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. | |
387 | * This is called from sys_timer_create with the new timer already locked. | |
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); | |
399 | new_timer->it.cpu.incr.sched = 0; | |
400 | new_timer->it.cpu.expires.sched = 0; | |
401 | ||
402 | read_lock(&tasklist_lock); | |
403 | if (CPUCLOCK_PERTHREAD(new_timer->it_clock)) { | |
404 | if (pid == 0) { | |
405 | p = current; | |
406 | } else { | |
8dc86af0 | 407 | p = find_task_by_vpid(pid); |
bac0abd6 | 408 | if (p && !same_thread_group(p, current)) |
1da177e4 LT |
409 | p = NULL; |
410 | } | |
411 | } else { | |
412 | if (pid == 0) { | |
413 | p = current->group_leader; | |
414 | } else { | |
8dc86af0 | 415 | p = find_task_by_vpid(pid); |
bac0abd6 | 416 | if (p && !thread_group_leader(p)) |
1da177e4 LT |
417 | p = NULL; |
418 | } | |
419 | } | |
420 | new_timer->it.cpu.task = p; | |
421 | if (p) { | |
422 | get_task_struct(p); | |
423 | } else { | |
424 | ret = -EINVAL; | |
425 | } | |
426 | read_unlock(&tasklist_lock); | |
427 | ||
428 | return ret; | |
429 | } | |
430 | ||
431 | /* | |
432 | * Clean up a CPU-clock timer that is about to be destroyed. | |
433 | * This is called from timer deletion with the timer already locked. | |
434 | * If we return TIMER_RETRY, it's necessary to release the timer's lock | |
435 | * and try again. (This happens when the timer is in the middle of firing.) | |
436 | */ | |
437 | int posix_cpu_timer_del(struct k_itimer *timer) | |
438 | { | |
439 | struct task_struct *p = timer->it.cpu.task; | |
108150ea | 440 | int ret = 0; |
1da177e4 | 441 | |
108150ea | 442 | if (likely(p != NULL)) { |
9465bee8 LT |
443 | read_lock(&tasklist_lock); |
444 | if (unlikely(p->signal == NULL)) { | |
445 | /* | |
446 | * We raced with the reaping of the task. | |
447 | * The deletion should have cleared us off the list. | |
448 | */ | |
449 | BUG_ON(!list_empty(&timer->it.cpu.entry)); | |
450 | } else { | |
9465bee8 | 451 | spin_lock(&p->sighand->siglock); |
108150ea ON |
452 | if (timer->it.cpu.firing) |
453 | ret = TIMER_RETRY; | |
454 | else | |
455 | list_del(&timer->it.cpu.entry); | |
9465bee8 LT |
456 | spin_unlock(&p->sighand->siglock); |
457 | } | |
458 | read_unlock(&tasklist_lock); | |
108150ea ON |
459 | |
460 | if (!ret) | |
461 | put_task_struct(p); | |
1da177e4 | 462 | } |
1da177e4 | 463 | |
108150ea | 464 | return ret; |
1da177e4 LT |
465 | } |
466 | ||
467 | /* | |
468 | * Clean out CPU timers still ticking when a thread exited. The task | |
469 | * pointer is cleared, and the expiry time is replaced with the residual | |
470 | * time for later timer_gettime calls to return. | |
471 | * This must be called with the siglock held. | |
472 | */ | |
473 | static void cleanup_timers(struct list_head *head, | |
474 | cputime_t utime, cputime_t stime, | |
41b86e9c | 475 | unsigned long long sum_exec_runtime) |
1da177e4 LT |
476 | { |
477 | struct cpu_timer_list *timer, *next; | |
478 | cputime_t ptime = cputime_add(utime, stime); | |
479 | ||
480 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 LT |
481 | list_del_init(&timer->entry); |
482 | if (cputime_lt(timer->expires.cpu, ptime)) { | |
483 | timer->expires.cpu = cputime_zero; | |
484 | } else { | |
485 | timer->expires.cpu = cputime_sub(timer->expires.cpu, | |
486 | ptime); | |
487 | } | |
488 | } | |
489 | ||
490 | ++head; | |
491 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 LT |
492 | list_del_init(&timer->entry); |
493 | if (cputime_lt(timer->expires.cpu, utime)) { | |
494 | timer->expires.cpu = cputime_zero; | |
495 | } else { | |
496 | timer->expires.cpu = cputime_sub(timer->expires.cpu, | |
497 | utime); | |
498 | } | |
499 | } | |
500 | ||
501 | ++head; | |
502 | list_for_each_entry_safe(timer, next, head, entry) { | |
1da177e4 | 503 | list_del_init(&timer->entry); |
41b86e9c | 504 | if (timer->expires.sched < sum_exec_runtime) { |
1da177e4 LT |
505 | timer->expires.sched = 0; |
506 | } else { | |
41b86e9c | 507 | timer->expires.sched -= sum_exec_runtime; |
1da177e4 LT |
508 | } |
509 | } | |
510 | } | |
511 | ||
512 | /* | |
513 | * These are both called with the siglock held, when the current thread | |
514 | * is being reaped. When the final (leader) thread in the group is reaped, | |
515 | * posix_cpu_timers_exit_group will be called after posix_cpu_timers_exit. | |
516 | */ | |
517 | void posix_cpu_timers_exit(struct task_struct *tsk) | |
518 | { | |
519 | cleanup_timers(tsk->cpu_timers, | |
41b86e9c | 520 | tsk->utime, tsk->stime, tsk->se.sum_exec_runtime); |
1da177e4 LT |
521 | |
522 | } | |
523 | void posix_cpu_timers_exit_group(struct task_struct *tsk) | |
524 | { | |
17d42c1c | 525 | struct signal_struct *const sig = tsk->signal; |
ca531a0a | 526 | |
f06febc9 | 527 | cleanup_timers(tsk->signal->cpu_timers, |
17d42c1c SG |
528 | cputime_add(tsk->utime, sig->utime), |
529 | cputime_add(tsk->stime, sig->stime), | |
530 | tsk->se.sum_exec_runtime + sig->sum_sched_runtime); | |
1da177e4 LT |
531 | } |
532 | ||
533 | static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) | |
534 | { | |
535 | /* | |
536 | * That's all for this thread or process. | |
537 | * We leave our residual in expires to be reported. | |
538 | */ | |
539 | put_task_struct(timer->it.cpu.task); | |
540 | timer->it.cpu.task = NULL; | |
541 | timer->it.cpu.expires = cpu_time_sub(timer->it_clock, | |
542 | timer->it.cpu.expires, | |
543 | now); | |
544 | } | |
545 | ||
d1e3b6d1 SG |
546 | static inline int expires_gt(cputime_t expires, cputime_t new_exp) |
547 | { | |
548 | return cputime_eq(expires, cputime_zero) || | |
549 | cputime_gt(expires, new_exp); | |
550 | } | |
551 | ||
552 | static inline int expires_le(cputime_t expires, cputime_t new_exp) | |
553 | { | |
554 | return !cputime_eq(expires, cputime_zero) && | |
555 | cputime_le(expires, new_exp); | |
556 | } | |
1da177e4 LT |
557 | /* |
558 | * Insert the timer on the appropriate list before any timers that | |
559 | * expire later. This must be called with the tasklist_lock held | |
560 | * for reading, and interrupts disabled. | |
561 | */ | |
562 | static void arm_timer(struct k_itimer *timer, union cpu_time_count now) | |
563 | { | |
564 | struct task_struct *p = timer->it.cpu.task; | |
565 | struct list_head *head, *listpos; | |
