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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Implement CPU time clocks for the POSIX clock interface. | |
3 | */ | |
4 | ||
5 | #include <linux/sched.h> | |
6 | #include <linux/posix-timers.h> | |
1da177e4 | 7 | #include <linux/errno.h> |
f8bd2258 RZ |
8 | #include <linux/math64.h> |
9 | #include <asm/uaccess.h> | |
bb34d92f | 10 | #include <linux/kernel_stat.h> |
3f0a525e | 11 | #include <trace/events/timer.h> |
1da177e4 | 12 | |
f06febc9 | 13 | /* |
f55db609 SG |
14 | * Called after updating RLIMIT_CPU to run cpu timer and update |
15 | * tsk->signal->cputime_expires expiration cache if necessary. Needs | |
16 | * siglock protection since other code may update expiration cache as | |
17 | * well. | |
f06febc9 FM |
18 | */ |
19 | void update_rlimit_cpu(unsigned long rlim_new) | |
20 | { | |
42c4ab41 | 21 | cputime_t cputime = secs_to_cputime(rlim_new); |
f06febc9 | 22 | |
f55db609 SG |
23 | spin_lock_irq(¤t->sighand->siglock); |
24 | set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); | |
25 | spin_unlock_irq(¤t->sighand->siglock); | |
f06febc9 FM |
26 | } |
27 | ||
a924b04d | 28 | static int check_clock(const clockid_t which_clock) |
1da177e4 LT |
29 | { |
30 | int error = 0; | |
31 | struct task_struct *p; | |
32 | const pid_t pid = CPUCLOCK_PID(which_clock); | |
33 | ||
34 | if (CPUCLOCK_WHICH(which_clock) >= CPUCLOCK_MAX) | |
35 | return -EINVAL; | |
36 | ||
37 | if (pid == 0) | |
38 | return 0; | |
39 | ||
40 | read_lock(&tasklist_lock); | |
8dc86af0 | 41 | p = find_task_by_vpid(pid); |
bac0abd6 PE |
42 | if (!p || !(CPUCLOCK_PERTHREAD(which_clock) ? |
43 | same_thread_group(p, current) : thread_group_leader(p))) { | |
1da177e4 LT |
44 | error = -EINVAL; |
45 | } | |
46 | read_unlock(&tasklist_lock); | |
47 | ||
48 | return error; | |
49 | } | |
50 | ||
51 | static inline union cpu_time_count | |
a924b04d | 52 | timespec_to_sample(const clockid_t which_clock, const struct timespec *tp) |
1da177e4 LT |
53 | { |
54 | union cpu_time_count ret; | |
55 | ret.sched = 0; /* high half always zero when .cpu used */ | |
56 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
ee500f27 | 57 | ret.sched = (unsigned long long)tp->tv_sec * NSEC_PER_SEC + tp->tv_nsec; |
1da177e4 LT |
58 | } else { |
59 | ret.cpu = timespec_to_cputime(tp); | |
60 | } | |
61 | return ret; | |
62 | } | |
63 | ||
a924b04d | 64 | static void sample_to_timespec(const clockid_t which_clock, |
1da177e4 LT |
65 | union cpu_time_count cpu, |
66 | struct timespec *tp) | |
67 | { | |
f8bd2258 RZ |
68 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) |
69 | *tp = ns_to_timespec(cpu.sched); | |
70 | else | |
1da177e4 | 71 | cputime_to_timespec(cpu.cpu, tp); |
1da177e4 LT |
72 | } |
73 | ||
a924b04d | 74 | static inline int cpu_time_before(const clockid_t which_clock, |
1da177e4 LT |
75 | union cpu_time_count now, |
76 | union cpu_time_count then) | |
77 | { | |
78 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
79 | return now.sched < then.sched; | |
80 | } else { | |
81 | return cputime_lt(now.cpu, then.cpu); | |
82 | } | |
83 | } | |
a924b04d | 84 | static inline void cpu_time_add(const clockid_t which_clock, |
1da177e4 LT |
85 | union cpu_time_count *acc, |
86 | union cpu_time_count val) | |
87 | { | |
88 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
89 | acc->sched += val.sched; | |
90 | } else { | |
91 | acc->cpu = cputime_add(acc->cpu, val.cpu); | |
92 | } | |
93 | } | |
a924b04d | 94 | static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock, |
1da177e4 LT |
95 | union cpu_time_count a, |
96 | union cpu_time_count b) | |
97 | { | |
98 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
99 | a.sched -= b.sched; | |
100 | } else { | |
101 | a.cpu = cputime_sub(a.cpu, b.cpu); | |
102 | } | |
103 | return a; | |
104 | } | |
105 | ||
ac08c264 TG |
106 | /* |
107 | * Divide and limit the result to res >= 1 | |
108 | * | |
109 | * This is necessary to prevent signal delivery starvation, when the result of | |
110 | * the division would be rounded down to 0. | |
111 | */ | |
112 | static inline cputime_t cputime_div_non_zero(cputime_t time, unsigned long div) | |
113 | { | |
114 | cputime_t res = cputime_div(time, div); | |
115 | ||
116 | return max_t(cputime_t, res, 1); | |
117 | } | |
118 | ||
1da177e4 LT |
119 | /* |
120 | * Update expiry time from increment, and increase overrun count, | |
121 | * given the current clock sample. | |
122 | */ | |
7a4ed937 | 123 | static void bump_cpu_timer(struct k_itimer *timer, |
1da177e4 LT |
124 | union cpu_time_count now) |
125 | { | |
126 | int i; | |
127 | ||
128 | if (timer->it.cpu.incr.sched == 0) | |
129 | return; | |
130 | ||
131 | if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) { | |
132 | unsigned long long delta, incr; | |
133 | ||
134 | if (now.sched < timer->it.cpu.expires.sched) | |
135 | return; | |
136 | incr = timer->it.cpu.incr.sched; | |
137 | delta = now.sched + incr - timer->it.cpu.expires.sched; | |
138 | /* Don't use (incr*2 < delta), incr*2 might overflow. */ | |
139 | for (i = 0; incr < delta - incr; i++) | |
140 | incr = incr << 1; | |
141 | for (; i >= 0; incr >>= 1, i--) { | |
7a4ed937 | 142 | if (delta < incr) |
1da177e4 LT |
143 | continue; |
144 | timer->it.cpu.expires.sched += incr; | |
145 | timer->it_overrun += 1 << i; | |
146 | delta -= incr; | |
147 | } | |
148 | } else { | |
149 | cputime_t delta, incr; | |
150 | ||
151 | if (cputime_lt(now.cpu, timer->it.cpu.expires.cpu)) | |
152 | return; | |
153 | incr = timer->it.cpu.incr.cpu; | |
154 | delta = cputime_sub(cputime_add(now.cpu, incr), | |
155 | timer->it.cpu.expires.cpu); | |
156 | /* Don't use (incr*2 < delta), incr*2 might overflow. */ | |
157 | for (i = 0; cputime_lt(incr, cputime_sub(delta, incr)); i++) | |
158 | incr = cputime_add(incr, incr); | |
159 | for (; i >= 0; incr = cputime_halve(incr), i--) { | |
7a4ed937 | 160 | if (cputime_lt(delta, incr)) |
1da177e4 LT |
161 | continue; |
162 | timer->it.cpu.expires.cpu = | |
163 | cputime_add(timer->it.cpu.expires.cpu, incr); | |
164 | timer->it_overrun += 1 << i; | |
165 | delta = cputime_sub(delta, incr); | |
166 | } | |
167 | } | |
168 | } | |
169 | ||
170 | static inline cputime_t prof_ticks(struct task_struct *p) | |
171 | { | |
172 | return cputime_add(p->utime, p->stime); | |
173 | } | |
174 | static inline cputime_t virt_ticks(struct task_struct *p) | |
175 | { | |
176 | return p->utime; | |
177 | } | |
1da177e4 | 178 | |
a924b04d | 179 | int posix_cpu_clock_getres(const clockid_t which_clock, struct timespec *tp) |
1da177e4 LT |
180 | { |
181 | int error = check_clock(which_clock); | |
182 | if (!error) { | |
183 | tp->tv_sec = 0; | |
184 | tp->tv_nsec = ((NSEC_PER_SEC + HZ - 1) / HZ); | |
185 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
186 | /* | |
187 | * If sched_clock is using a cycle counter, we | |
188 | * don't have any idea of its true resolution | |
189 | * exported, but it is much more than 1s/HZ. | |
190 | */ | |
191 | tp->tv_nsec = 1; | |
192 | } | |
193 | } | |
194 | return error; | |
195 | } | |
196 | ||
a924b04d | 197 | int posix_cpu_clock_set(const clockid_t which_clock, const struct timespec *tp) |
1da177e4 LT |
198 | { |
199 | /* | |
200 | * You can never reset a CPU clock, but we check for other errors | |
201 | * in the call before failing with EPERM. | |
202 | */ | |
203 | int error = check_clock(which_clock); | |
204 | if (error == 0) { | |
205 | error = -EPERM; | |
206 | } | |
207 | return error; | |
208 | } | |
209 | ||
210 | ||
211 | /* | |
212 | * Sample a per-thread clock for the given task. | |
213 | */ | |
a924b04d | 214 | static int cpu_clock_sample(const clockid_t which_clock, struct task_struct *p, |
1da177e4 LT |
215 | union cpu_time_count *cpu) |
216 | { | |
217 | switch (CPUCLOCK_WHICH(which_clock)) { | |
218 | default: | |
219 | return -EINVAL; | |
220 | case CPUCLOCK_PROF: | |
221 | cpu->cpu = prof_ticks(p); | |
222 | break; | |
