}
} else {
read_lock(&tasklist_lock);
- if (thread_group_leader(p) && p->signal) {
+ if (thread_group_leader(p) && p->sighand) {
error =
cpu_clock_sample_group(which_clock,
p, &rtn);
if (likely(p != NULL)) {
read_lock(&tasklist_lock);
- if (unlikely(p->signal == NULL)) {
+ if (unlikely(p->sighand == NULL)) {
/*
* We raced with the reaping of the task.
* The deletion should have cleared us off the list.
cputime_gt(expires, new_exp);
}
-static inline int expires_le(cputime_t expires, cputime_t new_exp)
-{
- return !cputime_eq(expires, cputime_zero) &&
- cputime_le(expires, new_exp);
-}
/*
* Insert the timer on the appropriate list before any timers that
* expire later. This must be called with the tasklist_lock held
- * for reading, and interrupts disabled.
+ * for reading, interrupts disabled and p->sighand->siglock taken.
*/
-static void arm_timer(struct k_itimer *timer, union cpu_time_count now)
+static void arm_timer(struct k_itimer *timer)
{
struct task_struct *p = timer->it.cpu.task;
struct list_head *head, *listpos;
+ struct task_cputime *cputime_expires;
struct cpu_timer_list *const nt = &timer->it.cpu;
struct cpu_timer_list *next;
- head = (CPUCLOCK_PERTHREAD(timer->it_clock) ?
- p->cpu_timers : p->signal->cpu_timers);
+ if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
+ head = p->cpu_timers;
+ cputime_expires = &p->cputime_expires;
+ } else {
+ head = p->signal->cpu_timers;
+ cputime_expires = &p->signal->cputime_expires;
+ }
head += CPUCLOCK_WHICH(timer->it_clock);
- BUG_ON(!irqs_disabled());
- spin_lock(&p->sighand->siglock);
-
listpos = head;
- if (CPUCLOCK_WHICH(timer->it_clock) == CPUCLOCK_SCHED) {
- list_for_each_entry(next, head, entry) {
- if (next->expires.sched > nt->expires.sched)
- break;
- listpos = &next->entry;
- }
- } else {
- list_for_each_entry(next, head, entry) {
- if (cputime_gt(next->expires.cpu, nt->expires.cpu))
- break;
- listpos = &next->entry;
- }
+ list_for_each_entry(next, head, entry) {
+ if (cpu_time_before(timer->it_clock, nt->expires, next->expires))
+ break;
+ listpos = &next->entry;
}
list_add(&nt->entry, listpos);
if (listpos == head) {
+ union cpu_time_count *exp = &nt->expires;
+
/*
- * We are the new earliest-expiring timer.
- * If we are a thread timer, there can always
- * be a process timer telling us to stop earlier.
+ * We are the new earliest-expiring POSIX 1.b timer, hence
+ * need to update expiration cache. Take into account that
+ * for process timers we share expiration cache with itimers
+ * and RLIMIT_CPU and for thread timers with RLIMIT_RTTIME.
*/
- if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
- union cpu_time_count *exp = &nt->expires;
-
- switch (CPUCLOCK_WHICH(timer->it_clock)) {
- default:
- BUG();
- case CPUCLOCK_PROF:
- if (expires_gt(p->cputime_expires.prof_exp,
- exp->cpu))
- p->cputime_expires.prof_exp = exp->cpu;
- break;
- case CPUCLOCK_VIRT:
- if (expires_gt(p->cputime_expires.virt_exp,
- exp->cpu))
- p->cputime_expires.virt_exp = exp->cpu;
- break;
- case CPUCLOCK_SCHED:
- if (p->cputime_expires.sched_exp == 0 ||
- p->cputime_expires.sched_exp > exp->sched)
- p->cputime_expires.sched_exp =
- exp->sched;
- break;
- }
- } else {
- struct signal_struct *const sig = p->signal;
- union cpu_time_count *exp = &timer->it.cpu.expires;
-
- /*
- * For a process timer, set the cached expiration time.