566 | struct cpu_timer_list *const nt = &timer->it.cpu; | |
567 | struct cpu_timer_list *next; | |
568 | unsigned long i; | |
569 | ||
570 | head = (CPUCLOCK_PERTHREAD(timer->it_clock) ? | |
571 | p->cpu_timers : p->signal->cpu_timers); | |
572 | head += CPUCLOCK_WHICH(timer->it_clock); | |
573 | ||
574 | BUG_ON(!irqs_disabled()); | |
575 | spin_lock(&p->sighand->siglock); | |
576 | ||
577 | listpos = head; | |
578 | if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) { | |
579 | list_for_each_entry(next, head, entry) { | |
70ab81c2 | 580 | if (next->expires.sched > nt->expires.sched) |
1da177e4 | 581 | break; |
70ab81c2 | 582 | listpos = &next->entry; |
1da177e4 LT |
583 | } |
584 | } else { | |
585 | list_for_each_entry(next, head, entry) { | |
70ab81c2 | 586 | if (cputime_gt(next->expires.cpu, nt->expires.cpu)) |
1da177e4 | 587 | break; |
70ab81c2 | 588 | listpos = &next->entry; |
1da177e4 LT |
589 | } |
590 | } | |
591 | list_add(&nt->entry, listpos); | |
592 | ||
593 | if (listpos == head) { | |
594 | /* | |
595 | * We are the new earliest-expiring timer. | |
596 | * If we are a thread timer, there can always | |
597 | * be a process timer telling us to stop earlier. | |
598 | */ | |
599 | ||
600 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
d1e3b6d1 SG |
601 | union cpu_time_count *exp = &nt->expires; |
602 | ||
1da177e4 LT |
603 | switch (CPUCLOCK_WHICH(timer->it_clock)) { |
604 | default: | |
605 | BUG(); | |
606 | case CPUCLOCK_PROF: | |
d1e3b6d1 SG |
607 | if (expires_gt(p->cputime_expires.prof_exp, |
608 | exp->cpu)) | |
609 | p->cputime_expires.prof_exp = exp->cpu; | |
1da177e4 LT |
610 | break; |
611 | case CPUCLOCK_VIRT: | |
d1e3b6d1 SG |
612 | if (expires_gt(p->cputime_expires.virt_exp, |
613 | exp->cpu)) | |
614 | p->cputime_expires.virt_exp = exp->cpu; | |
1da177e4 LT |
615 | break; |
616 | case CPUCLOCK_SCHED: | |
f06febc9 | 617 | if (p->cputime_expires.sched_exp == 0 || |
d1e3b6d1 | 618 | p->cputime_expires.sched_exp > exp->sched) |
f06febc9 | 619 | p->cputime_expires.sched_exp = |
d1e3b6d1 | 620 | exp->sched; |
1da177e4 LT |
621 | break; |
622 | } | |
623 | } else { | |
42c4ab41 SG |
624 | struct signal_struct *const sig = p->signal; |
625 | union cpu_time_count *exp = &timer->it.cpu.expires; | |
626 | ||
1da177e4 | 627 | /* |
f06febc9 | 628 | * For a process timer, set the cached expiration time. |
1da177e4 LT |
629 | */ |
630 | switch (CPUCLOCK_WHICH(timer->it_clock)) { | |
631 | default: | |
632 | BUG(); | |
633 | case CPUCLOCK_VIRT: | |
d1e3b6d1 | 634 | if (expires_le(sig->it[CPUCLOCK_VIRT].expires, |
42c4ab41 | 635 | exp->cpu)) |
1da177e4 | 636 | break; |
42c4ab41 | 637 | sig->cputime_expires.virt_exp = exp->cpu; |
f06febc9 | 638 | break; |
1da177e4 | 639 | case CPUCLOCK_PROF: |
d1e3b6d1 | 640 | if (expires_le(sig->it[CPUCLOCK_PROF].expires, |
42c4ab41 | 641 | exp->cpu)) |
1da177e4 | 642 | break; |
42c4ab41 | 643 | i = sig->rlim[RLIMIT_CPU].rlim_cur; |
1da177e4 | 644 | if (i != RLIM_INFINITY && |
42c4ab41 | 645 | i <= cputime_to_secs(exp->cpu)) |
1da177e4 | 646 | break; |
42c4ab41 | 647 | sig->cputime_expires.prof_exp = exp->cpu; |
f06febc9 | 648 | break; |
1da177e4 | 649 | case CPUCLOCK_SCHED: |
42c4ab41 | 650 | sig->cputime_expires.sched_exp = exp->sched; |
1da177e4 LT |
651 | break; |
652 | } | |
653 | } | |
654 | } | |
655 | ||
656 | spin_unlock(&p->sighand->siglock); | |
657 | } | |
658 | ||
659 | /* | |
660 | * The timer is locked, fire it and arrange for its reload. | |
661 | */ | |
662 | static void cpu_timer_fire(struct k_itimer *timer) | |
663 | { | |
664 | if (unlikely(timer->sigq == NULL)) { | |
665 | /* | |
666 | * This a special case for clock_nanosleep, | |
667 | * not a normal timer from sys_timer_create. | |
668 | */ | |
669 | wake_up_process(timer->it_process); | |
670 | timer->it.cpu.expires.sched = 0; | |
671 | } else if (timer->it.cpu.incr.sched == 0) { | |
672 | /* | |
673 | * One-shot timer. Clear it as soon as it's fired. | |
674 | */ | |
675 | posix_timer_event(timer, 0); | |
676 | timer->it.cpu.expires.sched = 0; | |
677 | } else if (posix_timer_event(timer, ++timer->it_requeue_pending)) { | |
678 | /* | |
679 | * The signal did not get queued because the signal | |
680 | * was ignored, so we won't get any callback to | |
681 | * reload the timer. But we need to keep it | |
682 | * ticking in case the signal is deliverable next time. | |
683 | */ | |
684 | posix_cpu_timer_schedule(timer); | |
685 | } | |
686 | } | |
687 | ||
3997ad31 PZ |
688 | /* |
689 | * Sample a process (thread group) timer for the given group_leader task. | |
690 | * Must be called with tasklist_lock held for reading. | |
691 | */ | |
692 | static int cpu_timer_sample_group(const clockid_t which_clock, | |
693 | struct task_struct *p, | |
694 | union cpu_time_count *cpu) | |
695 | { | |
696 | struct task_cputime cputime; | |
697 | ||
698 | thread_group_cputimer(p, &cputime); | |
699 | switch (CPUCLOCK_WHICH(which_clock)) { | |
700 | default: | |
701 | return -EINVAL; | |
702 | case CPUCLOCK_PROF: | |
703 | cpu->cpu = cputime_add(cputime.utime, cputime.stime); | |
704 | break; | |
705 | case CPUCLOCK_VIRT: | |
706 | cpu->cpu = cputime.utime; | |
707 | break; | |
708 | case CPUCLOCK_SCHED: | |
709 | cpu->sched = cputime.sum_exec_runtime + task_delta_exec(p); | |
710 | break; | |
711 | } | |
712 | return 0; | |
713 | } | |
714 | ||
1da177e4 LT |
715 | /* |
716 | * Guts of sys_timer_settime for CPU timers. | |
717 | * This is called with the timer locked and interrupts disabled. | |
718 | * If we return TIMER_RETRY, it's necessary to release the timer's lock | |
719 | * and try again. (This happens when the timer is in the middle of firing.) | |
720 | */ | |
721 | int posix_cpu_timer_set(struct k_itimer *timer, int flags, | |
722 | struct itimerspec *new, struct itimerspec *old) | |
723 | { | |
724 | struct task_struct *p = timer->it.cpu.task; | |
725 | union cpu_time_count old_expires, new_expires, val; | |
726 | int ret; | |
727 | ||
728 | if (unlikely(p == NULL)) { | |
729 | /* | |
730 | * Timer refers to a dead task's clock. | |
731 | */ | |
732 | return -ESRCH; | |
733 | } | |
734 | ||
735 | new_expires = timespec_to_sample(timer->it_clock, &new->it_value); | |
736 | ||
737 | read_lock(&tasklist_lock); | |
738 | /* | |
739 | * We need the tasklist_lock to protect against reaping that | |
