Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * arch/s390/kernel/smp.c | |
3 | * | |
39ce010d | 4 | * Copyright IBM Corp. 1999,2007 |
1da177e4 | 5 | * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), |
39ce010d HC |
6 | * Martin Schwidefsky (schwidefsky@de.ibm.com) |
7 | * Heiko Carstens (heiko.carstens@de.ibm.com) | |
1da177e4 | 8 | * |
39ce010d | 9 | * based on other smp stuff by |
1da177e4 LT |
10 | * (c) 1995 Alan Cox, CymruNET Ltd <alan@cymru.net> |
11 | * (c) 1998 Ingo Molnar | |
12 | * | |
13 | * We work with logical cpu numbering everywhere we can. The only | |
14 | * functions using the real cpu address (got from STAP) are the sigp | |
15 | * functions. For all other functions we use the identity mapping. | |
16 | * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is | |
17 | * used e.g. to find the idle task belonging to a logical cpu. Every array | |
18 | * in the kernel is sorted by the logical cpu number and not by the physical | |
19 | * one which is causing all the confusion with __cpu_logical_map and | |
20 | * cpu_number_map in other architectures. | |
21 | */ | |
22 | ||
23 | #include <linux/module.h> | |
24 | #include <linux/init.h> | |
1da177e4 | 25 | #include <linux/mm.h> |
4e950f6f | 26 | #include <linux/err.h> |
1da177e4 LT |
27 | #include <linux/spinlock.h> |
28 | #include <linux/kernel_stat.h> | |
1da177e4 LT |
29 | #include <linux/delay.h> |
30 | #include <linux/cache.h> | |
31 | #include <linux/interrupt.h> | |
32 | #include <linux/cpu.h> | |
2b67fc46 | 33 | #include <linux/timex.h> |
411ed322 | 34 | #include <linux/bootmem.h> |
46b05d26 | 35 | #include <asm/ipl.h> |
2b67fc46 | 36 | #include <asm/setup.h> |
1da177e4 LT |
37 | #include <asm/sigp.h> |
38 | #include <asm/pgalloc.h> | |
39 | #include <asm/irq.h> | |
40 | #include <asm/s390_ext.h> | |
41 | #include <asm/cpcmd.h> | |
42 | #include <asm/tlbflush.h> | |
2b67fc46 | 43 | #include <asm/timer.h> |
411ed322 | 44 | #include <asm/lowcore.h> |
08d07968 | 45 | #include <asm/sclp.h> |
fae8b22d | 46 | #include <asm/cpu.h> |
1da177e4 | 47 | |
1da177e4 LT |
48 | /* |
49 | * An array with a pointer the lowcore of every CPU. | |
50 | */ | |
1da177e4 | 51 | struct _lowcore *lowcore_ptr[NR_CPUS]; |
39ce010d | 52 | EXPORT_SYMBOL(lowcore_ptr); |
1da177e4 | 53 | |
255acee7 | 54 | cpumask_t cpu_online_map = CPU_MASK_NONE; |
39ce010d HC |
55 | EXPORT_SYMBOL(cpu_online_map); |
56 | ||
48483b32 | 57 | cpumask_t cpu_possible_map = CPU_MASK_ALL; |
39ce010d | 58 | EXPORT_SYMBOL(cpu_possible_map); |
1da177e4 LT |
59 | |
60 | static struct task_struct *current_set[NR_CPUS]; | |
61 | ||
08d07968 HC |
62 | static u8 smp_cpu_type; |
63 | static int smp_use_sigp_detection; | |
64 | ||
65 | enum s390_cpu_state { | |
66 | CPU_STATE_STANDBY, | |
67 | CPU_STATE_CONFIGURED, | |
68 | }; | |
69 | ||
70 | #ifdef CONFIG_HOTPLUG_CPU | |
71 | static DEFINE_MUTEX(smp_cpu_state_mutex); | |
72 | #endif | |
73 | static int smp_cpu_state[NR_CPUS]; | |
74 | ||
75 | static DEFINE_PER_CPU(struct cpu, cpu_devices); | |
76 | DEFINE_PER_CPU(struct s390_idle_data, s390_idle); | |
77 | ||
1da177e4 | 78 | static void smp_ext_bitcall(int, ec_bit_sig); |
1da177e4 LT |
79 | |
80 | /* | |
63db6e8d JG |
81 | * Structure and data for __smp_call_function_map(). This is designed to |
82 | * minimise static memory requirements. It also looks cleaner. | |
1da177e4 LT |
83 | */ |
84 | static DEFINE_SPINLOCK(call_lock); | |
85 | ||
86 | struct call_data_struct { | |
87 | void (*func) (void *info); | |
88 | void *info; | |
63db6e8d JG |
89 | cpumask_t started; |
90 | cpumask_t finished; | |
1da177e4 LT |
91 | int wait; |
92 | }; | |
93 | ||
39ce010d | 94 | static struct call_data_struct *call_data; |
1da177e4 LT |
95 | |
96 | /* | |
97 | * 'Call function' interrupt callback | |
98 | */ | |
99 | static void do_call_function(void) | |
100 | { | |
101 | void (*func) (void *info) = call_data->func; | |
102 | void *info = call_data->info; | |
103 | int wait = call_data->wait; | |
104 | ||
63db6e8d | 105 | cpu_set(smp_processor_id(), call_data->started); |
1da177e4 LT |
106 | (*func)(info); |
107 | if (wait) | |
63db6e8d | 108 | cpu_set(smp_processor_id(), call_data->finished);; |
1da177e4 LT |
109 | } |
110 | ||
63db6e8d JG |
111 | static void __smp_call_function_map(void (*func) (void *info), void *info, |
112 | int nonatomic, int wait, cpumask_t map) | |
1da177e4 LT |
113 | { |
114 | struct call_data_struct data; | |
63db6e8d | 115 | int cpu, local = 0; |
1da177e4 | 116 | |
63db6e8d | 117 | /* |
25864162 | 118 | * Can deadlock when interrupts are disabled or if in wrong context. |
63db6e8d | 119 | */ |
25864162 | 120 | WARN_ON(irqs_disabled() || in_irq()); |
1da177e4 | 121 | |
63db6e8d JG |
122 | /* |
123 | * Check for local function call. We have to have the same call order | |
