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From:   "Rafael J. Wysocki" <rjw@rjwysocki.net>
To:     Viresh Kumar <viresh.kumar@linaro.org>
Cc:     Len Brown <len.brown@intel.com>, Pavel Machek <pavel@ucw.cz>,
        Kevin Hilman <khilman@kernel.org>,
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        linux-pm@vger.kernel.org,
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        Qais.Yousef@arm.com, mka@chromium.org, juri.lelli@gmail.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH V3 2/5] PM / QOS: Pass request type to dev_pm_qos_read_value()
Date:   Tue, 18 Jun 2019 01:14:15 +0200
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On Monday, June 10, 2019 12:51:33 PM CEST Viresh Kumar wrote:
> In order to use dev_pm_qos_read_value(), and other internal routines to
> it, to read values for different QoS requests, pass request type as a
> parameter to these routines.
> 
> For now, it only supports resume-latency request type.

I don't quite like the structure by which the type arg is passed through the
entire call chain until the switch in dep_pm_qos_raw_read_value().

There is only one direct user of dev_pm_qos_raw_read_value() AFAICS which
is cpuidle. It shouldn't need to suffer the general case overhead, so I would
rename that function to dev_pm_qos_raw_resume_latency() and update cpuidle
accordingly.

Moreover, the callers of __dev_pm_qos_read_value() are interested in the
resume latency value too, so it might make sense to rename this as
__dev_pm_qos_resume_latency(), update its callers and put the switch
into dev_pm_qos_read_value().

Plus the changelog should explain the broader rationale of this change like
for the first patch IMO.