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Message-ID: <28a92577c83276baf355dc8de272a79dc854025a.camel@linux.intel.com>
Subject: Re: [PATCH 2/2] intel_idle: Introduce 'states_off' module parameter
From:   Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reply-To: artem.bityutskiy@linux.intel.com
To:     David Laight <David.Laight@ACULAB.COM>,
        "'Rafael J. Wysocki'" <rjw@rjwysocki.net>,
        Linux PM <linux-pm@vger.kernel.org>
Cc:     Linux ACPI <linux-acpi@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Len Brown <len.brown@intel.com>,
        Zhang Rui <rui.zhang@intel.com>,
        David Box <david.e.box@linux.intel.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Fri, 31 Jan 2020 13:24:24 +0200
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On Fri, 2020-01-31 at 11:07 +0000, David Laight wrote:
> Unless you know exactly which cpu table is being used the
> only constraint a user can request is the latency.

Hi David,

in all my use-cases I always know what is the CPU I am dealing with and
what are the C-states. Simply because in my view they are always CPU-
dependent in terms of what they do and how are they named.

What you say sounds to me like you would want to disable some C-states
without knowing anything (or much) about the CPU you are dealing with
and the C-state names.

If so, could you please share examples of such use-cases?

Thanks!

-- 
Best Regards,
Artem Bityutskiy