct *task) | |
5939 | { | |
5940 | pfm_context_t *ctx; | |
1da177e4 LT |
5941 | unsigned long flags; |
5942 | ||
5943 | { u64 psr = pfm_get_psr(); | |
5944 | BUG_ON(psr & IA64_PSR_UP); | |
5945 | } | |
5946 | ||
5947 | ctx = PFM_GET_CTX(task); | |
1da177e4 LT |
5948 | |
5949 | /* | |
5950 | * we need to mask PMU overflow here to | |
5951 | * make sure that we maintain pmc0 until | |
5952 | * we save it. overflow interrupts are | |
5953 | * treated as spurious if there is no | |
5954 | * owner. | |
5955 | * | |
5956 | * XXX: I don't think this is necessary | |
5957 | */ | |
5958 | PROTECT_CTX(ctx,flags); | |
5959 | ||
5960 | /* | |
5961 | * release ownership of this PMU. | |
5962 | * must be done before we save the registers. | |
5963 | * | |
5964 | * after this call any PMU interrupt is treated | |
5965 | * as spurious. | |
5966 | */ | |
5967 | SET_PMU_OWNER(NULL, NULL); | |
5968 | ||
5969 | /* | |
5970 | * save all the pmds we use | |
5971 | */ | |
35589a8f | 5972 | pfm_save_pmds(ctx->th_pmds, ctx->ctx_used_pmds[0]); |
1da177e4 LT |
5973 | |
5974 | /* | |
5975 | * save pmc0 ia64_srlz_d() done in pfm_save_pmds() | |
5976 | * it is needed to check for pended overflow | |
5977 | * on the restore path | |
5978 | */ | |
35589a8f | 5979 | ctx->th_pmcs[0] = ia64_get_pmc(0); |
1da177e4 LT |
5980 | |
5981 | /* | |
5982 | * unfreeze PMU if had pending overflows | |
5983 | */ | |
35589a8f | 5984 | if (ctx->th_pmcs[0] & ~0x1UL) pfm_unfreeze_pmu(); |
1da177e4 LT |
5985 | |
5986 | /* | |
5987 | * now get can unmask PMU interrupts, they will | |
5988 | * be treated as purely spurious and we will not | |
5989 | * lose any information | |
5990 | */ | |
5991 | UNPROTECT_CTX(ctx,flags); | |
5992 | } | |
5993 | #endif /* CONFIG_SMP */ | |
5994 | ||
5995 | #ifdef CONFIG_SMP | |
5996 | /* | |
5997 | * in 2.6, interrupts are masked when we come here and the runqueue lock is held | |
5998 | */ | |
5999 | void | |
6000 | pfm_load_regs (struct task_struct *task) | |
6001 | { | |
6002 | pfm_context_t *ctx; | |
1da177e4 LT |
6003 | unsigned long pmc_mask = 0UL, pmd_mask = 0UL; |
6004 | unsigned long flags; | |
6005 | u64 psr, psr_up; | |
6006 | int need_irq_resend; | |
6007 | ||
6008 | ctx = PFM_GET_CTX(task); | |
6009 | if (unlikely(ctx == NULL)) return; | |
6010 | ||
6011 | BUG_ON(GET_PMU_OWNER()); | |
6012 | ||
1da177e4 LT |
6013 | /* |
6014 | * possible on unload | |
6015 | */ | |
35589a8f | 6016 | if (unlikely((task->thread.flags & IA64_THREAD_PM_VALID) == 0)) return; |
1da177e4 LT |
6017 | |
6018 | /* | |
6019 | * we always come here with interrupts ALREADY disabled by | |
6020 | * the scheduler. So we simply need to protect against concurrent | |
6021 | * access, not CPU concurrency. | |
6022 | */ | |
6023 | flags = pfm_protect_ctx_ctxsw(ctx); | |
6024 | psr = pfm_get_psr(); | |
6025 | ||
6026 | need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND; | |
6027 | ||
6028 | BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP)); | |
6029 | BUG_ON(psr & IA64_PSR_I); | |
6030 | ||
6031 | if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) { | |
6450578f | 6032 | struct pt_regs *regs = task_pt_regs(task); |
1da177e4 LT |
6033 | |
6034 | BUG_ON(ctx->ctx_smpl_hdr); | |
6035 | ||
6036 | pfm_force_cleanup(ctx, regs); | |
6037 | ||
6038 | pfm_unprotect_ctx_ctxsw(ctx, flags); | |
6039 | ||
6040 | /* | |
6041 | * this one (kmalloc'ed) is fine with interrupts disabled | |
6042 | */ | |
6043 | pfm_context_free(ctx); | |
6044 | ||
6045 | return; | |
6046 | } | |
6047 | ||
6048 | /* | |
6049 | * we restore ALL the debug registers to avoid picking up | |
