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Commit | Line | Data |
---|---|---|
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 FM |
13 | /* |
14 | * Called after updating RLIMIT_CPU to set timer expiration if necessary. | |
15 | */ | |
16 | void update_rlimit_cpu(unsigned long rlim_new) | |
17 | { | |
42c4ab41 SG |
18 | cputime_t cputime = secs_to_cputime(rlim_new); |
19 | struct signal_struct *const sig = current->signal; | |
f06febc9 | 20 | |
42c4ab41 SG |
21 | if (cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) || |
22 | cputime_gt(sig->it[CPUCLOCK_PROF].expires, cputime)) { | |
f06febc9 FM |
23 | spin_lock_irq(¤t->sighand->siglock); |
24 | set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL); | |
25 | spin_unlock_irq(¤t->sighand->siglock); | |
26 | } | |
27 | } | |
28 | ||
a924b04d | 29 | static int check_clock(const clockid_t which_clock) |
1da177e4 LT |
30 | { |
31 | int error = 0; | |
32 | struct task_struct *p; | |
33 | const pid_t pid = CPUCLOCK_PID(which_clock); | |
34 | ||
35 | if (CPUCLOCK_WHICH(which_clock) >= CPUCLOCK_MAX) | |
36 | return -EINVAL; | |
37 | ||
38 | if (pid == 0) | |
39 | return 0; | |
40 | ||
41 | read_lock(&tasklist_lock); | |
8dc86af0 | 42 | p = find_task_by_vpid(pid); |
bac0abd6 PE |
43 | if (!p || !(CPUCLOCK_PERTHREAD(which_clock) ? |
44 | same_thread_group(p, current) : thread_group_leader(p))) { | |
1da177e4 LT |
45 | error = -EINVAL; |
46 | } | |
47 | read_unlock(&tasklist_lock); | |
48 | ||
49 | return error; | |
50 | } | |
51 | ||
52 | static inline union cpu_time_count | |
a924b04d | 53 | timespec_to_sample(const clockid_t which_clock, const struct timespec *tp) |
1da177e4 LT |
54 | { |
55 | union cpu_time_count ret; | |
56 | ret.sched = 0; /* high half always zero when .cpu used */ | |
57 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
ee500f27 | 58 | ret.sched = (unsigned long long)tp->tv_sec * NSEC_PER_SEC + tp->tv_nsec; |
1da177e4 LT |
59 | } else { |
60 | ret.cpu = timespec_to_cputime(tp); | |
61 | } | |
62 | return ret; | |
63 | } | |
64 | ||
a924b04d | 65 | static void sample_to_timespec(const clockid_t which_clock, |
1da177e4 LT |
66 | union cpu_time_count cpu, |
67 | struct timespec *tp) | |
68 | { | |
f8bd2258 RZ |
69 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) |
70 | *tp = ns_to_timespec(cpu.sched); | |
71 | else | |
1da177e4 | 72 | cputime_to_timespec(cpu.cpu, tp); |
1da177e4 LT |
73 | } |
74 | ||
a924b04d | 75 | static inline int cpu_time_before(const clockid_t which_clock, |
1da177e4 LT |
76 | union cpu_time_count now, |
77 | union cpu_time_count then) | |
78 | { | |
79 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
80 | return now.sched < then.sched; | |
81 | } else { | |
82 | return cputime_lt(now.cpu, then.cpu); | |
83 | } | |
84 | } | |
a924b04d | 85 | static inline void cpu_time_add(const clockid_t which_clock, |
1da177e4 LT |
86 | union cpu_time_count *acc, |
87 | union cpu_time_count val) | |
88 | { | |
89 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
90 | acc->sched += val.sched; | |
91 | } else { | |
92 | acc->cpu = cputime_add(acc->cpu, val.cpu); | |
93 | } | |
94 | } | |
a924b04d | 95 | static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock, |
1da177e4 LT |
96 | union cpu_time_count a, |
97 | union cpu_time_count b) | |
98 | { | |
99 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
100 | a.sched -= b.sched; | |
101 | } else { | |
102 | a.cpu = cputime_sub(a.cpu, b.cpu); | |
103 | } | |
104 | return a; | |
105 | } | |
106 | ||
ac08c264 TG |
107 | /* |
108 | * Divide and limit the result to res >= 1 | |
109 | * | |
110 | * This is necessary to prevent signal delivery starvation, when the result of | |
111 | * the division would be rounded down to 0. | |
112 | */ | |
113 | static inline cputime_t cputime_div_non_zero(cputime_t time, unsigned long div) | |
114 | { | |
115 | cputime_t res = cputime_div(time, div); | |
116 | ||
117 | return max_t(cputime_t, res, 1); | |
118 | } | |
119 | ||
1da177e4 LT |
120 | /* |
121 | * Update expiry time from increment, and increase overrun count, | |
122 | * given the current clock sample. | |
123 | */ | |
7a4ed937 | 124 | static void bump_cpu_timer(struct k_itimer *timer, |
1da177e4 LT |
125 | union cpu_time_count now) |
126 | { | |
127 | int i; | |
128 | ||
129 | if (timer->it.cpu.incr.sched == 0) | |
130 | return; | |
131 | ||
132 | if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) { | |
133 | unsigned long long delta, incr; | |
134 | ||
135 | if (now.sched < timer->it.cpu.expires.sched) | |
136 | return; | |
137 | incr = timer->it.cpu.incr.sched; | |
138 | delta = now.sched + incr - timer->it.cpu.expires.sched; | |
139 | /* Don't use (incr*2 < delta), incr*2 might overflow. */ | |
140 | for (i = 0; incr < delta - incr; i++) | |
141 | incr = incr << 1; | |
142 | for (; i >= 0; incr >>= 1, i--) { | |
7a4ed937 | 143 | if (delta < incr) |
1da177e4 LT |
144 | continue; |
145 | timer->it.cpu.expires.sched += incr; | |
146 | timer->it_overrun += 1 << i; | |
147 | delta -= incr; | |
148 | } | |
149 | } else { | |
150 | cputime_t delta, incr; | |
151 | ||
152 | if (cputime_lt(now.cpu, timer->it.cpu.expires.cpu)) | |
153 | return; | |
154 | incr = timer->it.cpu.incr.cpu; | |
155 | delta = cputime_sub(cputime_add(now.cpu, incr), | |
156 | timer->it.cpu.expires.cpu); | |
157 | /* Don't use (incr*2 < delta), incr*2 might overflow. */ | |
158 | for (i = 0; cputime_lt(incr, cputime_sub(delta, incr)); i++) | |
159 | incr = cputime_add(incr, incr); | |
160 | for (; i >= 0; incr = cputime_halve(incr), i--) { | |
7a4ed937 | 161 | if (cputime_lt(delta, incr)) |
1da177e4 LT |
162 | continue; |
163 | timer->it.cpu.expires.cpu = | |
164 | cputime_add(timer->it.cpu.expires.cpu, incr); | |
165 | timer->it_overrun += 1 << i; | |
166 | delta = cputime_sub(delta, incr); | |
167 | } | |
168 | } | |
169 | } | |
170 | ||
171 | static inline cputime_t prof_ticks(struct task_struct *p) | |
172 | { | |
173 | return cputime_add(p->utime, p->stime); | |
174 | } | |
175 | static inline cputime_t virt_ticks(struct task_struct *p) | |
176 | { | |
177 | return p->utime; | |
178 | } | |
1da177e4 | 179 | |
a924b04d | 180 | int posix_cpu_clock_getres(const clockid_t which_clock, struct timespec *tp) |
1da177e4 LT |
181 | { |
182 | int error = check_clock(which_clock); | |
183 | if (!error) { | |
184 | tp->tv_sec = 0; | |
185 | tp->tv_nsec = ((NSEC_PER_SEC + HZ - 1) / HZ); | |
186 | if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) { | |
187 | /* | |
188 | * If sched_clock is using a cycle counter, we | |
189 | * don't have any idea of its true resolution | |
190 | * exported, but it is much more than 1s/HZ. | |
191 | */ | |
192 | tp->tv_nsec = 1; | |
193 | } | |
194 | } | |
195 | return error; | |
196 | } | |
197 | ||
a924b04d | 198 | int posix_cpu_clock_set(const clockid_t which_clock, const struct timespec *tp) |
1da177e4 LT |
199 | { |
200 | /* | |
201 | * You can never reset a CPU clock, but we check for other errors | |
202 | * in the call before failing with EPERM. | |
203 | */ | |
204 | int error = check_clock(which_clock); | |
205 | if (error == 0) { | |
206 | error = -EPERM; | |
207 | } | |
208 | return error; | |
209 | } | |
210 | ||
211 | ||
212 | /* | |
213 | * Sample a per-thread clock for the given task. | |
214 | */ | |
a924b04d | 215 | static int cpu_clock_sample(const clockid_t which_clock, struct task_struct *p, |
1da177e4 LT |
216 | union cpu_time_count *cpu) |
217 | { | |
218 | switch (CPUCLOCK_WHICH(which_clock)) { | |
219 | default: | |
220 | return -EINVAL; | |
221 | case CPUCLOCK_PROF: | |
222 | cpu->cpu = prof_ticks(p); | |
223 | break; | |
224 | case CPUCLOCK_VIRT: | |
225 | cpu->cpu = virt_ticks(p); | |
226 | break; | |
227 | case CPUCLOCK_SCHED: | |
c5f8d995 | 228 | cpu->sched = task_sched_runtime(p); |
1da177e4 LT |
229 | break; |
230 | } | |
231 | return 0; | |
232 | } | |
233 | ||
4cd4c1b4 PZ |
234 | void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times) |
