Messages in this thread | | | Date | Wed, 4 Jun 2014 16:05:14 +0200 | From | Frederic Weisbecker <> | Subject | Re: [Query] Can we use normal timers (kernel/timer.c) while in NO_HZ_FULL mode? |
| |
On Wed, Jun 04, 2014 at 07:14:43PM +0530, Viresh Kumar wrote: > On 4 June 2014 18:53, Frederic Weisbecker <fweisbec@gmail.com> wrote: > > Right, if we enqueue a timer when the tick is stopped, we call wake_up_nohz_cpu(). > > Ahh, I looked at __mod_timer() :) > > BTW, shouldn't we do something similar for mod_timer_pinned() > as well ?
Ah that looks right. In fact we should probably move the wake_up_nohz_cpu() to internal_add_timer().
And that concerns nohz idle as well. If mod_timer() selects a CPU that doesn't appear to be idle in get_nohz_timer_target() but then becomes idle afterward before we lock its timer base, the CPU may well miss the timer.
| |