6050 | * stale state. | |
6051 | */ | |
6052 | if (ctx->ctx_fl_using_dbreg) { | |
6053 | pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); | |
6054 | pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); | |
6055 | } | |
6056 | /* | |
6057 | * retrieve saved psr.up | |
6058 | */ | |
6059 | psr_up = ctx->ctx_saved_psr_up; | |
6060 | ||
6061 | /* | |
6062 | * if we were the last user of the PMU on that CPU, | |
6063 | * then nothing to do except restore psr | |
6064 | */ | |
6065 | if (GET_LAST_CPU(ctx) == smp_processor_id() && ctx->ctx_last_activation == GET_ACTIVATION()) { | |
6066 | ||
6067 | /* | |
6068 | * retrieve partial reload masks (due to user modifications) | |
6069 | */ | |
6070 | pmc_mask = ctx->ctx_reload_pmcs[0]; | |
6071 | pmd_mask = ctx->ctx_reload_pmds[0]; | |
6072 | ||
6073 | } else { | |
6074 | /* | |
6075 | * To avoid leaking information to the user level when psr.sp=0, | |
6076 | * we must reload ALL implemented pmds (even the ones we don't use). | |
6077 | * In the kernel we only allow PFM_READ_PMDS on registers which | |
6078 | * we initialized or requested (sampling) so there is no risk there. | |
6079 | */ | |
6080 | pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0]; | |
6081 | ||
6082 | /* | |
6083 | * ALL accessible PMCs are systematically reloaded, unused registers | |
6084 | * get their default (from pfm_reset_pmu_state()) values to avoid picking | |
6085 | * up stale configuration. | |
6086 | * | |
6087 | * PMC0 is never in the mask. It is always restored separately. | |
6088 | */ | |
6089 | pmc_mask = ctx->ctx_all_pmcs[0]; | |
6090 | } | |
6091 | /* | |
6092 | * when context is MASKED, we will restore PMC with plm=0 | |
6093 | * and PMD with stale information, but that's ok, nothing | |
6094 | * will be captured. | |
6095 | * | |
6096 | * XXX: optimize here | |
6097 | */ | |
35589a8f KA |
6098 | if (pmd_mask) pfm_restore_pmds(ctx->th_pmds, pmd_mask); |
6099 | if (pmc_mask) pfm_restore_pmcs(ctx->th_pmcs, pmc_mask); | |
1da177e4 LT |
6100 | |
6101 | /* | |
6102 | * check for pending overflow at the time the state | |
6103 | * was saved. | |
6104 | */ | |
35589a8f | 6105 | if (unlikely(PMC0_HAS_OVFL(ctx->th_pmcs[0]))) { |
1da177e4 LT |
6106 | /* |
6107 | * reload pmc0 with the overflow information | |
6108 | * On McKinley PMU, this will trigger a PMU interrupt | |
6109 | */ | |
35589a8f | 6110 | ia64_set_pmc(0, ctx->th_pmcs[0]); |
1da177e4 | 6111 | ia64_srlz_d(); |
35589a8f | 6112 | ctx->th_pmcs[0] = 0UL; |
1da177e4 LT |
6113 | |
6114 | /* | |
6115 | * will replay the PMU interrupt | |
6116 | */ | |
c0ad90a3 | 6117 | if (need_irq_resend) ia64_resend_irq(IA64_PERFMON_VECTOR); |
1da177e4 LT |
6118 | |
6119 | pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++; | |
6120 | } | |
6121 | ||
6122 | /* | |
6123 | * we just did a reload, so we reset the partial reload fields | |
6124 | */ | |
6125 | ctx->ctx_reload_pmcs[0] = 0UL; | |
6126 | ctx->ctx_reload_pmds[0] = 0UL; | |
6127 | ||
6128 | SET_LAST_CPU(ctx, smp_processor_id()); | |
6129 | ||
6130 | /* | |
6131 | * dump activation value for this PMU | |
6132 | */ | |
6133 | INC_ACTIVATION(); | |
6134 | /* | |
6135 | * record current activation for this context | |
6136 | */ | |
6137 | SET_ACTIVATION(ctx); | |
6138 | ||
6139 | /* | |
6140 | * establish new ownership. | |
6141 | */ | |
6142 | SET_PMU_OWNER(task, ctx); | |
6143 | ||
6144 | /* | |
6145 | * restore the psr.up bit. measurement | |
6146 | * is active again. | |
6147 | * no PMU interrupt can happen at this point | |
6148 | * because we still have interrupts disabled. | |
