Re: [PATCH] ARM: cpuidle: declare cpuidle_ops __read_mostly

From: Arnd Bergmann
Date: Wed Aug 10 2016 - 16:53:47 EST


On Wednesday, August 10, 2016 5:54:03 PM CEST Jisheng Zhang wrote:
> On Wed, 10 Aug 2016 16:49:57 +0800 Jisheng Zhang wrote:
>
> > cpuidle_ops is initialized once by arm_cpuidle_read_ops() during
> > initialization, and thereafter is mostly read in arm_cpuidle_suspend()
> >
> > The fact that it is mostly read and not written to makes it candidates
> > for __read_mostly declarations.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
> > ---
> > arch/arm/kernel/cpuidle.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/kernel/cpuidle.c b/arch/arm/kernel/cpuidle.c
> > index 7dccc96..762e0929 100644
> > --- a/arch/arm/kernel/cpuidle.c
> > +++ b/arch/arm/kernel/cpuidle.c
> > @@ -19,7 +19,7 @@ extern struct of_cpuidle_method __cpuidle_method_of_table[];
> > static const struct of_cpuidle_method __cpuidle_method_of_table_sentinel
> > __used __section(__cpuidle_method_of_table_end);
> >
> > -static struct cpuidle_ops cpuidle_ops[NR_CPUS];
> > +static struct cpuidle_ops cpuidle_ops[NR_CPUS] __read_mostly;
>
>
> oops, I just found that "arm: apply more __ro_after_init" from Kees
> marked cpuidle_ops as __ro_after_init, that also meet my need, so
> let's drop my patch.
>
>

Ok, just saw this reply and that matches up with what I just
wrote as well.

Thanks,

Arnd