124 | * as in on_each_cpu() because of machine_restart_smp(). | |
125 | */ | |
126 | if (cpu_isset(smp_processor_id(), map)) { | |
127 | local = 1; | |
128 | cpu_clear(smp_processor_id(), map); | |
129 | } | |
130 | ||
131 | cpus_and(map, map, cpu_online_map); | |
132 | if (cpus_empty(map)) | |
133 | goto out; | |
1da177e4 LT |
134 | |
135 | data.func = func; | |
136 | data.info = info; | |
63db6e8d | 137 | data.started = CPU_MASK_NONE; |
1da177e4 LT |
138 | data.wait = wait; |
139 | if (wait) | |
63db6e8d | 140 | data.finished = CPU_MASK_NONE; |
1da177e4 | 141 | |
8da1aecd | 142 | spin_lock(&call_lock); |
1da177e4 | 143 | call_data = &data; |
63db6e8d JG |
144 | |
145 | for_each_cpu_mask(cpu, map) | |
146 | smp_ext_bitcall(cpu, ec_call_function); | |
1da177e4 LT |
147 | |
148 | /* Wait for response */ | |
63db6e8d | 149 | while (!cpus_equal(map, data.started)) |
1da177e4 | 150 | cpu_relax(); |
1da177e4 | 151 | if (wait) |
63db6e8d | 152 | while (!cpus_equal(map, data.finished)) |
1da177e4 | 153 | cpu_relax(); |
8da1aecd | 154 | spin_unlock(&call_lock); |
63db6e8d | 155 | out: |
8da1aecd HC |
156 | if (local) { |
157 | local_irq_disable(); | |
63db6e8d | 158 | func(info); |
8da1aecd HC |
159 | local_irq_enable(); |
160 | } | |
1da177e4 LT |
161 | } |
162 | ||
163 | /* | |
63db6e8d JG |
164 | * smp_call_function: |
165 | * @func: the function to run; this must be fast and non-blocking | |
166 | * @info: an arbitrary pointer to pass to the function | |
167 | * @nonatomic: unused | |
168 | * @wait: if true, wait (atomically) until function has completed on other CPUs | |
1da177e4 | 169 | * |
63db6e8d | 170 | * Run a function on all other CPUs. |
1da177e4 | 171 | * |
39ce010d HC |
172 | * You must not call this function with disabled interrupts, from a |
173 | * hardware interrupt handler or from a bottom half. | |
1da177e4 | 174 | */ |
63db6e8d JG |
175 | int smp_call_function(void (*func) (void *info), void *info, int nonatomic, |
176 | int wait) | |
1da177e4 | 177 | { |
63db6e8d | 178 | cpumask_t map; |
1da177e4 | 179 | |
25864162 | 180 | preempt_disable(); |
63db6e8d JG |
181 | map = cpu_online_map; |
182 | cpu_clear(smp_processor_id(), map); | |
183 | __smp_call_function_map(func, info, nonatomic, wait, map); | |
25864162 | 184 | preempt_enable(); |
63db6e8d JG |
185 | return 0; |
186 | } | |
187 | EXPORT_SYMBOL(smp_call_function); | |
1da177e4 | 188 | |
63db6e8d | 189 | /* |
3bb447fc HC |
190 | * smp_call_function_single: |
191 | * @cpu: the CPU where func should run | |
63db6e8d JG |
192 | * @func: the function to run; this must be fast and non-blocking |
193 | * @info: an arbitrary pointer to pass to the function | |
194 | * @nonatomic: unused | |
195 | * @wait: if true, wait (atomically) until function has completed on other CPUs | |
63db6e8d JG |
196 | * |
197 | * Run a function on one processor. | |
198 | * | |
39ce010d HC |
199 | * You must not call this function with disabled interrupts, from a |
200 | * hardware interrupt handler or from a bottom half. | |
63db6e8d | 201 | */ |
3bb447fc HC |
202 | int smp_call_function_single(int cpu, void (*func) (void *info), void *info, |
203 | int nonatomic, int wait) | |
63db6e8d | 204 | { |
25864162 | 205 | preempt_disable(); |
3bb447fc HC |
206 | __smp_call_function_map(func, info, nonatomic, wait, |
207 | cpumask_of_cpu(cpu)); | |
25864162 | 208 | preempt_enable(); |
1da177e4 LT |
209 | return 0; |
210 | } | |
3bb447fc | 211 | EXPORT_SYMBOL(smp_call_function_single); |
1da177e4 | 212 | |
677d7623 | 213 | void smp_send_stop(void) |
1da177e4 | 214 | { |
39ce010d | 215 | int cpu, rc; |
1da177e4 | 216 | |
677d7623 HC |
217 | /* Disable all interrupts/machine checks */ |
218 | __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK); | |
1da177e4 | 219 | |
677d7623 HC |
220 | /* write magic number to zero page (absolute 0) */ |
221 | lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC; | |
1da177e4 | 222 | |
677d7623 | 223 | /* stop all processors */ |
1da177e4 LT |
224 | for_each_online_cpu(cpu) { |
225 | if (cpu == smp_processor_id()) | |
226 | continue; | |
227 | do { | |
677d7623 | 228 | rc = signal_processor(cpu, sigp_stop); |
39ce010d | 229 | } while (rc == sigp_busy); |
1da177e4 | 230 | |
39ce010d | 231 | while (!smp_cpu_not_running(cpu)) |
c6b5b847 HC |
232 | cpu_relax(); |
233 | } | |
234 | } | |
235 | ||
1da177e4 LT |
236 | /* |
237 | * Reboot, halt and power_off routines for SMP. | |
238 | */ | |
39ce010d | 239 | void machine_restart_smp(char *__unused) |
1da177e4 | 240 | { |
c6b5b847 HC |
241 | smp_send_stop(); |
242 | do_reipl(); | |
1da177e4 LT |
243 | } |
244 | ||
245 | void machine_halt_smp(void) | |
246 | { | |
c6b5b847 HC |
247 | smp_send_stop(); |
248 | if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0) | |
249 | __cpcmd(vmhalt_cmd, NULL, 0, NULL); | |
