linux-kernel - [PATCH 1/2] cpufreq: intel_pstate: Avoid redundant initialization of local vars

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Date:   Fri, 15 Feb 2019 13:15:32 +0100
From:   "Rafael J. Wysocki" <rjw@...ysocki.net>
To:     Linux PM <linux-pm@...r.kernel.org>
Cc:     Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        LKML <linux-kernel@...r.kernel.org>,
        Chen Yu <y.c.chen@...el.com>,
        Doug Smythies <dsmythies@...us.net>
Subject: [PATCH 1/2] cpufreq: intel_pstate: Avoid redundant initialization of local vars

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

After commit 1a4fe38add8b ("cpufreq: intel_pstate: Remove max/min
fractions to limit performance") the initial value of the pstate local
variable in intel_pstate_max_within_limits() and the initial value of
the max_pstate local variable in intel_pstate_prepare_request() are
both immediately discarded, so initialize both these variables to
their target values upfront.

No intentional changes of behavior.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---
 drivers/cpufreq/intel_pstate.c |   10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

Index: linux-pm/drivers/cpufreq/intel_pstate.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/intel_pstate.c
+++ linux-pm/drivers/cpufreq/intel_pstate.c
@@ -1473,11 +1473,9 @@ static void intel_pstate_set_min_pstate(
 
 static void intel_pstate_max_within_limits(struct cpudata *cpu)
 {
-	int pstate;
+	int pstate = max(cpu->pstate.min_pstate, cpu->max_perf_ratio);
 
 	update_turbo_state();
-	pstate = intel_pstate_get_base_pstate(cpu);
-	pstate = max(cpu->pstate.min_pstate, cpu->max_perf_ratio);
 	intel_pstate_set_pstate(cpu, pstate);
 }
 
@@ -1715,11 +1713,9 @@ static inline int32_t get_target_pstate(
 
 static int intel_pstate_prepare_request(struct cpudata *cpu, int pstate)
 {
-	int max_pstate = intel_pstate_get_base_pstate(cpu);
-	int min_pstate;
+	int min_pstate = max(cpu->pstate.min_pstate, cpu->min_perf_ratio);
+	int max_pstate = max(min_pstate, cpu->max_perf_ratio);
 
-	min_pstate = max(cpu->pstate.min_pstate, cpu->min_perf_ratio);
-	max_pstate = max(min_pstate, cpu->max_perf_ratio);
 	return clamp_t(int, pstate, min_pstate, max_pstate);
 }