}
} 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.
/*
* 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)
{
}
head += CPUCLOCK_WHICH(timer->it_clock);
- BUG_ON(!irqs_disabled());
- spin_lock(&p->sighand->siglock);
-
listpos = head;
list_for_each_entry(next, head, entry) {
if (cpu_time_before(timer->it_clock, nt->expires, next->expires))
break;
}
}
-
- spin_unlock(&p->sighand->siglock);
}
/*
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;
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;
}
arm_timer(timer);
}
+ spin_unlock(&p->sighand->siglock);
read_unlock(&tasklist_lock);
/*
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.
}
}
-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.
*/
+ 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