Re: [PATCH V3 9/9] cpufreq: drivers: Free frequency tables after being used

From	"Rafael J. Wysocki" <rafael@kernel.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH V3 9/9] cpufreq: drivers: Free frequency tables after being used
Date	2016-06-07 00:50 +0200
Message-ID	<rHbvj-2D4-1@gated-at.bofh.it> (permalink)
References	<rFXup-3Iu-3@gated-at.bofh.it> <rFXur-3Iu-45@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Fri, Jun 3, 2016 at 3:35 PM, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> The cpufreq core doesn't use these tables anymore after
> cpufreq_table_validate_and_show() has returned.  And so these can be
> freed early.

That doesn't look particularly efficient.

The driver has to allocate memory first and populate it and then the
core needs to allocate more memory again to store the same information
in it, but perhaps in a different order and then the driver can free
the memory allocated before right away.  It looks like there's one
excessive memory allocation here, so maybe the core can simply sort
the frequency table in place and overwrite the invalid entries in the
process?

Thread

[PATCH V3 0/9] cpufreq: Sort policy->freq_table Viresh Kumar <viresh.kumar@linaro.org> - 2016-06-03 15:40 +0200
  [PATCH V3 5/9] cpufreq: ia64: Use 'index' only to index into policy->freq_table Viresh Kumar <viresh.kumar@linaro.org> - 2016-06-03 15:40 +0200
  [PATCH V3 9/9] cpufreq: drivers: Free frequency tables after being used Viresh Kumar <viresh.kumar@linaro.org> - 2016-06-03 15:40 +0200
    Re: [PATCH V3 9/9] cpufreq: drivers: Free frequency tables after  being used "Rafael J. Wysocki" <rafael@kernel.org> - 2016-06-07 00:50 +0200
  Re: [PATCH V3 0/9] cpufreq: Sort policy->freq_table "Rafael J. Wysocki" <rafael@kernel.org> - 2016-06-06 23:10 +0200
    Re: [PATCH V3 0/9] cpufreq: Sort policy->freq_table Viresh Kumar <viresh.kumar@linaro.org> - 2016-06-07 05:50 +0200

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