223 | case CPUCLOCK_VIRT: | |
224 | cpu->cpu = virt_ticks(p); | |
225 | break; | |
226 | case CPUCLOCK_SCHED: | |
c5f8d995 | 227 | cpu->sched = task_sched_runtime(p); |
1da177e4 LT |
228 | break; |
229 | } | |
230 | return 0; | |
231 | } | |
232 | ||
4cd4c1b4 PZ |
233 | void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times) |
234 | { | |
235 | struct sighand_struct *sighand; | |
236 | struct signal_struct *sig; | |
237 | struct task_struct *t; | |
238 | ||
239 | *times = INIT_CPUTIME; | |
240 | ||
241 | rcu_read_lock(); | |
242 | sighand = rcu_dereference(tsk->sighand); | |
243 | if (!sighand) | |
244 | goto out; | |
245 | ||
246 | sig = tsk->signal; | |
247 | ||
248 | t = tsk; | |
249 | do { | |
250 | times->utime = cputime_add(times->utime, t->utime); | |
251 | times->stime = cputime_add(times->stime, t->stime); | |
252 | times->sum_exec_runtime += t->se.sum_exec_runtime; | |
253 | ||
254 | t = next_thread(t); | |
255 | } while (t != tsk); | |
256 | ||
257 | times->utime = cputime_add(times->utime, sig->utime); | |
258 | times->stime = cputime_add(times->stime, sig->stime); | |
259 | times->sum_exec_runtime += sig->sum_sched_runtime; | |
260 | out: | |
261 | rcu_read_unlock(); | |
262 | } | |
263 | ||
4da94d49 PZ |
264 | static void update_gt_cputime(struct task_cputime *a, struct task_cputime *b) |
265 | { | |
266 | if (cputime_gt(b->utime, a->utime)) | |
267 | a->utime = b->utime; | |
268 | ||
269 | if (cputime_gt(b->stime, a->stime)) | |
270 | a->stime = b->stime; | |
271 | ||
272 | if (b->sum_exec_runtime > a->sum_exec_runtime) | |
273 | a->sum_exec_runtime = b->sum_exec_runtime; | |
274 | } | |
275 | ||
276 | void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times) | |
277 | { | |
278 | struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; | |
279 | struct task_cputime sum; | |
280 | unsigned long flags; | |
281 | ||
282 | spin_lock_irqsave(&cputimer->lock, flags); | |
283 | if (!cputimer->running) { | |
284 | cputimer->running = 1; | |
285 | /* | |
286 | * The POSIX timer interface allows for absolute time expiry | |
287 | * values through the TIMER_ABSTIME flag, therefore we have | |
288 | * to synchronize the timer to the clock every time we start | |
289 | * it. | |
290 | */ | |
291 | thread_group_cputime(tsk, &sum); | |
292 | update_gt_cputime(&cputimer->cputime, &sum); | |
293 | } | |
294 | *times = cputimer->cputime; | |
295 | spin_unlock_irqrestore(&cputimer->lock, flags); | |
296 | } | |
297 | ||
1da177e4 LT |
298 | /* |
299 | * Sample a process (thread group) clock for the given group_leader task. | |
300 | * Must be called with tasklist_lock held for reading. | |
1da177e4 | 301 | */ |
bb34d92f FM |
302 | static int cpu_clock_sample_group(const clockid_t which_clock, |
303 | struct task_struct *p, | |
304 | union cpu_time_count *cpu) | |
1da177e4 | 305 | { |
f06febc9 FM |
306 | struct task_cputime cputime; |
307 | ||
eccdaeaf | 308 | switch (CPUCLOCK_WHICH(which_clock)) { |
1da177e4 LT |
309 | default: |
310 | return -EINVAL; | |
311 | case CPUCLOCK_PROF: | |
c5f8d995 | 312 | thread_group_cputime(p, &cputime); |
f06febc9 | 313 | cpu->cpu = cputime_add(cputime.utime, cputime.stime); |
1da177e4 LT |
314 | break; |
315 | case CPUCLOCK_VIRT: | |
c5f8d995 | 316 | thread_group_cputime(p, &cputime); |
f06febc9 | 317 | cpu->cpu = cputime.utime; |
1da177e4 LT |
318 | break; |
319 | case CPUCLOCK_SCHED: | |
c5f8d995 | 320 | cpu->sched = thread_group_sched_runtime(p); |
1da177e4 LT |
321 | break; |
322 | } | |
323 | return 0; | |
324 | } | |
325 | ||
1da177e4 | 326 | |
a924b04d | 327 | int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) |
1da177e4 LT |
328 | { |
329 | const pid_t pid = CPUCLOCK_PID(which_clock); | |
330 | int error = -EINVAL; | |
331 | union cpu_time_count rtn; | |
332 | ||
333 | if (pid == 0) { | |
334 | /* | |
335 | * Special case constant value for our own clocks. | |
336 | * We don't have to do any lookup to find ourselves. | |
337 | */ | |
338 | if (CPUCLOCK_PERTHREAD(which_clock)) { | |
339 | /* | |
340 | * Sampling just ourselves we can do with no locking. | |
341 | */ | |
342 | error = cpu_clock_sample(which_clock, | |
343 | current, &rtn); | |
344 | } else { | |
345 | read_lock(&tasklist_lock); | |
346 | error = cpu_clock_sample_group(which_clock, | |
347 | current, &rtn); | |
348 | read_unlock(&tasklist_lock); | |
349 | } | |
350 | } else { | |
351 | /* | |
352 | * Find the given PID, and validate that the caller | |
353 | * should be able to see it. | |
354 | */ | |
355 | struct task_struct *p; | |
1f2ea083 | 356 | rcu_read_lock(); |
8dc86af0 | 357 | p = find_task_by_vpid(pid); |
1da177e4 LT |
358 | if (p) { |
359 | if (CPUCLOCK_PERTHREAD(which_clock)) { | |
bac0abd6 | 360 | if (same_thread_group(p, current)) { |
1da177e4 LT |
361 | error = cpu_clock_sample(which_clock, |
362 | p, &rtn); | |
363 | } | |
1f2ea083 PM |
364 | } else { |
365 | read_lock(&tasklist_lock); | |
bac0abd6 | 366 | if (thread_group_leader(p) && p->signal) { |
1f2ea083 PM |
367 | error = |
368 | cpu_clock_sample_group(which_clock, | |
369 | p, &rtn); | |
370 | } | |
371 | read_unlock(&tasklist_lock); | |
1da177e4 LT |
372 | } |
373 | } | |
1f2ea083 | 374 | rcu_read_unlock(); |
1da177e4 LT |
375 | } |
376 | ||
377 | if (error) | |
378 | return error; | |
379 | sample_to_timespec(which_clock, rtn, tp); | |
380 | return 0; | |
381 | } | |
382 | ||
383 | ||
384 | /* | |
385 | * Validate the clockid_t for a new CPU-clock timer, and initialize the timer. | |
ba5ea951 SG |
386 | * This is called from sys_timer_create() and do_cpu_nanosleep() with the |
387 | * new timer already all-zeros initialized. | |
1da177e4 LT |
388 | */ |
389 | int posix_cpu_timer_create(struct k_itimer *new_timer) | |
390 | { | |
391 | int ret = 0; | |
392 | const pid_t pid = CPUCLOCK_PID(new_timer->it_clock); | |
393 | struct task_struct *p; | |
394 | ||
395 | if (CPUCLOCK_WHICH(new_timer->it_clock) >= CPUCLOCK_MAX) | |
396 | return -EINVAL; | |
397 | ||
398 | INIT_LIST_HEAD(&new_timer->it.cpu.entry); | |
1da177e4 LT |
399 | |
400 | read_lock(&tasklist_lock); | |
401 | if (CPUCLOCK_PERTHREAD(new_timer->it_clock)) { | |
402 | if (pid == 0) { | |
403 | p = current; | |
404 | } else { | |
8dc86af0 | 405 | p = find_task_by_vpid(pid); |
bac0abd6 | 406 | if (p && !same_thread_group(p, current)) |
1da177e4 LT |
407 | p = NULL; |
408 | } | |
409 | } else { | |
410 | if (pid == 0) { | |
411 | p = current->group_leader; | |
412 | } else { | |
8dc86af0 | 413 | p = find_task_by_vpid(pid); |
bac0abd6 | 414 | if (p && !thread_group_leader(p)) |
1da177e4 LT |
415 | p = NULL; |
416 | } | |
417 | } | |
418 | new_timer->it.cpu.task = p; | |
419 | if (p) { | |
420 | get_task_struct(p); | |
421 | } else { | |
422 | ret = -EINVAL; | |
423 | } | |
424 | read_unlock(&tasklist_lock); | |
425 | ||
426 | return ret; | |
427 | } | |
428 | ||
429 | /* | |
430 | * Clean up a CPU-clock timer that is about to be destroyed. | |
431 | * This is called from timer deletion with the timer already locked. | |
432 | * If we return TIMER_RETRY, it's necessary to release the timer's lock | |
433 | * and try again. (This happens when the timer is in the middle of firing.) | |
434 | */ | |
435 | int posix_cpu_timer_del(struct k_itimer *timer) | |
436 | { | |
437 | struct task_struct *p = timer->it.cpu.task; | |
108150ea | 438 | int ret = 0; |
1da177e4 | 439 | |
108150ea | 440 | if (likely(p != NULL)) { |
9465bee8 LT |
441 | read_lock(&tasklist_lock); |
442 | if (unlikely(p->signal == NULL)) { | |
443 | /* | |
444 | * We raced with the reaping of the task. | |
445 | * The deletion should have cleared us off the list. | |
446 | */ | |
447 | BUG_ON(!list_empty(&timer->it.cpu.entry)); | |
448 | } else { | |
9465bee8 | 449 | spin_lock(&p->sighand->siglock); |
108150ea ON |
450 | if (timer->it.cpu.firing) |
451 | ret = TIMER_RETRY; | |
452 | else | |
453 | list_del(&timer->it.cpu.entry); | |
9465bee8 LT |
454 | spin_unlock(&p->sighand->siglock); |
455 | } | |
456 | read_unlock(&tasklist_lock); | |