250 | signal_processor(smp_processor_id(), sigp_stop_and_store_status); | |
251 | for (;;); | |
1da177e4 LT |
252 | } |
253 | ||
254 | void machine_power_off_smp(void) | |
255 | { | |
c6b5b847 HC |
256 | smp_send_stop(); |
257 | if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0) | |
258 | __cpcmd(vmpoff_cmd, NULL, 0, NULL); | |
259 | signal_processor(smp_processor_id(), sigp_stop_and_store_status); | |
260 | for (;;); | |
1da177e4 LT |
261 | } |
262 | ||
263 | /* | |
264 | * This is the main routine where commands issued by other | |
265 | * cpus are handled. | |
266 | */ | |
267 | ||
2b67fc46 | 268 | static void do_ext_call_interrupt(__u16 code) |
1da177e4 | 269 | { |
39ce010d | 270 | unsigned long bits; |
1da177e4 | 271 | |
39ce010d HC |
272 | /* |
273 | * handle bit signal external calls | |
274 | * | |
275 | * For the ec_schedule signal we have to do nothing. All the work | |
276 | * is done automatically when we return from the interrupt. | |
277 | */ | |
1da177e4 LT |
278 | bits = xchg(&S390_lowcore.ext_call_fast, 0); |
279 | ||
39ce010d | 280 | if (test_bit(ec_call_function, &bits)) |
1da177e4 LT |
281 | do_call_function(); |
282 | } | |
283 | ||
284 | /* | |
285 | * Send an external call sigp to another cpu and return without waiting | |
286 | * for its completion. | |
287 | */ | |
288 | static void smp_ext_bitcall(int cpu, ec_bit_sig sig) | |
289 | { | |
39ce010d HC |
290 | /* |
291 | * Set signaling bit in lowcore of target cpu and kick it | |
292 | */ | |
1da177e4 | 293 | set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast); |
39ce010d | 294 | while (signal_processor(cpu, sigp_emergency_signal) == sigp_busy) |
1da177e4 LT |
295 | udelay(10); |
296 | } | |
297 | ||
347a8dc3 | 298 | #ifndef CONFIG_64BIT |
1da177e4 LT |
299 | /* |
300 | * this function sends a 'purge tlb' signal to another CPU. | |
301 | */ | |
302 | void smp_ptlb_callback(void *info) | |
303 | { | |
ba8a9229 | 304 | __tlb_flush_local(); |
1da177e4 LT |
305 | } |
306 | ||
307 | void smp_ptlb_all(void) | |
308 | { | |
39ce010d | 309 | on_each_cpu(smp_ptlb_callback, NULL, 0, 1); |
1da177e4 LT |
310 | } |
311 | EXPORT_SYMBOL(smp_ptlb_all); | |
347a8dc3 | 312 | #endif /* ! CONFIG_64BIT */ |
1da177e4 LT |
313 | |
314 | /* | |
315 | * this function sends a 'reschedule' IPI to another CPU. | |
316 | * it goes straight through and wastes no time serializing | |
317 | * anything. Worst case is that we lose a reschedule ... | |
318 | */ | |
319 | void smp_send_reschedule(int cpu) | |
320 | { | |
39ce010d | 321 | smp_ext_bitcall(cpu, ec_schedule); |
1da177e4 LT |
322 | } |
323 | ||
324 | /* | |
325 | * parameter area for the set/clear control bit callbacks | |
326 | */ | |
94c12cc7 | 327 | struct ec_creg_mask_parms { |
1da177e4 LT |
328 | unsigned long orvals[16]; |
329 | unsigned long andvals[16]; | |
94c12cc7 | 330 | }; |
1da177e4 LT |
331 | |
332 | /* | |
333 | * callback for setting/clearing control bits | |
334 | */ | |
39ce010d HC |
335 | static void smp_ctl_bit_callback(void *info) |
336 | { | |
94c12cc7 | 337 | struct ec_creg_mask_parms *pp = info; |
1da177e4 LT |
338 | unsigned long cregs[16]; |
339 | int i; | |
39ce010d | 340 | |
94c12cc7 MS |
341 | __ctl_store(cregs, 0, 15); |
342 | for (i = 0; i <= 15; i++) | |
1da177e4 | 343 | cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i]; |
94c12cc7 | 344 | __ctl_load(cregs, 0, 15); |
1da177e4 LT |
345 | } |
346 | ||
347 | /* | |
348 | * Set a bit in a control register of all cpus | |
349 | */ | |
94c12cc7 MS |
350 | void smp_ctl_set_bit(int cr, int bit) |
351 | { | |
352 | struct ec_creg_mask_parms parms; | |
1da177e4 | 353 | |
94c12cc7 MS |
354 | memset(&parms.orvals, 0, sizeof(parms.orvals)); |
355 | memset(&parms.andvals, 0xff, sizeof(parms.andvals)); | |
1da177e4 | 356 | parms.orvals[cr] = 1 << bit; |
94c12cc7 | 357 | on_each_cpu(smp_ctl_bit_callback, &parms, 0, 1); |
1da177e4 | 358 | } |
39ce010d | 359 | EXPORT_SYMBOL(smp_ctl_set_bit); |
1da177e4 LT |
360 | |
361 | /* | |
362 | * Clear a bit in a control register of all cpus | |
363 | */ | |
94c12cc7 MS |
364 | void smp_ctl_clear_bit(int cr, int bit) |
365 | { | |
366 | struct ec_creg_mask_parms parms; | |
1da177e4 | 367 | |
94c12cc7 MS |
368 | memset(&parms.orvals, 0, sizeof(parms.orvals)); |
369 | memset(&parms.andvals, 0xff, sizeof(parms.andvals)); | |
1da177e4 | 370 | parms.andvals[cr] = ~(1L << bit); |
94c12cc7 | 371 | on_each_cpu(smp_ctl_bit_callback, &parms, 0, 1); |
1da177e4 | 372 | } |
39ce010d | 373 | EXPORT_SYMBOL(smp_ctl_clear_bit); |
1da177e4 | 374 | |
08d07968 HC |
375 | /* |
376 | * In early ipl state a temp. logically cpu number is needed, so the sigp | |
377 | * functions can be used to sense other cpus. Since NR_CPUS is >= 2 on | |
378 | * CONFIG_SMP and the ipl cpu is logical cpu 0, it must be 1. | |