235 | { | |
236 | struct sighand_struct *sighand; | |
237 | struct signal_struct *sig; | |
238 | struct task_struct *t; | |
239 | ||
240 | *times = INIT_CPUTIME; | |
241 | ||
242 | rcu_read_lock(); | |
243 | sighand = rcu_dereference(tsk->sighand); | |
244 | if (!sighand) | |
245 | goto out; | |
246 | ||
247 | sig = tsk->signal; | |
248 | ||
249 | t = tsk; | |
250 | do { | |
251 | times->utime = cputime_add(times->utime, t->utime); | |
252 | times->stime = cputime_add(times->stime, t->stime); | |
253 | times->sum_exec_runtime += t->se.sum_exec_runtime; | |
254 | ||
255 | t = next_thread(t); | |
256 | } while (t != tsk); | |
257 | ||
258 | times->utime = cputime_add(times->utime, sig->utime); | |
259 | times->stime = cputime_add(times->stime, sig->stime); | |
260 | times->sum_exec_runtime += sig->sum_sched_runtime; | |
261 | out: | |
262 | rcu_read_unlock(); | |
263 | } | |
264 | ||
4da94d49 PZ |
265 | static void update_gt_cputime(struct task_cputime *a, struct task_cputime *b) |
266 | { | |
267 | if (cputime_gt(b->utime, a->utime)) | |
268 | a->utime = b->utime; | |
269 | ||
270 | if (cputime_gt(b->stime, a->stime)) | |
271 | a->stime = b->stime; | |
272 | ||
273 | if (b->sum_exec_runtime > a->sum_exec_runtime) | |
274 | a->sum_exec_runtime = b->sum_exec_runtime; | |
275 | } | |
276 | ||
277 | void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times) | |
278 | { | |
279 | struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; | |
280 | struct task_cputime sum; | |
281 | unsigned long flags; | |
282 | ||
283 | spin_lock_irqsave(&cputimer->lock, flags); | |
284 | if (!cputimer->running) { | |
285 | cputimer->running = 1; | |
286 | /* | |
287 | * The POSIX timer interface allows for absolute time expiry | |
288 | * values through the TIMER_ABSTIME flag, therefore we have | |
289 | * to synchronize the timer to the clock every time we start | |
290 | * it. | |
291 | */ | |
292 | thread_group_cputime(tsk, &sum); | |
293 | update_gt_cputime(&cputimer->cputime, &sum); | |
294 | } | |
295 | *times = cputimer->cputime; | |
296 | spin_unlock_irqrestore(&cputimer->lock, flags); | |
297 | } | |
298 | ||
1da177e4 LT |
299 | /* |
300 | * Sample a process (thread group) clock for the given group_leader task. | |
301 | * Must be called with tasklist_lock held for reading. | |
1da177e4 | 302 | */ |
bb34d92f FM |
303 | static int cpu_clock_sample_group(const clockid_t which_clock, |
304 | struct task_struct *p, | |
305 | union cpu_time_count *cpu) | |
1da177e4 | 306 | { |
f06febc9 FM |
307 | struct task_cputime cputime; |
308 | ||
eccdaeaf | 309 | switch (CPUCLOCK_WHICH(which_clock)) { |
1da177e4 LT |
310 | default: |
311 | return -EINVAL; | |
312 | case CPUCLOCK_PROF: | |
c5f8d995 | 313 | thread_group_cputime(p, &cputime); |
f06febc9 | 314 | cpu->cpu = cputime_add(cputime.utime, cputime.stime); |
1da177e4 LT |
315 | break; |
316 | case CPUCLOCK_VIRT: | |
c5f8d995 | 317 | thread_group_cputime(p, &cputime); |
f06febc9 | 318 | cpu->cpu = cputime.utime; |
1da177e4 LT |
319 | break; |
320 | case CPUCLOCK_SCHED: | |
c5f8d995 | 321 | cpu->sched = thread_group_sched_runtime(p); |
1da177e4 LT |
322 | break; |
323 | } | |
324 | return 0; | |
325 | } | |
326 | ||
1da177e4 | 327 | |
a924b04d | 328 | int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) |
1da177e4 LT |
329 | { |
330 | const pid_t pid = CPUCLOCK_PID(which_clock); | |
331 | int error = -EINVAL; | |
332 | union cpu_time_count rtn; | |
333 | ||
334 | if (pid == 0) { | |
335 | /* | |
336 | * Special case constant value for our own clocks. | |
337 | * We don't have to do any lookup to find ourselves. | |
338 | */ | |
339 | if (CPUCLOCK_PERTHREAD(which_clock)) { | |
340 | /* | |
341 | * Sampling just ourselves we can do with no locking. | |
342 | */ | |
343 | error = cpu_clock_sample(which_clock, | |
344 | current, &rtn); | |
345 | } else { | |
346 | read_lock(&tasklist_lock); | |
347 | error = cpu_clock_sample_group(which_clock, | |
348 | current, &rtn); | |
349 | read_unlock(&tasklist_lock); | |
350 | } | |
351 | } else { | |
352 | /* | |
353 | * Find the given PID, and validate that the caller | |
354 | * should be able to see it. | |
355 | */ | |
356 | struct task_struct *p; | |
1f2ea083 | 357 | rcu_read_lock(); |
8dc86af0 | 358 | p = find_task_by_vpid(pid); |
1da177e4 LT |
359 | if (p) { |
360 | if (CPUCLOCK_PERTHREAD(which_clock)) { | |
bac0abd6 | 361 | if (same_thread_group(p, current)) { |
1da177e4 LT |
362 | error = cpu_clock_sample(which_clock, |
363 | p, &rtn); | |
364 | } | |
1f2ea083 PM |
365 | } else { |
366 | read_lock(&tasklist_lock); | |
bac0abd6 | 367 | if (thread_group_leader(p) && p->signal) { |
1f2ea083 PM |
368 | error = |
369 | cpu_clock_sample_group(which_clock, | |
370 | p, &rtn); | |
371 | } | |
372 | read_unlock(&tasklist_lock); | |
1da177e4 LT |
373 | } |
374 | } | |
1f2ea083 | 375 | rcu_read_unlock(); |
1da177e4 LT |
376 | } |
377 | ||
378 | if (error) | |
379 | return error; | |
380 | sample_to_timespec(which_clock, rtn, tp); | |
381 | return 0; | |
382 | } | |
383 | ||
384 | ||
385 | /* | |
386 | * Validate the clockid_t for a new CPU-clock timer, and initialize the timer. | |
ba5ea951 SG |
387 | * This is called from sys_timer_create() and do_cpu_nanosleep() with the |
388 | * new timer already all-zeros initialized. | |
1da177e4 LT |
389 | */ |
390 | int posix_cpu_timer_create(struct k_itimer *new_timer) | |
391 | { | |
392 | int ret = 0; | |
393 | const pid_t pid = CPUCLOCK_PID(new_timer->it_clock); | |
394 | struct task_struct *p; | |
395 | ||
396 | if (CPUCLOCK_WHICH(new_timer->it_clock) >= CPUCLOCK_MAX) | |
397 | return -EINVAL; | |
398 | ||
399 | INIT_LIST_HEAD(&new_timer->it.cpu.entry); | |
1da177e4 LT |
400 | |
401 | read_lock(&tasklist_lock); | |
402 | if (CPUCLOCK_PERTHREAD(new_timer->it_clock)) { | |
403 | if (pid == 0) { | |
404 | p = current; | |
405 | } else { | |
8dc86af0 | 406 | p = find_task_by_vpid(pid); |
bac0abd6 | 407 | if (p && !same_thread_group(p, current)) |
1da177e4 LT |
408 | p = NULL; |
409 | } | |
410 | } else { | |
411 | if (pid == 0) { | |
412 | p = current->group_leader; | |
413 | } else { | |
8dc86af0 | 414 | p = find_task_by_vpid(pid); |
bac0abd6 | 415 | if (p && !thread_group_leader(p)) |
1da177e4 LT |
416 | p = NULL; |
417 | } | |
418 | } | |
419 | new_timer->it.cpu.task = p; | |
420 | if (p) { | |
421 | get_task_struct(p); | |
422 | } else { | |
423 | ret = -EINVAL; | |
424 | } | |
425 | read_unlock(&tasklist_lock); | |
426 | ||
427 | return ret; | |
428 | } | |
429 | ||
430 | /* | |
431 | * Clean up a CPU-clock timer that is about to be destroyed. | |
432 | * This is called from timer deletion with the timer already locked. | |
433 | * If we return TIMER_RETRY, it's necessary to release the timer's lock | |
434 | * and try again. (This happens when the timer is in the middle of firing.) | |
435 | */ | |
436 | int posix_cpu_timer_del(struct k_itimer *timer) | |
437 | { | |
438 | struct task_struct *p = timer->it.cpu.task; | |
108150ea | 439 | int ret = 0; |
1da177e4 | 440 | |
108150ea | 441 | if (likely(p != NULL)) { |
9465bee8 LT |
442 | read_lock(&tasklist_lock); |
443 | if (unlikely(p->signal == NULL)) { | |
444 | /* | |
445 | * We raced with the reaping of the task. | |
446 | * The deletion should have cleared us off the list. | |
447 | */ | |
448 | BUG_ON(!list_empty(&timer->it.cpu.entry)); | |
449 | } else { | |
9465bee8 | 450 | spin_lock(&p->sighand->siglock); |
108150ea ON |
451 | if (timer->it.cpu.firing) |
452 | ret = TIMER_RETRY; | |
453 | else | |
454 | list_del(&timer->it.cpu.entry); | |
9465bee8 LT |
455 | spin_unlock(&p->sighand->siglock); |
456 | } | |
457 | read_unlock(&tasklist_lock); | |
108150ea ON |
458 | |
459 | if (!ret) | |
460 | put_task_struct(p); | |
1da177e4 | 461 | } |
1da177e4 | 462 | |
108150ea | 463 | return ret; |
1da177e4 LT |
464 | } |
465 | ||
466 | /* | |
467 | * Clean out CPU timers still ticking when a thread exited. The task | |
468 | * pointer is cleared, and the expiry time is replaced with the residual | |