108150ea ON |
457 | |
458 | if (!ret) | |
459 | put_task_struct(p); | |
1da177e4 | 460 | } |
1da177e4 | 461 | |
108150ea | 462 | return ret; |
1da177e4 LT |
463 | } |
464 | ||
465 | /* | |
466 | * Clean out CPU timers still ticking when a thread exited. The task | |
467 | * pointer is cleared, and the expiry time is replaced with the residual | |
468 | * time for later timer_gettime calls to return. | |
469 | * This must be called with the siglock held. | |
470 | */ | |
471 | static void cleanup_timers(struct list_head *head, | |
472 | cputime_t utime, cputime_t stime, | |
41b86e9c | 473 | unsigned long long sum_exec_runtime) |
1da177e4 LT |
474 | { |
475 | struct cpu_timer_list *timer, *next; | |
476 | cputime_t ptime = cputime_add(utime, stime); | |
477 | ||
478 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 LT |
479 | list_del_init(&timer->entry); |
480 | if (cputime_lt(timer->expires.cpu, ptime)) { | |
481 | timer->expires.cpu = cputime_zero; | |
482 | } else { | |
483 | timer->expires.cpu = cputime_sub(timer->expires.cpu, | |
484 | ptime); | |
485 | } | |
486 | } | |
487 | ||
488 | ++head; | |
489 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 LT |
490 | list_del_init(&timer->entry); |
491 | if (cputime_lt(timer->expires.cpu, utime)) { | |
492 | timer->expires.cpu = cputime_zero; | |
493 | } else { | |
494 | timer->expires.cpu = cputime_sub(timer->expires.cpu, | |
495 | utime); | |
496 | } | |
497 | } | |
498 | ||
499 | ++head; | |
500 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 | 501 | list_del_init(&timer->entry); |
41b86e9c | 502 | if (timer->expires.sched < sum_exec_runtime) { |
1da177e4 LT |
503 | timer->expires.sched = 0; |
504 | } else { | |
41b86e9c | 505 | timer->expires.sched -= sum_exec_runtime; |
1da177e4 LT |
506 | } |
507 | } | |
508 | } | |
509 | ||
510 | /* | |
511 | * These are both called with the siglock held, when the current thread | |
512 | * is being reaped. When the final (leader) thread in the group is reaped, | |
513 | * posix_cpu_timers_exit_group will be called after posix_cpu_timers_exit. | |
514 | */ | |
515 | void posix_cpu_timers_exit(struct task_struct *tsk) | |
516 | { | |
517 | cleanup_timers(tsk->cpu_timers, | |
41b86e9c | 518 | tsk->utime, tsk->stime, tsk->se.sum_exec_runtime); |
1da177e4 LT |
519 | |
520 | } | |
521 | void posix_cpu_timers_exit_group(struct task_struct *tsk) | |
522 | { | |
17d42c1c | 523 | struct signal_struct *const sig = tsk->signal; |
ca531a0a | 524 | |
f06febc9 | 525 | cleanup_timers(tsk->signal->cpu_timers, |
17d42c1c SG |
526 | cputime_add(tsk->utime, sig->utime), |
527 | cputime_add(tsk->stime, sig->stime), | |
528 | tsk->se.sum_exec_runtime + sig->sum_sched_runtime); | |
1da177e4 LT |
529 | } |
530 | ||
531 | static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) | |
532 | { | |
533 | /* | |
534 | * That's all for this thread or process. | |
535 | * We leave our residual in expires to be reported. | |
536 | */ | |
537 | put_task_struct(timer->it.cpu.task); | |
538 | timer->it.cpu.task = NULL; | |
539 | timer->it.cpu.expires = cpu_time_sub(timer->it_clock, | |
540 | timer->it.cpu.expires, | |
541 | now); | |
542 | } | |
543 | ||
d1e3b6d1 SG |
544 | static inline int expires_gt(cputime_t expires, cputime_t new_exp) |
545 | { | |
546 | return cputime_eq(expires, cputime_zero) || | |
547 | cputime_gt(expires, new_exp); | |
548 | } | |
549 | ||
550 | static inline int expires_le(cputime_t expires, cputime_t new_exp) | |
551 | { | |
552 | return !cputime_eq(expires, cputime_zero) && | |
553 | cputime_le(expires, new_exp); | |
554 | } | |
1da177e4 LT |
555 | /* |
556 | * Insert the timer on the appropriate list before any timers that | |
557 | * expire later. This must be called with the tasklist_lock held | |
558 | * for reading, and interrupts disabled. | |
559 | */ | |
560 | static void arm_timer(struct k_itimer *timer, union cpu_time_count now) | |
561 | { | |
562 | struct task_struct *p = timer->it.cpu.task; | |
563 | struct list_head *head, *listpos; | |
564 | struct cpu_timer_list *const nt = &timer->it.cpu; | |
565 | struct cpu_timer_list *next; | |
1da177e4 LT |
566 | |
567 | head = (CPUCLOCK_PERTHREAD(timer->it_clock) ? | |
568 | p->cpu_timers : p->signal->cpu_timers); | |
569 | head += CPUCLOCK_WHICH(timer->it_clock); | |
570 | ||
571 | BUG_ON(!irqs_disabled()); | |
572 | spin_lock(&p->sighand->siglock); | |
573 | ||
574 | listpos = head; | |
575 | if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) { | |
576 | list_for_each_entry(next, head, entry) { | |
70ab81c2 | 577 | if (next->expires.sched > nt->expires.sched) |
1da177e4 | 578 | break; |
70ab81c2 | 579 | listpos = &next->entry; |
1da177e4 LT |
580 | } |
581 | } else { | |
582 | list_for_each_entry(next, head, entry) { | |
70ab81c2 | 583 | if (cputime_gt(next->expires.cpu, nt->expires.cpu)) |
1da177e4 | 584 | break; |
70ab81c2 | 585 | listpos = &next->entry; |
1da177e4 LT |
586 | } |
587 | } | |
588 | list_add(&nt->entry, listpos); | |
589 | ||
590 | if (listpos == head) { | |
591 | /* | |
592 | * We are the new earliest-expiring timer. | |
593 | * If we are a thread timer, there can always | |
594 | * be a process timer telling us to stop earlier. | |
595 | */ | |
596 | ||
597 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
d1e3b6d1 SG |
598 | union cpu_time_count *exp = &nt->expires; |
599 | ||
1da177e4 LT |
600 | switch (CPUCLOCK_WHICH(timer->it_clock)) { |
601 | default: | |
602 | BUG(); | |
603 | case CPUCLOCK_PROF: | |
d1e3b6d1 SG |
604 | if (expires_gt(p->cputime_expires.prof_exp, |
605 | exp->cpu)) | |
606 | p->cputime_expires.prof_exp = exp->cpu; | |
1da177e4 LT |
607 | break; |
608 | case CPUCLOCK_VIRT: | |
d1e3b6d1 SG |
609 | if (expires_gt(p->cputime_expires.virt_exp, |
610 | exp->cpu)) | |
611 | p->cputime_expires.virt_exp = exp->cpu; | |
1da177e4 LT |
612 | break; |
613 | case CPUCLOCK_SCHED: | |
f06febc9 | 614 | if (p->cputime_expires.sched_exp == 0 || |
d1e3b6d1 | 615 | p->cputime_expires.sched_exp > exp->sched) |
f06febc9 | 616 | p->cputime_expires.sched_exp = |
d1e3b6d1 | 617 | exp->sched; |
1da177e4 LT |
618 | break; |
619 | } | |
620 | } else { | |
42c4ab41 SG |
621 | struct signal_struct *const sig = p->signal; |
622 | union cpu_time_count *exp = &timer->it.cpu.expires; | |
623 | ||
1da177e4 | 624 | /* |
f06febc9 | 625 | * For a process timer, set the cached expiration time. |
1da177e4 LT |
626 | */ |
627 | switch (CPUCLOCK_WHICH(timer->it_clock)) { | |
628 | default: | |
629 | BUG(); | |
630 | case CPUCLOCK_VIRT: | |
f55db609 SG |
631 | if (expires_gt(sig->cputime_expires.virt_exp, exp->cpu)) |
632 | sig->cputime_expires.virt_exp = exp->cpu; | |
1da177e4 | 633 | case CPUCLOCK_PROF: |
f55db609 SG |
634 | if (expires_gt(sig->cputime_expires.prof_exp, exp->cpu)) |
635 | sig->cputime_expires.prof_exp = exp->cpu; | |
f06febc9 | 636 | break; |
1da177e4 | 637 | case CPUCLOCK_SCHED: |
42c4ab41 | 638 | sig->cputime_expires.sched_exp = exp->sched; |
1da177e4 LT |
639 | break; |
640 | } | |
641 | } | |
642 | } | |
643 | ||
644 | spin_unlock(&p->sighand->siglock); | |
645 | } | |
646 | ||
647 | /* | |
648 | * The timer is locked, fire it and arrange for its reload. | |
649 | */ | |
650 | static void cpu_timer_fire(struct k_itimer *timer) | |
651 | { | |
652 | if (unlikely(timer->sigq == NULL)) { | |
653 | /* | |
654 | * This a special case for clock_nanosleep, | |
655 | * not a normal timer from sys_timer_create. | |
656 | */ | |
657 | wake_up_process(timer->it_process); | |
658 | timer->it.cpu.expires.sched = 0; | |
659 | } else if (timer->it.cpu.incr.sched == 0) { | |
660 | /* | |
661 | * One-shot timer. Clear it as soon as it's fired. | |
662 | */ | |
663 | posix_timer_event(timer, 0); | |
664 | timer->it.cpu.expires.sched = 0; | |
665 | } else if (posix_timer_event(timer, ++timer->it_requeue_pending)) { | |
666 | /* | |
667 | * The signal did not get queued because the signal | |
668 | * was ignored, so we won't get any callback to | |
669 | * reload the timer. But we need to keep it | |
