Commit | Line | Data |
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bc0c38d1 SR |
1 | #ifndef _LINUX_KERNEL_TRACE_H |
2 | #define _LINUX_KERNEL_TRACE_H | |
3 | ||
4 | #include <linux/fs.h> | |
5 | #include <asm/atomic.h> | |
6 | #include <linux/sched.h> | |
7 | #include <linux/clocksource.h> | |
3928a8a2 | 8 | #include <linux/ring_buffer.h> |
bd8ac686 | 9 | #include <linux/mmiotrace.h> |
d13744cd | 10 | #include <linux/ftrace.h> |
3f5ec136 | 11 | #include <trace/boot.h> |
bc0c38d1 | 12 | |
72829bc3 TG |
13 | enum trace_type { |
14 | __TRACE_FIRST_TYPE = 0, | |
15 | ||
16 | TRACE_FN, | |
17 | TRACE_CTX, | |
18 | TRACE_WAKE, | |
dd0e545f | 19 | TRACE_CONT, |
72829bc3 | 20 | TRACE_STACK, |
dd0e545f | 21 | TRACE_PRINT, |
72829bc3 | 22 | TRACE_SPECIAL, |
bd8ac686 PP |
23 | TRACE_MMIO_RW, |
24 | TRACE_MMIO_MAP, | |
9f029e83 | 25 | TRACE_BRANCH, |
74239072 FW |
26 | TRACE_BOOT_CALL, |
27 | TRACE_BOOT_RET, | |
15e6cb36 | 28 | TRACE_FN_RET, |
72829bc3 TG |
29 | |
30 | __TRACE_LAST_TYPE | |
31 | }; | |
32 | ||
777e208d SR |
33 | /* |
34 | * The trace entry - the most basic unit of tracing. This is what | |
35 | * is printed in the end as a single line in the trace output, such as: | |
36 | * | |
37 | * bash-15816 [01] 235.197585: idle_cpu <- irq_enter | |
38 | */ | |
39 | struct trace_entry { | |
40 | unsigned char type; | |
41 | unsigned char cpu; | |
42 | unsigned char flags; | |
43 | unsigned char preempt_count; | |
44 | int pid; | |
45 | }; | |
46 | ||
bc0c38d1 SR |
47 | /* |
48 | * Function trace entry - function address and parent function addres: | |
49 | */ | |
50 | struct ftrace_entry { | |
777e208d | 51 | struct trace_entry ent; |
bc0c38d1 SR |
52 | unsigned long ip; |
53 | unsigned long parent_ip; | |
54 | }; | |
15e6cb36 FW |
55 | |
56 | /* Function return entry */ | |
57 | struct ftrace_ret_entry { | |
58 | struct trace_entry ent; | |
59 | unsigned long ip; | |
60 | unsigned long parent_ip; | |
61 | unsigned long long calltime; | |
62 | unsigned long long rettime; | |
0231022c | 63 | unsigned long overrun; |
15e6cb36 | 64 | }; |
d13744cd | 65 | extern struct tracer boot_tracer; |
bc0c38d1 SR |
66 | |
67 | /* | |
68 | * Context switch trace entry - which task (and prio) we switched from/to: | |
69 | */ | |
70 | struct ctx_switch_entry { | |
777e208d | 71 | struct trace_entry ent; |
bc0c38d1 SR |
72 | unsigned int prev_pid; |
73 | unsigned char prev_prio; | |
74 | unsigned char prev_state; | |
75 | unsigned int next_pid; | |
76 | unsigned char next_prio; | |
bac524d3 | 77 | unsigned char next_state; |
80b5e940 | 78 | unsigned int next_cpu; |
bc0c38d1 SR |
79 | }; |
80 | ||
f0a920d5 IM |
81 | /* |
82 | * Special (free-form) trace entry: | |
83 | */ | |
84 | struct special_entry { | |
777e208d | 85 | struct trace_entry ent; |
f0a920d5 IM |
86 | unsigned long arg1; |
87 | unsigned long arg2; | |
88 | unsigned long arg3; | |
89 | }; | |
90 | ||
86387f7e IM |
91 | /* |
92 | * Stack-trace entry: | |
93 | */ | |
94 | ||
74f4e369 | 95 | #define FTRACE_STACK_ENTRIES 8 |
86387f7e IM |
96 | |
97 | struct stack_entry { | |
777e208d | 98 | struct trace_entry ent; |
86387f7e IM |
99 | unsigned long caller[FTRACE_STACK_ENTRIES]; |
100 | }; | |
101 | ||
dd0e545f SR |
102 | /* |
103 | * ftrace_printk entry: | |
104 | */ | |
105 | struct print_entry { | |