379 | */ | |
380 | #define CPU_INIT_NO 1 | |
381 | ||
411ed322 MH |
382 | #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE) |
383 | ||
384 | /* | |
385 | * zfcpdump_prefix_array holds prefix registers for the following scenario: | |
386 | * 64 bit zfcpdump kernel and 31 bit kernel which is to be dumped. We have to | |
387 | * save its prefix registers, since they get lost, when switching from 31 bit | |
388 | * to 64 bit. | |
389 | */ | |
390 | unsigned int zfcpdump_prefix_array[NR_CPUS + 1] \ | |
391 | __attribute__((__section__(".data"))); | |
392 | ||
285f6722 | 393 | static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) |
411ed322 | 394 | { |
411ed322 MH |
395 | if (ipl_info.type != IPL_TYPE_FCP_DUMP) |
396 | return; | |
285f6722 HC |
397 | if (cpu >= NR_CPUS) { |
398 | printk(KERN_WARNING "Registers for cpu %i not saved since dump " | |
399 | "kernel was compiled with NR_CPUS=%i\n", cpu, NR_CPUS); | |
400 | return; | |
411ed322 | 401 | } |
48483b32 | 402 | zfcpdump_save_areas[cpu] = kmalloc(sizeof(union save_area), GFP_KERNEL); |
08d07968 HC |
403 | __cpu_logical_map[CPU_INIT_NO] = (__u16) phy_cpu; |
404 | while (signal_processor(CPU_INIT_NO, sigp_stop_and_store_status) == | |
405 | sigp_busy) | |
285f6722 HC |
406 | cpu_relax(); |
407 | memcpy(zfcpdump_save_areas[cpu], | |
408 | (void *)(unsigned long) store_prefix() + SAVE_AREA_BASE, | |
409 | SAVE_AREA_SIZE); | |
410 | #ifdef CONFIG_64BIT | |
411 | /* copy original prefix register */ | |
412 | zfcpdump_save_areas[cpu]->s390x.pref_reg = zfcpdump_prefix_array[cpu]; | |
413 | #endif | |
411ed322 MH |
414 | } |
415 | ||
416 | union save_area *zfcpdump_save_areas[NR_CPUS + 1]; | |
417 | EXPORT_SYMBOL_GPL(zfcpdump_save_areas); | |
418 | ||
419 | #else | |
285f6722 HC |
420 | |
421 | static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { } | |
422 | ||
423 | #endif /* CONFIG_ZFCPDUMP || CONFIG_ZFCPDUMP_MODULE */ | |
411ed322 | 424 | |
08d07968 HC |
425 | static int cpu_stopped(int cpu) |
426 | { | |
427 | __u32 status; | |
428 | ||
429 | /* Check for stopped state */ | |
430 | if (signal_processor_ps(&status, 0, cpu, sigp_sense) == | |
431 | sigp_status_stored) { | |
432 | if (status & 0x40) | |
433 | return 1; | |
434 | } | |
435 | return 0; | |
436 | } | |
437 | ||
08d07968 HC |
438 | static int cpu_known(int cpu_id) |
439 | { | |
440 | int cpu; | |
441 | ||
442 | for_each_present_cpu(cpu) { | |
443 | if (__cpu_logical_map[cpu] == cpu_id) | |
444 | return 1; | |
445 | } | |
446 | return 0; | |
447 | } | |
448 | ||
449 | static int smp_rescan_cpus_sigp(cpumask_t avail) | |
450 | { | |
451 | int cpu_id, logical_cpu; | |
452 | ||
453 | logical_cpu = first_cpu(avail); | |
454 | if (logical_cpu == NR_CPUS) | |
455 | return 0; | |
456 | for (cpu_id = 0; cpu_id <= 65535; cpu_id++) { | |
457 | if (cpu_known(cpu_id)) | |
458 | continue; | |
459 | __cpu_logical_map[logical_cpu] = cpu_id; | |
460 | if (!cpu_stopped(logical_cpu)) | |
461 | continue; | |
462 | cpu_set(logical_cpu, cpu_present_map); | |
463 | smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; | |
464 | logical_cpu = next_cpu(logical_cpu, avail); | |
465 | if (logical_cpu == NR_CPUS) | |
466 | break; | |
467 | } | |
468 | return 0; | |
469 | } | |
470 | ||
48483b32 | 471 | static int smp_rescan_cpus_sclp(cpumask_t avail) |
08d07968 HC |
472 | { |
473 | struct sclp_cpu_info *info; | |
474 | int cpu_id, logical_cpu, cpu; | |
475 | int rc; | |
476 | ||
477 | logical_cpu = first_cpu(avail); | |
478 | if (logical_cpu == NR_CPUS) | |
479 | return 0; | |
48483b32 | 480 | info = kmalloc(sizeof(*info), GFP_KERNEL); |
08d07968 HC |
481 | if (!info) |
482 | return -ENOMEM; | |
483 | rc = sclp_get_cpu_info(info); | |
484 | if (rc) | |
485 | goto out; | |
486 | for (cpu = 0; cpu < info->combined; cpu++) { | |
487 | if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) | |
488 | continue; | |
489 | cpu_id = info->cpu[cpu].address; | |
490 | if (cpu_known(cpu_id)) | |
491 | continue; | |
492 | __cpu_logical_map[logical_cpu] = cpu_id; | |
493 | cpu_set(logical_cpu, cpu_present_map); | |
494 | if (cpu >= info->configured) | |
495 | smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY; | |
496 | else | |
497 | smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED; | |
498 | logical_cpu = next_cpu(logical_cpu, avail); | |
499 | if (logical_cpu == NR_CPUS) | |
500 | break; | |
501 | } | |
502 | out: | |
48483b32 | 503 | kfree(info); |
08d07968 HC |
504 | return rc; |
505 | } | |
506 | ||
507 | static int smp_rescan_cpus(void) | |
508 | { | |
509 | cpumask_t avail; | |
510 | ||
48483b32 | 511 | cpus_xor(avail, cpu_possible_map, cpu_present_map); |
08d07968 HC |
512 | if (smp_use_sigp_detection) |
513 | return smp_rescan_cpus_sigp(avail); | |
514 | else | |
515 | return smp_rescan_cpus_sclp(avail); | |