469 | * time for later timer_gettime calls to return. | |
470 | * This must be called with the siglock held. | |
471 | */ | |
472 | static void cleanup_timers(struct list_head *head, | |
473 | cputime_t utime, cputime_t stime, | |
41b86e9c | 474 | unsigned long long sum_exec_runtime) |
1da177e4 LT |
475 | { |
476 | struct cpu_timer_list *timer, *next; | |
477 | cputime_t ptime = cputime_add(utime, stime); | |
478 | ||
479 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 LT |
480 | list_del_init(&timer->entry); |
481 | if (cputime_lt(timer->expires.cpu, ptime)) { | |
482 | timer->expires.cpu = cputime_zero; | |
483 | } else { | |
484 | timer->expires.cpu = cputime_sub(timer->expires.cpu, | |
485 | ptime); | |
486 | } | |
487 | } | |
488 | ||
489 | ++head; | |
490 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 LT |
491 | list_del_init(&timer->entry); |
492 | if (cputime_lt(timer->expires.cpu, utime)) { | |
493 | timer->expires.cpu = cputime_zero; | |
494 | } else { | |
495 | timer->expires.cpu = cputime_sub(timer->expires.cpu, | |
496 | utime); | |
497 | } | |
498 | } | |
499 | ||
500 | ++head; | |
501 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 | 502 | list_del_init(&timer->entry); |
41b86e9c | 503 | if (timer->expires.sched < sum_exec_runtime) { |
1da177e4 LT |
504 | timer->expires.sched = 0; |
505 | } else { | |
41b86e9c | 506 | timer->expires.sched -= sum_exec_runtime; |
1da177e4 LT |
507 | } |
508 | } | |
509 | } | |
510 | ||
511 | /* | |
512 | * These are both called with the siglock held, when the current thread | |
513 | * is being reaped. When the final (leader) thread in the group is reaped, | |
514 | * posix_cpu_timers_exit_group will be called after posix_cpu_timers_exit. | |
515 | */ | |
516 | void posix_cpu_timers_exit(struct task_struct *tsk) | |
517 | { | |
518 | cleanup_timers(tsk->cpu_timers, | |
41b86e9c | 519 | tsk->utime, tsk->stime, tsk->se.sum_exec_runtime); |
1da177e4 LT |
520 | |
521 | } | |
522 | void posix_cpu_timers_exit_group(struct task_struct *tsk) | |
523 | { | |
17d42c1c | 524 | struct signal_struct *const sig = tsk->signal; |
ca531a0a | 525 | |
f06febc9 | 526 | cleanup_timers(tsk->signal->cpu_timers, |
17d42c1c SG |
527 | cputime_add(tsk->utime, sig->utime), |
528 | cputime_add(tsk->stime, sig->stime), | |
529 | tsk->se.sum_exec_runtime + sig->sum_sched_runtime); | |
1da177e4 LT |
530 | } |
531 | ||
532 | static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) | |
533 | { | |
534 | /* | |
535 | * That's all for this thread or process. | |
536 | * We leave our residual in expires to be reported. | |
537 | */ | |
538 | put_task_struct(timer->it.cpu.task); | |
539 | timer->it.cpu.task = NULL; | |
540 | timer->it.cpu.expires = cpu_time_sub(timer->it_clock, | |
541 | timer->it.cpu.expires, | |
542 | now); | |
543 | } | |
544 | ||
d1e3b6d1 SG |
545 | static inline int expires_gt(cputime_t expires, cputime_t new_exp) |
546 | { | |
547 | return cputime_eq(expires, cputime_zero) || | |
548 | cputime_gt(expires, new_exp); | |
549 | } | |
550 | ||
551 | static inline int expires_le(cputime_t expires, cputime_t new_exp) | |
552 | { | |
553 | return !cputime_eq(expires, cputime_zero) && | |
554 | cputime_le(expires, new_exp); | |
555 | } | |
1da177e4 LT |
556 | /* |
557 | * Insert the timer on the appropriate list before any timers that | |
558 | * expire later. This must be called with the tasklist_lock held | |
559 | * for reading, and interrupts disabled. | |
560 | */ | |
561 | static void arm_timer(struct k_itimer *timer, union cpu_time_count now) | |
562 | { | |
563 | struct task_struct *p = timer->it.cpu.task; | |
564 | struct list_head *head, *listpos; | |
565 | struct cpu_timer_list *const nt = &timer->it.cpu; | |
566 | struct cpu_timer_list *next; | |
567 | unsigned long i; | |
568 | ||
569 | head = (CPUCLOCK_PERTHREAD(timer->it_clock) ? | |
570 | p->cpu_timers : p->signal->cpu_timers); | |
571 | head += CPUCLOCK_WHICH(timer->it_clock); | |
572 | ||
573 | BUG_ON(!irqs_disabled()); | |
574 | spin_lock(&p->sighand->siglock); | |
575 | ||
576 | listpos = head; | |
577 | if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) { | |
578 | list_for_each_entry(next, head, entry) { | |
70ab81c2 | 579 | if (next->expires.sched > nt->expires.sched) |
1da177e4 | 580 | break; |
70ab81c2 | 581 | listpos = &next->entry; |
1da177e4 LT |
582 | } |
583 | } else { | |
584 | list_for_each_entry(next, head, entry) { | |
70ab81c2 | 585 | if (cputime_gt(next->expires.cpu, nt->expires.cpu)) |
1da177e4 | 586 | break; |
70ab81c2 | 587 | listpos = &next->entry; |
1da177e4 LT |
588 | } |
589 | } | |
590 | list_add(&nt->entry, listpos); | |
591 | ||
592 | if (listpos == head) { | |
593 | /* | |
594 | * We are the new earliest-expiring timer. | |
595 | * If we are a thread timer, there can always | |
596 | * be a process timer telling us to stop earlier. | |
597 | */ | |
598 | ||
599 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
d1e3b6d1 SG |
600 | union cpu_time_count *exp = &nt->expires; |
601 | ||
1da177e4 LT |
602 | switch (CPUCLOCK_WHICH(timer->it_clock)) { |
603 | default: | |
604 | BUG(); | |
605 | case CPUCLOCK_PROF: | |
d1e3b6d1 SG |
606 | if (expires_gt(p->cputime_expires.prof_exp, |
607 | exp->cpu)) | |
608 | p->cputime_expires.prof_exp = exp->cpu; | |
1da177e4 LT |
609 | break; |
610 | case CPUCLOCK_VIRT: | |
d1e3b6d1 SG |
611 | if (expires_gt(p->cputime_expires.virt_exp, |
612 | exp->cpu)) | |
613 | p->cputime_expires.virt_exp = exp->cpu; | |
1da177e4 LT |
614 | break; |
615 | case CPUCLOCK_SCHED: | |
f06febc9 | 616 | if (p->cputime_expires.sched_exp == 0 || |
d1e3b6d1 | 617 | p->cputime_expires.sched_exp > exp->sched) |
f06febc9 | 618 | p->cputime_expires.sched_exp = |
d1e3b6d1 | 619 | exp->sched; |
1da177e4 LT |
620 | break; |
621 | } | |
622 | } else { | |
42c4ab41 SG |
623 | struct signal_struct *const sig = p->signal; |
624 | union cpu_time_count *exp = &timer->it.cpu.expires; | |
625 | ||
1da177e4 | 626 | /* |
f06febc9 | 627 | * For a process timer, set the cached expiration time. |
1da177e4 LT |
628 | */ |
629 | switch (CPUCLOCK_WHICH(timer->it_clock)) { | |
630 | default: | |
631 | BUG(); | |
632 | case CPUCLOCK_VIRT: | |
d1e3b6d1 | 633 | if (expires_le(sig->it[CPUCLOCK_VIRT].expires, |
42c4ab41 | 634 | exp->cpu)) |
1da177e4 | 635 | break; |
42c4ab41 | 636 | sig->cputime_expires.virt_exp = exp->cpu; |
f06febc9 | 637 | break; |
1da177e4 | 638 | case CPUCLOCK_PROF: |
d1e3b6d1 | 639 | if (expires_le(sig->it[CPUCLOCK_PROF].expires, |
42c4ab41 | 640 | exp->cpu)) |
1da177e4 | 641 | break; |
42c4ab41 | 642 | i = sig->rlim[RLIMIT_CPU].rlim_cur; |
1da177e4 | 643 | if (i != RLIM_INFINITY && |
42c4ab41 | 644 | i <= cputime_to_secs(exp->cpu)) |
1da177e4 | 645 | break; |
42c4ab41 | 646 | sig->cputime_expires.prof_exp = exp->cpu; |
f06febc9 | 647 | break; |
1da177e4 | 648 | case CPUCLOCK_SCHED: |
42c4ab41 | 649 | sig->cputime_expires.sched_exp = exp->sched; |
1da177e4 LT |
650 | break; |
651 | } | |
652 | } | |
653 | } | |
654 | ||
655 | spin_unlock(&p->sighand->siglock); | |
656 | } | |
657 | ||
658 | /* | |
659 | * The timer is locked, fire it and arrange for its reload. | |
660 | */ | |
661 | static void cpu_timer_fire(struct k_itimer *timer) | |
662 | { | |
663 | if (unlikely(timer->sigq == NULL)) { | |
664 | /* | |
665 | * This a special case for clock_nanosleep, | |
666 | * not a normal timer from sys_timer_create. | |
667 | */ | |
668 | wake_up_process(timer->it_process); | |
669 | timer->it.cpu.expires.sched = 0; | |
670 | } else if (timer->it.cpu.incr.sched == 0) { | |
671 | /* | |
672 | * One-shot timer. Clear it as soon as it's fired. | |
673 | */ | |
674 | posix_timer_event(timer, 0); | |
675 | timer->it.cpu.expires.sched = 0; | |
676 | } else if (posix_timer_event(timer, ++timer->it_requeue_pending)) { | |
677 | /* | |
678 | * The signal did not get queued because the signal | |
679 | * was ignored, so we won't get any callback to | |
680 | * reload the timer. But we need to keep it | |