777e208d | 106 | struct trace_entry ent; |
dd0e545f SR |
107 | unsigned long ip; |
108 | char buf[]; | |
109 | }; | |
110 | ||
777e208d SR |
111 | #define TRACE_OLD_SIZE 88 |
112 | ||
113 | struct trace_field_cont { | |
114 | unsigned char type; | |
115 | /* Temporary till we get rid of this completely */ | |
116 | char buf[TRACE_OLD_SIZE - 1]; | |
117 | }; | |
118 | ||
119 | struct trace_mmiotrace_rw { | |
120 | struct trace_entry ent; | |
121 | struct mmiotrace_rw rw; | |
122 | }; | |
123 | ||
124 | struct trace_mmiotrace_map { | |
125 | struct trace_entry ent; | |
126 | struct mmiotrace_map map; | |
127 | }; | |
128 | ||
74239072 | 129 | struct trace_boot_call { |
777e208d | 130 | struct trace_entry ent; |
74239072 FW |
131 | struct boot_trace_call boot_call; |
132 | }; | |
133 | ||
134 | struct trace_boot_ret { | |
135 | struct trace_entry ent; | |
136 | struct boot_trace_ret boot_ret; | |
777e208d SR |
137 | }; |
138 | ||
52f232cb SR |
139 | #define TRACE_FUNC_SIZE 30 |
140 | #define TRACE_FILE_SIZE 20 | |
9f029e83 | 141 | struct trace_branch { |
52f232cb SR |
142 | struct trace_entry ent; |
143 | unsigned line; | |
144 | char func[TRACE_FUNC_SIZE+1]; | |
145 | char file[TRACE_FILE_SIZE+1]; | |
146 | char correct; | |
147 | }; | |
148 | ||
fc5e27ae PP |
149 | /* |
150 | * trace_flag_type is an enumeration that holds different | |
151 | * states when a trace occurs. These are: | |
9244489a SR |
152 | * IRQS_OFF - interrupts were disabled |
153 | * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags | |
154 | * NEED_RESCED - reschedule is requested | |
155 | * HARDIRQ - inside an interrupt handler | |
156 | * SOFTIRQ - inside a softirq handler | |
157 | * CONT - multiple entries hold the trace item | |
fc5e27ae PP |
158 | */ |
159 | enum trace_flag_type { | |
160 | TRACE_FLAG_IRQS_OFF = 0x01, | |
9244489a SR |
161 | TRACE_FLAG_IRQS_NOSUPPORT = 0x02, |
162 | TRACE_FLAG_NEED_RESCHED = 0x04, | |
163 | TRACE_FLAG_HARDIRQ = 0x08, | |
164 | TRACE_FLAG_SOFTIRQ = 0x10, | |
165 | TRACE_FLAG_CONT = 0x20, | |
fc5e27ae PP |
166 | }; |
167 | ||
5bf9a1ee | 168 | #define TRACE_BUF_SIZE 1024 |
bc0c38d1 SR |
169 | |
170 | /* | |
171 | * The CPU trace array - it consists of thousands of trace entries | |
172 | * plus some other descriptor data: (for example which task started | |
173 | * the trace, etc.) | |
174 | */ | |
175 | struct trace_array_cpu { | |
bc0c38d1 | 176 | atomic_t disabled; |
4e3c3333 | 177 | |
c7aafc54 | 178 | /* these fields get copied into max-trace: */ |
c7aafc54 | 179 | unsigned long trace_idx; |
53d0aa77 | 180 | unsigned long overrun; |
bc0c38d1 SR |
181 | unsigned long saved_latency; |
182 | unsigned long critical_start; | |
183 | unsigned long critical_end; | |
184 | unsigned long critical_sequence; | |
185 | unsigned long nice; | |
186 | unsigned long policy; | |
187 | unsigned long rt_priority; | |
188 | cycle_t preempt_timestamp; | |
189 | pid_t pid; | |
190 | uid_t uid; | |
191 | char comm[TASK_COMM_LEN]; | |
192 | }; | |
193 | ||
194 | struct trace_iterator; | |
195 | ||
196 | /* | |
197 | * The trace array - an array of per-CPU trace arrays. This is the | |
198 | * highest level data structure that individual tracers deal with. | |
199 | * They have on/off state as well: | |
200 | */ | |
201 | struct trace_array { | |