670 | * ticking in case the signal is deliverable next time. | |
671 | */ | |
672 | posix_cpu_timer_schedule(timer); | |
673 | } | |
674 | } | |
675 | ||
3997ad31 PZ |
676 | /* |
677 | * Sample a process (thread group) timer for the given group_leader task. | |
678 | * Must be called with tasklist_lock held for reading. | |
679 | */ | |
680 | static int cpu_timer_sample_group(const clockid_t which_clock, | |
681 | struct task_struct *p, | |
682 | union cpu_time_count *cpu) | |
683 | { | |
684 | struct task_cputime cputime; | |
685 | ||
686 | thread_group_cputimer(p, &cputime); | |
687 | switch (CPUCLOCK_WHICH(which_clock)) { | |
688 | default: | |
689 | return -EINVAL; | |
690 | case CPUCLOCK_PROF: | |
691 | cpu->cpu = cputime_add(cputime.utime, cputime.stime); | |
692 | break; | |
693 | case CPUCLOCK_VIRT: | |
694 | cpu->cpu = cputime.utime; | |
695 | break; | |
696 | case CPUCLOCK_SCHED: | |
697 | cpu->sched = cputime.sum_exec_runtime + task_delta_exec(p); | |
698 | break; | |
699 | } | |
700 | return 0; | |
701 | } | |
702 | ||
1da177e4 LT |
703 | /* |
704 | * Guts of sys_timer_settime for CPU timers. | |
705 | * This is called with the timer locked and interrupts disabled. | |
706 | * If we return TIMER_RETRY, it's necessary to release the timer's lock | |
707 | * and try again. (This happens when the timer is in the middle of firing.) | |
708 | */ | |
709 | int posix_cpu_timer_set(struct k_itimer *timer, int flags, | |
710 | struct itimerspec *new, struct itimerspec *old) | |
711 | { | |
712 | struct task_struct *p = timer->it.cpu.task; | |
713 | union cpu_time_count old_expires, new_expires, val; | |
714 | int ret; | |
715 | ||
716 | if (unlikely(p == NULL)) { | |
717 | /* | |
718 | * Timer refers to a dead task's clock. | |
719 | */ | |
720 | return -ESRCH; | |
721 | } | |
722 | ||
723 | new_expires = timespec_to_sample(timer->it_clock, &new->it_value); | |
724 | ||
725 | read_lock(&tasklist_lock); | |
726 | /* | |
727 | * We need the tasklist_lock to protect against reaping that | |
728 | * clears p->signal. If p has just been reaped, we can no | |
729 | * longer get any information about it at all. | |
730 | */ | |
731 | if (unlikely(p->signal == NULL)) { | |
732 | read_unlock(&tasklist_lock); | |
733 | put_task_struct(p); | |
734 | timer->it.cpu.task = NULL; | |
735 | return -ESRCH; | |
736 | } | |
737 | ||
738 | /* | |
739 | * Disarm any old timer after extracting its expiry time. | |
740 | */ | |
741 | BUG_ON(!irqs_disabled()); | |
a69ac4a7 ON |
742 | |
743 | ret = 0; | |
1da177e4 LT |
744 | spin_lock(&p->sighand->siglock); |
745 | old_expires = timer->it.cpu.expires; | |
a69ac4a7 ON |
746 | if (unlikely(timer->it.cpu.firing)) { |
747 | timer->it.cpu.firing = -1; | |
748 | ret = TIMER_RETRY; | |
749 | } else | |
750 | list_del_init(&timer->it.cpu.entry); | |
1da177e4 LT |
751 | spin_unlock(&p->sighand->siglock); |
752 | ||
753 | /* | |
754 | * We need to sample the current value to convert the new | |
755 | * value from to relative and absolute, and to convert the | |
756 | * old value from absolute to relative. To set a process | |
757 | * timer, we need a sample to balance the thread expiry | |
758 | * times (in arm_timer). With an absolute time, we must | |
759 | * check if it's already passed. In short, we need a sample. | |
760 | */ | |
761 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
762 | cpu_clock_sample(timer->it_clock, p, &val); | |
763 | } else { | |
3997ad31 | 764 | cpu_timer_sample_group(timer->it_clock, p, &val); |
1da177e4 LT |
765 | } |
766 | ||
767 | if (old) { | |
768 | if (old_expires.sched == 0) { | |
769 | old->it_value.tv_sec = 0; | |
770 | old->it_value.tv_nsec = 0; | |
771 | } else { | |
772 | /* | |
773 | * Update the timer in case it has | |
774 | * overrun already. If it has, | |
775 | * we'll report it as having overrun | |
776 | * and with the next reloaded timer | |
777 | * already ticking, though we are | |
778 | * swallowing that pending | |
779 | * notification here to install the | |
780 | * new setting. | |
781 | */ | |
782 | bump_cpu_timer(timer, val); | |
783 | if (cpu_time_before(timer->it_clock, val, | |
784 | timer->it.cpu.expires)) { | |
785 | old_expires = cpu_time_sub( | |
786 | timer->it_clock, | |
787 | timer->it.cpu.expires, val); | |
788 | sample_to_timespec(timer->it_clock, | |
789 | old_expires, | |
790 | &old->it_value); | |
791 | } else { | |
792 | old->it_value.tv_nsec = 1; | |
793 | old->it_value.tv_sec = 0; | |
794 | } | |
795 | } | |
796 | } | |
797 | ||
a69ac4a7 | 798 | if (unlikely(ret)) { |
1da177e4 LT |
799 | /* |
800 | * We are colliding with the timer actually firing. | |
801 | * Punt after filling in the timer's old value, and | |
802 | * disable this firing since we are already reporting | |
803 | * it as an overrun (thanks to bump_cpu_timer above). | |
804 | */ | |
805 | read_unlock(&tasklist_lock); | |
1da177e4 LT |
806 | goto out; |
807 | } | |
808 | ||
809 | if (new_expires.sched != 0 && !(flags & TIMER_ABSTIME)) { | |
810 | cpu_time_add(timer->it_clock, &new_expires, val); | |
811 | } | |
812 | ||
813 | /* | |
814 | * Install the new expiry time (or zero). | |
815 | * For a timer with no notification action, we don't actually | |
816 | * arm the timer (we'll just fake it for timer_gettime). | |
817 | */ | |
818 | timer->it.cpu.expires = new_expires; | |
819 | if (new_expires.sched != 0 && | |
820 | (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE && | |
821 | cpu_time_before(timer->it_clock, val, new_expires)) { | |
822 | arm_timer(timer, val); | |
823 | } | |
824 | ||
825 | read_unlock(&tasklist_lock); | |
826 | ||
827 | /* | |
828 | * Install the new reload setting, and | |
829 | * set up the signal and overrun bookkeeping. | |
830 | */ | |
831 | timer->it.cpu.incr = timespec_to_sample(timer->it_clock, | |
832 | &new->it_interval); | |
833 | ||
834 | /* | |
835 | * This acts as a modification timestamp for the timer, | |
836 | * so any automatic reload attempt will punt on seeing | |
837 | * that we have reset the timer manually. | |
838 | */ | |
839 | timer->it_requeue_pending = (timer->it_requeue_pending + 2) & | |
840 | ~REQUEUE_PENDING; | |
841 | timer->it_overrun_last = 0; | |
842 | timer->it_overrun = -1; | |
843 | ||
844 | if (new_expires.sched != 0 && | |
845 | (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE && | |
846 | !cpu_time_before(timer->it_clock, val, new_expires)) { | |
847 | /* | |
848 | * The designated time already passed, so we notify | |
849 | * immediately, even if the thread never runs to | |
850 | * accumulate more time on this clock. | |
851 | */ | |
852 | cpu_timer_fire(timer); | |
853 | } | |
854 | ||
855 | ret = 0; | |
856 | out: | |
857 | if (old) { | |
858 | sample_to_timespec(timer->it_clock, | |
859 | timer->it.cpu.incr, &old->it_interval); | |
860 | } | |
861 | return ret; | |
862 | } | |
863 | ||
864 | void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) | |
865 | { | |
866 | union cpu_time_count now; | |
867 | struct task_struct *p = timer->it.cpu.task; | |
868 | int clear_dead; | |
869 | ||
870 | /* | |
871 | * Easy part: convert the reload time. | |
872 | */ | |
873 | sample_to_timespec(timer->it_clock, | |
874 | timer->it.cpu.incr, &itp->it_interval); | |
875 | ||
876 | if (timer->it.cpu.expires.sched == 0) { /* Timer not armed at all. */ | |
877 | itp->it_value.tv_sec = itp->it_value.tv_nsec = 0; | |
878 | return; | |
879 | } | |
880 | ||
881 | if (unlikely(p == NULL)) { | |
882 | /* | |
883 | * This task already died and the timer will never fire. | |
884 | * In this case, expires is actually the dead value. | |
885 | */ | |
886 | dead: | |
887 | sample_to_timespec(timer->it_clock, timer->it.cpu.expires, | |
888 | &itp->it_value); | |
889 | return; | |
890 | } | |
891 | ||
892 | /* | |
893 | * Sample the clock to take the difference with the expiry time. | |
894 | */ | |
895 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
896 | cpu_clock_sample(timer->it_clock, p, &now); | |