740 | * clears p->signal. If p has just been reaped, we can no | |
741 | * longer get any information about it at all. | |
742 | */ | |
743 | if (unlikely(p->signal == NULL)) { | |
744 | read_unlock(&tasklist_lock); | |
745 | put_task_struct(p); | |
746 | timer->it.cpu.task = NULL; | |
747 | return -ESRCH; | |
748 | } | |
749 | ||
750 | /* | |
751 | * Disarm any old timer after extracting its expiry time. | |
752 | */ | |
753 | BUG_ON(!irqs_disabled()); | |
a69ac4a7 ON |
754 | |
755 | ret = 0; | |
1da177e4 LT |
756 | spin_lock(&p->sighand->siglock); |
757 | old_expires = timer->it.cpu.expires; | |
a69ac4a7 ON |
758 | if (unlikely(timer->it.cpu.firing)) { |
759 | timer->it.cpu.firing = -1; | |
760 | ret = TIMER_RETRY; | |
761 | } else | |
762 | list_del_init(&timer->it.cpu.entry); | |
1da177e4 LT |
763 | spin_unlock(&p->sighand->siglock); |
764 | ||
765 | /* | |
766 | * We need to sample the current value to convert the new | |
767 | * value from to relative and absolute, and to convert the | |
768 | * old value from absolute to relative. To set a process | |
769 | * timer, we need a sample to balance the thread expiry | |
770 | * times (in arm_timer). With an absolute time, we must | |
771 | * check if it's already passed. In short, we need a sample. | |
772 | */ | |
773 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
774 | cpu_clock_sample(timer->it_clock, p, &val); | |
775 | } else { | |
3997ad31 | 776 | cpu_timer_sample_group(timer->it_clock, p, &val); |
1da177e4 LT |
777 | } |
778 | ||
779 | if (old) { | |
780 | if (old_expires.sched == 0) { | |
781 | old->it_value.tv_sec = 0; | |
782 | old->it_value.tv_nsec = 0; | |
783 | } else { | |
784 | /* | |
785 | * Update the timer in case it has | |
786 | * overrun already. If it has, | |
787 | * we'll report it as having overrun | |
788 | * and with the next reloaded timer | |
789 | * already ticking, though we are | |
790 | * swallowing that pending | |
791 | * notification here to install the | |
792 | * new setting. | |
793 | */ | |
794 | bump_cpu_timer(timer, val); | |
795 | if (cpu_time_before(timer->it_clock, val, | |
796 | timer->it.cpu.expires)) { | |
797 | old_expires = cpu_time_sub( | |
798 | timer->it_clock, | |
799 | timer->it.cpu.expires, val); | |
800 | sample_to_timespec(timer->it_clock, | |
801 | old_expires, | |
802 | &old->it_value); | |
803 | } else { | |
804 | old->it_value.tv_nsec = 1; | |
805 | old->it_value.tv_sec = 0; | |
806 | } | |
807 | } | |
808 | } | |
809 | ||
a69ac4a7 | 810 | if (unlikely(ret)) { |
1da177e4 LT |
811 | /* |
812 | * We are colliding with the timer actually firing. | |
813 | * Punt after filling in the timer's old value, and | |
814 | * disable this firing since we are already reporting | |
815 | * it as an overrun (thanks to bump_cpu_timer above). | |
816 | */ | |
817 | read_unlock(&tasklist_lock); | |
1da177e4 LT |
818 | goto out; |
819 | } | |
820 | ||
821 | if (new_expires.sched != 0 && !(flags & TIMER_ABSTIME)) { | |
822 | cpu_time_add(timer->it_clock, &new_expires, val); | |
823 | } | |
824 | ||
825 | /* | |
826 | * Install the new expiry time (or zero). | |
827 | * For a timer with no notification action, we don't actually | |
828 | * arm the timer (we'll just fake it for timer_gettime). | |
829 | */ | |
830 | timer->it.cpu.expires = new_expires; | |
831 | if (new_expires.sched != 0 && | |
832 | (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE && | |
833 | cpu_time_before(timer->it_clock, val, new_expires)) { | |
834 | arm_timer(timer, val); | |
835 | } | |
836 | ||
837 | read_unlock(&tasklist_lock); | |
838 | ||
839 | /* | |
840 | * Install the new reload setting, and | |
841 | * set up the signal and overrun bookkeeping. | |
842 | */ | |
843 | timer->it.cpu.incr = timespec_to_sample(timer->it_clock, | |
844 | &new->it_interval); | |
845 | ||
846 | /* | |
847 | * This acts as a modification timestamp for the timer, | |
848 | * so any automatic reload attempt will punt on seeing | |
849 | * that we have reset the timer manually. | |
850 | */ | |
851 | timer->it_requeue_pending = (timer->it_requeue_pending + 2) & | |
852 | ~REQUEUE_PENDING; | |
853 | timer->it_overrun_last = 0; | |
854 | timer->it_overrun = -1; | |
855 | ||
856 | if (new_expires.sched != 0 && | |
857 | (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE && | |
858 | !cpu_time_before(timer->it_clock, val, new_expires)) { | |
859 | /* | |
860 | * The designated time already passed, so we notify | |
861 | * immediately, even if the thread never runs to | |
862 | * accumulate more time on this clock. | |
863 | */ | |
864 | cpu_timer_fire(timer); | |
865 | } | |
866 | ||
867 | ret = 0; | |
868 | out: | |
869 | if (old) { | |
870 | sample_to_timespec(timer->it_clock, | |
871 | timer->it.cpu.incr, &old->it_interval); | |
872 | } | |
873 | return ret; | |
874 | } | |
875 | ||
876 | void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) | |
877 | { | |
878 | union cpu_time_count now; | |
879 | struct task_struct *p = timer->it.cpu.task; | |
880 | int clear_dead; | |
881 | ||
882 | /* | |
883 | * Easy part: convert the reload time. | |
884 | */ | |
885 | sample_to_timespec(timer->it_clock, | |
886 | timer->it.cpu.incr, &itp->it_interval); | |
887 | ||
888 | if (timer->it.cpu.expires.sched == 0) { /* Timer not armed at all. */ | |
889 | itp->it_value.tv_sec = itp->it_value.tv_nsec = 0; | |
890 | return; | |
891 | } | |
892 | ||
893 | if (unlikely(p == NULL)) { | |
894 | /* | |
895 | * This task already died and the timer will never fire. | |
896 | * In this case, expires is actually the dead value. | |
897 | */ | |
898 | dead: | |
899 | sample_to_timespec(timer->it_clock, timer->it.cpu.expires, | |
900 | &itp->it_value); | |
901 | return; | |
902 | } | |
903 | ||
904 | /* | |
905 | * Sample the clock to take the difference with the expiry time. | |
906 | */ | |
907 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
908 | cpu_clock_sample(timer->it_clock, p, &now); | |
909 | clear_dead = p->exit_state; | |
910 | } else { | |
911 | read_lock(&tasklist_lock); | |
912 | if (unlikely(p->signal == NULL)) { | |
913 | /* | |
914 | * The process has been reaped. | |
915 | * We can't even collect a sample any more. | |
916 | * Call the timer disarmed, nothing else to do. | |
917 | */ | |
918 | put_task_struct(p); | |
919 | timer->it.cpu.task = NULL; | |