6149 | */ | |
6150 | if (likely(psr_up)) pfm_set_psr_up(); | |
6151 | ||
6152 | /* | |
6153 | * allow concurrent access to context | |
6154 | */ | |
6155 | pfm_unprotect_ctx_ctxsw(ctx, flags); | |
6156 | } | |
6157 | #else /* !CONFIG_SMP */ | |
6158 | /* | |
6159 | * reload PMU state for UP kernels | |
6160 | * in 2.5 we come here with interrupts disabled | |
6161 | */ | |
6162 | void | |
6163 | pfm_load_regs (struct task_struct *task) | |
6164 | { | |
1da177e4 LT |
6165 | pfm_context_t *ctx; |
6166 | struct task_struct *owner; | |
6167 | unsigned long pmd_mask, pmc_mask; | |
6168 | u64 psr, psr_up; | |
6169 | int need_irq_resend; | |
6170 | ||
6171 | owner = GET_PMU_OWNER(); | |
6172 | ctx = PFM_GET_CTX(task); | |
1da177e4 LT |
6173 | psr = pfm_get_psr(); |
6174 | ||
6175 | BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP)); | |
6176 | BUG_ON(psr & IA64_PSR_I); | |
6177 | ||
6178 | /* | |
6179 | * we restore ALL the debug registers to avoid picking up | |
6180 | * stale state. | |
6181 | * | |
6182 | * This must be done even when the task is still the owner | |
6183 | * as the registers may have been modified via ptrace() | |
6184 | * (not perfmon) by the previous task. | |
6185 | */ | |
6186 | if (ctx->ctx_fl_using_dbreg) { | |
6187 | pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); | |
6188 | pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); | |
6189 | } | |
6190 | ||
6191 | /* | |
6192 | * retrieved saved psr.up | |
6193 | */ | |
6194 | psr_up = ctx->ctx_saved_psr_up; | |
6195 | need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND; | |
6196 | ||
6197 | /* | |
6198 | * short path, our state is still there, just | |
6199 | * need to restore psr and we go | |
6200 | * | |
6201 | * we do not touch either PMC nor PMD. the psr is not touched | |
6202 | * by the overflow_handler. So we are safe w.r.t. to interrupt | |
6203 | * concurrency even without interrupt masking. | |
6204 | */ | |
6205 | if (likely(owner == task)) { | |
6206 | if (likely(psr_up)) pfm_set_psr_up(); | |
6207 | return; | |
6208 | } | |
6209 | ||
6210 | /* | |
6211 | * someone else is still using the PMU, first push it out and | |
6212 | * then we'll be able to install our stuff ! | |
6213 | * | |
6214 | * Upon return, there will be no owner for the current PMU | |
6215 | */ | |
6216 | if (owner) pfm_lazy_save_regs(owner); | |
6217 | ||
6218 | /* | |
6219 | * To avoid leaking information to the user level when psr.sp=0, | |
6220 | * we must reload ALL implemented pmds (even the ones we don't use). | |
6221 | * In the kernel we only allow PFM_READ_PMDS on registers which | |
6222 | * we initialized or requested (sampling) so there is no risk there. | |
6223 | */ | |
6224 | pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0]; | |
6225 | ||
6226 | /* | |
6227 | * ALL accessible PMCs are systematically reloaded, unused registers | |
6228 | * get their default (from pfm_reset_pmu_state()) values to avoid picking | |
6229 | * up stale configuration. | |
6230 | * | |
6231 | * PMC0 is never in the mask. It is always restored separately | |
6232 | */ | |
6233 | pmc_mask = ctx->ctx_all_pmcs[0]; | |
6234 | ||
35589a8f KA |
6235 | pfm_restore_pmds(ctx->th_pmds, pmd_mask); |
6236 | pfm_restore_pmcs(ctx->th_pmcs, pmc_mask); | |
1da177e4 LT |
6237 | |
6238 | /* | |
6239 | * check for pending overflow at the time the state | |
6240 | * was saved. | |
6241 | */ | |
35589a8f | 6242 | if (unlikely(PMC0_HAS_OVFL(ctx->th_pmcs[0]))) { |
1da177e4 LT |
6243 | /* |
6244 | * reload pmc0 with the overflow information | |