3928a8a2 | 202 | struct ring_buffer *buffer; |
bc0c38d1 | 203 | unsigned long entries; |
bc0c38d1 SR |
204 | int cpu; |
205 | cycle_t time_start; | |
b3806b43 | 206 | struct task_struct *waiter; |
bc0c38d1 SR |
207 | struct trace_array_cpu *data[NR_CPUS]; |
208 | }; | |
209 | ||
7104f300 SR |
210 | #define FTRACE_CMP_TYPE(var, type) \ |
211 | __builtin_types_compatible_p(typeof(var), type *) | |
212 | ||
213 | #undef IF_ASSIGN | |
214 | #define IF_ASSIGN(var, entry, etype, id) \ | |
215 | if (FTRACE_CMP_TYPE(var, etype)) { \ | |
216 | var = (typeof(var))(entry); \ | |
217 | WARN_ON(id && (entry)->type != id); \ | |
218 | break; \ | |
219 | } | |
220 | ||
221 | /* Will cause compile errors if type is not found. */ | |
222 | extern void __ftrace_bad_type(void); | |
223 | ||
224 | /* | |
225 | * The trace_assign_type is a verifier that the entry type is | |
226 | * the same as the type being assigned. To add new types simply | |
227 | * add a line with the following format: | |
228 | * | |
229 | * IF_ASSIGN(var, ent, type, id); | |
230 | * | |
231 | * Where "type" is the trace type that includes the trace_entry | |
232 | * as the "ent" item. And "id" is the trace identifier that is | |
233 | * used in the trace_type enum. | |
234 | * | |
235 | * If the type can have more than one id, then use zero. | |
236 | */ | |
237 | #define trace_assign_type(var, ent) \ | |
238 | do { \ | |
239 | IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ | |
240 | IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ | |
241 | IF_ASSIGN(var, ent, struct trace_field_cont, TRACE_CONT); \ | |
242 | IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ | |
243 | IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ | |
244 | IF_ASSIGN(var, ent, struct special_entry, 0); \ | |
245 | IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ | |
246 | TRACE_MMIO_RW); \ | |
247 | IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ | |
248 | TRACE_MMIO_MAP); \ | |
74239072 FW |
249 | IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\ |
250 | IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\ | |
9f029e83 | 251 | IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ |
74239072 | 252 | IF_ASSIGN(var, ent, struct ftrace_ret_entry, TRACE_FN_RET);\ |
7104f300 SR |
253 | __ftrace_bad_type(); \ |
254 | } while (0) | |
2c4f035f FW |
255 | |
256 | /* Return values for print_line callback */ | |
257 | enum print_line_t { | |
258 | TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */ | |
259 | TRACE_TYPE_HANDLED = 1, | |
260 | TRACE_TYPE_UNHANDLED = 2 /* Relay to other output functions */ | |
261 | }; | |
262 | ||
adf9f195 FW |
263 | |
264 | /* | |
265 | * An option specific to a tracer. This is a boolean value. | |
266 | * The bit is the bit index that sets its value on the | |
267 | * flags value in struct tracer_flags. | |
268 | */ | |
269 | struct tracer_opt { | |
270 | const char *name; /* Will appear on the trace_options file */ | |
271 | u32 bit; /* Mask assigned in val field in tracer_flags */ | |
272 | }; | |
273 | ||
274 | /* | |
275 | * The set of specific options for a tracer. Your tracer | |
276 | * have to set the initial value of the flags val. | |
277 | */ | |
278 | struct tracer_flags { | |
279 | u32 val; | |
280 | struct tracer_opt *opts; | |
