Messages in this thread | | | Date | Fri, 16 Aug 2013 18:19:54 +0200 | From | Oleg Nesterov <> | Subject | Re: [PATCH 4/4] nohz: Convert a few places to use local per cpu accesses |
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On 08/16, Peter Zijlstra wrote: > > OK so these patches look ok to me -- didn't read in detail though. > > On Fri, Aug 16, 2013 at 05:42:33PM +0200, Frederic Weisbecker wrote: > > A few functions use remote per CPU access APIs when they > > deal with local values. > > > > Just to the right conversion to improve performance, code > > readability and debug checks. > > > @@ -410,7 +408,7 @@ static void tick_nohz_update_jiffies(ktime_t now) > > > > static void tick_nohz_stop_idle(int cpu, ktime_t now) > > { > > - struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); > > + struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); > > What's there from stopping someone from calling this with cpu != > smp_processor_id() ?
I _guess_ this should not happen, but in this case we should probably remove the "cpu" argument. And smp_processor_id() in tick_nohz_idle_exit().
tick_check_idle/tick_check_nohz doesn't need "int cpu" too, it seems.
Oleg.
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