diff mbox series

[v3,3/3] cpufreq: mediatek: data safety protect

Message ID 20250214074353.1169864-4-chun-jen.tseng@mediatek.com (mailing list archive)
State New
Headers show
Series fixed mediatek-cpufreq has multi policy concurrency issue | expand

Commit Message

Mark Tseng Feb. 14, 2025, 7:43 a.m. UTC 
get policy data in global lock session avoid get wrong data.

Signed-off-by: Mark Tseng <chun-jen.tseng@mediatek.com>
---
 drivers/cpufreq/mediatek-cpufreq.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

Comments

Viresh Kumar Feb. 19, 2025, 5:49 a.m. UTC | #1 
On 14-02-25, 15:43, Mark Tseng wrote:
> get policy data in global lock session avoid get wrong data.
> 
> Signed-off-by: Mark Tseng <chun-jen.tseng@mediatek.com>
> ---
>  drivers/cpufreq/mediatek-cpufreq.c | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)

I think there is some confusion on why exactly locking is required and where
exactly you need it. This patch is incorrect.

If you really think some locking issue is present here, please explain in
detail how a race can happen between different threads.
diff mbox series

Patch

diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c
index 68fcb6fcbe48..37b929e81f70 100644
--- a/drivers/cpufreq/mediatek-cpufreq.c
+++ b/drivers/cpufreq/mediatek-cpufreq.c
@@ -201,11 +201,11 @@  static bool is_ccifreq_ready(struct mtk_cpu_dvfs_info *info)
 static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 				  unsigned int index)
 {
-	struct cpufreq_frequency_table *freq_table = policy->freq_table;
-	struct clk *cpu_clk = policy->clk;
-	struct clk *armpll = clk_get_parent(cpu_clk);
-	struct mtk_cpu_dvfs_info *info = policy->driver_data;
-	struct device *cpu_dev = info->cpu_dev;
+	struct cpufreq_frequency_table *freq_table;
+	struct clk *cpu_clk;
+	struct clk *armpll;
+	struct mtk_cpu_dvfs_info *info;
+	struct device *cpu_dev;
 	struct dev_pm_opp *opp;
 	long freq_hz, pre_freq_hz;
 	int vproc, pre_vproc, inter_vproc, target_vproc, ret;
@@ -213,6 +213,11 @@  static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
 
 	mutex_lock(&mtk_policy_lock);
 
+	freq_table = policy->freq_table;
+	cpu_clk = policy->clk;
+	armpll = clk_get_parent(cpu_clk);
+	info = policy->driver_data;
+	cpu_dev = info->cpu_dev;
 	inter_vproc = info->intermediate_voltage;
 	pre_freq_hz = policy->cur * 1000;