Messages in this thread | | | Date | Mon, 6 Apr 2009 18:48:48 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [v5 PATCH 4/4] timers: logic to move non pinned timers |
| |
Arun,
On Mon, 6 Apr 2009, Arun R Bharadwaj wrote: > +again: > + new_cpu_base = &per_cpu(hrtimer_bases, cpu); > new_base = &new_cpu_base->clock_base[base->index]; > > if (base != new_base) { > @@ -219,6 +230,34 @@ switch_hrtimer_base(struct hrtimer *time > timer->base = NULL; > spin_unlock(&base->cpu_base->lock); > spin_lock(&new_base->cpu_base->lock); > + > + if (cpu == preferred_cpu) { > + /* Calculate clock monotonic expiry time */ > + ktime_t expires = ktime_sub(hrtimer_get_expires(timer), > + new_base->offset); > + > + /* > + * Get the next event on target cpu from the > + * clock events layer. > + * This covers the highres=off nohz=on case as well. > + */ > + ktime_t next = clockevents_get_next_event(cpu); > + > + ktime_t delta = ktime_sub(expires, next); > + > + /* > + * We do not migrate the timer when it is expiring > + * before the next event on the target cpu because > + * we cannot reprogram the target cpu hardware and > + * we would cause it to fire late. > + */ > + if (delta.tv64 < 0) { > + cpu = smp_processor_id(); > + spin_unlock(&new_base->cpu_base->lock); > + spin_lock(&base->cpu_base->lock);
Darn, I knew that I missed something when I looked at this before:
timer->base = base;
Thanks,
tglx
| |