681 | * ticking in case the signal is deliverable next time. | |
682 | */ | |
683 | posix_cpu_timer_schedule(timer); | |
684 | } | |
685 | } | |
686 | ||
3997ad31 PZ |
687 | /* |
688 | * Sample a process (thread group) timer for the given group_leader task. | |
689 | * Must be called with tasklist_lock held for reading. | |
690 | */ | |
691 | static int cpu_timer_sample_group(const clockid_t which_clock, | |
692 | struct task_struct *p, | |
693 | union cpu_time_count *cpu) | |
694 | { | |
695 | struct task_cputime cputime; | |
696 | ||
697 | thread_group_cputimer(p, &cputime); | |
698 | switch (CPUCLOCK_WHICH(which_clock)) { | |
699 | default: | |
700 | return -EINVAL; | |
701 | case CPUCLOCK_PROF: | |
702 | cpu->cpu = cputime_add(cputime.utime, cputime.stime); | |
703 | break; | |
704 | case CPUCLOCK_VIRT: | |
705 | cpu->cpu = cputime.utime; | |
706 | break; | |
707 | case CPUCLOCK_SCHED: | |
708 | cpu->sched = cputime.sum_exec_runtime + task_delta_exec(p); | |
709 | break; | |
710 | } | |
711 | return 0; | |
712 | } | |
713 | ||
1da177e4 LT |
714 | /* |
715 | * Guts of sys_timer_settime for CPU timers. | |
716 | * This is called with the timer locked and interrupts disabled. | |
717 | * If we return TIMER_RETRY, it's necessary to release the timer's lock | |
718 | * and try again. (This happens when the timer is in the middle of firing.) | |
719 | */ | |
720 | int posix_cpu_timer_set(struct k_itimer *timer, int flags, | |
721 | struct itimerspec *new, struct itimerspec *old) | |
722 | { | |
723 | struct task_struct *p = timer->it.cpu.task; | |
724 | union cpu_time_count old_expires, new_expires, val; | |
725 | int ret; | |
726 | ||
727 | if (unlikely(p == NULL)) { | |
728 | /* | |
729 | * Timer refers to a dead task's clock. | |
730 | */ | |
731 | return -ESRCH; | |
732 | } | |
733 | ||
734 | new_expires = timespec_to_sample(timer->it_clock, &new->it_value); | |
735 | ||
736 | read_lock(&tasklist_lock); | |
737 | /* | |
738 | * We need the tasklist_lock to protect against reaping that | |
739 | * clears p->signal. If p has just been reaped, we can no | |
740 | * longer get any information about it at all. | |
741 | */ | |
742 | if (unlikely(p->signal == NULL)) { | |
743 | read_unlock(&tasklist_lock); | |
744 | put_task_struct(p); | |
745 | timer->it.cpu.task = NULL; | |
746 | return -ESRCH; | |
747 | } | |
748 | ||
749 | /* | |
750 | * Disarm any old timer after extracting its expiry time. | |
751 | */ | |
752 | BUG_ON(!irqs_disabled()); | |
a69ac4a7 ON |
753 | |
754 | ret = 0; | |
1da177e4 LT |
755 | spin_lock(&p->sighand->siglock); |
756 | old_expires = timer->it.cpu.expires; | |
a69ac4a7 ON |
757 | if (unlikely(timer->it.cpu.firing)) { |
758 | timer->it.cpu.firing = -1; | |
759 | ret = TIMER_RETRY; | |
760 | } else | |
761 | list_del_init(&timer->it.cpu.entry); | |
1da177e4 LT |
762 | spin_unlock(&p->sighand->siglock); |
763 | ||
764 | /* | |
765 | * We need to sample the current value to convert the new | |
766 | * value from to relative and absolute, and to convert the | |
767 | * old value from absolute to relative. To set a process | |
768 | * timer, we need a sample to balance the thread expiry | |
769 | * times (in arm_timer). With an absolute time, we must | |
770 | * check if it's already passed. In short, we need a sample. | |
771 | */ | |
772 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
773 | cpu_clock_sample(timer->it_clock, p, &val); | |
774 | } else { | |
3997ad31 | 775 | cpu_timer_sample_group(timer->it_clock, p, &val); |
1da177e4 LT |
776 | } |
777 | ||
778 | if (old) { | |
779 | if (old_expires.sched == 0) { | |
780 | old->it_value.tv_sec = 0; | |
781 | old->it_value.tv_nsec = 0; | |
782 | } else { | |
783 | /* | |
784 | * Update the timer in case it has | |
785 | * overrun already. If it has, | |
786 | * we'll report it as having overrun | |
787 | * and with the next reloaded timer | |
788 | * already ticking, though we are | |
789 | * swallowing that pending | |
790 | * notification here to install the | |
791 | * new setting. | |
792 | */ | |
793 | bump_cpu_timer(timer, val); | |
794 | if (cpu_time_before(timer->it_clock, val, | |
795 | timer->it.cpu.expires)) { | |
796 | old_expires = cpu_time_sub( | |
797 | timer->it_clock, | |
798 | timer->it.cpu.expires, val); | |
799 | sample_to_timespec(timer->it_clock, | |
800 | old_expires, | |
801 | &old->it_value); | |
802 | } else { | |
803 | old->it_value.tv_nsec = 1; | |
804 | old->it_value.tv_sec = 0; | |
805 | } | |
806 | } | |
807 | } | |
808 | ||
a69ac4a7 | 809 | if (unlikely(ret)) { |
1da177e4 LT |
810 | /* |
811 | * We are colliding with the timer actually firing. | |
812 | * Punt after filling in the timer's old value, and | |
813 | * disable this firing since we are already reporting | |
814 | * it as an overrun (thanks to bump_cpu_timer above). | |
815 | */ | |
816 | read_unlock(&tasklist_lock); | |
1da177e4 LT |
817 | goto out; |
818 | } | |
819 | ||
820 | if (new_expires.sched != 0 && !(flags & TIMER_ABSTIME)) { | |
821 | cpu_time_add(timer->it_clock, &new_expires, val); | |
822 | } | |
823 | ||
824 | /* | |
825 | * Install the new expiry time (or zero). | |
826 | * For a timer with no notification action, we don't actually | |
827 | * arm the timer (we'll just fake it for timer_gettime). | |
828 | */ | |
829 | timer->it.cpu.expires = new_expires; | |
830 | if (new_expires.sched != 0 && | |
831 | (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE && | |
832 | cpu_time_before(timer->it_clock, val, new_expires)) { | |
833 | arm_timer(timer, val); | |
834 | } | |
835 | ||
836 | read_unlock(&tasklist_lock); | |
837 | ||
838 | /* | |
839 | * Install the new reload setting, and | |
840 | * set up the signal and overrun bookkeeping. | |
841 | */ | |
842 | timer->it.cpu.incr = timespec_to_sample(timer->it_clock, | |
843 | &new->it_interval); | |
844 | ||
845 | /* | |
846 | * This acts as a modification timestamp for the timer, | |
847 | * so any automatic reload attempt will punt on seeing | |
848 | * that we have reset the timer manually. | |
849 | */ | |
850 | timer->it_requeue_pending = (timer->it_requeue_pending + 2) & | |
851 | ~REQUEUE_PENDING; | |
852 | timer->it_overrun_last = 0; | |
853 | timer->it_overrun = -1; | |
854 | ||
855 | if (new_expires.sched != 0 && | |
856 | (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE && | |
857 | !cpu_time_before(timer->it_clock, val, new_expires)) { | |
858 | /* | |
859 | * The designated time already passed, so we notify | |
860 | * immediately, even if the thread never runs to | |
861 | * accumulate more time on this clock. | |
862 | */ | |
863 | cpu_timer_fire(timer); | |
864 | } | |
865 | ||
866 | ret = 0; | |
867 | out: | |
868 | if (old) { | |
869 | sample_to_timespec(timer->it_clock, | |
870 | timer->it.cpu.incr, &old->it_interval); | |
871 | } | |
872 | return ret; | |
873 | } | |
874 | ||
875 | void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) | |
876 | { | |
877 | union cpu_time_count now; | |
878 | struct task_struct *p = timer->it.cpu.task; | |
879 | int clear_dead; | |
880 | ||
881 | /* | |
882 | * Easy part: convert the reload time. | |
883 | */ | |
884 | sample_to_timespec(timer->it_clock, | |
885 | timer->it.cpu.incr, &itp->it_interval); | |
886 | ||
887 | if (timer->it.cpu.expires.sched == 0) { /* Timer not armed at all. */ | |
888 | itp->it_value.tv_sec = itp->it_value.tv_nsec = 0; | |
889 | return; | |
890 | } | |
891 | ||
892 | if (unlikely(p == NULL)) { | |
893 | /* | |
894 | * This task already died and the timer will never fire. | |
895 | * In this case, expires is actually the dead value. | |
896 | */ | |
897 | dead: | |
898 | sample_to_timespec(timer->it_clock, timer->it.cpu.expires, | |
899 | &itp->it_value); | |
900 | return; | |
901 | } | |
902 | ||
903 | /* | |
904 | * Sample the clock to take the difference with the expiry time. | |
905 | */ | |
906 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
907 | cpu_clock_sample(timer->it_clock, p, &now); | |