6245 | * On McKinley PMU, this will trigger a PMU interrupt | |
6246 | */ | |
35589a8f | 6247 | ia64_set_pmc(0, ctx->th_pmcs[0]); |
1da177e4 LT |
6248 | ia64_srlz_d(); |
6249 | ||
35589a8f | 6250 | ctx->th_pmcs[0] = 0UL; |
1da177e4 LT |
6251 | |
6252 | /* | |
6253 | * will replay the PMU interrupt | |
6254 | */ | |
c0ad90a3 | 6255 | if (need_irq_resend) ia64_resend_irq(IA64_PERFMON_VECTOR); |
1da177e4 LT |
6256 | |
6257 | pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++; | |
6258 | } | |
6259 | ||
6260 | /* | |
6261 | * establish new ownership. | |
6262 | */ | |
6263 | SET_PMU_OWNER(task, ctx); | |
6264 | ||
6265 | /* | |
6266 | * restore the psr.up bit. measurement | |
6267 | * is active again. | |
6268 | * no PMU interrupt can happen at this point | |
6269 | * because we still have interrupts disabled. | |
6270 | */ | |
6271 | if (likely(psr_up)) pfm_set_psr_up(); | |
6272 | } | |
6273 | #endif /* CONFIG_SMP */ | |
6274 | ||
6275 | /* | |
6276 | * this function assumes monitoring is stopped | |
6277 | */ | |
6278 | static void | |
6279 | pfm_flush_pmds(struct task_struct *task, pfm_context_t *ctx) | |
6280 | { | |
6281 | u64 pmc0; | |
6282 | unsigned long mask2, val, pmd_val, ovfl_val; | |
6283 | int i, can_access_pmu = 0; | |
6284 | int is_self; | |
6285 | ||
6286 | /* | |
6287 | * is the caller the task being monitored (or which initiated the | |
6288 | * session for system wide measurements) | |
6289 | */ | |
6290 | is_self = ctx->ctx_task == task ? 1 : 0; | |
6291 | ||
6292 | /* | |
6293 | * can access PMU is task is the owner of the PMU state on the current CPU | |
6294 | * or if we are running on the CPU bound to the context in system-wide mode | |
6295 | * (that is not necessarily the task the context is attached to in this mode). | |
6296 | * In system-wide we always have can_access_pmu true because a task running on an | |
6297 | * invalid processor is flagged earlier in the call stack (see pfm_stop). | |
6298 | */ | |
6299 | can_access_pmu = (GET_PMU_OWNER() == task) || (ctx->ctx_fl_system && ctx->ctx_cpu == smp_processor_id()); | |
6300 | if (can_access_pmu) { | |
6301 | /* | |
6302 | * Mark the PMU as not owned | |
6303 | * This will cause the interrupt handler to do nothing in case an overflow | |
6304 | * interrupt was in-flight | |
6305 | * This also guarantees that pmc0 will contain the final state | |
6306 | * It virtually gives us full control on overflow processing from that point | |
6307 | * on. | |
6308 | */ | |
6309 | SET_PMU_OWNER(NULL, NULL); | |
6310 | DPRINT(("releasing ownership\n")); | |
6311 | ||
6312 | /* | |
6313 | * read current overflow status: | |
6314 | * | |
6315 | * we are guaranteed to read the final stable state | |
6316 | */ | |
6317 | ia64_srlz_d(); | |
6318 | pmc0 = ia64_get_pmc(0); /* slow */ | |
6319 | ||
6320 | /* | |
6321 | * reset freeze bit, overflow status information destroyed | |
6322 | */ | |
6323 | pfm_unfreeze_pmu(); | |
6324 | } else { | |
35589a8f | 6325 | pmc0 = ctx->th_pmcs[0]; |
1da177e4 LT |
6326 | /* |
6327 | * clear whatever overflow status bits there were | |
6328 | */ | |
35589a8f | 6329 | ctx->th_pmcs[0] = 0; |
1da177e4 LT |
6330 | } |
6331 | ovfl_val = pmu_conf->ovfl_val; | |
6332 | /* | |
6333 | * we save all the used pmds | |
6334 | * we take care of overflows for counting PMDs | |
6335 | * | |
6336 | * XXX: sampling situation is not taken into account here | |
6337 | */ | |
6338 | mask2 = ctx->ctx_used_pmds[0]; | |
6339 | ||
6340 | DPRINT(("is_self=%d ovfl_val=0x%lx mask2=0x%lx\n", is_self, ovfl_val, mask2)); | |
6341 | ||
6342 | for (i = 0; mask2; i++, mask2>>=1) { | |
