| Date | Tue, 27 Jun 2023 12:51:20 +0200 | From | Frederic Weisbecker <> | Subject | Re: [patch 12/45] posix-cpu-timers: Simplify posix_cpu_timer_set() |
| |
On Tue, Jun 06, 2023 at 04:37:37PM +0200, Thomas Gleixner wrote: > Avoid the late sighand lock/unlock dance when a timer is not armed to > enforce reevaluation of the timer base so that the process wide CPU timer > sampling can be disabled. > > Do it right at the point where the arming decision is made which already > has sighand locked. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > --- > kernel/time/posix-cpu-timers.c | 38 +++++++++++++------------------------- > 1 file changed, 13 insertions(+), 25 deletions(-) > > --- a/kernel/time/posix-cpu-timers.c > +++ b/kernel/time/posix-cpu-timers.c > @@ -720,10 +720,14 @@ static int posix_cpu_timer_set(struct k_ > /* > * Arm the timer if it is not disabled, the new expiry value has > * not yet expired and the timer requires signal delivery. > - * SIGEV_NONE timers are never armed. > + * SIGEV_NONE timers are never armed. In case the timer is not > + * armed, enforce the reevaluation of the timer base so that the > + * process wide cputime counter can be disabled eventually. > */ > if (!sigev_none && new_expires && now < new_expires) > arm_timer(timer, p); > + else > + trigger_base_recalc_expires(timer, p);
We don't need a recalc if sigev_none, right?
Thanks.
> > unlock_task_sighand(p, &flags); > /*
|