Re: [RFC PATCH 05/11] drivers/acpi: convert seqno counter_atomic

Rafael J. Wysocki
2020-09-24T15:32:59Z

On Thu, Sep 24, 2020 at 5:08 PM Shuah Khan <skhan@linuxfoundation.org> wrote:
>
> On 9/24/20 5:13 AM, Rafael J. Wysocki wrote:
> > On Wed, Sep 23, 2020 at 3:44 AM Shuah Khan <skhan@linuxfoundation.org> wrote:
> >>
> >> counter_atomic is introduced to be used when a variable is used as
> >> a simple counter and doesn't guard object lifetimes. This clearly
> >> differentiates atomic_t usages that guard object lifetimes.
> >>
> >> counter_atomic variables will wrap around to 0 when it overflows and
> >> should not be used to guard resource lifetimes, device usage and
> >> open counts that control state changes, and pm states.
> >>
> >> seqno is a sequence number counter for logging. This counter gets
> >> incremented. Unsure if there is a chance of this overflowing. It
> >> doesn't look like overflowing causes any problems since it is used
> >> to tag the log messages and nothing more.
> >>
> >> Convert it to use counter_atomic.
> >>
> >> This conversion doesn't change the oveflow wrap around behavior.
>
> I see typo here. Will fix it.
>
> >>
> >> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
> >
> > Both this change and the next patch are fine by me.
> >
>
> Thanks Rafael. Okay to add your Acked-by?

Sure.

Thanks!