6343 | ||
6344 | /* skip non used pmds */ | |
6345 | if ((mask2 & 0x1) == 0) continue; | |
6346 | ||
6347 | /* | |
6348 | * can access PMU always true in system wide mode | |
6349 | */ | |
35589a8f | 6350 | val = pmd_val = can_access_pmu ? ia64_get_pmd(i) : ctx->th_pmds[i]; |
1da177e4 LT |
6351 | |
6352 | if (PMD_IS_COUNTING(i)) { | |
6353 | DPRINT(("[%d] pmd[%d] ctx_pmd=0x%lx hw_pmd=0x%lx\n", | |
19c5870c | 6354 | task_pid_nr(task), |
1da177e4 LT |
6355 | i, |
6356 | ctx->ctx_pmds[i].val, | |
6357 | val & ovfl_val)); | |
6358 | ||
6359 | /* | |
6360 | * we rebuild the full 64 bit value of the counter | |
6361 | */ | |
6362 | val = ctx->ctx_pmds[i].val + (val & ovfl_val); | |
6363 | ||
6364 | /* | |
6365 | * now everything is in ctx_pmds[] and we need | |
6366 | * to clear the saved context from save_regs() such that | |
6367 | * pfm_read_pmds() gets the correct value | |
6368 | */ | |
6369 | pmd_val = 0UL; | |
6370 | ||
6371 | /* | |
6372 | * take care of overflow inline | |
6373 | */ | |
6374 | if (pmc0 & (1UL << i)) { | |
6375 | val += 1 + ovfl_val; | |
19c5870c | 6376 | DPRINT(("[%d] pmd[%d] overflowed\n", task_pid_nr(task), i)); |
1da177e4 LT |
6377 | } |
6378 | } | |
6379 | ||
19c5870c | 6380 | DPRINT(("[%d] ctx_pmd[%d]=0x%lx pmd_val=0x%lx\n", task_pid_nr(task), i, val, pmd_val)); |
1da177e4 | 6381 | |
35589a8f | 6382 | if (is_self) ctx->th_pmds[i] = pmd_val; |
1da177e4 LT |
6383 | |
6384 | ctx->ctx_pmds[i].val = val; | |
6385 | } | |
6386 | } | |
6387 | ||
6388 | static struct irqaction perfmon_irqaction = { | |
6389 | .handler = pfm_interrupt_handler, | |
1da177e4 LT |
6390 | .name = "perfmon" |
6391 | }; | |
6392 | ||
a1ecf7f6 TL |
6393 | static void |
6394 | pfm_alt_save_pmu_state(void *data) | |
6395 | { | |
6396 | struct pt_regs *regs; | |
6397 | ||
6450578f | 6398 | regs = task_pt_regs(current); |
a1ecf7f6 TL |
6399 | |
6400 | DPRINT(("called\n")); | |
6401 | ||
6402 | /* | |
6403 | * should not be necessary but | |
6404 | * let's take not risk | |
6405 | */ | |
6406 | pfm_clear_psr_up(); | |
6407 | pfm_clear_psr_pp(); | |
6408 | ia64_psr(regs)->pp = 0; | |
6409 | ||
6410 | /* | |
6411 | * This call is required | |
6412 | * May cause a spurious interrupt on some processors | |
6413 | */ | |
6414 | pfm_freeze_pmu(); | |
6415 | ||
6416 | ia64_srlz_d(); | |
6417 | } | |
6418 | ||
6419 | void | |
6420 | pfm_alt_restore_pmu_state(void *data) | |
6421 | { | |
6422 | struct pt_regs *regs; | |
6423 | ||
6450578f | 6424 | regs = task_pt_regs(current); |
a1ecf7f6 TL |
6425 | |
6426 | DPRINT(("called\n")); | |
6427 | ||
6428 | /* | |
6429 | * put PMU back in state expected | |
6430 | * by perfmon | |
6431 | */ | |
6432 | pfm_clear_psr_up(); | |
6433 | pfm_clear_psr_pp(); | |
6434 | ia64_psr(regs)->pp = 0; | |
6435 | ||
6436 | /* | |
6437 | * perfmon runs with PMU unfrozen at all times | |
6438 | */ | |
6439 | pfm_unfreeze_pmu(); | |
6440 | ||
6441 | ia64_srlz_d(); | |
6442 | } | |
6443 | ||
6444 | int | |
6445 | pfm_install_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl) | |
6446 | { | |
6447 | int ret, i; | |
6448 | int reserve_cpu; | |
6449 | ||
6450 | /* some sanity checks */ | |
6451 | if (hdl == NULL || hdl->handler == NULL) return -EINVAL; | |
6452 | ||
6453 | /* do the easy test first */ | |
6454 | if (pfm_alt_intr_handler) return -EBUSY; | |
6455 | ||
6456 | /* one at a time in the install or remove, just fail the others */ | |
6457 | if (!spin_trylock(&pfm_alt_install_check)) { | |
6458 | return -EBUSY; | |
6459 | } | |
6460 | ||
6461 | /* reserve our session */ | |
6462 | for_each_online_cpu(reserve_cpu) { | |
