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| author | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2024-12-02 11:22:11 -0500 |
|---|---|---|
| committer | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2024-12-02 11:22:11 -0500 |
| commit | 8f109f287fdc7b8fc7dcb6b2190c8b17dc22fcda (patch) | |
| tree | 8c59d34866fcb6d121bbb30014ca46a49a818f1b /kernel/time/itimer.c | |
| parent | 54254727837440966c3381ea688df002ff14f269 (diff) | |
| parent | 40384c840ea1944d7c5a392e8975ed088ecf0b37 (diff) | |
Merge drm/drm-next into drm-xe-next
A backmerge to get the PMT preparation work for
merging the BMG PMT support.
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Diffstat (limited to 'kernel/time/itimer.c')
| -rw-r--r-- | kernel/time/itimer.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c index 00629e658ca1..876d389b2e21 100644 --- a/kernel/time/itimer.c +++ b/kernel/time/itimer.c @@ -151,7 +151,27 @@ COMPAT_SYSCALL_DEFINE2(getitimer, int, which, #endif /* - * The timer is automagically restarted, when interval != 0 + * Invoked from dequeue_signal() when SIG_ALRM is delivered. + * + * Restart the ITIMER_REAL timer if it is armed as periodic timer. Doing + * this in the signal delivery path instead of self rearming prevents a DoS + * with small increments in the high reolution timer case and reduces timer + * noise in general. + */ +void posixtimer_rearm_itimer(struct task_struct *tsk) +{ + struct hrtimer *tmr = &tsk->signal->real_timer; + + if (!hrtimer_is_queued(tmr) && tsk->signal->it_real_incr != 0) { + hrtimer_forward(tmr, tmr->base->get_time(), + tsk->signal->it_real_incr); + hrtimer_restart(tmr); + } +} + +/* + * Interval timers are restarted in the signal delivery path. See + * posixtimer_rearm_itimer(). */ enum hrtimer_restart it_real_fn(struct hrtimer *timer) { |