1da177e4 LT |
516 | } |
517 | ||
48483b32 HC |
518 | static void __init smp_detect_cpus(void) |
519 | { | |
520 | unsigned int cpu, c_cpus, s_cpus; | |
521 | struct sclp_cpu_info *info; | |
522 | u16 boot_cpu_addr, cpu_addr; | |
523 | ||
524 | c_cpus = 1; | |
525 | s_cpus = 0; | |
526 | boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr; | |
527 | info = kmalloc(sizeof(*info), GFP_KERNEL); | |
528 | if (!info) | |
529 | panic("smp_detect_cpus failed to allocate memory\n"); | |
530 | /* Use sigp detection algorithm if sclp doesn't work. */ | |
531 | if (sclp_get_cpu_info(info)) { | |
532 | smp_use_sigp_detection = 1; | |
533 | for (cpu = 0; cpu <= 65535; cpu++) { | |
534 | if (cpu == boot_cpu_addr) | |
535 | continue; | |
536 | __cpu_logical_map[CPU_INIT_NO] = cpu; | |
537 | if (!cpu_stopped(CPU_INIT_NO)) | |
538 | continue; | |
539 | smp_get_save_area(c_cpus, cpu); | |
540 | c_cpus++; | |
541 | } | |
542 | goto out; | |
543 | } | |
544 | ||
545 | if (info->has_cpu_type) { | |
546 | for (cpu = 0; cpu < info->combined; cpu++) { | |
547 | if (info->cpu[cpu].address == boot_cpu_addr) { | |
548 | smp_cpu_type = info->cpu[cpu].type; | |
549 | break; | |
550 | } | |
551 | } | |
552 | } | |
553 | ||
554 | for (cpu = 0; cpu < info->combined; cpu++) { | |
555 | if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type) | |
556 | continue; | |
557 | cpu_addr = info->cpu[cpu].address; | |
558 | if (cpu_addr == boot_cpu_addr) | |
559 | continue; | |
560 | __cpu_logical_map[CPU_INIT_NO] = cpu_addr; | |
561 | if (!cpu_stopped(CPU_INIT_NO)) { | |
562 | s_cpus++; | |
563 | continue; | |
564 | } | |
565 | smp_get_save_area(c_cpus, cpu_addr); | |
566 | c_cpus++; | |
567 | } | |
568 | out: | |
569 | kfree(info); | |
570 | printk(KERN_INFO "CPUs: %d configured, %d standby\n", c_cpus, s_cpus); | |
571 | lock_cpu_hotplug(); | |
572 | smp_rescan_cpus(); | |
573 | unlock_cpu_hotplug(); | |
574 | } | |
575 | ||
1da177e4 | 576 | /* |
39ce010d | 577 | * Activate a secondary processor. |
1da177e4 | 578 | */ |
ea1f4eec | 579 | int __cpuinit start_secondary(void *cpuvoid) |
1da177e4 | 580 | { |
39ce010d HC |
581 | /* Setup the cpu */ |
582 | cpu_init(); | |
5bfb5d69 | 583 | preempt_disable(); |
d54853ef | 584 | /* Enable TOD clock interrupts on the secondary cpu. */ |
39ce010d | 585 | init_cpu_timer(); |
1da177e4 | 586 | #ifdef CONFIG_VIRT_TIMER |
d54853ef | 587 | /* Enable cpu timer interrupts on the secondary cpu. */ |
39ce010d | 588 | init_cpu_vtimer(); |
1da177e4 | 589 | #endif |
1da177e4 | 590 | /* Enable pfault pseudo page faults on this cpu. */ |
29b08d2b HC |
591 | pfault_init(); |
592 | ||
1da177e4 LT |
593 | /* Mark this cpu as online */ |
594 | cpu_set(smp_processor_id(), cpu_online_map); | |
595 | /* Switch on interrupts */ | |
596 | local_irq_enable(); | |
39ce010d HC |
597 | /* Print info about this processor */ |
598 | print_cpu_info(&S390_lowcore.cpu_data); | |
599 | /* cpu_idle will call schedule for us */ | |
600 | cpu_idle(); | |
601 | return 0; | |
1da177e4 LT |
602 | } |
603 | ||
604 | static void __init smp_create_idle(unsigned int cpu) | |
605 | { | |
606 | struct task_struct *p; | |
607 | ||
608 | /* | |
609 | * don't care about the psw and regs settings since we'll never | |
610 | * reschedule the forked task. | |
611 | */ | |
612 | p = fork_idle(cpu); | |
613 | if (IS_ERR(p)) | |
614 | panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p)); | |
615 | current_set[cpu] = p; | |
fae8b22d | 616 | spin_lock_init(&(&per_cpu(s390_idle, cpu))->lock); |
1da177e4 LT |
617 | } |
618 | ||
1da177e4 | 619 | /* Upping and downing of CPUs */ |
39ce010d | 620 | int __cpu_up(unsigned int cpu) |
1da177e4 LT |
621 | { |
622 | struct task_struct *idle; | |
39ce010d | 623 | struct _lowcore *cpu_lowcore; |
1da177e4 | 624 | struct stack_frame *sf; |
39ce010d | 625 | sigp_ccode ccode; |
1da177e4 | 626 | |
08d07968 HC |
627 | if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED) |
628 | return -EIO; | |
1da177e4 LT |
629 | |
630 | ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]), | |
631 | cpu, sigp_set_prefix); | |
39ce010d | 632 | if (ccode) { |
1da177e4 LT |
633 | printk("sigp_set_prefix failed for cpu %d " |
634 | "with condition code %d\n", | |
635 | (int) cpu, (int) ccode); | |
636 | return -EIO; | |
637 | } | |
638 | ||
639 | idle = current_set[cpu]; | |
39ce010d | 640 | cpu_lowcore = lowcore_ptr[cpu]; |
1da177e4 | 641 | cpu_lowcore->kernel_stack = (unsigned long) |
39ce010d | 642 | task_stack_page(idle) + THREAD_SIZE; |
1da177e4 LT |
643 | sf = (struct stack_frame *) (cpu_lowcore->kernel_stack |
644 | - sizeof(struct pt_regs) | |
645 | - sizeof(struct stack_frame)); | |
646 | memset(sf, 0, sizeof(struct stack_frame)); | |
647 | sf->gprs[9] = (unsigned long) sf; | |
648 | cpu_lowcore->save_area[15] = (unsigned long) sf; | |