6463 | ret = pfm_reserve_session(NULL, 1, reserve_cpu); | |
6464 | if (ret) goto cleanup_reserve; | |
6465 | } | |
6466 | ||
6467 | /* save the current system wide pmu states */ | |
15c8b6c1 | 6468 | ret = on_each_cpu(pfm_alt_save_pmu_state, NULL, 1); |
a1ecf7f6 TL |
6469 | if (ret) { |
6470 | DPRINT(("on_each_cpu() failed: %d\n", ret)); | |
6471 | goto cleanup_reserve; | |
6472 | } | |
6473 | ||
6474 | /* officially change to the alternate interrupt handler */ | |
6475 | pfm_alt_intr_handler = hdl; | |
6476 | ||
6477 | spin_unlock(&pfm_alt_install_check); | |
6478 | ||
6479 | return 0; | |
6480 | ||
6481 | cleanup_reserve: | |
6482 | for_each_online_cpu(i) { | |
6483 | /* don't unreserve more than we reserved */ | |
6484 | if (i >= reserve_cpu) break; | |
6485 | ||
6486 | pfm_unreserve_session(NULL, 1, i); | |
6487 | } | |
6488 | ||
6489 | spin_unlock(&pfm_alt_install_check); | |
6490 | ||
6491 | return ret; | |
6492 | } | |
6493 | EXPORT_SYMBOL_GPL(pfm_install_alt_pmu_interrupt); | |
6494 | ||
6495 | int | |
6496 | pfm_remove_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl) | |
6497 | { | |
6498 | int i; | |
6499 | int ret; | |
6500 | ||
6501 | if (hdl == NULL) return -EINVAL; | |
6502 | ||
6503 | /* cannot remove someone else's handler! */ | |
6504 | if (pfm_alt_intr_handler != hdl) return -EINVAL; | |
6505 | ||
6506 | /* one at a time in the install or remove, just fail the others */ | |
6507 | if (!spin_trylock(&pfm_alt_install_check)) { | |
6508 | return -EBUSY; | |
6509 | } | |
6510 | ||
6511 | pfm_alt_intr_handler = NULL; | |
6512 | ||
15c8b6c1 | 6513 | ret = on_each_cpu(pfm_alt_restore_pmu_state, NULL, 1); |
a1ecf7f6 TL |
6514 | if (ret) { |
6515 | DPRINT(("on_each_cpu() failed: %d\n", ret)); | |
6516 | } | |
6517 | ||
6518 | for_each_online_cpu(i) { | |
6519 | pfm_unreserve_session(NULL, 1, i); | |
6520 | } | |
6521 | ||
6522 | spin_unlock(&pfm_alt_install_check); | |
6523 | ||
6524 | return 0; | |
6525 | } | |
6526 | EXPORT_SYMBOL_GPL(pfm_remove_alt_pmu_interrupt); | |
6527 | ||
1da177e4 LT |
6528 | /* |
6529 | * perfmon initialization routine, called from the initcall() table | |
6530 | */ | |
6531 | static int init_pfm_fs(void); | |
6532 | ||
6533 | static int __init | |
6534 | pfm_probe_pmu(void) | |
6535 | { | |
6536 | pmu_config_t **p; | |
6537 | int family; | |
6538 | ||
6539 | family = local_cpu_data->family; | |
6540 | p = pmu_confs; | |
6541 | ||
6542 | while(*p) { | |
6543 | if ((*p)->probe) { | |
6544 | if ((*p)->probe() == 0) goto found; | |
6545 | } else if ((*p)->pmu_family == family || (*p)->pmu_family == 0xff) { | |
6546 | goto found; | |
6547 | } | |
6548 | p++; | |
6549 | } | |
6550 | return -1; | |
6551 | found: | |
6552 | pmu_conf = *p; | |
6553 | return 0; | |
6554 | } | |
6555 | ||
5dfe4c96 | 6556 | static const struct file_operations pfm_proc_fops = { |
1da177e4 LT |
6557 | .open = pfm_proc_open, |
6558 | .read = seq_read, | |
6559 | .llseek = seq_lseek, | |
6560 | .release = seq_release, | |
6561 | }; | |
6562 | ||
6563 | int __init | |
6564 | pfm_init(void) | |
6565 | { | |
6566 | unsigned int n, n_counters, i; | |
6567 | ||
6568 | printk("perfmon: version %u.%u IRQ %u\n", | |
6569 | PFM_VERSION_MAJ, | |
6570 | PFM_VERSION_MIN, | |
6571 | IA64_PERFMON_VECTOR); | |
6572 | ||
6573 | if (pfm_probe_pmu()) { | |
6574 | printk(KERN_INFO "perfmon: disabled, there is no support for processor family %d\n", | |
6575 | local_cpu_data->family); | |
6576 | return -ENODEV; | |
6577 | } | |
6578 | ||
6579 | /* | |
6580 | * compute the number of implemented PMD/PMC from the | |