897 | clear_dead = p->exit_state; | |
898 | } else { | |
899 | read_lock(&tasklist_lock); | |
900 | if (unlikely(p->signal == NULL)) { | |
901 | /* | |
902 | * The process has been reaped. | |
903 | * We can't even collect a sample any more. | |
904 | * Call the timer disarmed, nothing else to do. | |
905 | */ | |
906 | put_task_struct(p); | |
907 | timer->it.cpu.task = NULL; | |
908 | timer->it.cpu.expires.sched = 0; | |
909 | read_unlock(&tasklist_lock); | |
910 | goto dead; | |
911 | } else { | |
3997ad31 | 912 | cpu_timer_sample_group(timer->it_clock, p, &now); |
1da177e4 LT |
913 | clear_dead = (unlikely(p->exit_state) && |
914 | thread_group_empty(p)); | |
915 | } | |
916 | read_unlock(&tasklist_lock); | |
917 | } | |
918 | ||
919 | if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) { | |
920 | if (timer->it.cpu.incr.sched == 0 && | |
921 | cpu_time_before(timer->it_clock, | |
922 | timer->it.cpu.expires, now)) { | |
923 | /* | |
924 | * Do-nothing timer expired and has no reload, | |
925 | * so it's as if it was never set. | |
926 | */ | |
927 | timer->it.cpu.expires.sched = 0; | |
928 | itp->it_value.tv_sec = itp->it_value.tv_nsec = 0; | |
929 | return; | |
930 | } | |
931 | /* | |
932 | * Account for any expirations and reloads that should | |
933 | * have happened. | |
934 | */ | |
935 | bump_cpu_timer(timer, now); | |
936 | } | |
937 | ||
938 | if (unlikely(clear_dead)) { | |
939 | /* | |
940 | * We've noticed that the thread is dead, but | |
941 | * not yet reaped. Take this opportunity to | |
942 | * drop our task ref. | |
943 | */ | |
944 | clear_dead_task(timer, now); | |
945 | goto dead; | |
946 | } | |
947 | ||
948 | if (cpu_time_before(timer->it_clock, now, timer->it.cpu.expires)) { | |
949 | sample_to_timespec(timer->it_clock, | |
950 | cpu_time_sub(timer->it_clock, | |
951 | timer->it.cpu.expires, now), | |
952 | &itp->it_value); | |
953 | } else { | |
954 | /* | |
955 | * The timer should have expired already, but the firing | |
956 | * hasn't taken place yet. Say it's just about to expire. | |
957 | */ | |
958 | itp->it_value.tv_nsec = 1; | |
959 | itp->it_value.tv_sec = 0; | |
960 | } | |
961 | } | |
962 | ||
963 | /* | |
964 | * Check for any per-thread CPU timers that have fired and move them off | |
965 | * the tsk->cpu_timers[N] list onto the firing list. Here we update the | |
966 | * tsk->it_*_expires values to reflect the remaining thread CPU timers. | |
967 | */ | |
968 | static void check_thread_timers(struct task_struct *tsk, | |
969 | struct list_head *firing) | |
970 | { | |
e80eda94 | 971 | int maxfire; |
1da177e4 | 972 | struct list_head *timers = tsk->cpu_timers; |
78f2c7db | 973 | struct signal_struct *const sig = tsk->signal; |
d4bb5274 | 974 | unsigned long soft; |
1da177e4 | 975 | |
e80eda94 | 976 | maxfire = 20; |
f06febc9 | 977 | tsk->cputime_expires.prof_exp = cputime_zero; |
1da177e4 | 978 | while (!list_empty(timers)) { |
b5e61818 | 979 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
980 | struct cpu_timer_list, |
981 | entry); | |
e80eda94 | 982 | if (!--maxfire || cputime_lt(prof_ticks(tsk), t->expires.cpu)) { |
f06febc9 | 983 | tsk->cputime_expires.prof_exp = t->expires.cpu; |
1da177e4 LT |
984 | break; |
985 | } | |
986 | t->firing = 1; | |
987 | list_move_tail(&t->entry, firing); | |
988 | } | |
989 | ||
990 | ++timers; | |
e80eda94 | 991 | maxfire = 20; |
f06febc9 | 992 | tsk->cputime_expires.virt_exp = cputime_zero; |
1da177e4 | 993 | while (!list_empty(timers)) { |
b5e61818 | 994 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
995 | struct cpu_timer_list, |
996 | entry); | |
e80eda94 | 997 | if (!--maxfire || cputime_lt(virt_ticks(tsk), t->expires.cpu)) { |
f06febc9 | 998 | tsk->cputime_expires.virt_exp = t->expires.cpu; |
1da177e4 LT |
999 | break; |
1000 | } | |
1001 | t->firing = 1; | |
1002 | list_move_tail(&t->entry, firing); | |
1003 | } | |
1004 | ||
1005 | ++timers; | |
e80eda94 | 1006 | maxfire = 20; |
f06febc9 | 1007 | tsk->cputime_expires.sched_exp = 0; |
1da177e4 | 1008 | while (!list_empty(timers)) { |
b5e61818 | 1009 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
1010 | struct cpu_timer_list, |
1011 | entry); | |
41b86e9c | 1012 | if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) { |
f06febc9 | 1013 | tsk->cputime_expires.sched_exp = t->expires.sched; |
1da177e4 LT |
1014 | break; |
1015 | } | |
1016 | t->firing = 1; | |
1017 | list_move_tail(&t->entry, firing); | |
1018 | } | |
78f2c7db PZ |
1019 | |
1020 | /* | |
1021 | * Check for the special case thread timers. | |
1022 | */ | |
78d7d407 | 1023 | soft = ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_cur); |
d4bb5274 | 1024 | if (soft != RLIM_INFINITY) { |
78d7d407 JS |
1025 | unsigned long hard = |
1026 | ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_max); | |
78f2c7db | 1027 | |
5a52dd50 PZ |
1028 | if (hard != RLIM_INFINITY && |
1029 | tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { | |
78f2c7db PZ |
1030 | /* |
1031 | * At the hard limit, we just die. | |
1032 | * No need to calculate anything else now. | |
1033 | */ | |
1034 | __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); | |
1035 | return; | |
1036 | } | |
d4bb5274 | 1037 | if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) { |
78f2c7db PZ |
1038 | /* |
1039 | * At the soft limit, send a SIGXCPU every second. | |
1040 | */ | |
d4bb5274 JS |
1041 | if (soft < hard) { |
1042 | soft += USEC_PER_SEC; | |
1043 | sig->rlim[RLIMIT_RTTIME].rlim_cur = soft; | |
78f2c7db | 1044 | } |
81d50bb2 HS |
1045 | printk(KERN_INFO |
1046 | "RT Watchdog Timeout: %s[%d]\n", | |
1047 | tsk->comm, task_pid_nr(tsk)); | |
78f2c7db PZ |
1048 | __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); |
1049 | } | |
1050 | } | |
1da177e4 LT |
1051 | } |
1052 | ||
3fccfd67 PZ |
1053 | static void stop_process_timers(struct task_struct *tsk) |
1054 | { | |
1055 | struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; | |
1056 | unsigned long flags; | |
1057 | ||
1058 | if (!cputimer->running) | |
1059 | return; | |
1060 | ||
1061 | spin_lock_irqsave(&cputimer->lock, flags); | |
1062 | cputimer->running = 0; | |
1063 | spin_unlock_irqrestore(&cputimer->lock, flags); | |
1064 | } | |
1065 | ||
8356b5f9 SG |
1066 | static u32 onecputick; |
1067 | ||
42c4ab41 SG |
1068 | static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, |
1069 | cputime_t *expires, cputime_t cur_time, int signo) | |
1070 | { | |
1071 | if (cputime_eq(it->expires, cputime_zero)) | |
1072 | return; | |
1073 | ||
1074 | if (cputime_ge(cur_time, it->expires)) { | |
8356b5f9 SG |
1075 | if (!cputime_eq(it->incr, cputime_zero)) { |
1076 | it->expires = cputime_add(it->expires, it->incr); | |
1077 | it->error += it->incr_error; | |
1078 | if (it->error >= onecputick) { | |
1079 | it->expires = cputime_sub(it->expires, | |
a42548a1 | 1080 | cputime_one_jiffy); |
8356b5f9 SG |
1081 | it->error -= onecputick; |
1082 | } | |
3f0a525e | 1083 | } else { |
8356b5f9 | 1084 | it->expires = cputime_zero; |
3f0a525e | 1085 | } |
42c4ab41 | 1086 | |
3f0a525e XG |
1087 | trace_itimer_expire(signo == SIGPROF ? |
1088 | ITIMER_PROF : ITIMER_VIRTUAL, | |
1089 | tsk->signal->leader_pid, cur_time); | |
42c4ab41 SG |
1090 | __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); |
1091 | } | |
1092 | ||
1093 | if (!cputime_eq(it->expires, cputime_zero) && | |
1094 | (cputime_eq(*expires, cputime_zero) || | |
1095 | cputime_lt(it->expires, *expires))) { | |
1096 | *expires = it->expires; | |
1097 | } | |
1098 | } | |
1099 | ||
1da177e4 LT |
1100 | /* |
1101 | * Check for any per-thread CPU timers that have fired and move them | |
1102 | * off the tsk->*_timers list onto the firing list. Per-thread timers | |
1103 | * have already been taken off. | |
1104 | */ | |
1105 | static void check_process_timers(struct task_struct *tsk, | |
1106 | struct list_head *firing) | |
1107 | { | |
e80eda94 | 1108 | int maxfire; |
1da177e4 | 1109 | struct signal_struct *const sig = tsk->signal; |
