linux-kernel - [PATCH] cpufreq: intel_pstate: Simplify intel_pstate_cpu

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Date:   Wed, 25 Mar 2020 16:18:09 +0100
From:   "Rafael J. Wysocki" <rjw@...ysocki.net>
To:     Linux PM <linux-pm@...r.kernel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>
Subject: [PATCH] cpufreq: intel_pstate: Simplify intel_pstate_cpu_init()

From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>

The initial policy value set by intel_pstate_cpu_init() depends on
whether or not CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is set, but
that is not necessary, because the core will set the policy to
"performance" in cpufreq_init_policy() if the default governor is
"performance" anyway.

Accordingly, change intel_pstate_cpu_init() to always set policy
to CPUFREQ_POLICY_POWERSAVE initially to provide a valid fallback
value to cpufreq_init_policy() in case the default cpufreq governor
is neither "powersave" nor "performance".

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---
 drivers/cpufreq/intel_pstate.c |    9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

Index: linux-pm/drivers/cpufreq/intel_pstate.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/intel_pstate.c
+++ linux-pm/drivers/cpufreq/intel_pstate.c
@@ -2247,10 +2247,11 @@ static int intel_pstate_cpu_init(struct
 	if (ret)
 		return ret;

-	if (IS_ENABLED(CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE))
-		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
-	else
-		policy->policy = CPUFREQ_POLICY_POWERSAVE;
+	/*
+	 * Set the policy to powersave to provide a valid fallback value in case
+	 * the default cpufreq governor is neither powersave nor performance.
+	 */
+	policy->policy = CPUFREQ_POLICY_POWERSAVE;

 	return 0;
 }