cpu_hotplug: fix dead lock between flush work and ipa [1/1]

PD#TV-7161

Problem:
dead lock between flush work and ipa

Solution:
fix dead lock between flush work and ipa

Verify:
TL1

Change-Id: I479869601c0816bbaeaa693a26bf606b6a168da0
Signed-off-by: Jianxin Pan <jianxin.pan@amlogic.com>

diff --git a/drivers/amlogic/cpu_hotplug/cpu_hotplug.c b/drivers/amlogic/cpu_hotplug/cpu_hotplug.c
index 8010e88..3df6617 100644 (file)
--- a/drivers/amlogic/cpu_hotplug/cpu_hotplug.c
+++ b/drivers/amlogic/cpu_hotplug/cpu_hotplug.c
@@ -33,6 +33,7 @@
 #include <linux/sched/rt.h>
 #include <linux/notifier.h>
 #include "linux/amlogic/cpu_hotplug.h"
+#include <linux/delay.h>
 
 #define MAX_CLUSTRS            2
 struct cpu_hotplug_s {
@@ -102,7 +103,8 @@ void cpu_hotplug_set_max(unsigned int num, int clustr)
                return;
        }
 
-       mutex_lock(&hpg.mutex);
+       if (!mutex_trylock(&hpg.mutex))
+               return;
        if (num > hpg.cpunum[clustr])
                num = hpg.cpunum[clustr];
        if (hpg.max_num[clustr] == num) {
@@ -157,7 +159,10 @@ static int __ref cpu_hotplug_thread(void *data)
        while (1) {
                if (kthread_should_stop())
                        break;
-               mutex_lock(&hpg.mutex);
+               if (!mutex_trylock(&hpg.mutex)) {
+                       usleep_range(1000, 2000);
+                       continue;
+               }
                for (clustr = 0; clustr < hpg.clusters; clustr++) {
                        if (!hpg.flgs[clustr])
                                continue;