920 | timer->it.cpu.expires.sched = 0; | |
921 | read_unlock(&tasklist_lock); | |
922 | goto dead; | |
923 | } else { | |
3997ad31 | 924 | cpu_timer_sample_group(timer->it_clock, p, &now); |
1da177e4 LT |
925 | clear_dead = (unlikely(p->exit_state) && |
926 | thread_group_empty(p)); | |
927 | } | |
928 | read_unlock(&tasklist_lock); | |
929 | } | |
930 | ||
931 | if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) { | |
932 | if (timer->it.cpu.incr.sched == 0 && | |
933 | cpu_time_before(timer->it_clock, | |
934 | timer->it.cpu.expires, now)) { | |
935 | /* | |
936 | * Do-nothing timer expired and has no reload, | |
937 | * so it's as if it was never set. | |
938 | */ | |
939 | timer->it.cpu.expires.sched = 0; | |
940 | itp->it_value.tv_sec = itp->it_value.tv_nsec = 0; | |
941 | return; | |
942 | } | |
943 | /* | |
944 | * Account for any expirations and reloads that should | |
945 | * have happened. | |
946 | */ | |
947 | bump_cpu_timer(timer, now); | |
948 | } | |
949 | ||
950 | if (unlikely(clear_dead)) { | |
951 | /* | |
952 | * We've noticed that the thread is dead, but | |
953 | * not yet reaped. Take this opportunity to | |
954 | * drop our task ref. | |
955 | */ | |
956 | clear_dead_task(timer, now); | |
957 | goto dead; | |
958 | } | |
959 | ||
960 | if (cpu_time_before(timer->it_clock, now, timer->it.cpu.expires)) { | |
961 | sample_to_timespec(timer->it_clock, | |
962 | cpu_time_sub(timer->it_clock, | |
963 | timer->it.cpu.expires, now), | |
964 | &itp->it_value); | |
965 | } else { | |
966 | /* | |
967 | * The timer should have expired already, but the firing | |
968 | * hasn't taken place yet. Say it's just about to expire. | |
969 | */ | |
970 | itp->it_value.tv_nsec = 1; | |
971 | itp->it_value.tv_sec = 0; | |
972 | } | |
973 | } | |
974 | ||
975 | /* | |
976 | * Check for any per-thread CPU timers that have fired and move them off | |
977 | * the tsk->cpu_timers[N] list onto the firing list. Here we update the | |
978 | * tsk->it_*_expires values to reflect the remaining thread CPU timers. | |
979 | */ | |
980 | static void check_thread_timers(struct task_struct *tsk, | |
981 | struct list_head *firing) | |
982 | { | |
e80eda94 | 983 | int maxfire; |
1da177e4 | 984 | struct list_head *timers = tsk->cpu_timers; |
78f2c7db | 985 | struct signal_struct *const sig = tsk->signal; |
1da177e4 | 986 | |
e80eda94 | 987 | maxfire = 20; |
f06febc9 | 988 | tsk->cputime_expires.prof_exp = cputime_zero; |
1da177e4 | 989 | while (!list_empty(timers)) { |
b5e61818 | 990 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
991 | struct cpu_timer_list, |
992 | entry); | |
e80eda94 | 993 | if (!--maxfire || cputime_lt(prof_ticks(tsk), t->expires.cpu)) { |
f06febc9 | 994 | tsk->cputime_expires.prof_exp = t->expires.cpu; |
1da177e4 LT |
995 | break; |
996 | } | |
997 | t->firing = 1; | |
998 | list_move_tail(&t->entry, firing); | |
999 | } | |
1000 | ||
1001 | ++timers; | |
e80eda94 | 1002 | maxfire = 20; |
f06febc9 | 1003 | tsk->cputime_expires.virt_exp = cputime_zero; |
1da177e4 | 1004 | while (!list_empty(timers)) { |
b5e61818 | 1005 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
1006 | struct cpu_timer_list, |
1007 | entry); | |
e80eda94 | 1008 | if (!--maxfire || cputime_lt(virt_ticks(tsk), t->expires.cpu)) { |
f06febc9 | 1009 | tsk->cputime_expires.virt_exp = t->expires.cpu; |
1da177e4 LT |
1010 | break; |
1011 | } | |
1012 | t->firing = 1; | |
1013 | list_move_tail(&t->entry, firing); | |
1014 | } | |
1015 | ||
1016 | ++timers; | |
e80eda94 | 1017 | maxfire = 20; |
f06febc9 | 1018 | tsk->cputime_expires.sched_exp = 0; |
1da177e4 | 1019 | while (!list_empty(timers)) { |
b5e61818 | 1020 | struct cpu_timer_list *t = list_first_entry(timers, |
1da177e4 LT |
1021 | struct cpu_timer_list, |
1022 | entry); | |
41b86e9c | 1023 | if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) { |
f06febc9 | 1024 | tsk->cputime_expires.sched_exp = t->expires.sched; |
1da177e4 LT |
1025 | break; |
1026 | } | |
1027 | t->firing = 1; | |
1028 | list_move_tail(&t->entry, firing); | |
1029 | } | |
78f2c7db PZ |
1030 | |
1031 | /* | |
1032 | * Check for the special case thread timers. | |
1033 | */ | |
1034 | if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) { | |
1035 | unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max; | |
1036 | unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur; | |
1037 | ||
5a52dd50 PZ |
1038 | if (hard != RLIM_INFINITY && |
1039 | tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { | |
78f2c7db PZ |
1040 | /* |
1041 | * At the hard limit, we just die. | |
1042 | * No need to calculate anything else now. | |
1043 | */ | |
1044 | __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); | |
1045 | return; | |
1046 | } | |
1047 | if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) { | |
1048 | /* | |
1049 | * At the soft limit, send a SIGXCPU every second. | |
1050 | */ | |
1051 | if (sig->rlim[RLIMIT_RTTIME].rlim_cur | |
1052 | < sig->rlim[RLIMIT_RTTIME].rlim_max) { | |
1053 | sig->rlim[RLIMIT_RTTIME].rlim_cur += | |
1054 | USEC_PER_SEC; | |
1055 | } | |
81d50bb2 HS |
1056 | printk(KERN_INFO |
1057 | "RT Watchdog Timeout: %s[%d]\n", | |
1058 | tsk->comm, task_pid_nr(tsk)); | |
78f2c7db PZ |
1059 | __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); |
1060 | } | |
1061 | } | |
1da177e4 LT |
1062 | } |
1063 | ||
3fccfd67 PZ |
1064 | static void stop_process_timers(struct task_struct *tsk) |
1065 | { | |
1066 | struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; | |
1067 | unsigned long flags; | |
1068 | ||
1069 | if (!cputimer->running) | |
1070 | return; | |
1071 | ||
1072 | spin_lock_irqsave(&cputimer->lock, flags); | |
1073 | cputimer->running = 0; | |
1074 | spin_unlock_irqrestore(&cputimer->lock, flags); | |
1075 | } | |
1076 | ||
8356b5f9 SG |
1077 | static u32 onecputick; |
1078 | ||
42c4ab41 SG |
1079 | static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it, |
1080 | cputime_t *expires, cputime_t cur_time, int signo) | |
1081 | { | |
1082 | if (cputime_eq(it->expires, cputime_zero)) | |
1083 | return; | |
1084 | ||
1085 | if (cputime_ge(cur_time, it->expires)) { | |
8356b5f9 SG |
1086 | if (!cputime_eq(it->incr, cputime_zero)) { |
1087 | it->expires = cputime_add(it->expires, it->incr); | |
1088 | it->error += it->incr_error; | |