649 | __ctl_store(cpu_lowcore->cregs_save_area[0], 0, 15); | |
94c12cc7 MS |
650 | asm volatile( |
651 | " stam 0,15,0(%0)" | |
652 | : : "a" (&cpu_lowcore->access_regs_save_area) : "memory"); | |
1da177e4 | 653 | cpu_lowcore->percpu_offset = __per_cpu_offset[cpu]; |
39ce010d HC |
654 | cpu_lowcore->current_task = (unsigned long) idle; |
655 | cpu_lowcore->cpu_data.cpu_nr = cpu; | |
1da177e4 | 656 | eieio(); |
699ff13f | 657 | |
39ce010d | 658 | while (signal_processor(cpu, sigp_restart) == sigp_busy) |
699ff13f | 659 | udelay(10); |
1da177e4 LT |
660 | |
661 | while (!cpu_online(cpu)) | |
662 | cpu_relax(); | |
663 | return 0; | |
664 | } | |
665 | ||
48483b32 | 666 | static int __init setup_possible_cpus(char *s) |
255acee7 | 667 | { |
48483b32 | 668 | int pcpus, cpu; |
255acee7 | 669 | |
48483b32 HC |
670 | pcpus = simple_strtoul(s, NULL, 0); |
671 | cpu_possible_map = cpumask_of_cpu(0); | |
672 | for (cpu = 1; cpu < pcpus && cpu < NR_CPUS; cpu++) | |
255acee7 | 673 | cpu_set(cpu, cpu_possible_map); |
37a33026 HC |
674 | return 0; |
675 | } | |
676 | early_param("possible_cpus", setup_possible_cpus); | |
677 | ||
48483b32 HC |
678 | #ifdef CONFIG_HOTPLUG_CPU |
679 | ||
39ce010d | 680 | int __cpu_disable(void) |
1da177e4 | 681 | { |
94c12cc7 | 682 | struct ec_creg_mask_parms cr_parms; |
f3705136 | 683 | int cpu = smp_processor_id(); |
1da177e4 | 684 | |
f3705136 | 685 | cpu_clear(cpu, cpu_online_map); |
1da177e4 | 686 | |
1da177e4 | 687 | /* Disable pfault pseudo page faults on this cpu. */ |
29b08d2b | 688 | pfault_fini(); |
1da177e4 | 689 | |
94c12cc7 MS |
690 | memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals)); |
691 | memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals)); | |
1da177e4 | 692 | |
94c12cc7 | 693 | /* disable all external interrupts */ |
1da177e4 | 694 | cr_parms.orvals[0] = 0; |
39ce010d HC |
695 | cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 | |
696 | 1 << 11 | 1 << 10 | 1 << 6 | 1 << 4); | |
1da177e4 | 697 | /* disable all I/O interrupts */ |
1da177e4 | 698 | cr_parms.orvals[6] = 0; |
39ce010d HC |
699 | cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 | |
700 | 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24); | |
1da177e4 | 701 | /* disable most machine checks */ |
1da177e4 | 702 | cr_parms.orvals[14] = 0; |
39ce010d HC |
703 | cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 | |
704 | 1 << 25 | 1 << 24); | |
94c12cc7 | 705 | |
1da177e4 LT |
706 | smp_ctl_bit_callback(&cr_parms); |
707 | ||
1da177e4 LT |
708 | return 0; |
709 | } | |
710 | ||
39ce010d | 711 | void __cpu_die(unsigned int cpu) |
1da177e4 LT |
712 | { |
713 | /* Wait until target cpu is down */ | |
714 | while (!smp_cpu_not_running(cpu)) | |
715 | cpu_relax(); | |
08d07968 | 716 | printk(KERN_INFO "Processor %d spun down\n", cpu); |
1da177e4 LT |
717 | } |
718 | ||
39ce010d | 719 | void cpu_die(void) |
1da177e4 LT |
720 | { |
721 | idle_task_exit(); | |
722 | signal_processor(smp_processor_id(), sigp_stop); | |
723 | BUG(); | |
39ce010d | 724 | for (;;); |
1da177e4 LT |
725 | } |
726 | ||
255acee7 HC |
727 | #endif /* CONFIG_HOTPLUG_CPU */ |
728 | ||
1da177e4 LT |
729 | /* |
730 | * Cycle through the processors and setup structures. | |
731 | */ | |
732 | ||
733 | void __init smp_prepare_cpus(unsigned int max_cpus) | |
734 | { | |
735 | unsigned long stack; | |
736 | unsigned int cpu; | |
39ce010d HC |
737 | int i; |
738 | ||
48483b32 HC |
739 | smp_detect_cpus(); |
740 | ||
39ce010d HC |
741 | /* request the 0x1201 emergency signal external interrupt */ |
742 | if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0) | |
743 | panic("Couldn't request external interrupt 0x1201"); | |
744 | memset(lowcore_ptr, 0, sizeof(lowcore_ptr)); | |
745 | /* | |
746 | * Initialize prefix pages and stacks for all possible cpus | |
747 | */ | |
1da177e4 LT |
748 | print_cpu_info(&S390_lowcore.cpu_data); |
749 | ||
39ce010d | 750 | for_each_possible_cpu(i) { |
1da177e4 | 751 | lowcore_ptr[i] = (struct _lowcore *) |
39ce010d HC |
752 | __get_free_pages(GFP_KERNEL | GFP_DMA, |
753 | sizeof(void*) == 8 ? 1 : 0); | |
754 | stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER); | |
755 | if (!lowcore_ptr[i] || !stack) | |
1da177e4 LT |
756 | panic("smp_boot_cpus failed to allocate memory\n"); |
757 | ||
758 | *(lowcore_ptr[i]) = S390_lowcore; | |
39ce010d HC |
759 | lowcore_ptr[i]->async_stack = stack + ASYNC_SIZE; |
760 | stack = __get_free_pages(GFP_KERNEL, 0); | |
761 | if (!stack) | |
1da177e4 | 762 | panic("smp_boot_cpus failed to allocate memory\n"); |
39ce010d | 763 | lowcore_ptr[i]->panic_stack = stack + PAGE_SIZE; |
347a8dc3 | 764 | #ifndef CONFIG_64BIT |
77fa2245 HC |
765 | if (MACHINE_HAS_IEEE) { |
766 | lowcore_ptr[i]->extended_save_area_addr = | |
39ce010d HC |