908 | clear_dead = p->exit_state; | |
909 | } else { | |
910 | read_lock(&tasklist_lock); | |
911 | if (unlikely(p->signal == NULL)) { | |
912 | /* | |
913 | * The process has been reaped. | |
914 | * We can't even collect a sample any more. | |
915 | * Call the timer disarmed, nothing else to do. | |
916 | */ | |
917 | put_task_struct(p); | |
918 | timer->it.cpu.task = NULL; | |
919 | timer->it.cpu.expires.sched = 0; | |
920 | read_unlock(&tasklist_lock); | |
921 | goto dead; | |
922 | } else { | |
3997ad31 | 923 | cpu_timer_sample_group(timer->it_clock, p, &now); |
1da177e4 LT |
924 | clear_dead = (unlikely(p->exit_state) && |
925 | thread_group_empty(p)); | |
926 | } | |
927 | read_unlock(&tasklist_lock); | |
928 | } | |
929 | ||
930 | if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) { | |
931 | if (timer->it.cpu.incr.sched == 0 && | |
932 | cpu_time_before(timer->it_clock, | |
933 | timer->it.cpu.expires, now)) { | |
934 | /* | |
935 | * Do-nothing timer expired and has no reload, | |
936 | * so it's as if it was never set. | |
937 | */ | |
938 | timer->it.cpu.expires.sched = 0; | |
939 | itp->it_value.tv_sec = itp->it_value.tv_nsec = 0; | |
940 | return; | |
941 | } | |
942 | /* | |
943 | * Account for any expirations and reloads that should | |
944 | * have happened. | |
945 | */ | |
946 | bump_cpu_timer(timer, now); | |
947 | } | |
948 | ||
949 | if (unlikely(clear_dead)) { | |
950 | /* | |
951 | * We've noticed that the thread is dead, but | |
952 | * not yet reaped. Take this opportunity to | |
953 | * drop our task ref. | |
954 | */ | |
955 | clear_dead_task(timer, now); | |
956 | goto dead; | |
957 | } | |
958 | ||
959 | if (cpu_time_before(timer->it_clock, now, timer->it.cpu.expires)) { | |
960 | sample_to_timespec(timer->it_clock, | |
961 | cpu_time_sub(timer->it_clock, | |
962 | timer->it.cpu.expires, now), | |
963 | &itp->it_value); | |
964 | } else { | |
965 | /* | |
966 | * The timer should have expired already, but the firing | |
967 | * hasn't taken place yet. Say it's just about to expire. | |
968 | */ | |
969 | itp->it_value.tv_nsec = 1; | |
970 | itp->it_value.tv_sec = 0; | |
971 | } | |
972 | } | |
973 | ||
974 | /* | |
975 | * Check for any per-thread CPU timers that have fired and move them off | |
976 | * the tsk->cpu_timers[N] list onto the firing list. Here we update the | |
977 | * tsk->it_*_expires values to reflect the remaining thread CPU timers. | |
978 | */ | |
979 | static void check_thread_timers(struct task_struct *tsk, | |
980 | struct list_head *firing) | |
981 | { | |
e80eda94 | 982 | int maxfire; |
1da177e4 | 983 | struct list_head *timers = tsk->cpu_timers; |
78f2c7db | 984 | struct signal_struct *const sig = tsk->signal; |
1da177e4 | 985 | |
e80eda94 | 986 | maxfire = 20; |
f06febc9 | 987 | tsk->cputime_expires.prof_exp = cputime_zero; |
1da177e4 | 988 | while (!list_empty(timers)) { |
b5e61818 | 989 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
990 | struct cpu_timer_list, |
991 | entry); | |
e80eda94 | 992 | if (!--maxfire || cputime_lt(prof_ticks(tsk), t->expires.cpu)) { |
f06febc9 | 993 | tsk->cputime_expires.prof_exp = t->expires.cpu; |
1da177e4 LT |
994 | break; |
995 | } | |
996 | t->firing = 1; | |
997 | list_move_tail(&t->entry, firing); | |
998 | } | |
999 | ||
1000 | ++timers; | |
e80eda94 | 1001 | maxfire = 20; |
f06febc9 | 1002 | tsk->cputime_expires.virt_exp = cputime_zero; |
1da177e4 | 1003 | while (!list_empty(timers)) { |
b5e61818 | 1004 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
1005 | struct cpu_timer_list, |
1006 | entry); | |
e80eda94 | 1007 | if (!--maxfire || cputime_lt(virt_ticks(tsk), t->expires.cpu)) { |
f06febc9 | 1008 | tsk->cputime_expires.virt_exp = t->expires.cpu; |
1da177e4 LT |
1009 | break; |
1010 | } | |
1011 | t->firing = 1; | |
1012 | list_move_tail(&t->entry, firing); | |
1013 | } | |
1014 | ||
1015 | ++timers; | |
e80eda94 | 1016 | maxfire = 20; |
f06febc9 | 1017 | tsk->cputime_expires.sched_exp = 0; |
1da177e4 | 1018 | while (!list_empty(timers)) { |
b5e61818 | 1019 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
1020 | struct cpu_timer_list, |
1021 | entry); | |
41b86e9c | 1022 | if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) { |
f06febc9 | 1023 | tsk->cputime_expires.sched_exp = t->expires.sched; |
1da177e4 LT |
1024 | break; |
1025 | } | |
1026 | t->firing = 1; | |
1027 | list_move_tail(&t->entry, firing); | |
1028 | } | |
78f2c7db PZ |
1029 | |
1030 | /* | |
1031 | * Check for the special case thread timers. | |
1032 | */ | |
1033 | if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) { | |
1034 | unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max; | |
1035 | unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur; | |
1036 | ||
5a52dd50 PZ |
1037 | if (hard != RLIM_INFINITY && |
1038 | tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { | |
78f2c7db PZ |
1039 | /* |
1040 | * At the hard limit, we just die. | |
1041 | * No need to calculate anything else now. | |
1042 | */ | |
1043 | __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); | |
1044 | return; | |
1045 | } | |
1046 | if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) { | |
1047 | /* | |
1048 | * At the soft limit, send a SIGXCPU every second. | |
1049 | */ | |
1050 | if (sig->rlim[RLIMIT_RTTIME].rlim_cur | |
1051 | < sig->rlim[RLIMIT_RTTIME].rlim_max) { | |
1052 | sig->rlim[RLIMIT_RTTIME].rlim_cur += | |
1053 | USEC_PER_SEC; | |
1054 | } | |
81d50bb2 HS |
1055 | printk(KERN_INFO |
1056 | "RT Watchdog Timeout: %s[%d]\n", | |
1057 | tsk->comm, task_pid_nr(tsk)); | |
78f2c7db PZ |
1058 | __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); |
1059 | } | |
1060 | } | |
1da177e4 LT |
1061 | } |
1062 | ||
3fccfd67 PZ |
1063 | static void stop_process_timers(struct task_struct *tsk) |
1064 | { | |
1065 | struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; | |
1066 | unsigned long flags; | |
1067 | ||
1068 | if (!cputimer->running) | |
1069 | return; | |
1070 | ||
1071 | spin_lock_irqsave(&cputimer->lock, flags); | |
1072 | cputimer->running = 0; | |
1073 | spin_unlock_irqrestore(&cputimer->lock, flags); | |
1074 | } | |
1075 | ||
8356b5f9 SG |
1076 | static u32 onecputick; |
1077 | ||
42c4ab41 SG |
1078 | static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, |
1079 | cputime_t *expires, cputime_t cur_time, int signo) | |
1080 | { | |
1081 | if (cputime_eq(it->expires, cputime_zero)) | |
1082 | return; | |
1083 | ||
1084 | if (cputime_ge(cur_time, it->expires)) { | |
8356b5f9 SG |
1085 | if (!cputime_eq(it->incr, cputime_zero)) { |
1086 | it->expires = cputime_add(it->expires, it->incr); | |
1087 | it->error += it->incr_error; | |
1088 | if (it->error >= onecputick) { | |
1089 | it->expires = cputime_sub(it->expires, | |
a42548a1 | 1090 | cputime_one_jiffy); |
8356b5f9 SG |
1091 | it->error -= onecputick; |
1092 | } | |
3f0a525e | 1093 | } else { |
8356b5f9 | 1094 | it->expires = cputime_zero; |
3f0a525e | 1095 | } |
42c4ab41 | 1096 | |
3f0a525e XG |
1097 | trace_itimer_expire(signo == SIGPROF ? |
1098 | ITIMER_PROF : ITIMER_VIRTUAL, | |
1099 | tsk->signal->leader_pid, cur_time); | |
42c4ab41 SG |
1100 | __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); |
1101 | } | |
1102 | ||
1103 | if (!cputime_eq(it->expires, cputime_zero) && | |
1104 | (cputime_eq(*expires, cputime_zero) || | |
1105 | cputime_lt(it->expires, *expires))) { | |
1106 | *expires = it->expires; | |
1107 | } | |
1108 | } | |
1109 | ||
1da177e4 LT |
1110 | /* |
1111 | * Check for any per-thread CPU timers that have fired and move them | |
1112 | * off the tsk->*_timers list onto the firing list. Per-thread timers | |
1113 | * have already been taken off. | |
1114 | */ | |
1115 | static void check_process_timers(struct task_struct *tsk, | |
1116 | struct list_head *firing) | |
1117 | { | |
e80eda94 | 1118 | int maxfire; |
1da177e4 | 1119 | struct signal_struct *const sig = tsk->signal; |
f06febc9 | 1120 | cputime_t utime, ptime, virt_expires, prof_expires; |
