linux-kernel - [PATCH v3 09/11] cpufreq: amd-pstate: Optimize amd_pstate_update

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Message-ID: <20240905163007.1350840-10-superm1@kernel.org>
Date: Thu,  5 Sep 2024 11:30:05 -0500
From: Mario Limonciello <superm1@...nel.org>
To: "Gautham R . Shenoy" <gautham.shenoy@....com>,
	Perry Yuan <perry.yuan@....com>
Cc: Borislav Petkov <bp@...en8.de>,
	x86@...nel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
	"Rafael J . Wysocki" <rafael@...nel.org>,
	linux-kernel@...r.kernel.org (open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
	linux-acpi@...r.kernel.org (open list:ACPI),
	linux-pm@...r.kernel.org (open list:CPU FREQUENCY SCALING FRAMEWORK),
	Mario Limonciello <mario.limonciello@....com>
Subject: [PATCH v3 09/11] cpufreq: amd-pstate: Optimize amd_pstate_update_limits()

From: Mario Limonciello <mario.limonciello@....com>

Don't take and release the mutex when prefcore isn't present and
avoid initialization of variables that will be initially set
in the function.

Reviewed-by: Gautham R. Shenoy <gautham.shenoy@....com>
Reviewed-by: Perry Yuan <perry.yuan@....com>
Signed-off-by: Mario Limonciello <mario.limonciello@....com>
---
 drivers/cpufreq/amd-pstate.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 3ae41af6f041e..9312d4e40994f 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -797,17 +797,17 @@ static void amd_pstate_update_limits(unsigned int cpu)
 	int ret;
 	bool highest_perf_changed = false;
 
-	mutex_lock(&amd_pstate_driver_lock);
-	if ((!amd_pstate_prefcore) || (!cpudata->hw_prefcore))
-		goto free_cpufreq_put;
+	if (!amd_pstate_prefcore)
+		return;
 
+	mutex_lock(&amd_pstate_driver_lock);
 	ret = amd_get_highest_perf(cpu, &cur_high);
 	if (ret)
 		goto free_cpufreq_put;
 
 	prev_high = READ_ONCE(cpudata->prefcore_ranking);
-	if (prev_high != cur_high) {
-		highest_perf_changed = true;
+	highest_perf_changed = (prev_high != cur_high);
+	if (highest_perf_changed) {
 		WRITE_ONCE(cpudata->prefcore_ranking, cur_high);
 
 		if (cur_high < CPPC_MAX_PERF)
-- 
2.43.0