767 | (__u32) __get_free_pages(GFP_KERNEL, 0); |
768 | if (!lowcore_ptr[i]->extended_save_area_addr) | |
77fa2245 HC |
769 | panic("smp_boot_cpus failed to " |
770 | "allocate memory\n"); | |
771 | } | |
1da177e4 LT |
772 | #endif |
773 | } | |
347a8dc3 | 774 | #ifndef CONFIG_64BIT |
77fa2245 HC |
775 | if (MACHINE_HAS_IEEE) |
776 | ctl_set_bit(14, 29); /* enable extended save area */ | |
777 | #endif | |
1da177e4 LT |
778 | set_prefix((u32)(unsigned long) lowcore_ptr[smp_processor_id()]); |
779 | ||
97db7fbf | 780 | for_each_possible_cpu(cpu) |
1da177e4 LT |
781 | if (cpu != smp_processor_id()) |
782 | smp_create_idle(cpu); | |
783 | } | |
784 | ||
ea1f4eec | 785 | void __init smp_prepare_boot_cpu(void) |
1da177e4 LT |
786 | { |
787 | BUG_ON(smp_processor_id() != 0); | |
788 | ||
48483b32 HC |
789 | current_thread_info()->cpu = 0; |
790 | cpu_set(0, cpu_present_map); | |
1da177e4 | 791 | cpu_set(0, cpu_online_map); |
1da177e4 LT |
792 | S390_lowcore.percpu_offset = __per_cpu_offset[0]; |
793 | current_set[0] = current; | |
08d07968 | 794 | smp_cpu_state[0] = CPU_STATE_CONFIGURED; |
fae8b22d | 795 | spin_lock_init(&(&__get_cpu_var(s390_idle))->lock); |
1da177e4 LT |
796 | } |
797 | ||
ea1f4eec | 798 | void __init smp_cpus_done(unsigned int max_cpus) |
1da177e4 | 799 | { |
1da177e4 LT |
800 | } |
801 | ||
802 | /* | |
803 | * the frequency of the profiling timer can be changed | |
804 | * by writing a multiplier value into /proc/profile. | |
805 | * | |
806 | * usually you want to run this on all CPUs ;) | |
807 | */ | |
808 | int setup_profiling_timer(unsigned int multiplier) | |
809 | { | |
39ce010d | 810 | return 0; |
1da177e4 LT |
811 | } |
812 | ||
08d07968 HC |
813 | #ifdef CONFIG_HOTPLUG_CPU |
814 | static ssize_t cpu_configure_show(struct sys_device *dev, char *buf) | |
815 | { | |
816 | ssize_t count; | |
817 | ||
818 | mutex_lock(&smp_cpu_state_mutex); | |
819 | count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]); | |
820 | mutex_unlock(&smp_cpu_state_mutex); | |
821 | return count; | |
822 | } | |
823 | ||
824 | static ssize_t cpu_configure_store(struct sys_device *dev, const char *buf, | |
825 | size_t count) | |
826 | { | |
827 | int cpu = dev->id; | |
828 | int val, rc; | |
829 | char delim; | |
830 | ||
831 | if (sscanf(buf, "%d %c", &val, &delim) != 1) | |
832 | return -EINVAL; | |
833 | if (val != 0 && val != 1) | |
834 | return -EINVAL; | |
835 | ||
836 | mutex_lock(&smp_cpu_state_mutex); | |
837 | lock_cpu_hotplug(); | |
838 | rc = -EBUSY; | |
839 | if (cpu_online(cpu)) | |
840 | goto out; | |
841 | rc = 0; | |
842 | switch (val) { | |
843 | case 0: | |
844 | if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) { | |
845 | rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]); | |
846 | if (!rc) | |
847 | smp_cpu_state[cpu] = CPU_STATE_STANDBY; | |
848 | } | |
849 | break; | |
850 | case 1: | |
851 | if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) { | |
852 | rc = sclp_cpu_configure(__cpu_logical_map[cpu]); | |
853 | if (!rc) | |
854 | smp_cpu_state[cpu] = CPU_STATE_CONFIGURED; | |
855 | } | |
856 | break; | |
857 | default: | |
858 | break; | |
859 | } | |
860 | out: | |
861 | unlock_cpu_hotplug(); | |
862 | mutex_unlock(&smp_cpu_state_mutex); | |
863 | return rc ? rc : count; | |
864 | } | |
865 | static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store); | |
866 | #endif /* CONFIG_HOTPLUG_CPU */ | |
867 | ||
868 | static ssize_t show_cpu_address(struct sys_device *dev, char *buf) | |
869 | { | |
870 | return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]); | |
871 | } | |
872 | static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL); | |
873 | ||
874 | ||
875 | static struct attribute *cpu_common_attrs[] = { | |
876 | #ifdef CONFIG_HOTPLUG_CPU | |
877 | &attr_configure.attr, | |
878 | #endif | |
879 | &attr_address.attr, | |
880 | NULL, | |
881 | }; | |
882 | ||
883 | static struct attribute_group cpu_common_attr_group = { | |
884 | .attrs = cpu_common_attrs, | |
885 | }; | |
1da177e4 | 886 | |
2fc2d1e9 HC |
887 | static ssize_t show_capability(struct sys_device *dev, char *buf) |
888 | { | |
889 | unsigned int capability; | |
890 | int rc; | |
891 | ||
892 | rc = get_cpu_capability(&capability); | |
893 | if (rc) | |
894 | return rc; | |
895 | return sprintf(buf, "%u\n", capability); | |
896 | } | |
897 | static SYSDEV_ATTR(capability, 0444, show_capability, NULL); | |
898 | ||
fae8b22d HC |
899 | static ssize_t show_idle_count(struct sys_device *dev, char *buf) |
900 | { | |
901 | struct s390_idle_data *idle; | |
902 | unsigned long long idle_count; | |
903 | ||
904 | idle = &per_cpu(s390_idle, dev->id); | |
905 | spin_lock_irq(&idle->lock); | |
906 | idle_count = idle->idle_count; | |
907 | spin_unlock_irq(&idle->lock); | |
908 | return sprintf(buf, "%llu\n", idle_count); | |