41b86e9c | 1121 | unsigned long long sum_sched_runtime, sched_expires; |
1da177e4 | 1122 | struct list_head *timers = sig->cpu_timers; |
f06febc9 | 1123 | struct task_cputime cputime; |
1da177e4 LT |
1124 | |
1125 | /* | |
1126 | * Don't sample the current process CPU clocks if there are no timers. | |
1127 | */ | |
1128 | if (list_empty(&timers[CPUCLOCK_PROF]) && | |
42c4ab41 | 1129 | cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) && |
1da177e4 LT |
1130 | sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY && |
1131 | list_empty(&timers[CPUCLOCK_VIRT]) && | |
42c4ab41 | 1132 | cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && |
4cd4c1b4 PZ |
1133 | list_empty(&timers[CPUCLOCK_SCHED])) { |
1134 | stop_process_timers(tsk); | |
1da177e4 | 1135 | return; |
4cd4c1b4 | 1136 | } |
1da177e4 LT |
1137 | |
1138 | /* | |
1139 | * Collect the current process totals. | |
1140 | */ | |
4cd4c1b4 | 1141 | thread_group_cputimer(tsk, &cputime); |
f06febc9 FM |
1142 | utime = cputime.utime; |
1143 | ptime = cputime_add(utime, cputime.stime); | |
1144 | sum_sched_runtime = cputime.sum_exec_runtime; | |
e80eda94 | 1145 | maxfire = 20; |
1da177e4 LT |
1146 | prof_expires = cputime_zero; |
1147 | while (!list_empty(timers)) { | |
ee7dd205 | 1148 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1149 | struct cpu_timer_list, |
1150 | entry); | |
ee7dd205 WC |
1151 | if (!--maxfire || cputime_lt(ptime, tl->expires.cpu)) { |
1152 | prof_expires = tl->expires.cpu; | |
1da177e4 LT |
1153 | break; |
1154 | } | |
ee7dd205 WC |
1155 | tl->firing = 1; |
1156 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1157 | } |
1158 | ||
1159 | ++timers; | |
e80eda94 | 1160 | maxfire = 20; |
1da177e4 LT |
1161 | virt_expires = cputime_zero; |
1162 | while (!list_empty(timers)) { | |
ee7dd205 | 1163 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1164 | struct cpu_timer_list, |
1165 | entry); | |
ee7dd205 WC |
1166 | if (!--maxfire || cputime_lt(utime, tl->expires.cpu)) { |
1167 | virt_expires = tl->expires.cpu; | |
1da177e4 LT |
1168 | break; |
1169 | } | |
ee7dd205 WC |
1170 | tl->firing = 1; |
1171 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1172 | } |
1173 | ||
1174 | ++timers; | |
e80eda94 | 1175 | maxfire = 20; |
1da177e4 LT |
1176 | sched_expires = 0; |
1177 | while (!list_empty(timers)) { | |
ee7dd205 | 1178 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1179 | struct cpu_timer_list, |
1180 | entry); | |
ee7dd205 WC |
1181 | if (!--maxfire || sum_sched_runtime < tl->expires.sched) { |
1182 | sched_expires = tl->expires.sched; | |
1da177e4 LT |
1183 | break; |
1184 | } | |
ee7dd205 WC |
1185 | tl->firing = 1; |
1186 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1187 | } |
1188 | ||
1189 | /* | |
1190 | * Check for the special case process timers. | |
1191 | */ | |
42c4ab41 SG |
1192 | check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime, |
1193 | SIGPROF); | |
1194 | check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime, | |
1195 | SIGVTALRM); | |
1196 | ||
1da177e4 LT |
1197 | if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { |
1198 | unsigned long psecs = cputime_to_secs(ptime); | |
1199 | cputime_t x; | |
1200 | if (psecs >= sig->rlim[RLIMIT_CPU].rlim_max) { | |
1201 | /* | |
1202 | * At the hard limit, we just die. | |
1203 | * No need to calculate anything else now. | |
1204 | */ | |
1205 | __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); | |
1206 | return; | |
1207 | } | |
1208 | if (psecs >= sig->rlim[RLIMIT_CPU].rlim_cur) { | |
1209 | /* | |
1210 | * At the soft limit, send a SIGXCPU every second. | |
1211 | */ | |
1212 | __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); | |
1213 | if (sig->rlim[RLIMIT_CPU].rlim_cur | |
1214 | < sig->rlim[RLIMIT_CPU].rlim_max) { | |
1215 | sig->rlim[RLIMIT_CPU].rlim_cur++; | |
1216 | } | |
1217 | } | |
1218 | x = secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur); | |
1219 | if (cputime_eq(prof_expires, cputime_zero) || | |
1220 | cputime_lt(x, prof_expires)) { | |
1221 | prof_expires = x; | |
1222 | } | |
1223 | } | |
1224 | ||
f06febc9 FM |
1225 | if (!cputime_eq(prof_expires, cputime_zero) && |
1226 | (cputime_eq(sig->cputime_expires.prof_exp, cputime_zero) || | |
1227 | cputime_gt(sig->cputime_expires.prof_exp, prof_expires))) | |
1228 | sig->cputime_expires.prof_exp = prof_expires; | |
1229 | if (!cputime_eq(virt_expires, cputime_zero) && | |
1230 | (cputime_eq(sig->cputime_expires.virt_exp, cputime_zero) || | |
1231 | cputime_gt(sig->cputime_expires.virt_exp, virt_expires))) | |
1232 | sig->cputime_expires.virt_exp = virt_expires; | |
1233 | if (sched_expires != 0 && | |
1234 | (sig->cputime_expires.sched_exp == 0 || | |
1235 | sig->cputime_expires.sched_exp > sched_expires)) | |
1236 | sig->cputime_expires.sched_exp = sched_expires; | |
1da177e4 LT |
1237 | } |
1238 | ||
1239 | /* | |
1240 | * This is called from the signal code (via do_schedule_next_timer) | |
1241 | * when the last timer signal was delivered and we have to reload the timer. | |
1242 | */ | |
1243 | void posix_cpu_timer_schedule(struct k_itimer *timer) | |
1244 | { | |
1245 | struct task_struct *p = timer->it.cpu.task; | |
1246 | union cpu_time_count now; | |
1247 | ||
1248 | if (unlikely(p == NULL)) | |
1249 | /* | |
1250 | * The task was cleaned up already, no future firings. | |
1251 | */ | |
708f430d | 1252 | goto out; |
1da177e4 LT |
1253 | |
1254 | /* | |
1255 | * Fetch the current sample and update the timer's expiry time. | |
1256 | */ | |
1257 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
1258 | cpu_clock_sample(timer->it_clock, p, &now); | |
1259 | bump_cpu_timer(timer, now); | |
1260 | if (unlikely(p->exit_state)) { | |
1261 | clear_dead_task(timer, now); | |
708f430d | 1262 | goto out; |
1da177e4 LT |
1263 | } |
1264 | read_lock(&tasklist_lock); /* arm_timer needs it. */ | |
1265 | } else { | |
1266 | read_lock(&tasklist_lock); | |
1267 | if (unlikely(p->signal == NULL)) { | |
1268 | /* | |
1269 | * The process has been reaped. | |
1270 | * We can't even collect a sample any more. | |
1271 | */ | |
1272 | put_task_struct(p); | |
1273 | timer->it.cpu.task = p = NULL; | |
1274 | timer->it.cpu.expires.sched = 0; | |
708f430d | 1275 | goto out_unlock; |
1da177e4 LT |
1276 | } else if (unlikely(p->exit_state) && thread_group_empty(p)) { |
1277 | /* | |
1278 | * We've noticed that the thread is dead, but | |
1279 | * not yet reaped. Take this opportunity to | |
1280 | * drop our task ref. | |
1281 | */ | |
1282 | clear_dead_task(timer, now); | |
708f430d | 1283 | goto out_unlock; |
1da177e4 | 1284 | } |
3997ad31 | 1285 | cpu_timer_sample_group(timer->it_clock, p, &now); |
1da177e4 LT |
1286 | bump_cpu_timer(timer, now); |
1287 | /* Leave the tasklist_lock locked for the call below. */ | |
1288 | } | |
1289 | ||
1290 | /* | |
1291 | * Now re-arm for the new expiry time. | |
1292 | */ | |
1293 | arm_timer(timer, now); | |
1294 | ||
708f430d | 1295 | out_unlock: |
1da177e4 | 1296 | read_unlock(&tasklist_lock); |
708f430d RM |
1297 | |
1298 | out: | |
1299 | timer->it_overrun_last = timer->it_overrun; | |
1300 | timer->it_overrun = -1; | |
1301 | ++timer->it_requeue_pending; | |
1da177e4 LT |
1302 | } |
1303 | ||
f06febc9 FM |
1304 | /** |
1305 | * task_cputime_zero - Check a task_cputime struct for all zero fields. | |
1306 | * | |
1307 | * @cputime: The struct to compare. | |
1308 | * | |
1309 | * Checks @cputime to see if all fields are zero. Returns true if all fields | |
1310 | * are zero, false if any field is nonzero. | |
1311 | */ | |
1312 | static inline int task_cputime_zero(const struct task_cputime *cputime) | |
1313 | { | |
1314 | if (cputime_eq(cputime->utime, cputime_zero) && | |
1315 | cputime_eq(cputime->stime, cputime_zero) && | |
1316 | cputime->sum_exec_runtime == 0) | |
1317 | return 1; | |
1318 | return 0; | |
1319 | } | |
1320 | ||
1321 | /** | |
1322 | * task_cputime_expired - Compare two task_cputime entities. | |
