Re: [PATCH] PM: s2idle: Introduce syscore callbacks in s2idle flow

[Rafael J. Wysocki]

On Tue, Sep 1, 2020 at 9:05 AM Claude Yen <claude.yen@xxxxxxxxxxxx> wrote:
>
> This series based on 5.9-rc1
> This patch makes s2idle call existing syscore callbacks. Currently,
> when s2idle is selected as system suspend method, callbacks hooked
> by register_syscore_ops() will not be triggered. This may induce
> unexpected results.

They are not executed by design.

> For example, sched_clock_suspend() was added to s2idle flow in
> commit 3f2552f7e9c5 ("timers/sched_clock: Prevent generic sched_clock
> wrap caused by tick_freeze()") to fix clock wrap problem. However,
> sched_clock_suspend() is originally registered in syscore callback.

I'm not sure why this matters here.

> With this patch, if another syscore callback is needed in s2idle,
> additional migration effort could be saved.

s2idle cannot execute syscore callbacks, because it doesn' take
non-boot CPUs offline and it won't do that.

Thanks!