909 | } | |
910 | static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL); | |
911 | ||
912 | static ssize_t show_idle_time(struct sys_device *dev, char *buf) | |
913 | { | |
914 | struct s390_idle_data *idle; | |
915 | unsigned long long new_time; | |
916 | ||
917 | idle = &per_cpu(s390_idle, dev->id); | |
918 | spin_lock_irq(&idle->lock); | |
919 | if (idle->in_idle) { | |
920 | new_time = get_clock(); | |
921 | idle->idle_time += new_time - idle->idle_enter; | |
922 | idle->idle_enter = new_time; | |
923 | } | |
924 | new_time = idle->idle_time; | |
925 | spin_unlock_irq(&idle->lock); | |
69d39d66 | 926 | return sprintf(buf, "%llu\n", new_time >> 12); |
fae8b22d | 927 | } |
69d39d66 | 928 | static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL); |
fae8b22d | 929 | |
08d07968 | 930 | static struct attribute *cpu_online_attrs[] = { |
fae8b22d HC |
931 | &attr_capability.attr, |
932 | &attr_idle_count.attr, | |
69d39d66 | 933 | &attr_idle_time_us.attr, |
fae8b22d HC |
934 | NULL, |
935 | }; | |
936 | ||
08d07968 HC |
937 | static struct attribute_group cpu_online_attr_group = { |
938 | .attrs = cpu_online_attrs, | |
fae8b22d HC |
939 | }; |
940 | ||
2fc2d1e9 HC |
941 | static int __cpuinit smp_cpu_notify(struct notifier_block *self, |
942 | unsigned long action, void *hcpu) | |
943 | { | |
944 | unsigned int cpu = (unsigned int)(long)hcpu; | |
945 | struct cpu *c = &per_cpu(cpu_devices, cpu); | |
946 | struct sys_device *s = &c->sysdev; | |
fae8b22d | 947 | struct s390_idle_data *idle; |
2fc2d1e9 HC |
948 | |
949 | switch (action) { | |
950 | case CPU_ONLINE: | |
8bb78442 | 951 | case CPU_ONLINE_FROZEN: |
fae8b22d HC |
952 | idle = &per_cpu(s390_idle, cpu); |
953 | spin_lock_irq(&idle->lock); | |
954 | idle->idle_enter = 0; | |
955 | idle->idle_time = 0; | |
956 | idle->idle_count = 0; | |
957 | spin_unlock_irq(&idle->lock); | |
08d07968 | 958 | if (sysfs_create_group(&s->kobj, &cpu_online_attr_group)) |
2fc2d1e9 HC |
959 | return NOTIFY_BAD; |
960 | break; | |
961 | case CPU_DEAD: | |
8bb78442 | 962 | case CPU_DEAD_FROZEN: |
08d07968 | 963 | sysfs_remove_group(&s->kobj, &cpu_online_attr_group); |
2fc2d1e9 HC |
964 | break; |
965 | } | |
966 | return NOTIFY_OK; | |
967 | } | |
968 | ||
969 | static struct notifier_block __cpuinitdata smp_cpu_nb = { | |
39ce010d | 970 | .notifier_call = smp_cpu_notify, |
2fc2d1e9 HC |
971 | }; |
972 | ||
08d07968 HC |
973 | static int smp_add_present_cpu(int cpu) |
974 | { | |
975 | struct cpu *c = &per_cpu(cpu_devices, cpu); | |
976 | struct sys_device *s = &c->sysdev; | |
977 | int rc; | |
978 | ||
979 | c->hotpluggable = 1; | |
980 | rc = register_cpu(c, cpu); | |
981 | if (rc) | |
982 | goto out; | |
983 | rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group); | |
984 | if (rc) | |
985 | goto out_cpu; | |
986 | if (!cpu_online(cpu)) | |
987 | goto out; | |
988 | rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group); | |
989 | if (!rc) | |
990 | return 0; | |
991 | sysfs_remove_group(&s->kobj, &cpu_common_attr_group); | |
992 | out_cpu: | |
993 | #ifdef CONFIG_HOTPLUG_CPU | |
994 | unregister_cpu(c); | |
995 | #endif | |
996 | out: | |
997 | return rc; | |
998 | } | |
999 | ||
1000 | #ifdef CONFIG_HOTPLUG_CPU | |
1001 | static ssize_t rescan_store(struct sys_device *dev, const char *buf, | |
1002 | size_t count) | |
1003 | { | |
1004 | cpumask_t newcpus; | |
1005 | int cpu; | |
1006 | int rc; | |
1007 | ||
1008 | mutex_lock(&smp_cpu_state_mutex); | |
1009 | lock_cpu_hotplug(); | |
1010 | newcpus = cpu_present_map; | |
1011 | rc = smp_rescan_cpus(); | |
1012 | if (rc) | |
1013 | goto out; | |
1014 | cpus_andnot(newcpus, cpu_present_map, newcpus); | |
1015 | for_each_cpu_mask(cpu, newcpus) { | |
1016 | rc = smp_add_present_cpu(cpu); | |
1017 | if (rc) | |
1018 | cpu_clear(cpu, cpu_present_map); | |
1019 | } | |
1020 | rc = 0; | |
1021 | out: | |
1022 | unlock_cpu_hotplug(); | |
1023 | mutex_unlock(&smp_cpu_state_mutex); | |
1024 | return rc ? rc : count; | |
1025 | } | |
1026 | static SYSDEV_ATTR(rescan, 0200, NULL, rescan_store); | |
1027 | #endif /* CONFIG_HOTPLUG_CPU */ | |
1028 | ||
1da177e4 LT |
1029 | static int __init topology_init(void) |
1030 | { | |
1031 | int cpu; | |
fae8b22d | 1032 | int rc; |
2fc2d1e9 HC |
1033 | |
1034 | register_cpu_notifier(&smp_cpu_nb); | |
1da177e4 | 1035 | |
08d07968 HC |
1036 | #ifdef CONFIG_HOTPLUG_CPU |
1037 | rc = sysfs_create_file(&cpu_sysdev_class.kset.kobj, | |
1038 | &attr_rescan.attr); | |
1039 | if (rc) | |
1040 | return rc; | |
1041 | #endif | |
1042 | for_each_present_cpu(cpu) { | |
1043 | rc = smp_add_present_cpu(cpu); | |
fae8b22d HC |
1044 | if (rc) |
1045 | return rc; | |
1da177e4 LT |
1046 | } |
1047 | return 0; | |
1048 | } | |
1da177e4 | 1049 | subsys_initcall(topology_init); |