1089 | if (it->error >= onecputick) { | |
1090 | it->expires = cputime_sub(it->expires, | |
a42548a1 | 1091 | cputime_one_jiffy); |
8356b5f9 SG |
1092 | it->error -= onecputick; |
1093 | } | |
3f0a525e | 1094 | } else { |
8356b5f9 | 1095 | it->expires = cputime_zero; |
3f0a525e | 1096 | } |
42c4ab41 | 1097 | |
3f0a525e XG |
1098 | trace_itimer_expire(signo == SIGPROF ? |
1099 | ITIMER_PROF : ITIMER_VIRTUAL, | |
1100 | tsk->signal->leader_pid, cur_time); | |
42c4ab41 SG |
1101 | __group_send_sig_info(signo, SEND_SIG_PRIV, tsk); |
1102 | } | |
1103 | ||
1104 | if (!cputime_eq(it->expires, cputime_zero) && | |
1105 | (cputime_eq(*expires, cputime_zero) || | |
1106 | cputime_lt(it->expires, *expires))) { | |
1107 | *expires = it->expires; | |
1108 | } | |
1109 | } | |
1110 | ||
1da177e4 LT |
1111 | /* |
1112 | * Check for any per-thread CPU timers that have fired and move them | |
1113 | * off the tsk->*_timers list onto the firing list. Per-thread timers | |
1114 | * have already been taken off. | |
1115 | */ | |
1116 | static void check_process_timers(struct task_struct *tsk, | |
1117 | struct list_head *firing) | |
1118 | { | |
e80eda94 | 1119 | int maxfire; |
1da177e4 | 1120 | struct signal_struct *const sig = tsk->signal; |
f06febc9 | 1121 | cputime_t utime, ptime, virt_expires, prof_expires; |
41b86e9c | 1122 | unsigned long long sum_sched_runtime, sched_expires; |
1da177e4 | 1123 | struct list_head *timers = sig->cpu_timers; |
f06febc9 | 1124 | struct task_cputime cputime; |
1da177e4 LT |
1125 | |
1126 | /* | |
1127 | * Don't sample the current process CPU clocks if there are no timers. | |
1128 | */ | |
1129 | if (list_empty(&timers[CPUCLOCK_PROF]) && | |
42c4ab41 | 1130 | cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) && |
1da177e4 LT |
1131 | sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY && |
1132 | list_empty(&timers[CPUCLOCK_VIRT]) && | |
42c4ab41 | 1133 | cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) && |
4cd4c1b4 PZ |
1134 | list_empty(&timers[CPUCLOCK_SCHED])) { |
1135 | stop_process_timers(tsk); | |
1da177e4 | 1136 | return; |
4cd4c1b4 | 1137 | } |
1da177e4 LT |
1138 | |
1139 | /* | |
1140 | * Collect the current process totals. | |
1141 | */ | |
4cd4c1b4 | 1142 | thread_group_cputimer(tsk, &cputime); |
f06febc9 FM |
1143 | utime = cputime.utime; |
1144 | ptime = cputime_add(utime, cputime.stime); | |
1145 | sum_sched_runtime = cputime.sum_exec_runtime; | |
e80eda94 | 1146 | maxfire = 20; |
1da177e4 LT |
1147 | prof_expires = cputime_zero; |
1148 | while (!list_empty(timers)) { | |
ee7dd205 | 1149 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1150 | struct cpu_timer_list, |
1151 | entry); | |
ee7dd205 WC |
1152 | if (!--maxfire || cputime_lt(ptime, tl->expires.cpu)) { |
1153 | prof_expires = tl->expires.cpu; | |
1da177e4 LT |
1154 | break; |
1155 | } | |
ee7dd205 WC |
1156 | tl->firing = 1; |
1157 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1158 | } |
1159 | ||
1160 | ++timers; | |
e80eda94 | 1161 | maxfire = 20; |
1da177e4 LT |
1162 | virt_expires = cputime_zero; |
1163 | while (!list_empty(timers)) { | |
ee7dd205 | 1164 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1165 | struct cpu_timer_list, |
1166 | entry); | |
ee7dd205 WC |
1167 | if (!--maxfire || cputime_lt(utime, tl->expires.cpu)) { |
1168 | virt_expires = tl->expires.cpu; | |
1da177e4 LT |
1169 | break; |
1170 | } | |
ee7dd205 WC |
1171 | tl->firing = 1; |
1172 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1173 | } |
1174 | ||
1175 | ++timers; | |
e80eda94 | 1176 | maxfire = 20; |
1da177e4 LT |
1177 | sched_expires = 0; |
1178 | while (!list_empty(timers)) { | |
ee7dd205 | 1179 | struct cpu_timer_list *tl = list_first_entry(timers, |
1da177e4 LT |
1180 | struct cpu_timer_list, |
1181 | entry); | |
ee7dd205 WC |
1182 | if (!--maxfire || sum_sched_runtime < tl->expires.sched) { |
1183 | sched_expires = tl->expires.sched; | |
1da177e4 LT |
1184 | break; |
1185 | } | |
ee7dd205 WC |
1186 | tl->firing = 1; |
1187 | list_move_tail(&tl->entry, firing); | |
1da177e4 LT |
1188 | } |
1189 | ||
1190 | /* | |
1191 | * Check for the special case process timers. | |
1192 | */ | |
42c4ab41 SG |
1193 | check_cpu_itimer(tsk, &sig->it[CPUCLOCK_PROF], &prof_expires, ptime, |
1194 | SIGPROF); | |
1195 | check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime, | |
1196 | SIGVTALRM); | |
1197 | ||
1da177e4 LT |
1198 | if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { |
1199 | unsigned long psecs = cputime_to_secs(ptime); | |
1200 | cputime_t x; | |
1201 | if (psecs >= sig->rlim[RLIMIT_CPU].rlim_max) { | |
1202 | /* | |
1203 | * At the hard limit, we just die. | |
1204 | * No need to calculate anything else now. | |
1205 | */ | |
1206 | __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); | |
1207 | return; | |
1208 | } | |
1209 | if (psecs >= sig->rlim[RLIMIT_CPU].rlim_cur) { | |
1210 | /* | |
1211 | * At the soft limit, send a SIGXCPU every second. | |
1212 | */ | |
1213 | __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); | |
1214 | if (sig->rlim[RLIMIT_CPU].rlim_cur | |
1215 | < sig->rlim[RLIMIT_CPU].rlim_max) { | |
1216 | sig->rlim[RLIMIT_CPU].rlim_cur++; | |
1217 | } | |
1218 | } | |
1219 | x = secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur); | |
1220 | if (cputime_eq(prof_expires, cputime_zero) || | |
1221 | cputime_lt(x, prof_expires)) { | |
1222 | prof_expires = x; | |
1223 | } | |
1224 | } | |
1225 | ||
f06febc9 FM |
1226 | if (!cputime_eq(prof_expires, cputime_zero) && |
1227 | (cputime_eq(sig->cputime_expires.prof_exp, cputime_zero) || | |
1228 | cputime_gt(sig->cputime_expires.prof_exp, prof_expires))) | |
1229 | sig->cputime_expires.prof_exp = prof_expires; | |
1230 | if (!cputime_eq(virt_expires, cputime_zero) && | |
1231 | (cputime_eq(sig->cputime_expires.virt_exp, cputime_zero) || | |
1232 | cputime_gt(sig->cputime_expires.virt_exp, virt_expires))) | |
1233 | sig->cputime_expires.virt_exp = virt_expires; | |
1234 | if (sched_expires != 0 && | |
1235 | (sig->cputime_expires.sched_exp == 0 || | |
1236 | sig->cputime_expires.sched_exp > sched_expires)) | |
1237 | sig->cputime_expires.sched_exp = sched_expires; | |
1da177e4 LT |
1238 | } |
1239 | ||
1240 | /* | |
1241 | * This is called from the signal code (via do_schedule_next_timer) | |
