lkml.org 
[lkml]   [2015]   [Sep]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] arm64: add cpu_idle tracepoints to arch_cpu_idle
Dear Lorenzo,

On Wed, 16 Sep 2015 15:47:38 +0100
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote:

> On Wed, Sep 16, 2015 at 03:23:21PM +0100, Jisheng Zhang wrote:
> > Currently, if cpuidle is disabled or not supported, powertop reports
> > zero wakeups and zero events. This is due to the cpu_idle tracepoints
> > are missing.
> >
> > This patch is to make cpu_idle tracepoints always available even if
> > cpuidle is disabled or not supported.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
>
> Is there a reason why this code cannot be moved to the generic idle loop ?

Do you mean the cpu_idle_loop() in kernel/sched/idle.c? To be honest, I
dunno. Maybe kernel experts can give some hints.

Thanks,
Jisheng

>
> Thanks,
> Lorenzo
>
> > ---
> > arch/arm64/kernel/process.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> > index 223b093..f75b540 100644
> > --- a/arch/arm64/kernel/process.c
> > +++ b/arch/arm64/kernel/process.c
> > @@ -44,6 +44,7 @@
> > #include <linux/hw_breakpoint.h>
> > #include <linux/personality.h>
> > #include <linux/notifier.h>
> > +#include <trace/events/power.h>
> >
> > #include <asm/compat.h>
> > #include <asm/cacheflush.h>
> > @@ -75,8 +76,10 @@ void arch_cpu_idle(void)
> > * This should do all the clock switching and wait for interrupt
> > * tricks
> > */
> > + trace_cpu_idle_rcuidle(1, smp_processor_id());
> > cpu_do_idle();
> > local_irq_enable();
> > + trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
> > }
> >
> > #ifdef CONFIG_HOTPLUG_CPU
> > --
> > 2.5.1
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at http://www.tux.org/lkml/
> >



\
 
 \ /
  Last update: 2015-09-16 17:01    [W:0.077 / U:0.496 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site