281 | }; | |
282 | ||
283 | /* Makes more easy to define a tracer opt */ | |
284 | #define TRACER_OPT(s, b) .name = #s, .bit = b | |
285 | ||
bc0c38d1 SR |
286 | /* |
287 | * A specific tracer, represented by methods that operate on a trace array: | |
288 | */ | |
289 | struct tracer { | |
290 | const char *name; | |
1c80025a FW |
291 | /* Your tracer should raise a warning if init fails */ |
292 | int (*init)(struct trace_array *tr); | |
bc0c38d1 | 293 | void (*reset)(struct trace_array *tr); |
9036990d SR |
294 | void (*start)(struct trace_array *tr); |
295 | void (*stop)(struct trace_array *tr); | |
bc0c38d1 | 296 | void (*open)(struct trace_iterator *iter); |
107bad8b | 297 | void (*pipe_open)(struct trace_iterator *iter); |
bc0c38d1 | 298 | void (*close)(struct trace_iterator *iter); |
107bad8b SR |
299 | ssize_t (*read)(struct trace_iterator *iter, |
300 | struct file *filp, char __user *ubuf, | |
301 | size_t cnt, loff_t *ppos); | |
60a11774 SR |
302 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
303 | int (*selftest)(struct tracer *trace, | |
304 | struct trace_array *tr); | |
305 | #endif | |
2c4f035f | 306 | enum print_line_t (*print_line)(struct trace_iterator *iter); |
adf9f195 FW |
307 | /* If you handled the flag setting, return 0 */ |
308 | int (*set_flag)(u32 old_flags, u32 bit, int set); | |
bc0c38d1 SR |
309 | struct tracer *next; |
310 | int print_max; | |
adf9f195 | 311 | struct tracer_flags *flags; |
bc0c38d1 SR |
312 | }; |
313 | ||
214023c3 SR |
314 | struct trace_seq { |
315 | unsigned char buffer[PAGE_SIZE]; | |
316 | unsigned int len; | |
6c6c2796 | 317 | unsigned int readpos; |
214023c3 SR |
318 | }; |
319 | ||
bc0c38d1 SR |
320 | /* |
321 | * Trace iterator - used by printout routines who present trace | |
322 | * results to users and which routines might sleep, etc: | |
323 | */ | |
324 | struct trace_iterator { | |
325 | struct trace_array *tr; | |
326 | struct tracer *trace; | |
107bad8b | 327 | void *private; |
3928a8a2 | 328 | struct ring_buffer_iter *buffer_iter[NR_CPUS]; |
4e3c3333 | 329 | |
53d0aa77 SR |
330 | /* The below is zeroed out in pipe_read */ |
331 | struct trace_seq seq; | |
bc0c38d1 | 332 | struct trace_entry *ent; |
4e3c3333 | 333 | int cpu; |
3928a8a2 | 334 | u64 ts; |
4e3c3333 | 335 | |
bc0c38d1 SR |
336 | unsigned long iter_flags; |
337 | loff_t pos; | |
4c11d7ae | 338 | long idx; |
a309720c SR |
339 | |
340 | cpumask_t started; | |
bc0c38d1 SR |
341 | }; |
342 | ||
9036990d | 343 | int tracing_is_enabled(void); |
45dcd8b8 | 344 | void trace_wake_up(void); |
3928a8a2 | 345 | void tracing_reset(struct trace_array *tr, int cpu); |
bc0c38d1 SR |
346 | int tracing_open_generic(struct inode *inode, struct file *filp); |
347 | struct dentry *tracing_init_dentry(void); | |
d618b3e6 IM |
348 | void init_tracer_sysprof_debugfs(struct dentry *d_tracer); |
349 | ||
45dcd8b8 PP |
350 | struct trace_entry *tracing_get_trace_entry(struct trace_array *tr, |
351 | struct trace_array_cpu *data); | |
352 | void tracing_generic_entry_update(struct trace_entry *entry, | |
38697053 SR |
353 | unsigned long flags, |
354 | int pc); | |
45dcd8b8 | 355 | |
bc0c38d1 SR |
356 | void ftrace(struct trace_array *tr, |
357 | struct trace_array_cpu *data, | |
358 | unsigned long ip, | |