1242 | * when the last timer signal was delivered and we have to reload the timer. | |
1243 | */ | |
1244 | void posix_cpu_timer_schedule(struct k_itimer *timer) | |
1245 | { | |
1246 | struct task_struct *p = timer->it.cpu.task; | |
1247 | union cpu_time_count now; | |
1248 | ||
1249 | if (unlikely(p == NULL)) | |
1250 | /* | |
1251 | * The task was cleaned up already, no future firings. | |
1252 | */ | |
708f430d | 1253 | goto out; |
1da177e4 LT |
1254 | |
1255 | /* | |
1256 | * Fetch the current sample and update the timer's expiry time. | |
1257 | */ | |
1258 | if (CPUCLOCK_PERTHREAD(timer->it_clock)) { | |
1259 | cpu_clock_sample(timer->it_clock, p, &now); | |
1260 | bump_cpu_timer(timer, now); | |
1261 | if (unlikely(p->exit_state)) { | |
1262 | clear_dead_task(timer, now); | |
708f430d | 1263 | goto out; |
1da177e4 LT |
1264 | } |
1265 | read_lock(&tasklist_lock); /* arm_timer needs it. */ | |
1266 | } else { | |
1267 | read_lock(&tasklist_lock); | |
1268 | if (unlikely(p->signal == NULL)) { | |
1269 | /* | |
1270 | * The process has been reaped. | |
1271 | * We can't even collect a sample any more. | |
1272 | */ | |
1273 | put_task_struct(p); | |
1274 | timer->it.cpu.task = p = NULL; | |
1275 | timer->it.cpu.expires.sched = 0; | |
708f430d | 1276 | goto out_unlock; |
1da177e4 LT |
1277 | } else if (unlikely(p->exit_state) && thread_group_empty(p)) { |
1278 | /* | |
1279 | * We've noticed that the thread is dead, but | |
1280 | * not yet reaped. Take this opportunity to | |
1281 | * drop our task ref. | |
1282 | */ | |
1283 | clear_dead_task(timer, now); | |
708f430d | 1284 | goto out_unlock; |
1da177e4 | 1285 | } |
3997ad31 | 1286 | cpu_timer_sample_group(timer->it_clock, p, &now); |
1da177e4 LT |
1287 | bump_cpu_timer(timer, now); |
1288 | /* Leave the tasklist_lock locked for the call below. */ | |
1289 | } | |
1290 | ||
1291 | /* | |
1292 | * Now re-arm for the new expiry time. | |
1293 | */ | |
1294 | arm_timer(timer, now); | |
1295 | ||
708f430d | 1296 | out_unlock: |
1da177e4 | 1297 | read_unlock(&tasklist_lock); |
708f430d RM |
1298 | |
1299 | out: | |
1300 | timer->it_overrun_last = timer->it_overrun; | |
1301 | timer->it_overrun = -1; | |
1302 | ++timer->it_requeue_pending; | |
1da177e4 LT |
1303 | } |
1304 | ||
f06febc9 FM |
1305 | /** |
1306 | * task_cputime_zero - Check a task_cputime struct for all zero fields. | |
1307 | * | |
1308 | * @cputime: The struct to compare. | |
1309 | * | |
1310 | * Checks @cputime to see if all fields are zero. Returns true if all fields | |
1311 | * are zero, false if any field is nonzero. | |
1312 | */ | |
1313 | static inline int task_cputime_zero(const struct task_cputime *cputime) | |
1314 | { | |
1315 | if (cputime_eq(cputime->utime, cputime_zero) && | |
1316 | cputime_eq(cputime->stime, cputime_zero) && | |
1317 | cputime->sum_exec_runtime == 0) | |
1318 | return 1; | |
1319 | return 0; | |
1320 | } | |
1321 | ||
1322 | /** | |
1323 | * task_cputime_expired - Compare two task_cputime entities. | |
1324 | * | |
1325 | * @sample: The task_cputime structure to be checked for expiration. | |
1326 | * @expires: Expiration times, against which @sample will be checked. | |
1327 | * | |
1328 | * Checks @sample against @expires to see if any field of @sample has expired. | |
1329 | * Returns true if any field of the former is greater than the corresponding | |
1330 | * field of the latter if the latter field is set. Otherwise returns false. | |
1331 | */ | |
1332 | static inline int task_cputime_expired(const struct task_cputime *sample, | |
1333 | const struct task_cputime *expires) | |
1334 | { | |
1335 | if (!cputime_eq(expires->utime, cputime_zero) && | |
1336 | cputime_ge(sample->utime, expires->utime)) | |
1337 | return 1; | |
1338 | if (!cputime_eq(expires->stime, cputime_zero) && | |
1339 | cputime_ge(cputime_add(sample->utime, sample->stime), | |
1340 | expires->stime)) | |
1341 | return 1; | |
1342 | if (expires->sum_exec_runtime != 0 && | |
1343 | sample->sum_exec_runtime >= expires->sum_exec_runtime) | |
1344 | return 1; | |
1345 | return 0; | |
1346 | } | |
1347 | ||
1348 | /** | |
1349 | * fastpath_timer_check - POSIX CPU timers fast path. | |
1350 | * | |
1351 | * @tsk: The task (thread) being checked. | |
f06febc9 | 1352 | * |
bb34d92f FM |
1353 | * Check the task and thread group timers. If both are zero (there are no |
1354 | * timers set) return false. Otherwise snapshot the task and thread group | |
1355 | * timers and compare them with the corresponding expiration times. Return | |
1356 | * true if a timer has expired, else return false. | |
f06febc9 | 1357 | */ |
bb34d92f | 1358 | static inline int fastpath_timer_check(struct task_struct *tsk) |
f06febc9 | 1359 | { |
ad133ba3 | 1360 | struct signal_struct *sig; |
bb34d92f | 1361 | |
ad133ba3 ON |
1362 | /* tsk == current, ensure it is safe to use ->signal/sighand */ |
1363 | if (unlikely(tsk->exit_state)) | |
f06febc9 | 1364 | return 0; |
bb34d92f FM |
1365 | |
1366 | if (!task_cputime_zero(&tsk->cputime_expires)) { | |
1367 | struct task_cputime task_sample = { | |
1368 | .utime = tsk->utime, | |
1369 | .stime = tsk->stime, | |
1370 | .sum_exec_runtime = tsk->se.sum_exec_runtime | |
1371 | }; | |
1372 | ||
1373 | if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) | |
1374 | return 1; | |
1375 | } | |
ad133ba3 ON |
1376 | |
1377 | sig = tsk->signal; | |
bb34d92f FM |
1378 | if (!task_cputime_zero(&sig->cputime_expires)) { |
1379 | struct task_cputime group_sample; | |
1380 | ||
4cd4c1b4 | 1381 | thread_group_cputimer(tsk, &group_sample); |
bb34d92f FM |
1382 | if (task_cputime_expired(&group_sample, &sig->cputime_expires)) |
1383 | return 1; | |
1384 | } | |
37bebc70 ON |
1385 | |
1386 | return sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY; | |
f06febc9 FM |
1387 | } |
1388 | ||
1da177e4 LT |
1389 | /* |
1390 | * This is called from the timer interrupt handler. The irq handler has | |
1391 | * already updated our counts. We need to check if any timers fire now. | |
1392 | * Interrupts are disabled. | |
1393 | */ | |
1394 | void run_posix_cpu_timers(struct task_struct *tsk) | |
1395 | { | |
1396 | LIST_HEAD(firing); | |
1397 | struct k_itimer *timer, *next; | |
1398 | ||
1399 | BUG_ON(!irqs_disabled()); | |
1400 | ||
1da177e4 | 1401 | /* |