- */
- switch (CPUCLOCK_WHICH(timer->it_clock)) {
- default:
- BUG();
- case CPUCLOCK_VIRT:
- if (expires_gt(sig->cputime_expires.virt_exp, exp->cpu))
- sig->cputime_expires.virt_exp = exp->cpu;
- case CPUCLOCK_PROF:
- if (expires_gt(sig->cputime_expires.prof_exp, exp->cpu))
- sig->cputime_expires.prof_exp = exp->cpu;
- break;
- case CPUCLOCK_SCHED:
- sig->cputime_expires.sched_exp = exp->sched;
- break;
- }
+ switch (CPUCLOCK_WHICH(timer->it_clock)) {
+ case CPUCLOCK_PROF:
+ if (expires_gt(cputime_expires->prof_exp, exp->cpu))
+ cputime_expires->prof_exp = exp->cpu;
+ break;
+ case CPUCLOCK_VIRT:
+ if (expires_gt(cputime_expires->virt_exp, exp->cpu))
+ cputime_expires->virt_exp = exp->cpu;
+ break;
+ case CPUCLOCK_SCHED:
+ if (cputime_expires->sched_exp == 0 ||
+ cputime_expires->sched_exp > exp->sched)
+ cputime_expires->sched_exp = exp->sched;
+ break;
}
}
-
- spin_unlock(&p->sighand->siglock);
}
/*
*/
static void cpu_timer_fire(struct k_itimer *timer)
{
- if (unlikely(timer->sigq == NULL)) {
+ if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
+ /*
+ * User don't want any signal.
+ */
+ timer->it.cpu.expires.sched = 0;
+ } else if (unlikely(timer->sigq == NULL)) {
/*
* This a special case for clock_nanosleep,
* not a normal timer from sys_timer_create.
struct itimerspec *new, struct itimerspec *old)
{
struct task_struct *p = timer->it.cpu.task;
- union cpu_time_count old_expires, new_expires, val;
+ union cpu_time_count old_expires, new_expires, old_incr, val;
int ret;
if (unlikely(p == NULL)) {
read_lock(&tasklist_lock);
/*
* We need the tasklist_lock to protect against reaping that
- * clears p->signal. If p has just been reaped, we can no
+ * clears p->sighand. If p has just been reaped, we can no
* longer get any information about it at all.
*/
- if (unlikely(p->signal == NULL)) {
+ if (unlikely(p->sighand == NULL)) {
read_unlock(&tasklist_lock);
put_task_struct(p);
timer->it.cpu.task = NULL;
BUG_ON(!irqs_disabled());
ret = 0;
+ old_incr = timer->it.cpu.incr;
spin_lock(&p->sighand->siglock);
old_expires = timer->it.cpu.expires;
if (unlikely(timer->it.cpu.firing)) {
ret = TIMER_RETRY;
} else
list_del_init(&timer->it.cpu.entry);
- spin_unlock(&p->sighand->siglock);
/*
* We need to sample the current value to convert the new
* disable this firing since we are already reporting
* it as an overrun (thanks to bump_cpu_timer above).
*/
+ spin_unlock(&p->sighand->siglock);
read_unlock(&tasklist_lock);
goto out;
}
*/
timer->it.cpu.expires = new_expires;
if (new_expires.sched != 0 &&
- (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE &&
cpu_time_before(timer->it_clock, val, new_expires)) {
- arm_timer(timer, val);
+ arm_timer(timer);
}
+ spin_unlock(&p->sighand->siglock);
read_unlock(&tasklist_lock);
/*
timer->it_overrun = -1;
if (new_expires.sched != 0 &&
- (timer->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE &&
!cpu_time_before(timer->it_clock, val, new_expires)) {
/*
* The designated time already passed, so we notify
out:
if (old) {
sample_to_timespec(timer->it_clock,
- timer->it.cpu.incr, &old->it_interval);
+ old_incr, &old->it_interval);
}
return ret;
}
clear_dead = p->exit_state;
} else {
read_lock(&tasklist_lock);
- if (unlikely(p->signal == NULL)) {
+ if (unlikely(p->sighand == NULL)) {
/*
* The process has been reaped.
* We can't even collect a sample any more.
read_unlock(&tasklist_lock);
}
- if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
- if (timer->it.cpu.incr.sched == 0 &&
- cpu_time_before(timer->it_clock,
- timer->it.cpu.expires, now)) {
- /*
- * Do-nothing timer expired and has no reload,
- * so it's as if it was never set.
- */
- timer->it.cpu.expires.sched = 0;
- itp->it_value.tv_sec = itp->it_value.tv_nsec = 0;
- return;
- }
- /*
- * Account for any expirations and reloads that should
- * have happened.
- */
- bump_cpu_timer(timer, now);
- }
-
if (unlikely(clear_dead)) {
/*
* We've noticed that the thread is dead, but
}
}
-static void stop_process_timers(struct task_struct *tsk)
+static void stop_process_timers(struct signal_struct *sig)
{
- struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+ struct thread_group_cputimer *cputimer = &sig->cputimer;
unsigned long flags;
- if (!cputimer->running)
- return;
-
spin_lock_irqsave(&cputimer->lock, flags);
cputimer->running = 0;
spin_unlock_irqrestore(&cputimer->lock, flags);
}
}
+/**
+ * task_cputime_zero - Check a task_cputime struct for all zero fields.
+ *
+ * @cputime: The struct to compare.