359 | unsigned long parent_ip, | |
38697053 | 360 | unsigned long flags, int pc); |
bc0c38d1 SR |
361 | void tracing_sched_switch_trace(struct trace_array *tr, |
362 | struct trace_array_cpu *data, | |
363 | struct task_struct *prev, | |
364 | struct task_struct *next, | |
38697053 | 365 | unsigned long flags, int pc); |
bc0c38d1 | 366 | void tracing_record_cmdline(struct task_struct *tsk); |
57422797 IM |
367 | |
368 | void tracing_sched_wakeup_trace(struct trace_array *tr, | |
369 | struct trace_array_cpu *data, | |
370 | struct task_struct *wakee, | |
371 | struct task_struct *cur, | |
38697053 | 372 | unsigned long flags, int pc); |
f0a920d5 IM |
373 | void trace_special(struct trace_array *tr, |
374 | struct trace_array_cpu *data, | |
375 | unsigned long arg1, | |
376 | unsigned long arg2, | |
38697053 | 377 | unsigned long arg3, int pc); |
6fb44b71 SR |
378 | void trace_function(struct trace_array *tr, |
379 | struct trace_array_cpu *data, | |
380 | unsigned long ip, | |
381 | unsigned long parent_ip, | |
38697053 | 382 | unsigned long flags, int pc); |
15e6cb36 FW |
383 | void |
384 | trace_function_return(struct ftrace_retfunc *trace); | |
bc0c38d1 | 385 | |
41bc8144 SR |
386 | void tracing_start_cmdline_record(void); |
387 | void tracing_stop_cmdline_record(void); | |
e168e051 SR |
388 | void tracing_sched_switch_assign_trace(struct trace_array *tr); |
389 | void tracing_stop_sched_switch_record(void); | |
390 | void tracing_start_sched_switch_record(void); | |
bc0c38d1 SR |
391 | int register_tracer(struct tracer *type); |
392 | void unregister_tracer(struct tracer *type); | |
393 | ||
394 | extern unsigned long nsecs_to_usecs(unsigned long nsecs); | |
395 | ||
396 | extern unsigned long tracing_max_latency; | |
397 | extern unsigned long tracing_thresh; | |
398 | ||
399 | void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); | |
400 | void update_max_tr_single(struct trace_array *tr, | |
401 | struct task_struct *tsk, int cpu); | |
402 | ||
e309b41d | 403 | extern cycle_t ftrace_now(int cpu); |
bc0c38d1 | 404 | |
606576ce | 405 | #ifdef CONFIG_FUNCTION_TRACER |
001b6767 SR |
406 | void tracing_start_function_trace(void); |
407 | void tracing_stop_function_trace(void); | |
408 | #else | |
409 | # define tracing_start_function_trace() do { } while (0) | |
410 | # define tracing_stop_function_trace() do { } while (0) | |
411 | #endif | |
412 | ||
bc0c38d1 SR |
413 | #ifdef CONFIG_CONTEXT_SWITCH_TRACER |
414 | typedef void | |
415 | (*tracer_switch_func_t)(void *private, | |
5b82a1b0 | 416 | void *__rq, |
bc0c38d1 SR |
417 | struct task_struct *prev, |
418 | struct task_struct *next); | |
419 | ||
420 | struct tracer_switch_ops { | |
421 | tracer_switch_func_t func; | |
422 | void *private; | |
423 | struct tracer_switch_ops *next; | |
424 | }; | |
425 | ||
bc0c38d1 SR |
426 | #endif /* CONFIG_CONTEXT_SWITCH_TRACER */ |
427 | ||
428 | #ifdef CONFIG_DYNAMIC_FTRACE | |
429 | extern unsigned long ftrace_update_tot_cnt; | |
d05cdb25 SR |
430 | #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func |
431 | extern int DYN_FTRACE_TEST_NAME(void); | |
bc0c38d1 SR |
432 | #endif |
433 | ||
60a11774 | 434 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
60a11774 SR |
435 | extern int trace_selftest_startup_function(struct tracer *trace, |