1323 | * | |
1324 | * @sample: The task_cputime structure to be checked for expiration. | |
1325 | * @expires: Expiration times, against which @sample will be checked. | |
1326 | * | |
1327 | * Checks @sample against @expires to see if any field of @sample has expired. | |
1328 | * Returns true if any field of the former is greater than the corresponding | |
1329 | * field of the latter if the latter field is set. Otherwise returns false. | |
1330 | */ | |
1331 | static inline int task_cputime_expired(const struct task_cputime *sample, | |
1332 | const struct task_cputime *expires) | |
1333 | { | |
1334 | if (!cputime_eq(expires->utime, cputime_zero) && | |
1335 | cputime_ge(sample->utime, expires->utime)) | |
1336 | return 1; | |
1337 | if (!cputime_eq(expires->stime, cputime_zero) && | |
1338 | cputime_ge(cputime_add(sample->utime, sample->stime), | |
1339 | expires->stime)) | |
1340 | return 1; | |
1341 | if (expires->sum_exec_runtime != 0 && | |
1342 | sample->sum_exec_runtime >= expires->sum_exec_runtime) | |
1343 | return 1; | |
1344 | return 0; | |
1345 | } | |
1346 | ||
1347 | /** | |
1348 | * fastpath_timer_check - POSIX CPU timers fast path. | |
1349 | * | |
1350 | * @tsk: The task (thread) being checked. | |
f06febc9 | 1351 | * |
bb34d92f FM |
1352 | * Check the task and thread group timers. If both are zero (there are no |
1353 | * timers set) return false. Otherwise snapshot the task and thread group | |
1354 | * timers and compare them with the corresponding expiration times. Return | |
1355 | * true if a timer has expired, else return false. | |
f06febc9 | 1356 | */ |
bb34d92f | 1357 | static inline int fastpath_timer_check(struct task_struct *tsk) |
f06febc9 | 1358 | { |
ad133ba3 | 1359 | struct signal_struct *sig; |
bb34d92f | 1360 | |
ad133ba3 ON |
1361 | /* tsk == current, ensure it is safe to use ->signal/sighand */ |
1362 | if (unlikely(tsk->exit_state)) | |
f06febc9 | 1363 | return 0; |
bb34d92f FM |
1364 | |
1365 | if (!task_cputime_zero(&tsk->cputime_expires)) { | |
1366 | struct task_cputime task_sample = { | |
1367 | .utime = tsk->utime, | |
1368 | .stime = tsk->stime, | |
1369 | .sum_exec_runtime = tsk->se.sum_exec_runtime | |
1370 | }; | |
1371 | ||
1372 | if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) | |
1373 | return 1; | |
1374 | } | |
ad133ba3 ON |
1375 | |
1376 | sig = tsk->signal; | |
bb34d92f FM |
1377 | if (!task_cputime_zero(&sig->cputime_expires)) { |
1378 | struct task_cputime group_sample; | |
1379 | ||
4cd4c1b4 | 1380 | thread_group_cputimer(tsk, &group_sample); |
bb34d92f FM |
1381 | if (task_cputime_expired(&group_sample, &sig->cputime_expires)) |
1382 | return 1; | |
1383 | } | |
37bebc70 ON |
1384 | |
1385 | return sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY; | |
f06febc9 FM |
1386 | } |
1387 | ||
1da177e4 LT |
1388 | /* |
1389 | * This is called from the timer interrupt handler. The irq handler has | |
1390 | * already updated our counts. We need to check if any timers fire now. | |
1391 | * Interrupts are disabled. | |
1392 | */ | |
1393 | void run_posix_cpu_timers(struct task_struct *tsk) | |
1394 | { | |
1395 | LIST_HEAD(firing); | |
1396 | struct k_itimer *timer, *next; | |
1397 | ||
1398 | BUG_ON(!irqs_disabled()); | |
1399 | ||
1da177e4 | 1400 | /* |
f06febc9 | 1401 | * The fast path checks that there are no expired thread or thread |
bb34d92f | 1402 | * group timers. If that's so, just return. |
1da177e4 | 1403 | */ |
bb34d92f | 1404 | if (!fastpath_timer_check(tsk)) |
f06febc9 | 1405 | return; |
5ce73a4a | 1406 | |
bb34d92f FM |
1407 | spin_lock(&tsk->sighand->siglock); |
1408 | /* | |
1409 | * Here we take off tsk->signal->cpu_timers[N] and | |
1410 | * tsk->cpu_timers[N] all the timers that are firing, and | |
1411 | * put them on the firing list. | |
1412 | */ | |
1413 | check_thread_timers(tsk, &firing); | |
1414 | check_process_timers(tsk, &firing); | |
1da177e4 | 1415 | |
bb34d92f FM |
1416 | /* |
1417 | * We must release these locks before taking any timer's lock. | |
1418 | * There is a potential race with timer deletion here, as the | |
1419 | * siglock now protects our private firing list. We have set | |
1420 | * the firing flag in each timer, so that a deletion attempt | |
1421 | * that gets the timer lock before we do will give it up and | |
1422 | * spin until we've taken care of that timer below. | |
1423 | */ | |
1424 | spin_unlock(&tsk->sighand->siglock); | |
1da177e4 LT |
1425 | |
1426 | /* | |
1427 | * Now that all the timers on our list have the firing flag, | |
1428 | * noone will touch their list entries but us. We'll take | |
1429 | * each timer's lock before clearing its firing flag, so no | |
1430 | * timer call will interfere. | |
1431 | */ | |
1432 | list_for_each_entry_safe(timer, next, &firing, it.cpu.entry) { | |
6e85c5ba HS |
1433 | int cpu_firing; |
1434 | ||
1da177e4 LT |
1435 | spin_lock(&timer->it_lock); |
1436 | list_del_init(&timer->it.cpu.entry); | |
6e85c5ba | 1437 | cpu_firing = timer->it.cpu.firing; |
1da177e4 LT |
1438 | timer->it.cpu.firing = 0; |
1439 | /* | |
1440 | * The firing flag is -1 if we collided with a reset | |
1441 | * of the timer, which already reported this | |
1442 | * almost-firing as an overrun. So don't generate an event. | |
1443 | */ | |
6e85c5ba | 1444 | if (likely(cpu_firing >= 0)) |
1da177e4 | 1445 | cpu_timer_fire(timer); |
1da177e4 LT |
1446 | spin_unlock(&timer->it_lock); |
1447 | } | |
1448 | } | |
1449 | ||
1450 | /* | |
1451 | * Set one of the process-wide special case CPU timers. | |
f06febc9 FM |
1452 | * The tsk->sighand->siglock must be held by the caller. |
1453 | * The *newval argument is relative and we update it to be absolute, *oldval | |
1454 | * is absolute and we update it to be relative. | |
1da177e4 LT |
1455 | */ |
1456 | void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, | |
1457 | cputime_t *newval, cputime_t *oldval) | |
1458 | { | |
1459 | union cpu_time_count now; | |
1460 | struct list_head *head; | |
1461 | ||
1462 | BUG_ON(clock_idx == CPUCLOCK_SCHED); | |
4cd4c1b4 | 1463 | cpu_timer_sample_group(clock_idx, tsk, &now); |
1da177e4 LT |
1464 | |
1465 | if (oldval) { | |
1466 | if (!cputime_eq(*oldval, cputime_zero)) { | |
1467 | if (cputime_le(*oldval, now.cpu)) { | |
1468 | /* Just about to fire. */ | |
a42548a1 | 1469 | *oldval = cputime_one_jiffy; |
1da177e4 LT |
1470 | } else { |
1471 | *oldval = cputime_sub(*oldval, now.cpu); | |
1472 | } | |
1473 | } | |
1474 | ||
1475 | if (cputime_eq(*newval, cputime_zero)) | |
1476 | return; | |
1477 | *newval = cputime_add(*newval, now.cpu); | |
1478 | ||
1479 | /* | |
1480 | * If the RLIMIT_CPU timer will expire before the | |
1481 | * ITIMER_PROF timer, we have nothing else to do. | |
1482 | */ | |
1483 | if (tsk->signal->rlim[RLIMIT_CPU].rlim_cur | |
1484 | < cputime_to_secs(*newval)) | |
1485 | return; | |
1486 | } | |
1487 | ||
1488 | /* | |
1489 | * Check whether there are any process timers already set to fire | |
1490 | * before this one. If so, we don't have anything more to do. | |
1491 | */ | |
1492 | head = &tsk->signal->cpu_timers[clock_idx]; | |
1493 | if (list_empty(head) || | |
b5e61818 | 1494 | cputime_ge(list_first_entry(head, |
1da177e4 LT |
1495 | struct cpu_timer_list, entry)->expires.cpu, |
1496 | *newval)) { | |
f06febc9 FM |
1497 | switch (clock_idx) { |
1498 | case CPUCLOCK_PROF: | |
1499 | tsk->signal->cputime_expires.prof_exp = *newval; | |
1500 | break; | |
1501 | case CPUCLOCK_VIRT: | |
1502 | tsk->signal->cputime_expires.virt_exp = *newval; | |
1503 | break; | |
1504 | } | |
1da177e4 LT |
1505 | } |
1506 | } | |
1507 | ||
e4b76555 TA |
1508 | static int do_cpu_nanosleep(const clockid_t which_clock, int flags, |
1509 | struct timespec *rqtp, struct itimerspec *it) | |
1da177e4 | 1510 | { |
1da177e4 LT |
1511 | struct k_itimer timer; |
1512 | int error; | |
1513 | ||
1da177e4 LT |
1514 | /* |
1515 | * Set up a temporary timer and then wait for it to go off. | |
1516 | */ | |