6581 | * description tables | |
6582 | */ | |
6583 | n = 0; | |
6584 | for (i=0; PMC_IS_LAST(i) == 0; i++) { | |
6585 | if (PMC_IS_IMPL(i) == 0) continue; | |
6586 | pmu_conf->impl_pmcs[i>>6] |= 1UL << (i&63); | |
6587 | n++; | |
6588 | } | |
6589 | pmu_conf->num_pmcs = n; | |
6590 | ||
6591 | n = 0; n_counters = 0; | |
6592 | for (i=0; PMD_IS_LAST(i) == 0; i++) { | |
6593 | if (PMD_IS_IMPL(i) == 0) continue; | |
6594 | pmu_conf->impl_pmds[i>>6] |= 1UL << (i&63); | |
6595 | n++; | |
6596 | if (PMD_IS_COUNTING(i)) n_counters++; | |
6597 | } | |
6598 | pmu_conf->num_pmds = n; | |
6599 | pmu_conf->num_counters = n_counters; | |
6600 | ||
6601 | /* | |
6602 | * sanity checks on the number of debug registers | |
6603 | */ | |
6604 | if (pmu_conf->use_rr_dbregs) { | |
6605 | if (pmu_conf->num_ibrs > IA64_NUM_DBG_REGS) { | |
6606 | printk(KERN_INFO "perfmon: unsupported number of code debug registers (%u)\n", pmu_conf->num_ibrs); | |
6607 | pmu_conf = NULL; | |
6608 | return -1; | |
6609 | } | |
6610 | if (pmu_conf->num_dbrs > IA64_NUM_DBG_REGS) { | |
6611 | printk(KERN_INFO "perfmon: unsupported number of data debug registers (%u)\n", pmu_conf->num_ibrs); | |
6612 | pmu_conf = NULL; | |
6613 | return -1; | |
6614 | } | |
6615 | } | |
6616 | ||
6617 | printk("perfmon: %s PMU detected, %u PMCs, %u PMDs, %u counters (%lu bits)\n", | |
6618 | pmu_conf->pmu_name, | |
6619 | pmu_conf->num_pmcs, | |
6620 | pmu_conf->num_pmds, | |
6621 | pmu_conf->num_counters, | |
6622 | ffz(pmu_conf->ovfl_val)); | |
6623 | ||
6624 | /* sanity check */ | |
35589a8f | 6625 | if (pmu_conf->num_pmds >= PFM_NUM_PMD_REGS || pmu_conf->num_pmcs >= PFM_NUM_PMC_REGS) { |
1da177e4 LT |
6626 | printk(KERN_ERR "perfmon: not enough pmc/pmd, perfmon disabled\n"); |
6627 | pmu_conf = NULL; | |
6628 | return -1; | |
6629 | } | |
6630 | ||
6631 | /* | |
6632 | * create /proc/perfmon (mostly for debugging purposes) | |
6633 | */ | |
e2363768 | 6634 | perfmon_dir = proc_create("perfmon", S_IRUGO, NULL, &pfm_proc_fops); |
1da177e4 LT |
6635 | if (perfmon_dir == NULL) { |
6636 | printk(KERN_ERR "perfmon: cannot create /proc entry, perfmon disabled\n"); | |
6637 | pmu_conf = NULL; | |
6638 | return -1; | |
6639 | } | |
1da177e4 LT |
6640 | |
6641 | /* | |
6642 | * create /proc/sys/kernel/perfmon (for debugging purposes) | |
6643 | */ | |
0b4d4147 | 6644 | pfm_sysctl_header = register_sysctl_table(pfm_sysctl_root); |
1da177e4 LT |
6645 | |
6646 | /* | |
6647 | * initialize all our spinlocks | |
6648 | */ | |
6649 | spin_lock_init(&pfm_sessions.pfs_lock); | |
6650 | spin_lock_init(&pfm_buffer_fmt_lock); | |
6651 | ||
6652 | init_pfm_fs(); | |
6653 | ||
6654 | for(i=0; i < NR_CPUS; i++) pfm_stats[i].pfm_ovfl_intr_cycles_min = ~0UL; | |
6655 | ||
6656 | return 0; | |
6657 | } | |
6658 | ||
6659 | __initcall(pfm_init); | |
6660 | ||
6661 | /* | |
6662 | * this function is called before pfm_init() | |
6663 | */ | |
6664 | void | |
6665 | pfm_init_percpu (void) | |
6666 | { | |
ff741906 | 6667 | static int first_time=1; |
1da177e4 LT |
6668 | /* |
6669 | * make sure no measurement is active | |
6670 | * (may inherit programmed PMCs from EFI). | |
6671 | */ | |
6672 | pfm_clear_psr_pp(); | |
6673 | pfm_clear_psr_up(); | |
6674 | ||
6675 | /* | |
6676 | * we run with the PMU not frozen at all times | |
6677 | */ | |
6678 | pfm_unfreeze_pmu(); | |
6679 | ||
ff741906 | 6680 | if (first_time) { |
1da177e4 | 6681 | register_percpu_irq(IA64_PERFMON_VECTOR, &perfmon_irqaction); |
ff741906 AR |
6682 | first_time=0; |
6683 | } | |
1da177e4 LT |
6684 | |
6685 | ia64_setreg(_IA64_REG_CR_PMV, IA64_PERFMON_VECTOR); | |