436 | struct trace_array *tr); | |
60a11774 SR |
437 | extern int trace_selftest_startup_irqsoff(struct tracer *trace, |
438 | struct trace_array *tr); | |
60a11774 SR |
439 | extern int trace_selftest_startup_preemptoff(struct tracer *trace, |
440 | struct trace_array *tr); | |
60a11774 SR |
441 | extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace, |
442 | struct trace_array *tr); | |
60a11774 SR |
443 | extern int trace_selftest_startup_wakeup(struct tracer *trace, |
444 | struct trace_array *tr); | |
fb1b6d8b SN |
445 | extern int trace_selftest_startup_nop(struct tracer *trace, |
446 | struct trace_array *tr); | |
60a11774 SR |
447 | extern int trace_selftest_startup_sched_switch(struct tracer *trace, |
448 | struct trace_array *tr); | |
a6dd24f8 IM |
449 | extern int trace_selftest_startup_sysprof(struct tracer *trace, |
450 | struct trace_array *tr); | |
80e5ea45 SR |
451 | extern int trace_selftest_startup_branch(struct tracer *trace, |
452 | struct trace_array *tr); | |
60a11774 SR |
453 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
454 | ||
c7aafc54 | 455 | extern void *head_page(struct trace_array_cpu *data); |
72829bc3 | 456 | extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...); |
fc5e27ae PP |
457 | extern void trace_seq_print_cont(struct trace_seq *s, |
458 | struct trace_iterator *iter); | |
15e6cb36 FW |
459 | |
460 | extern int | |
461 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, | |
462 | unsigned long sym_flags); | |
6c6c2796 PP |
463 | extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, |
464 | size_t cnt); | |
72829bc3 | 465 | extern long ns2usecs(cycle_t nsec); |
801fe400 | 466 | extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args); |
c7aafc54 | 467 | |
4e655519 IM |
468 | extern unsigned long trace_flags; |
469 | ||
15e6cb36 FW |
470 | /* Standard output formatting function used for function return traces */ |
471 | #ifdef CONFIG_FUNCTION_RET_TRACER | |
472 | extern enum print_line_t print_return_function(struct trace_iterator *iter); | |
473 | #else | |
474 | static inline enum print_line_t | |
475 | print_return_function(struct trace_iterator *iter) | |
476 | { | |
477 | return TRACE_TYPE_UNHANDLED; | |
478 | } | |
479 | #endif | |
480 | ||
4fcdae83 SR |
481 | /* |
482 | * trace_iterator_flags is an enumeration that defines bit | |
483 | * positions into trace_flags that controls the output. | |
484 | * | |
485 | * NOTE: These bits must match the trace_options array in | |
486 | * trace.c. | |
487 | */ | |
4e655519 IM |
488 | enum trace_iterator_flags { |
489 | TRACE_ITER_PRINT_PARENT = 0x01, | |
490 | TRACE_ITER_SYM_OFFSET = 0x02, | |
491 | TRACE_ITER_SYM_ADDR = 0x04, | |
492 | TRACE_ITER_VERBOSE = 0x08, | |
493 | TRACE_ITER_RAW = 0x10, | |
494 | TRACE_ITER_HEX = 0x20, | |
495 | TRACE_ITER_BIN = 0x40, | |
496 | TRACE_ITER_BLOCK = 0x80, | |
497 | TRACE_ITER_STACKTRACE = 0x100, | |
4ac3ba41 | 498 | TRACE_ITER_SCHED_TREE = 0x200, |
f09ce573 | 499 | TRACE_ITER_PRINTK = 0x400, |
b2a866f9 | 500 | TRACE_ITER_PREEMPTONLY = 0x800, |
9f029e83 | 501 | TRACE_ITER_BRANCH = 0x1000, |
12ef7d44 | 502 | TRACE_ITER_ANNOTATE = 0x2000, |
4e655519 IM |
503 | }; |
504 | ||
15e6cb36 FW |
505 | /* |
506 | * TRACE_ITER_SYM_MASK masks the options in trace_flags that | |