+ *
+ * Checks @cputime to see if all fields are zero. Returns true if all fields
+ * are zero, false if any field is nonzero.
+ */
+static inline int task_cputime_zero(const struct task_cputime *cputime)
+{
+ if (cputime_eq(cputime->utime, cputime_zero) &&
+ cputime_eq(cputime->stime, cputime_zero) &&
+ cputime->sum_exec_runtime == 0)
+ return 1;
+ return 0;
+}
+
/*
* Check for any per-thread CPU timers that have fired and move them
* off the tsk->*_timers list onto the firing list. Per-thread timers
unsigned long soft;
/*
- * Don't sample the current process CPU clocks if there are no timers.
- */
- if (list_empty(&timers[CPUCLOCK_PROF]) &&
- cputime_eq(sig->it[CPUCLOCK_PROF].expires, cputime_zero) &&
- sig->rlim[RLIMIT_CPU].rlim_cur == RLIM_INFINITY &&
- list_empty(&timers[CPUCLOCK_VIRT]) &&
- cputime_eq(sig->it[CPUCLOCK_VIRT].expires, cputime_zero) &&
- list_empty(&timers[CPUCLOCK_SCHED])) {
- stop_process_timers(tsk);
- return;
- }
-
- /*
* Collect the current process totals.
*/
thread_group_cputimer(tsk, &cputime);
}
}
- if (!cputime_eq(prof_expires, cputime_zero) &&
- (cputime_eq(sig->cputime_expires.prof_exp, cputime_zero) ||
- cputime_gt(sig->cputime_expires.prof_exp, prof_expires)))
- sig->cputime_expires.prof_exp = prof_expires;
- if (!cputime_eq(virt_expires, cputime_zero) &&
- (cputime_eq(sig->cputime_expires.virt_exp, cputime_zero) ||
- cputime_gt(sig->cputime_expires.virt_exp, virt_expires)))
- sig->cputime_expires.virt_exp = virt_expires;
- if (sched_expires != 0 &&
- (sig->cputime_expires.sched_exp == 0 ||
- sig->cputime_expires.sched_exp > sched_expires))
- sig->cputime_expires.sched_exp = sched_expires;
+ sig->cputime_expires.prof_exp = prof_expires;
+ sig->cputime_expires.virt_exp = virt_expires;
+ sig->cputime_expires.sched_exp = sched_expires;
+ if (task_cputime_zero(&sig->cputime_expires))
+ stop_process_timers(sig);
}
/*
goto out;
}
read_lock(&tasklist_lock); /* arm_timer needs it. */
+ spin_lock(&p->sighand->siglock);
} else {
read_lock(&tasklist_lock);
- if (unlikely(p->signal == NULL)) {
+ if (unlikely(p->sighand == NULL)) {
/*
* The process has been reaped.
* We can't even collect a sample any more.
clear_dead_task(timer, now);
goto out_unlock;
}
+ spin_lock(&p->sighand->siglock);
cpu_timer_sample_group(timer->it_clock, p, &now);
bump_cpu_timer(timer, now);
/* Leave the tasklist_lock locked for the call below. */
/*
* Now re-arm for the new expiry time.
*/
- arm_timer(timer, now);
+ BUG_ON(!irqs_disabled());
+ arm_timer(timer);
+ spin_unlock(&p->sighand->siglock);
out_unlock:
read_unlock(&tasklist_lock);
}
/**
- * task_cputime_zero - Check a task_cputime struct for all zero fields.
- *
- * @cputime: The struct to compare.
- *
- * Checks @cputime to see if all fields are zero. Returns true if all fields
- * are zero, false if any field is nonzero.
- */
-static inline int task_cputime_zero(const struct task_cputime *cputime)
-{
- if (cputime_eq(cputime->utime, cputime_zero) &&
- cputime_eq(cputime->stime, cputime_zero) &&
- cputime->sum_exec_runtime == 0)
- return 1;
- return 0;
-}
-
-/**
* task_cputime_expired - Compare two task_cputime entities.
*
* @sample: The task_cputime structure to be checked for expiration.
}
sig = tsk->signal;
- if (!task_cputime_zero(&sig->cputime_expires)) {
+ if (sig->cputimer.running) {
struct task_cputime group_sample;
thread_group_cputimer(tsk, &group_sample);
* put them on the firing list.
*/
check_thread_timers(tsk, &firing);
- check_process_timers(tsk, &firing);
+ /*
+ * If there are any active process wide timers (POSIX 1.b, itimers,
+ * RLIMIT_CPU) cputimer must be running.
+ */
+ if (tsk->signal->cputimer.running)
+ check_process_timers(tsk, &firing);
/*
* We must release these locks before taking any timer's lock.
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff