linux-kernel - [Question] About unnecessary policy_has_boost_freq() calls in freq

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Message-ID: <e221cef4-a26c-4f9d-ae5c-7dffa78b5e66@kylinos.cn>
Date: Tue, 23 Sep 2025 16:53:46 +0800
From: Zihuan Zhang <zhangzihuan@...inos.cn>
To: "Rafael J. wysocki" <rafael@...nel.org>,
 Viresh Kumar <viresh.kumar@...aro.org>
Cc: "zhenglifeng (A)" <zhenglifeng1@...wei.com>,
 Linux PM <linux-pm@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [Question] About unnecessary policy_has_boost_freq() calls in
 freq_table.c

Hi all,

While reviewing the cpufreq code, I noticed that in 
cpufreq_table_validate_and_sort() the function policy_has_boost_freq() 
is still being called, even though most cpufreq drivers do not make use 
of the CPUFREQ_BOOST_FREQ flag.

code in cpufreq_table_validate_and_sort():

         /* Driver's may have set this field already */
         if (policy_has_boost_freq(policy))
                 policy->boost_supported = true;

For drivers like acpi-cpufreq that don’t rely on CPUFREQ_BOOST_FREQ 
flag, this extra check looks confusing and possibly unnecessary.

Would it make sense to move this check into cpufreq_boost_set_sw() 
instead, so that the call is only made when boost is actually relevant?

Thanks,
Zihuan Zhang