507 | * control the output of kernel symbols. | |
508 | */ | |
509 | #define TRACE_ITER_SYM_MASK \ | |
510 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
511 | ||
43a15386 FW |
512 | extern struct tracer nop_trace; |
513 | ||
8f0a056f SR |
514 | /** |
515 | * ftrace_preempt_disable - disable preemption scheduler safe | |
516 | * | |
517 | * When tracing can happen inside the scheduler, there exists | |
518 | * cases that the tracing might happen before the need_resched | |
519 | * flag is checked. If this happens and the tracer calls | |
520 | * preempt_enable (after a disable), a schedule might take place | |
521 | * causing an infinite recursion. | |
522 | * | |
523 | * To prevent this, we read the need_recshed flag before | |
524 | * disabling preemption. When we want to enable preemption we | |
525 | * check the flag, if it is set, then we call preempt_enable_no_resched. | |
526 | * Otherwise, we call preempt_enable. | |
527 | * | |
528 | * The rational for doing the above is that if need resched is set | |
529 | * and we have yet to reschedule, we are either in an atomic location | |
530 | * (where we do not need to check for scheduling) or we are inside | |
531 | * the scheduler and do not want to resched. | |
532 | */ | |
533 | static inline int ftrace_preempt_disable(void) | |
534 | { | |
535 | int resched; | |
536 | ||
537 | resched = need_resched(); | |
538 | preempt_disable_notrace(); | |
539 | ||
540 | return resched; | |
541 | } | |
542 | ||
543 | /** | |
544 | * ftrace_preempt_enable - enable preemption scheduler safe | |
545 | * @resched: the return value from ftrace_preempt_disable | |
546 | * | |
547 | * This is a scheduler safe way to enable preemption and not miss | |
548 | * any preemption checks. The disabled saved the state of preemption. | |
549 | * If resched is set, then we were either inside an atomic or | |
550 | * are inside the scheduler (we would have already scheduled | |
551 | * otherwise). In this case, we do not want to call normal | |
552 | * preempt_enable, but preempt_enable_no_resched instead. | |
553 | */ | |
554 | static inline void ftrace_preempt_enable(int resched) | |
555 | { | |
556 | if (resched) | |
557 | preempt_enable_no_resched_notrace(); | |
558 | else | |
559 | preempt_enable_notrace(); | |
560 | } | |
561 | ||
2ed84eeb | 562 | #ifdef CONFIG_BRANCH_TRACER |
9f029e83 SR |
563 | extern int enable_branch_tracing(struct trace_array *tr); |
564 | extern void disable_branch_tracing(void); | |
565 | static inline int trace_branch_enable(struct trace_array *tr) | |
52f232cb | 566 | { |
9f029e83 SR |
567 | if (trace_flags & TRACE_ITER_BRANCH) |
568 | return enable_branch_tracing(tr); | |
52f232cb SR |
569 | return 0; |
570 | } | |
9f029e83 | 571 | static inline void trace_branch_disable(void) |
52f232cb SR |
572 | { |
573 | /* due to races, always disable */ | |
9f029e83 | 574 | disable_branch_tracing(); |
52f232cb SR |
575 | } |
576 | #else | |
9f029e83 | 577 | static inline int trace_branch_enable(struct trace_array *tr) |
52f232cb SR |
578 | { |
579 | return 0; | |
580 | } | |
9f029e83 | 581 | static inline void trace_branch_disable(void) |
52f232cb SR |
582 | { |
583 | } | |
2ed84eeb | 584 | #endif /* CONFIG_BRANCH_TRACER */ |
52f232cb | 585 | |
bc0c38d1 | 586 | #endif /* _LINUX_KERNEL_TRACE_H */ |