linux-kernel - [PATCH 1/2] cpufreq: use strlen() for governor name comparison

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Message-Id: <20250819103940.342774-2-zhangzihuan@kylinos.cn>
Date: Tue, 19 Aug 2025 18:39:39 +0800
From: Zihuan Zhang <zhangzihuan@...inos.cn>
To: "rafael J . wysocki" <rafael@...nel.org>,
	Viresh Kumar <viresh.kumar@...aro.org>
Cc: zhenglifeng <zhenglifeng1@...wei.com>,
	linux-pm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Zihuan Zhang <zhangzihuan@...inos.cn>
Subject: [PATCH 1/2] cpufreq: use strlen() for governor name comparison

Most kernel code using strncasecmp()/strncmp() passes strlen("xxx")
as the length argument. cpufreq_parse_policy() previously used
CPUFREQ_NAME_LEN (16), which is longer than the actual strings
("performance" is 11 chars, "powersave" is 9 chars).

This patch switches to strlen() for the comparison, making the
matching slightly more permissive (e.g., "powersavexxx" will now
also match "powersave"). While this is unlikely to cause functional
issues, it aligns cpufreq with common kernel style and makes the
behavior more intuitive.

Signed-off-by: Zihuan Zhang <zhangzihuan@...inos.cn>
---
 drivers/cpufreq/cpufreq.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index fc7eace8b65b..a067b5447fe8 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -664,10 +664,10 @@ static struct cpufreq_governor *get_governor(const char *str_governor)
 
 static unsigned int cpufreq_parse_policy(char *str_governor)
 {
-	if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN))
+	if (!strncasecmp(str_governor, "performance", strlen("performance")))
 		return CPUFREQ_POLICY_PERFORMANCE;
 
-	if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN))
+	if (!strncasecmp(str_governor, "powersave", strlen("powersave")))
 		return CPUFREQ_POLICY_POWERSAVE;
 
 	return CPUFREQ_POLICY_UNKNOWN;
-- 
2.25.1