6686 | ia64_srlz_d(); | |
6687 | } | |
6688 | ||
6689 | /* | |
6690 | * used for debug purposes only | |
6691 | */ | |
6692 | void | |
6693 | dump_pmu_state(const char *from) | |
6694 | { | |
6695 | struct task_struct *task; | |
1da177e4 LT |
6696 | struct pt_regs *regs; |
6697 | pfm_context_t *ctx; | |
6698 | unsigned long psr, dcr, info, flags; | |
6699 | int i, this_cpu; | |
6700 | ||
6701 | local_irq_save(flags); | |
6702 | ||
6703 | this_cpu = smp_processor_id(); | |
6450578f | 6704 | regs = task_pt_regs(current); |
1da177e4 LT |
6705 | info = PFM_CPUINFO_GET(); |
6706 | dcr = ia64_getreg(_IA64_REG_CR_DCR); | |
6707 | ||
6708 | if (info == 0 && ia64_psr(regs)->pp == 0 && (dcr & IA64_DCR_PP) == 0) { | |
6709 | local_irq_restore(flags); | |
6710 | return; | |
6711 | } | |
6712 | ||
6713 | printk("CPU%d from %s() current [%d] iip=0x%lx %s\n", | |
6714 | this_cpu, | |
6715 | from, | |
19c5870c | 6716 | task_pid_nr(current), |
1da177e4 LT |
6717 | regs->cr_iip, |
6718 | current->comm); | |
6719 | ||
6720 | task = GET_PMU_OWNER(); | |
6721 | ctx = GET_PMU_CTX(); | |
6722 | ||
19c5870c | 6723 | printk("->CPU%d owner [%d] ctx=%p\n", this_cpu, task ? task_pid_nr(task) : -1, ctx); |
1da177e4 LT |
6724 | |
6725 | psr = pfm_get_psr(); | |
6726 | ||
6727 | printk("->CPU%d pmc0=0x%lx psr.pp=%d psr.up=%d dcr.pp=%d syst_info=0x%lx user_psr.up=%d user_psr.pp=%d\n", | |
6728 | this_cpu, | |
6729 | ia64_get_pmc(0), | |
6730 | psr & IA64_PSR_PP ? 1 : 0, | |
6731 | psr & IA64_PSR_UP ? 1 : 0, | |
6732 | dcr & IA64_DCR_PP ? 1 : 0, | |
6733 | info, | |
6734 | ia64_psr(regs)->up, | |
6735 | ia64_psr(regs)->pp); | |
6736 | ||
6737 | ia64_psr(regs)->up = 0; | |
6738 | ia64_psr(regs)->pp = 0; | |
6739 | ||
1da177e4 LT |
6740 | for (i=1; PMC_IS_LAST(i) == 0; i++) { |
6741 | if (PMC_IS_IMPL(i) == 0) continue; | |
35589a8f | 6742 | printk("->CPU%d pmc[%d]=0x%lx thread_pmc[%d]=0x%lx\n", this_cpu, i, ia64_get_pmc(i), i, ctx->th_pmcs[i]); |
1da177e4 LT |
6743 | } |
6744 | ||
6745 | for (i=1; PMD_IS_LAST(i) == 0; i++) { | |
6746 | if (PMD_IS_IMPL(i) == 0) continue; | |
35589a8f | 6747 | printk("->CPU%d pmd[%d]=0x%lx thread_pmd[%d]=0x%lx\n", this_cpu, i, ia64_get_pmd(i), i, ctx->th_pmds[i]); |
1da177e4 LT |
6748 | } |
6749 | ||
6750 | if (ctx) { | |
6751 | printk("->CPU%d ctx_state=%d vaddr=%p addr=%p fd=%d ctx_task=[%d] saved_psr_up=0x%lx\n", | |
6752 | this_cpu, | |
6753 | ctx->ctx_state, | |
6754 | ctx->ctx_smpl_vaddr, | |
6755 | ctx->ctx_smpl_hdr, | |
6756 | ctx->ctx_msgq_head, | |
6757 | ctx->ctx_msgq_tail, | |
6758 | ctx->ctx_saved_psr_up); | |
6759 | } | |
6760 | local_irq_restore(flags); | |
6761 | } | |
6762 | ||
6763 | /* | |
6764 | * called from process.c:copy_thread(). task is new child. | |
6765 | */ | |
6766 | void | |
6767 | pfm_inherit(struct task_struct *task, struct pt_regs *regs) | |
6768 | { | |
6769 | struct thread_struct *thread; | |
6770 | ||
19c5870c | 6771 | DPRINT(("perfmon: pfm_inherit clearing state for [%d]\n", task_pid_nr(task))); |
1da177e4 LT |
6772 | |
6773 | thread = &task->thread; | |
6774 | ||
6775 | /* | |
6776 | * cut links inherited from parent (current) | |
6777 | */ | |
6778 | thread->pfm_context = NULL; | |
6779 | ||
6780 | PFM_SET_WORK_PENDING(task, 0); | |
6781 | ||
6782 | /* | |
6783 | * the psr bits are already set properly in copy_threads() | |
6784 | */ | |
6785 | } | |
6786 | #else /* !CONFIG_PERFMON */ | |
6787 | asmlinkage long | |
6788 | sys_perfmonctl (int fd, int cmd, void *arg, int count) | |
6789 | { | |
6790 | return -ENOSYS; | |
6791 | } | |
6792 | #endif /* CONFIG_PERFMON */ |