1517 | memset(&timer, 0, sizeof timer); | |
1518 | spin_lock_init(&timer.it_lock); | |
1519 | timer.it_clock = which_clock; | |
1520 | timer.it_overrun = -1; | |
1521 | error = posix_cpu_timer_create(&timer); | |
1522 | timer.it_process = current; | |
1523 | if (!error) { | |
1da177e4 | 1524 | static struct itimerspec zero_it; |
e4b76555 TA |
1525 | |
1526 | memset(it, 0, sizeof *it); | |
1527 | it->it_value = *rqtp; | |
1da177e4 LT |
1528 | |
1529 | spin_lock_irq(&timer.it_lock); | |
e4b76555 | 1530 | error = posix_cpu_timer_set(&timer, flags, it, NULL); |
1da177e4 LT |
1531 | if (error) { |
1532 | spin_unlock_irq(&timer.it_lock); | |
1533 | return error; | |
1534 | } | |
1535 | ||
1536 | while (!signal_pending(current)) { | |
1537 | if (timer.it.cpu.expires.sched == 0) { | |
1538 | /* | |
1539 | * Our timer fired and was reset. | |
1540 | */ | |
1541 | spin_unlock_irq(&timer.it_lock); | |
1542 | return 0; | |
1543 | } | |
1544 | ||
1545 | /* | |
1546 | * Block until cpu_timer_fire (or a signal) wakes us. | |
1547 | */ | |
1548 | __set_current_state(TASK_INTERRUPTIBLE); | |
1549 | spin_unlock_irq(&timer.it_lock); | |
1550 | schedule(); | |
1551 | spin_lock_irq(&timer.it_lock); | |
1552 | } | |
1553 | ||
1554 | /* | |
1555 | * We were interrupted by a signal. | |
1556 | */ | |
1557 | sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp); | |
e4b76555 | 1558 | posix_cpu_timer_set(&timer, 0, &zero_it, it); |
1da177e4 LT |
1559 | spin_unlock_irq(&timer.it_lock); |
1560 | ||
e4b76555 | 1561 | if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) { |
1da177e4 LT |
1562 | /* |
1563 | * It actually did fire already. | |
1564 | */ | |
1565 | return 0; | |
1566 | } | |
1567 | ||
e4b76555 TA |
1568 | error = -ERESTART_RESTARTBLOCK; |
1569 | } | |
1570 | ||
1571 | return error; | |
1572 | } | |
1573 | ||
1574 | int posix_cpu_nsleep(const clockid_t which_clock, int flags, | |
1575 | struct timespec *rqtp, struct timespec __user *rmtp) | |
1576 | { | |
1577 | struct restart_block *restart_block = | |
1578 | ¤t_thread_info()->restart_block; | |
1579 | struct itimerspec it; | |
1580 | int error; | |
1581 | ||
1582 | /* | |
1583 | * Diagnose required errors first. | |
1584 | */ | |
1585 | if (CPUCLOCK_PERTHREAD(which_clock) && | |
1586 | (CPUCLOCK_PID(which_clock) == 0 || | |
1587 | CPUCLOCK_PID(which_clock) == current->pid)) | |
1588 | return -EINVAL; | |
1589 | ||
1590 | error = do_cpu_nanosleep(which_clock, flags, rqtp, &it); | |
1591 | ||
1592 | if (error == -ERESTART_RESTARTBLOCK) { | |
1593 | ||
1594 | if (flags & TIMER_ABSTIME) | |
1595 | return -ERESTARTNOHAND; | |
1da177e4 | 1596 | /* |
e4b76555 TA |
1597 | * Report back to the user the time still remaining. |
1598 | */ | |
1599 | if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) | |
1da177e4 LT |
1600 | return -EFAULT; |
1601 | ||
1711ef38 | 1602 | restart_block->fn = posix_cpu_nsleep_restart; |
1da177e4 | 1603 | restart_block->arg0 = which_clock; |
97735f25 | 1604 | restart_block->arg1 = (unsigned long) rmtp; |
1da177e4 LT |
1605 | restart_block->arg2 = rqtp->tv_sec; |
1606 | restart_block->arg3 = rqtp->tv_nsec; | |
1da177e4 | 1607 | } |
1da177e4 LT |
1608 | return error; |
1609 | } | |
1610 | ||
1711ef38 | 1611 | long posix_cpu_nsleep_restart(struct restart_block *restart_block) |
1da177e4 LT |
1612 | { |
1613 | clockid_t which_clock = restart_block->arg0; | |
97735f25 TG |
1614 | struct timespec __user *rmtp; |
1615 | struct timespec t; | |
e4b76555 TA |
1616 | struct itimerspec it; |
1617 | int error; | |
97735f25 TG |
1618 | |
1619 | rmtp = (struct timespec __user *) restart_block->arg1; | |
1620 | t.tv_sec = restart_block->arg2; | |
1621 | t.tv_nsec = restart_block->arg3; | |
1622 | ||
1da177e4 | 1623 | restart_block->fn = do_no_restart_syscall; |
e4b76555 TA |
1624 | error = do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t, &it); |
1625 | ||
1626 | if (error == -ERESTART_RESTARTBLOCK) { | |
1627 | /* | |
1628 | * Report back to the user the time still remaining. | |
1629 | */ | |
1630 | if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) | |
1631 | return -EFAULT; | |
1632 | ||
1633 | restart_block->fn = posix_cpu_nsleep_restart; | |
1634 | restart_block->arg0 = which_clock; | |
1635 | restart_block->arg1 = (unsigned long) rmtp; | |
1636 | restart_block->arg2 = t.tv_sec; | |
1637 | restart_block->arg3 = t.tv_nsec; | |
1638 | } | |
1639 | return error; | |
1640 | ||
1da177e4 LT |
1641 | } |
1642 | ||
1643 | ||
1644 | #define PROCESS_CLOCK MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED) | |
1645 | #define THREAD_CLOCK MAKE_THREAD_CPUCLOCK(0, CPUCLOCK_SCHED) | |
1646 | ||
a924b04d TG |
1647 | static int process_cpu_clock_getres(const clockid_t which_clock, |
1648 | struct timespec *tp) | |
1da177e4 LT |
1649 | { |
1650 | return posix_cpu_clock_getres(PROCESS_CLOCK, tp); | |
1651 | } | |
a924b04d TG |
1652 | static int process_cpu_clock_get(const clockid_t which_clock, |
1653 | struct timespec *tp) | |
1da177e4 LT |
1654 | { |
1655 | return posix_cpu_clock_get(PROCESS_CLOCK, tp); | |
1656 | } | |
1657 | static int process_cpu_timer_create(struct k_itimer *timer) | |
1658 | { | |
1659 | timer->it_clock = PROCESS_CLOCK; | |
1660 | return posix_cpu_timer_create(timer); | |
1661 | } | |
a924b04d | 1662 | static int process_cpu_nsleep(const clockid_t which_clock, int flags, |
97735f25 TG |
1663 | struct timespec *rqtp, |
1664 | struct timespec __user *rmtp) | |
1da177e4 | 1665 | { |
97735f25 | 1666 | return posix_cpu_nsleep(PROCESS_CLOCK, flags, rqtp, rmtp); |
1da177e4 | 1667 | } |
1711ef38 TA |
1668 | static long process_cpu_nsleep_restart(struct restart_block *restart_block) |
1669 | { | |
1670 | return -EINVAL; | |
1671 | } | |
a924b04d TG |
1672 | static int thread_cpu_clock_getres(const clockid_t which_clock, |
1673 | struct timespec *tp) | |
1da177e4 LT |
1674 | { |
1675 | return posix_cpu_clock_getres(THREAD_CLOCK, tp); | |
1676 | } | |
a924b04d TG |
1677 | static int thread_cpu_clock_get(const clockid_t which_clock, |
1678 | struct timespec *tp) | |
1da177e4 LT |
1679 | { |
1680 | return posix_cpu_clock_get(THREAD_CLOCK, tp); | |
1681 | } | |
1682 | static int thread_cpu_timer_create(struct k_itimer *timer) | |
1683 | { | |
1684 | timer->it_clock = THREAD_CLOCK; | |
1685 | return posix_cpu_timer_create(timer); | |
1686 | } | |
a924b04d | 1687 | static int thread_cpu_nsleep(const clockid_t which_clock, int flags, |
97735f25 | 1688 | struct timespec *rqtp, struct timespec __user *rmtp) |
1da177e4 LT |
1689 | { |
1690 | return -EINVAL; | |
1691 | } | |
1711ef38 TA |
1692 | static long thread_cpu_nsleep_restart(struct restart_block *restart_block) |
1693 | { | |
1694 | return -EINVAL; | |
1695 | } | |
1da177e4 LT |
1696 | |
1697 | static __init int init_posix_cpu_timers(void) | |
1698 | { | |
1699 | struct k_clock process = { | |
1700 | .clock_getres = process_cpu_clock_getres, | |
1701 | .clock_get = process_cpu_clock_get, | |
1702 | .clock_set = do_posix_clock_nosettime, | |
1703 | .timer_create = process_cpu_timer_create, | |
1704 | .nsleep = process_cpu_nsleep, | |
1711ef38 | 1705 | .nsleep_restart = process_cpu_nsleep_restart, |
1da177e4 LT |
1706 | }; |
1707 | struct k_clock thread = { | |
1708 | .clock_getres = thread_cpu_clock_getres, | |
1709 | .clock_get = thread_cpu_clock_get, | |
1710 | .clock_set = do_posix_clock_nosettime, | |
1711 | .timer_create = thread_cpu_timer_create, | |
1712 | .nsleep = thread_cpu_nsleep, | |
1711ef38 | 1713 | .nsleep_restart = thread_cpu_nsleep_restart, |
1da177e4 | 1714 | }; |
8356b5f9 | 1715 | struct timespec ts; |
1da177e4 LT |
1716 | |
1717 | register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); | |
1718 | register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); | |
1719 | ||
a42548a1 | 1720 | cputime_to_timespec(cputime_one_jiffy, &ts); |
8356b5f9 SG |
1721 | onecputick = ts.tv_nsec; |
1722 | WARN_ON(ts.tv_sec != 0); | |
1723 | ||
1da177e4 LT |
1724 | return 0; |
1725 | } | |
1726 | __initcall(init_posix_cpu_timers); |