f06febc9 | 1402 | * The fast path checks that there are no expired thread or thread |
bb34d92f | 1403 | * group timers. If that's so, just return. |
1da177e4 | 1404 | */ |
bb34d92f | 1405 | if (!fastpath_timer_check(tsk)) |
f06febc9 | 1406 | return; |
5ce73a4a | 1407 | |
bb34d92f FM |
1408 | spin_lock(&tsk->sighand->siglock); |
1409 | /* | |
1410 | * Here we take off tsk->signal->cpu_timers[N] and | |
1411 | * tsk->cpu_timers[N] all the timers that are firing, and | |
1412 | * put them on the firing list. | |
1413 | */ | |
1414 | check_thread_timers(tsk, &firing); | |
1415 | check_process_timers(tsk, &firing); | |
1da177e4 | 1416 | |
bb34d92f FM |
1417 | /* |
1418 | * We must release these locks before taking any timer's lock. | |
1419 | * There is a potential race with timer deletion here, as the | |
1420 | * siglock now protects our private firing list. We have set | |
1421 | * the firing flag in each timer, so that a deletion attempt | |
1422 | * that gets the timer lock before we do will give it up and | |
1423 | * spin until we've taken care of that timer below. | |
1424 | */ | |
1425 | spin_unlock(&tsk->sighand->siglock); | |
1da177e4 LT |
1426 | |
1427 | /* | |
1428 | * Now that all the timers on our list have the firing flag, | |
1429 | * noone will touch their list entries but us. We'll take | |
1430 | * each timer's lock before clearing its firing flag, so no | |
1431 | * timer call will interfere. | |
1432 | */ | |
1433 | list_for_each_entry_safe(timer, next, &firing, it.cpu.entry) { | |
6e85c5ba HS |
1434 | int cpu_firing; |
1435 | ||
1da177e4 LT |
1436 | spin_lock(&timer->it_lock); |
1437 | list_del_init(&timer->it.cpu.entry); | |
6e85c5ba | 1438 | cpu_firing = timer->it.cpu.firing; |
1da177e4 LT |
1439 | timer->it.cpu.firing = 0; |
1440 | /* | |
1441 | * The firing flag is -1 if we collided with a reset | |
1442 | * of the timer, which already reported this | |
1443 | * almost-firing as an overrun. So don't generate an event. | |
1444 | */ | |
6e85c5ba | 1445 | if (likely(cpu_firing >= 0)) |
1da177e4 | 1446 | cpu_timer_fire(timer); |
1da177e4 LT |
1447 | spin_unlock(&timer->it_lock); |
1448 | } | |
1449 | } | |
1450 | ||
1451 | /* | |
1452 | * Set one of the process-wide special case CPU timers. | |
f06febc9 FM |
1453 | * The tsk->sighand->siglock must be held by the caller. |
1454 | * The *newval argument is relative and we update it to be absolute, *oldval | |
1455 | * is absolute and we update it to be relative. | |
1da177e4 LT |
1456 | */ |
1457 | void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, | |
1458 | cputime_t *newval, cputime_t *oldval) | |
1459 | { | |
1460 | union cpu_time_count now; | |
1461 | struct list_head *head; | |
1462 | ||
1463 | BUG_ON(clock_idx == CPUCLOCK_SCHED); | |
4cd4c1b4 | 1464 | cpu_timer_sample_group(clock_idx, tsk, &now); |
1da177e4 LT |
1465 | |
1466 | if (oldval) { | |
1467 | if (!cputime_eq(*oldval, cputime_zero)) { | |
1468 | if (cputime_le(*oldval, now.cpu)) { | |
1469 | /* Just about to fire. */ | |
a42548a1 | 1470 | *oldval = cputime_one_jiffy; |
1da177e4 LT |
1471 | } else { |
1472 | *oldval = cputime_sub(*oldval, now.cpu); | |
1473 | } | |
1474 | } | |
1475 | ||
1476 | if (cputime_eq(*newval, cputime_zero)) | |
1477 | return; | |
1478 | *newval = cputime_add(*newval, now.cpu); | |
1479 | ||
1480 | /* | |
1481 | * If the RLIMIT_CPU timer will expire before the | |
1482 | * ITIMER_PROF timer, we have nothing else to do. | |
1483 | */ | |
1484 | if (tsk->signal->rlim[RLIMIT_CPU].rlim_cur | |
1485 | < cputime_to_secs(*newval)) | |
1486 | return; | |
1487 | } | |
1488 | ||
1489 | /* | |
1490 | * Check whether there are any process timers already set to fire | |
1491 | * before this one. If so, we don't have anything more to do. | |
1492 | */ | |
1493 | head = &tsk->signal->cpu_timers[clock_idx]; | |
1494 | if (list_empty(head) || | |
b5e61818 | 1495 | cputime_ge(list_first_entry(head, |
1da177e4 LT |
1496 | struct cpu_timer_list, entry)->expires.cpu, |
1497 | *newval)) { | |
f06febc9 FM |
1498 | switch (clock_idx) { |
1499 | case CPUCLOCK_PROF: | |
1500 | tsk->signal->cputime_expires.prof_exp = *newval; | |
1501 | break; | |
1502 | case CPUCLOCK_VIRT: | |
1503 | tsk->signal->cputime_expires.virt_exp = *newval; | |
1504 | break; | |
1505 | } | |
1da177e4 LT |
1506 | } |
1507 | } | |
1508 | ||
e4b76555 TA |
1509 | static int do_cpu_nanosleep(const clockid_t which_clock, int flags, |
1510 | struct timespec *rqtp, struct itimerspec *it) | |
1da177e4 | 1511 | { |
1da177e4 LT |
1512 | struct k_itimer timer; |
1513 | int error; | |
1514 | ||
1da177e4 LT |
1515 | /* |
1516 | * Set up a temporary timer and then wait for it to go off. | |
1517 | */ | |
1518 | memset(&timer, 0, sizeof timer); | |
1519 | spin_lock_init(&timer.it_lock); | |
1520 | timer.it_clock = which_clock; | |
1521 | timer.it_overrun = -1; | |
1522 | error = posix_cpu_timer_create(&timer); | |
1523 | timer.it_process = current; | |
1524 | if (!error) { | |
1da177e4 | 1525 | static struct itimerspec zero_it; |
e4b76555 TA |
1526 | |
1527 | memset(it, 0, sizeof *it); | |
1528 | it->it_value = *rqtp; | |
1da177e4 LT |
1529 | |
1530 | spin_lock_irq(&timer.it_lock); | |
e4b76555 | 1531 | error = posix_cpu_timer_set(&timer, flags, it, NULL); |
1da177e4 LT |
1532 | if (error) { |
1533 | spin_unlock_irq(&timer.it_lock); | |
1534 | return error; | |
1535 | } | |
1536 | ||
1537 | while (!signal_pending(current)) { | |
1538 | if (timer.it.cpu.expires.sched == 0) { | |
1539 | /* | |
1540 | * Our timer fired and was reset. | |
1541 | */ | |
1542 | spin_unlock_irq(&timer.it_lock); | |
1543 | return 0; | |
1544 | } | |
1545 | ||
1546 | /* | |
1547 | * Block until cpu_timer_fire (or a signal) wakes us. | |
1548 | */ | |
1549 | __set_current_state(TASK_INTERRUPTIBLE); | |
1550 | spin_unlock_irq(&timer.it_lock); | |
1551 | schedule(); | |
1552 | spin_lock_irq(&timer.it_lock); | |
1553 | } | |
1554 | ||
1555 | /* | |
1556 | * We were interrupted by a signal. | |
1557 | */ | |
1558 | sample_to_timespec(which_clock, timer.it.cpu.expires, rqtp); | |
e4b76555 | 1559 | posix_cpu_timer_set(&timer, 0, &zero_it, it); |
1da177e4 LT |
1560 | spin_unlock_irq(&timer.it_lock); |
1561 | ||
e4b76555 | 1562 | if ((it->it_value.tv_sec | it->it_value.tv_nsec) == 0) { |
1da177e4 LT |
1563 | /* |
1564 | * It actually did fire already. | |
1565 | */ | |
