linux-kernel - Re: [PATCH 1/2] ACPI: PCC: replace wait_for

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Date:   Wed, 21 Sep 2022 16:47:37 +0100
From:   Sudeep Holla <sudeep.holla@....com>
To:     Huisong Li <lihuisong@...wei.com>
Cc:     linux-acpi@...r.kernel.org, linux-kernel@...r.kernel.org,
        rafael@...nel.org, rafael.j.wysocki@...el.com,
        wanghuiqiang@...wei.com, huangdaode@...wei.com
Subject: Re: [PATCH 1/2] ACPI: PCC: replace wait_for_completion()

On Tue, Sep 20, 2022 at 05:44:59PM +0800, Huisong Li wrote:
> Currently, the function waiting for completion of mailbox operation is
> 'wait_for_completion()'.  The PCC method will be permanently blocked if
> this mailbox message fails to execute. So this patch replaces it with
> 'wait_for_completion_timeout()'. And set the timeout interval to an
> arbitrary retries on top of nominal to prevent the remote processor is
> slow to respond to PCC commands.
>

Sounds good to me. The only concern(may be not serious) is what happens
if we receive response from the platform after the timeout. I have tested
for that in non ACPI non PCC context. I don't have a setup to trigger that
with ACPI PCC + this patch to test. Other than that, I am fine with this:

Reviewed-by: Sudeep Holla <sudeep.holla@....com>

-- 
Regards,
Sudeep