[PATCH 5.4 03/47] thermal/drivers/cpufreq_cooling: Update cpufreq_state only if state has changed

From: Greg Kroah-Hartman
Date: Mon Jan 04 2021 - 11:13:02 EST


From: Zhuguangqing <zhuguangqing@xxxxxxxxxx>

commit 236761f19a4f373354f1dcf399b57753f1f4b871 upstream.

If state has not changed successfully and we updated cpufreq_state,
next time when the new state is equal to cpufreq_state (not changed
successfully last time), we will return directly and miss a
freq_qos_update_request() that should have been.

Fixes: 5130802ddbb1 ("thermal: cpu_cooling: Switch to QoS requests for freq limits")
Cc: v5.4+ <stable@xxxxxxxxxxxxxxx> # v5.4+
Signed-off-by: Zhuguangqing <zhuguangqing@xxxxxxxxxx>
Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20201106092243.15574-1-zhuguangqing83@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/thermal/cpu_cooling.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -320,6 +320,7 @@ static int cpufreq_set_cur_state(struct
unsigned long state)
{
struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata;
+ int ret;

/* Request state should be less than max_level */
if (WARN_ON(state > cpufreq_cdev->max_level))
@@ -329,10 +330,12 @@ static int cpufreq_set_cur_state(struct
if (cpufreq_cdev->cpufreq_state == state)
return 0;

- cpufreq_cdev->cpufreq_state = state;
+ ret = freq_qos_update_request(&cpufreq_cdev->qos_req,
+ cpufreq_cdev->freq_table[state].frequency);
+ if (ret > 0)
+ cpufreq_cdev->cpufreq_state = state;

- return freq_qos_update_request(&cpufreq_cdev->qos_req,
- cpufreq_cdev->freq_table[state].frequency);
+ return ret;
}

/**