f06febc9 | 1110 | cputime_t utime, ptime, virt_expires, prof_expires; |
41b86e9c | 1111 | unsigned long long sum_sched_runtime, sched_expires; |
1da177e4 | 1112 | struct list_head *timers = sig->cpu_timers; |
f06febc9 | 1113 | struct task_cputime cputime; |
d4bb5274 | 1114 | unsigned long soft; |
1da177e4 LT |
1115 | |
1116 | /* | |
1117 | * Don't sample the current process CPU clocks if there are no timers. | |
1118 | */ | |
1119 | if (list_empty(&timers[CPUCLOCK_PROF]) && | |
42c4ab41 | 1120 | cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) && |
1da177e4 LT |
1121 | sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY && |
1122 | list_empty(&timers[CPUCLOCK_VIRT]) && | |
42c4ab41 | 1123 | cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && |
4cd4c1b4 PZ |
1124 | list_empty(&timers[CPUCLOCK_SCHED])) { |
1125 | stop_process_timers(tsk); | |
1da177e4 | 1126 | return; |
4cd4c1b4 | 1127 | } |
1da177e4 LT |
1128 | |
1129 | /* | |
1130 | * Collect the current process totals. | |
1131 | */ | |
4cd4c1b4 | 1132 | thread_group_cputimer(tsk, &cputime); |
f06febc9 FM |
1133 | utime = cputime.utime; |
1134 | ptime = cputime_add(utime, cputime.stime); | |
1135 | sum_sched_runtime = cputime.sum_exec_runtime; | |
e80eda94 | 1136 | maxfire = 20; |
1da177e4 LT |
1137 | prof_expires = cputime_zero; |
1138 | while (!list_empty(timers)) { | |
ee7dd205 | 1139 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1140 | struct cpu_timer_list, |
1141 | entry); | |
ee7dd205 WC |
1142 | if (!--maxfire || cputime_lt(ptime, tl->expires.cpu)) { |
1143 | prof_expires = tl->expires.cpu; | |
1da177e4 LT |
1144 | break; |
1145 | } | |
ee7dd205 WC |
1146 | tl->firing = 1; |
1147 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1148 | } |
1149 | ||
1150 | ++timers; | |
e80eda94 | 1151 | maxfire = 20; |
1da177e4 LT |
1152 | virt_expires = cputime_zero; |
1153 | while (!list_empty(timers)) { | |
ee7dd205 | 1154 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1155 | struct cpu_timer_list, |
1156 | entry); | |
ee7dd205 WC |
1157 | if (!--maxfire || cputime_lt(utime, tl->expires.cpu)) { |
1158 | virt_expires = tl->expires.cpu; | |
1da177e4 LT |
1159 | break; |
1160 | } | |
ee7dd205 WC |
1161 | tl->firing = 1; |
1162 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1163 | } |
1164 | ||
1165 | ++timers; | |
e80eda94 | 1166 | maxfire = 20; |
1da177e4 LT |
1167 | sched_expires = 0; |
1168 | while (!list_empty(timers)) { | |
ee7dd205 | 1169 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1170 | struct cpu_timer_list, |
1171 | entry); | |
ee7dd205 WC |
1172 | if (!--maxfire || sum_sched_runtime < tl->expires.sched) { |
1173 | sched_expires = tl->expires.sched; | |
1da177e4 LT |
1174 | break; |
1175 | } | |
ee7dd205 WC |
1176 | tl->firing = 1; |
1177 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1178 | } |
1179 | ||
1180 | /* | |
1181 | * Check for the special case process timers. | |
1182 | */ | |
42c4ab41 SG |
1183 | check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime, |
1184 | SIGPROF); | |
1185 | check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime, | |
1186 | SIGVTALRM); | |
78d7d407 | 1187 | soft = ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur); |
d4bb5274 | 1188 | if (soft != RLIM_INFINITY) { |
1da177e4 | 1189 | unsigned long psecs = cputime_to_secs(ptime); |
78d7d407 JS |
1190 | unsigned long hard = |
1191 | ACCESS_ONCE(sig->rlim[RLIMIT_CPU].rlim_max); | |
1da177e4 | 1192 | cputime_t x; |
d4bb5274 | 1193 | if (psecs >= hard) { |
1da177e4 LT |
1194 | /* |
1195 | * At the hard limit, we just die. | |
1196 | * No need to calculate anything else now. | |
1197 | */ | |
1198 | __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); | |
1199 | return; | |
1200 | } | |
d4bb5274 | 1201 | if (psecs >= soft) { |
1da177e4 LT |
1202 | /* |
1203 | * At the soft limit, send a SIGXCPU every second. | |
1204 | */ | |
1205 | __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); | |
d4bb5274 JS |
1206 | if (soft < hard) { |
1207 | soft++; | |
1208 | sig->rlim[RLIMIT_CPU].rlim_cur = soft; | |
1da177e4 LT |
1209 | } |
1210 | } | |
d4bb5274 | 1211 | x = secs_to_cputime(soft); |
1da177e4 LT |
1212 | if (cputime_eq(prof_expires, cputime_zero) || |
1213 | cputime_lt(x, prof_expires)) { | |
1214 | prof_expires = x; | |
1215 | } | |
1216 | } | |
1217 | ||
f06febc9 FM |
1218 | if (!cputime_eq(prof_expires, cputime_zero) && |
1219 | (cputime_eq(sig->cputime_expires.prof_exp, cputime_zero) || | |
1220 | cputime_gt(sig->cputime_expires.prof_exp, prof_expires))) | |
1221 | sig->cputime_expires.prof_exp = prof_expires; | |
1222 | if (!cputime_eq(virt_expires, cputime_zero) && | |
1223 | (cputime_eq(sig->cputime_expires.virt_exp, cputime_zero) || | |
1224 | cputime_gt(sig->cputime_expires.virt_exp, virt_expires))) | |
1225 | sig->cputime_expires.virt_exp = virt_expires; | |
1226 | if (sched_expires != 0 && | |
1227 | (sig->cputime_expires.sched_exp == 0 || | |
1228 | sig->cputime_expires.sched_exp > sched_expires)) | |
1229 | sig->cputime_expires.sched_exp = sched_expires; | |
1da177e4 LT |
1230 | } |
1231 | ||
1232 | /* | |
1233 | * This is called from the signal code (via do_schedule_next_timer) | |
1234 | * when the last timer signal was delivered and we have to reload the timer. | |
1235 | */ | |
1236 | void posix_cpu_timer_schedule(struct k_itimer *timer) | |
1237 | { | |
1238 | struct task_struct *p = timer->it.cpu.task; | |
1239 | union cpu_time_count now; | |
1240 | ||
1241 | if (unlikely(p == NULL)) | |
1242 | /* | |
1243 | * The task was cleaned up already, no future firings. | |
1244 | */ | |
708f430d | 1245 | goto out; |
1da177e4 LT |
1246 | |
1247 | /* | |
1248 | * Fetch the current sample and update the timer's expiry time. | |
1249 | */ | |
1250 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
1251 | cpu_clock_sample(timer->it_clock, p, &now); | |
1252 | bump_cpu_timer(timer, now); | |
1253 | if (unlikely(p->exit_state)) { | |
1254 | clear_dead_task(timer, now); | |
708f430d | 1255 | goto out; |
1da177e4 LT |
1256 | } |
1257 | read_lock(&tasklist_lock); /* arm_timer needs it. */ | |
1258 | } else { | |
1259 | read_lock(&tasklist_lock); | |
1260 | if (unlikely(p->signal == NULL)) { | |
1261 | /* | |
1262 | * The process has been reaped. | |
1263 | * We can't even collect a sample any more. | |
1264 | */ | |
1265 | put_task_struct(p); | |
1266 | timer->it.cpu.task = p = NULL; | |
1267 | timer->it.cpu.expires.sched = 0; | |
708f430d | 1268 | goto out_unlock; |
1da177e4 LT |
1269 | } else if (unlikely(p->exit_state) && thread_group_empty(p)) { |
1270 | /* | |
1271 | * We've noticed that the thread is dead, but | |
1272 | * not yet reaped. Take this opportunity to | |
1273 | * drop our task ref. | |
1274 | */ | |
1275 | clear_dead_task(timer, now); | |
708f430d | 1276 | goto out_unlock; |
1da177e4 | 1277 | } |
3997ad31 | 1278 | cpu_timer_sample_group(timer->it_clock, p, &now); |
1da177e4 LT |
1279 | bump_cpu_timer(timer, now); |
1280 | /* Leave the tasklist_lock locked for the call below. */ | |
1281 | } | |
1282 | ||
1283 | /* | |
1284 | * Now re-arm for the new expiry time. | |
1285 | */ | |
1286 | arm_timer(timer, now); | |
1287 | ||
708f430d | 1288 | out_unlock: |
1da177e4 | 1289 | read_unlock(&tasklist_lock); |
708f430d RM |
1290 | |
1291 | out: | |
1292 | timer->it_overrun_last = timer->it_overrun; | |
1293 | timer->it_overrun = -1; | |
1294 | ++timer->it_requeue_pending; | |
1da177e4 LT |
1295 | } |
1296 | ||
f06febc9 FM |
1297 | /** |
1298 | * task_cputime_zero - Check a task_cputime struct for all zero fields. | |
1299 | * | |
1300 | * @cputime: The struct to compare. | |
1301 | * | |
1302 | * Checks @cputime to see if all fields are zero. Returns true if all fields | |
1303 | * are zero, false if any field is nonzero. | |
1304 | */ | |
1305 | static inline int task_cputime_zero(const struct task_cputime *cputime) | |
1306 | { | |
1307 | if (cputime_eq(cputime->utime, cputime_zero) && | |