1566 | return 0; | |
1567 | } | |
1568 | ||
e4b76555 TA |
1569 | error = -ERESTART_RESTARTBLOCK; |
1570 | } | |
1571 | ||
1572 | return error; | |
1573 | } | |
1574 | ||
1575 | int posix_cpu_nsleep(const clockid_t which_clock, int flags, | |
1576 | struct timespec *rqtp, struct timespec __user *rmtp) | |
1577 | { | |
1578 | struct restart_block *restart_block = | |
1579 | ¤t_thread_info()->restart_block; | |
1580 | struct itimerspec it; | |
1581 | int error; | |
1582 | ||
1583 | /* | |
1584 | * Diagnose required errors first. | |
1585 | */ | |
1586 | if (CPUCLOCK_PERTHREAD(which_clock) && | |
1587 | (CPUCLOCK_PID(which_clock) == 0 || | |
1588 | CPUCLOCK_PID(which_clock) == current->pid)) | |
1589 | return -EINVAL; | |
1590 | ||
1591 | error = do_cpu_nanosleep(which_clock, flags, rqtp, &it); | |
1592 | ||
1593 | if (error == -ERESTART_RESTARTBLOCK) { | |
1594 | ||
1595 | if (flags & TIMER_ABSTIME) | |
1596 | return -ERESTARTNOHAND; | |
1da177e4 | 1597 | /* |
e4b76555 TA |
1598 | * Report back to the user the time still remaining. |
1599 | */ | |
1600 | if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) | |
1da177e4 LT |
1601 | return -EFAULT; |
1602 | ||
1711ef38 | 1603 | restart_block->fn = posix_cpu_nsleep_restart; |
1da177e4 | 1604 | restart_block->arg0 = which_clock; |
97735f25 | 1605 | restart_block->arg1 = (unsigned long) rmtp; |
1da177e4 LT |
1606 | restart_block->arg2 = rqtp->tv_sec; |
1607 | restart_block->arg3 = rqtp->tv_nsec; | |
1da177e4 | 1608 | } |
1da177e4 LT |
1609 | return error; |
1610 | } | |
1611 | ||
1711ef38 | 1612 | long posix_cpu_nsleep_restart(struct restart_block *restart_block) |
1da177e4 LT |
1613 | { |
1614 | clockid_t which_clock = restart_block->arg0; | |
97735f25 TG |
1615 | struct timespec __user *rmtp; |
1616 | struct timespec t; | |
e4b76555 TA |
1617 | struct itimerspec it; |
1618 | int error; | |
97735f25 TG |
1619 | |
1620 | rmtp = (struct timespec __user *) restart_block->arg1; | |
1621 | t.tv_sec = restart_block->arg2; | |
1622 | t.tv_nsec = restart_block->arg3; | |
1623 | ||
1da177e4 | 1624 | restart_block->fn = do_no_restart_syscall; |
e4b76555 TA |
1625 | error = do_cpu_nanosleep(which_clock, TIMER_ABSTIME, &t, &it); |
1626 | ||
1627 | if (error == -ERESTART_RESTARTBLOCK) { | |
1628 | /* | |
1629 | * Report back to the user the time still remaining. | |
1630 | */ | |
1631 | if (rmtp != NULL && copy_to_user(rmtp, &it.it_value, sizeof *rmtp)) | |
1632 | return -EFAULT; | |
1633 | ||
1634 | restart_block->fn = posix_cpu_nsleep_restart; | |
1635 | restart_block->arg0 = which_clock; | |
1636 | restart_block->arg1 = (unsigned long) rmtp; | |
1637 | restart_block->arg2 = t.tv_sec; | |
1638 | restart_block->arg3 = t.tv_nsec; | |
1639 | } | |
1640 | return error; | |
1641 | ||
1da177e4 LT |
1642 | } |
1643 | ||
1644 | ||
1645 | #define PROCESS_CLOCK MAKE_PROCESS_CPUCLOCK(0, CPUCLOCK_SCHED) | |
1646 | #define THREAD_CLOCK MAKE_THREAD_CPUCLOCK(0, CPUCLOCK_SCHED) | |
1647 | ||
a924b04d TG |
1648 | static int process_cpu_clock_getres(const clockid_t which_clock, |
1649 | struct timespec *tp) | |
1da177e4 LT |
1650 | { |
1651 | return posix_cpu_clock_getres(PROCESS_CLOCK, tp); | |
1652 | } | |
a924b04d TG |
1653 | static int process_cpu_clock_get(const clockid_t which_clock, |
1654 | struct timespec *tp) | |
1da177e4 LT |
1655 | { |
1656 | return posix_cpu_clock_get(PROCESS_CLOCK, tp); | |
1657 | } | |
1658 | static int process_cpu_timer_create(struct k_itimer *timer) | |
1659 | { | |
1660 | timer->it_clock = PROCESS_CLOCK; | |
1661 | return posix_cpu_timer_create(timer); | |
1662 | } | |
a924b04d | 1663 | static int process_cpu_nsleep(const clockid_t which_clock, int flags, |
97735f25 TG |
1664 | struct timespec *rqtp, |
1665 | struct timespec __user *rmtp) | |
1da177e4 | 1666 | { |
97735f25 | 1667 | return posix_cpu_nsleep(PROCESS_CLOCK, flags, rqtp, rmtp); |
1da177e4 | 1668 | } |
1711ef38 TA |
1669 | static long process_cpu_nsleep_restart(struct restart_block *restart_block) |
1670 | { | |
1671 | return -EINVAL; | |
1672 | } | |
a924b04d TG |
1673 | static int thread_cpu_clock_getres(const clockid_t which_clock, |
1674 | struct timespec *tp) | |
1da177e4 LT |
1675 | { |
1676 | return posix_cpu_clock_getres(THREAD_CLOCK, tp); | |
1677 | } | |
a924b04d TG |
1678 | static int thread_cpu_clock_get(const clockid_t which_clock, |
1679 | struct timespec *tp) | |
1da177e4 LT |
1680 | { |
1681 | return posix_cpu_clock_get(THREAD_CLOCK, tp); | |
1682 | } | |
1683 | static int thread_cpu_timer_create(struct k_itimer *timer) | |
1684 | { | |
1685 | timer->it_clock = THREAD_CLOCK; | |
1686 | return posix_cpu_timer_create(timer); | |
1687 | } | |
a924b04d | 1688 | static int thread_cpu_nsleep(const clockid_t which_clock, int flags, |
97735f25 | 1689 | struct timespec *rqtp, struct timespec __user *rmtp) |
1da177e4 LT |
1690 | { |
1691 | return -EINVAL; | |
1692 | } | |
1711ef38 TA |
1693 | static long thread_cpu_nsleep_restart(struct restart_block *restart_block) |
1694 | { | |
1695 | return -EINVAL; | |
1696 | } | |
1da177e4 LT |
1697 | |
1698 | static __init int init_posix_cpu_timers(void) | |
1699 | { | |
1700 | struct k_clock process = { | |
1701 | .clock_getres = process_cpu_clock_getres, | |
1702 | .clock_get = process_cpu_clock_get, | |
1703 | .clock_set = do_posix_clock_nosettime, | |
1704 | .timer_create = process_cpu_timer_create, | |
1705 | .nsleep = process_cpu_nsleep, | |
1711ef38 | 1706 | .nsleep_restart = process_cpu_nsleep_restart, |
1da177e4 LT |
1707 | }; |
1708 | struct k_clock thread = { | |
1709 | .clock_getres = thread_cpu_clock_getres, | |
1710 | .clock_get = thread_cpu_clock_get, | |
1711 | .clock_set = do_posix_clock_nosettime, | |
1712 | .timer_create = thread_cpu_timer_create, | |
1713 | .nsleep = thread_cpu_nsleep, | |
1711ef38 | 1714 | .nsleep_restart = thread_cpu_nsleep_restart, |
1da177e4 | 1715 | }; |
8356b5f9 | 1716 | struct timespec ts; |
1da177e4 LT |
1717 | |
1718 | register_posix_clock(CLOCK_PROCESS_CPUTIME_ID, &process); | |
1719 | register_posix_clock(CLOCK_THREAD_CPUTIME_ID, &thread); | |
1720 | ||
a42548a1 | 1721 | cputime_to_timespec(cputime_one_jiffy, &ts); |
8356b5f9 SG |
1722 | onecputick = ts.tv_nsec; |
1723 | WARN_ON(ts.tv_sec != 0); | |
1724 | ||
1da177e4 LT |
1725 | return 0; |
1726 | } | |
1727 | __initcall(init_posix_cpu_timers); |