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References: <20231124223226.24249-1-frederic@kernel.org> <20231124223226.24249-5-frederic@kernel.org>
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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Tue, 12 Dec 2023 14:09:38 +0100
Message-ID: <CAJZ5v0jBzqa8UVbarJbFDcqyLsMEVYSuCtcxKk6PUSv3TDnUOQ@mail.gmail.com>
Subject: Re: [PATCH 4/7] cpuidle: s/CPUIDLE_FLAG_POLLING/CPUIDLE_FLAG_POLLING_SOFT
To:     Frederic Weisbecker <frederic@kernel.org>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        linux-pm@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>
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On Fri, Nov 24, 2023 at 11:32 PM Frederic Weisbecker
<frederic@kernel.org> wrote:
>
> In order to further distinguish software and hardware TIF_NEED_RESCHED
> polling cpuidle states, rename CPUIDLE_FLAG_POLLING to
> CPUIDLE_FLAG_POLLING_SOFT before introducing CPUIDLE_FLAG_POLLING_HARD
> and tag mwait users with it.

Well, if MWAIT users are the only category that will be tagged with
the new flag, it can be called CPUIDLE_FLAG_POLLING_MWAIT or even
CPUIDLE_FLAG_MWAIT for that matter and the $subject patch won't be
necessary any more AFAICS.

> This will allow cpuidle core to manage TIF_NR_POLLING on behalf of all
> kinds of TIF_NEED_RESCHED polling states while keeping a necessary
> distinction for the governors between software loops polling on
> TIF_NEED_RESCHED and hardware monitored writes to thread flags.

Fair enough, but what about using a different name for the new flag
and leaving the old one as is?