1308 | cputime_eq(cputime->stime, cputime_zero) && | |
1309 | cputime->sum_exec_runtime == 0) | |
1310 | return 1; | |
1311 | return 0; | |
1312 | } | |
1313 | ||
1314 | /** | |
1315 | * task_cputime_expired - Compare two task_cputime entities. | |
1316 | * | |
1317 | * @sample: The task_cputime structure to be checked for expiration. | |
1318 | * @expires: Expiration times, against which @sample will be checked. | |
1319 | * | |
1320 | * Checks @sample against @expires to see if any field of @sample has expired. | |
1321 | * Returns true if any field of the former is greater than the corresponding | |
1322 | * field of the latter if the latter field is set. Otherwise returns false. | |
1323 | */ | |
1324 | static inline int task_cputime_expired(const struct task_cputime *sample, | |
1325 | const struct task_cputime *expires) | |
1326 | { | |
1327 | if (!cputime_eq(expires->utime, cputime_zero) && | |
1328 | cputime_ge(sample->utime, expires->utime)) | |
1329 | return 1; | |
1330 | if (!cputime_eq(expires->stime, cputime_zero) && | |
1331 | cputime_ge(cputime_add(sample->utime, sample->stime), | |
1332 | expires->stime)) | |
1333 | return 1; | |
1334 | if (expires->sum_exec_runtime != 0 && | |
1335 | sample->sum_exec_runtime >= expires->sum_exec_runtime) | |
1336 | return 1; | |
1337 | return 0; | |
1338 | } | |
1339 | ||
1340 | /** | |
1341 | * fastpath_timer_check - POSIX CPU timers fast path. | |
1342 | * | |
1343 | * @tsk: The task (thread) being checked. | |
f06febc9 | 1344 | * |
bb34d92f FM |
1345 | * Check the task and thread group timers. If both are zero (there are no |
1346 | * timers set) return false. Otherwise snapshot the task and thread group | |
1347 | * timers and compare them with the corresponding expiration times. Return | |
1348 | * true if a timer has expired, else return false. | |
f06febc9 | 1349 | */ |
bb34d92f | 1350 | static inline int fastpath_timer_check(struct task_struct *tsk) |
f06febc9 | 1351 | { |
ad133ba3 | 1352 | struct signal_struct *sig; |
bb34d92f | 1353 | |
ad133ba3 ON |
1354 | /* tsk == current, ensure it is safe to use ->signal/sighand */ |
1355 | if (unlikely(tsk->exit_state)) | |
f06febc9 | 1356 | return 0; |
bb34d92f FM |
1357 | |
1358 | if (!task_cputime_zero(&tsk->cputime_expires)) { | |
1359 | struct task_cputime task_sample = { | |
1360 | .utime = tsk->utime, | |
1361 | .stime = tsk->stime, | |
1362 | .sum_exec_runtime = tsk->se.sum_exec_runtime | |
1363 | }; | |
1364 | ||
1365 | if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) | |
1366 | return 1; | |
1367 | } | |
ad133ba3 ON |
1368 | |
1369 | sig = tsk->signal; | |
bb34d92f FM |
1370 | if (!task_cputime_zero(&sig->cputime_expires)) { |
1371 | struct task_cputime group_sample; | |
1372 | ||
4cd4c1b4 | 1373 | thread_group_cputimer(tsk, &group_sample); |
bb34d92f FM |
1374 | if (task_cputime_expired(&group_sample, &sig->cputime_expires)) |
1375 | return 1; | |
1376 | } | |
37bebc70 | 1377 | |
f55db609 | 1378 | return 0; |
f06febc9 FM |
1379 | } |
1380 | ||
1da177e4 LT |
1381 | /* |
1382 | * This is called from the timer interrupt handler. The irq handler has | |
1383 | * already updated our counts. We need to check if any timers fire now. | |
1384 | * Interrupts are disabled. | |
1385 | */ | |
1386 | void run_posix_cpu_timers(struct task_struct *tsk) | |
1387 | { | |
1388 | LIST_HEAD(firing); | |
1389 | struct k_itimer *timer, *next; | |
1390 | ||
1391 | BUG_ON(!irqs_disabled()); | |
1392 | ||
1da177e4 | 1393 | /* |
f06febc9 | 1394 | * The fast path checks that there are no expired thread or thread |
bb34d92f | 1395 | * group timers. If that's so, just return. |
1da177e4 | 1396 | */ |
bb34d92f | 1397 | if (!fastpath_timer_check(tsk)) |
f06febc9 | 1398 | return; |
5ce73a4a | 1399 | |
bb34d92f FM |
1400 | spin_lock(&tsk->sighand->siglock); |
1401 | /* | |
1402 | * Here we take off tsk->signal->cpu_timers[N] and | |
1403 | * tsk->cpu_timers[N] all the timers that are firing, and | |
1404 | * put them on the firing list. | |
1405 | */ | |
1406 | check_thread_timers(tsk, &firing); | |
1407 | check_process_timers(tsk, &firing); | |
1da177e4 | 1408 | |
bb34d92f FM |
1409 | /* |
1410 | * We must release these locks before taking any timer's lock. | |
1411 | * There is a potential race with timer deletion here, as the | |
1412 | * siglock now protects our private firing list. We have set | |
1413 | * the firing flag in each timer, so that a deletion attempt | |
1414 | * that gets the timer lock before we do will give it up and | |
1415 | * spin until we've taken care of that timer below. | |
1416 | */ | |
1417 | spin_unlock(&tsk->sighand->siglock); | |
1da177e4 LT |
1418 | |
1419 | /* | |
1420 | * Now that all the timers on our list have the firing flag, | |
1421 | * noone will touch their list entries but us. We'll take | |
1422 | * each timer's lock before clearing its firing flag, so no | |
1423 | * timer call will interfere. | |
1424 | */ | |
1425 | list_for_each_entry_safe(timer, next, &firing, it.cpu.entry) { | |
6e85c5ba HS |
1426 | int cpu_firing; |
1427 | ||
1da177e4 LT |
1428 | spin_lock(&timer->it_lock); |
1429 | list_del_init(&timer->it.cpu.entry); | |
6e85c5ba | 1430 | cpu_firing = timer->it.cpu.firing; |
1da177e4 LT |
1431 | timer->it.cpu.firing = 0; |
1432 | /* | |
1433 | * The firing flag is -1 if we collided with a reset | |
1434 | * of the timer, which already reported this | |
1435 | * almost-firing as an overrun. So don't generate an event. | |
1436 | */ | |
6e85c5ba | 1437 | if (likely(cpu_firing >= 0)) |
1da177e4 | 1438 | cpu_timer_fire(timer); |
1da177e4 LT |
1439 | spin_unlock(&timer->it_lock); |
1440 | } | |
1441 | } | |
1442 | ||
1443 | /* | |
f55db609 | 1444 | * Set one of the process-wide special case CPU timers or RLIMIT_CPU. |
f06febc9 | 1445 | * The tsk->sighand->siglock must be held by the caller. |
1da177e4 LT |
1446 | */ |
1447 | void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, | |
1448 | cputime_t *newval, cputime_t *oldval) | |
1449 | { | |
1450 | union cpu_time_count now; | |
1da177e4 LT |
1451 | |
1452 | BUG_ON(clock_idx == CPUCLOCK_SCHED); | |
4cd4c1b4 | 1453 | cpu_timer_sample_group(clock_idx, tsk, &now); |
1da177e4 LT |
1454 | |
1455 | if (oldval) { | |
f55db609 SG |
1456 | /* |
1457 | * We are setting itimer. The *oldval is absolute and we update | |
1458 | * it to be relative, *newval argument is relative and we update | |
1459 | * it to be absolute. | |
1460 | */ | |
1da177e4 LT |
1461 | if (!cputime_eq(*oldval, cputime_zero)) { |
1462 | if (cputime_le(*oldval, now.cpu)) { | |
1463 | /* Just about to fire. */ | |
a42548a1 | 1464 | *oldval = cputime_one_jiffy; |
1da177e4 LT |
1465 | } else { |
1466 | *oldval = cputime_sub(*oldval, now.cpu); | |
1467 | } | |
1468 | } | |
1469 | ||
1470 | if (cputime_eq(*newval, cputime_zero)) | |
1471 | return; | |
1472 | *newval = cputime_add(*newval, now.cpu); | |
1da177e4 LT |
1473 | } |
1474 | ||
1475 | /* | |
f55db609 SG |
1476 | * Update expiration cache if we are the earliest timer, or eventually |
1477 | * RLIMIT_CPU limit is earlier than prof_exp cpu timer expire. | |
1da177e4 | 1478 | */ |
f55db609 SG |
1479 | switch (clock_idx) { |
1480 | case CPUCLOCK_PROF: | |
1481 | if (expires_gt(tsk->signal->cputime_expires.prof_exp, *newval)) | |
f06febc9 | 1482 | tsk->signal->cputime_expires.prof_exp = *newval; |
f55db609 SG |
1483 | break; |
1484 | case CPUCLOCK_VIRT: | |
1485 | if (expires_gt(tsk->signal->cputime_expires.virt_exp, *newval)) | |
f06febc9 | 1486 | tsk->signal->cputime_expires.virt_exp = *newval; |
f55db609 | 1487 | break; |
1da177e4 LT |
1488 | } |
1489 | } | |
1490 | ||
e4b76555 TA |
1491 | static int do_cpu_nanosleep(const clockid_t which_clock, int flags, |
1492 | struct timespec *rqtp, struct itimerspec *it) | |
1da177e4 | 1493 | { |
1da177e4 LT |
1494 | struct k_itimer timer; |
1495 | int error; | |
1496 | ||
1da177e4 LT |
1497 | /* |
1498 | * Set up a temporary timer and then wait for it to go off. | |
1499 | */ | |
1500 | memset(&timer, 0, sizeof timer); | |
1501 | spin_lock_init(&timer.it_lock); | |
1502 | timer.it_clock = which_clock; | |
1503 | timer.it_overrun = -1; | |
1504 | error = posix_cpu_timer_create(&timer); | |
1505 | timer.it_process = current; | |
1506 | if (!error) { | |
1da177e4 | 1507 | static struct itimerspec zero_it; |
e4b76555 TA |
1508 | |
1509 | memset(it, 0, sizeof *it); | |
1510 | it->it_value = *rqtp; | |
1da177e4 LT |
1511 | |
1512 | spin_lock_irq(&timer.it_lock); | |
e4b76555 | 1513 | error = posix_cpu_timer_set(&timer, flags, it, NULL); |
1da177e4 LT |
1514 | if (error) { |
1515 | spin_unlock_irq(&timer.it_lock); | |
1516 | return error; | |
1517 | } | |
1518 | ||
1519 | while (!signal_pending(current)) { | |
1520 | if (timer.it.cpu.expires.sched == 0) { | |
1521 | /* | |
1522 | * Our timer fired and was reset. | |
1523 | */ | |
1524 | spin_unlock_irq(&timer.it_lock); | |
1525 | return 0; | |
1526 | } | |
1527 | ||
1528 | /* | |
1529 | * Block until cpu_timer_fire (or a signal) wakes us. | |
1530 | */ | |
1531 | __set_current_state(TASK_INTERRUPTIBLE); | |
1532 | spin_unlock_irq(&timer.it_lock); | |
1533 | schedule(); | |
1534 | spin_lock_irq(&timer.it_lock); | |
1535 | } | |
1536 | ||
1537 | /* | |
1538 | * We were interrupted by a signal. | |
1539 | */ | |
1540 | sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp); | |
e4b76555 | 1541 | posix_cpu_timer_set(&timer, 0, &zero_it, it); |
1da177e4 LT |
1542 | spin_unlock_irq(&timer.it_lock); |
1543 | ||
e4b76555 | 1544 | if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) { |
1da177e4 LT |
1545 | /* |
1546 | * It actually did fire already. | |
1547 | */ | |
1548 | return 0; | |
1549 | } | |
1550 | ||
e4b76555 TA |
1551 | error = -ERESTART_RESTARTBLOCK; |
1552 | } | |
1553 | ||
1554 | return error; | |
1555 | } | |
1556 | ||
1557 | int posix_cpu_nsleep(const clockid_t which_clock, int flags, | |
1558 | struct timespec *rqtp, struct timespec __user *rmtp) | |
1559 | { | |
1560 | struct restart_block *restart_block = | |
1561 | ¤t_thread_info()->restart_block; | |
1562 | struct itimerspec it; | |
1563 | int error; | |
1564 | ||
1565 | /* | |
1566 | * Diagnose required errors first. | |
1567 | */ | |
1568 | if (CPUCLOCK_PERTHREAD(which_clock) && | |
1569 | (CPUCLOCK_PID(which_clock) == 0 || | |
1570 | CPUCLOCK_PID(which_clock) == current->pid)) | |
1571 | return -EINVAL; | |
1572 | ||
1573 | error = do_cpu_nanosleep(which_clock, flags, rqtp, &it); | |
1574 | ||
1575 | if (error == -ERESTART_RESTARTBLOCK) { | |
1576 | ||
1577 | if (flags & TIMER_ABSTIME) | |
1578 | return -ERESTARTNOHAND; | |
1da177e4 | 1579 | /* |
e4b76555 TA |
1580 | * Report back to the user the time still remaining. |
1581 | */ | |
1582 | if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) | |
1da177e4 LT |
1583 | return -EFAULT; |
1584 | ||
1711ef38 | 1585 | restart_block->fn = posix_cpu_nsleep_restart; |
1da177e4 | 1586 | restart_block->arg0 = which_clock; |
97735f25 | 1587 | restart_block->arg1 = (unsigned long) rmtp; |
1da177e4 LT |
1588 | restart_block->arg2 = rqtp->tv_sec; |
1589 | restart_block->arg3 = rqtp->tv_nsec; | |
1da177e4 | 1590 | } |
1da177e4 LT |
1591 | return error; |
1592 | } | |
1593 | ||
1711ef38 | 1594 | long posix_cpu_nsleep_restart(struct restart_block *restart_block) |
1da177e4 LT |
1595 | { |
1596 | clockid_t which_clock = restart_block->arg0; | |
97735f25 TG |
1597 | struct timespec __user *rmtp; |
1598 | struct timespec t; | |
e4b76555 TA |
1599 | struct itimerspec it; |
1600 | int error; | |
97735f25 TG |
1601 | |
1602 | rmtp = (struct timespec __user *) restart_block->arg1; | |
1603 | t.tv_sec = restart_block->arg2; | |
1604 | t.tv_nsec = restart_block->arg3; | |
1605 | ||
1da177e4 | 1606 | restart_block->fn = do_no_restart_syscall; |
e4b76555 TA |
1607 | error = do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t, &it); |
1608 | ||
1609 | if (error == -ERESTART_RESTARTBLOCK) { | |
1610 | /* | |
1611 | * Report back to the user the time still remaining. | |
1612 | */ | |
1613 | if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) | |
1614 | return -EFAULT; | |
1615 | ||
1616 | restart_block->fn = posix_cpu_nsleep_restart; | |
1617 | restart_block->arg0 = which_clock; | |
1618 | restart_block->arg1 = (unsigned long) rmtp; | |
1619 | restart_block->arg2 = t.tv_sec; | |
1620 | restart_block->arg3 = t.tv_nsec; | |
1621 | } | |
1622 | return error; | |
1623 | ||
1da177e4 LT |
1624 | } |
1625 | ||
1626 | ||
1627 | #define PROCESS_CLOCK MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED) | |
1628 | #define THREAD_CLOCK MAKE_THREAD_CPUCLOCK(0, CPUCLOCK_SCHED) | |
1629 | ||
a924b04d TG |
1630 | static int process_cpu_clock_getres(const clockid_t which_clock, |
1631 | struct timespec *tp) | |
1da177e4 LT |
1632 | { |
1633 | return posix_cpu_clock_getres(PROCESS_CLOCK, tp); | |
1634 | } | |
a924b04d TG |
1635 | static int process_cpu_clock_get(const clockid_t which_clock, |
1636 | struct timespec *tp) | |
1da177e4 LT |
1637 | { |
1638 | return posix_cpu_clock_get(PROCESS_CLOCK, tp); | |
1639 | } | |
1640 | static int process_cpu_timer_create(struct k_itimer *timer) | |
1641 | { | |
1642 | timer->it_clock = PROCESS_CLOCK; | |
1643 | return posix_cpu_timer_create(timer); | |
1644 | } | |
a924b04d | 1645 | static int process_cpu_nsleep(const clockid_t which_clock, int flags, |
97735f25 TG |
1646 | struct timespec *rqtp, |
1647 | struct timespec __user *rmtp) | |
1da177e4 | 1648 | { |
97735f25 | 1649 | return posix_cpu_nsleep(PROCESS_CLOCK, flags, rqtp, rmtp); |
1da177e4 | 1650 | } |
1711ef38 TA |
1651 | static long process_cpu_nsleep_restart(struct restart_block *restart_block) |
1652 | { | |
1653 | return -EINVAL; | |
1654 | } | |
a924b04d TG |
1655 | static int thread_cpu_clock_getres(const clockid_t which_clock, |
1656 | struct timespec *tp) | |
1da177e4 LT |
1657 | { |
1658 | return posix_cpu_clock_getres(THREAD_CLOCK, tp); | |
1659 | } | |
a924b04d TG |
1660 | static int thread_cpu_clock_get(const clockid_t which_clock, |
1661 | struct timespec *tp) | |
1da177e4 LT |
1662 | { |
1663 | return posix_cpu_clock_get(THREAD_CLOCK, tp); | |
1664 | } | |
1665 | static int thread_cpu_timer_create(struct k_itimer *timer) | |
1666 | { | |
1667 | timer->it_clock = THREAD_CLOCK; | |
1668 | return posix_cpu_timer_create(timer); | |
1669 | } | |
a924b04d | 1670 | static int thread_cpu_nsleep(const clockid_t which_clock, int flags, |
97735f25 | 1671 | struct timespec *rqtp, struct timespec __user *rmtp) |
1da177e4 LT |
1672 | { |
1673 | return -EINVAL; | |
1674 | } | |
1711ef38 TA |
1675 | static long thread_cpu_nsleep_restart(struct restart_block *restart_block) |
1676 | { | |
1677 | return -EINVAL; | |
1678 | } | |
1da177e4 LT |
1679 | |
1680 | static __init int init_posix_cpu_timers(void) | |
1681 | { | |
1682 | struct k_clock process = { | |
1683 | .clock_getres = process_cpu_clock_getres, | |
1684 | .clock_get = process_cpu_clock_get, | |
1685 | .clock_set = do_posix_clock_nosettime, | |
1686 | .timer_create = process_cpu_timer_create, | |
1687 | .nsleep = process_cpu_nsleep, | |
1711ef38 | 1688 | .nsleep_restart = process_cpu_nsleep_restart, |
1da177e4 LT |
1689 | }; |
1690 | struct k_clock thread = { | |
1691 | .clock_getres = thread_cpu_clock_getres, | |
1692 | .clock_get = thread_cpu_clock_get, | |
1693 | .clock_set = do_posix_clock_nosettime, | |
1694 | .timer_create = thread_cpu_timer_create, | |
1695 | .nsleep = thread_cpu_nsleep, | |
1711ef38 | 1696 | .nsleep_restart = thread_cpu_nsleep_restart, |
1da177e4 | 1697 | }; |
8356b5f9 | 1698 | struct timespec ts; |
1da177e4 LT |
1699 | |
1700 | register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); | |
1701 | register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); | |
1702 | ||
a42548a1 | 1703 | cputime_to_timespec(cputime_one_jiffy, &ts); |
8356b5f9 SG |
1704 | onecputick = ts.tv_nsec; |
1705 | WARN_ON(ts.tv_sec != 0); | |
1706 | ||
1da177e4 LT |
1707 | return 0; |
1708 | } | |
1709 | __initcall(init_posix_cpu_timers); |