From: Sri Krishna chowdary <schowdary@xxxxxxxxxx>
Kmemleak scan is cpu intensive and can stall user tasks at times.
To prevent this, add config DEBUG_KMEMLEAK_SCAN_ON to enable/disable
auto scan on boot up.
Also protect first_run with CONFIG_DEBUG_KMEMLEAK_SCAN_ON as this is
meant for only first automatic scan.
Signed-off-by: Sri Krishna chowdary <schowdary@xxxxxxxxxx>
Signed-off-by: Sachin Nikam <snikam@xxxxxxxxxx>
Signed-off-by: Prateek <prpatel@xxxxxxxxxx>
---
lib/Kconfig.debug | 11 +++++++++++
mm/kmemleak.c | 6 ++++++
2 files changed, 17 insertions(+)
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e5e7c03..9542852 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -593,6 +593,17 @@ config DEBUG_KMEMLEAK_DEFAULT_OFF
Say Y here to disable kmemleak by default. It can then be enabled
on the command line via kmemleak=on.
+config DEBUG_KMEMLEAK_SCAN_ON
+ bool "Enable kmemleak auto scan thread on boot up"
+ default y
+ depends on DEBUG_KMEMLEAK
+ help
+ Kmemleak scan is cpu intensive and can stall user tasks at times.
+ This option enables/disables automatic kmemleak scan at boot up.
+
+ Say N here to disable kmemleak auto scan thread to stop automatic
+ scanning.
+
config DEBUG_STACK_USAGE
bool "Stack utilization instrumentation"
depends on DEBUG_KERNEL && !IA64
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 877de4f..ac53678 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -1647,11 +1647,14 @@ static void kmemleak_scan(void)
*/
static int kmemleak_scan_thread(void *arg)
{
+#ifdef CONFIG_DEBUG_KMEMLEAK_SCAN_ON
static int first_run = 1;
+#endif
pr_info("Automatic memory scanning thread started\n");
set_user_nice(current, 10);
+#ifdef CONFIG_DEBUG_KMEMLEAK_SCAN_ON
/*
* Wait before the first scan to allow the system to fully initialize.
*/
@@ -1661,6 +1664,7 @@ static int kmemleak_scan_thread(void *arg)
while (timeout && !kthread_should_stop())
timeout = schedule_timeout_interruptible(timeout);
}
+#endif
while (!kthread_should_stop()) {
signed long timeout = jiffies_scan_wait;
@@ -2141,9 +2145,11 @@ static int __init kmemleak_late_init(void)
return -ENOMEM;
}
+#ifdef CONFIG_DEBUG_KMEMLEAK_SCAN_ON
mutex_lock(&scan_mutex);
start_scan_thread();
mutex_unlock(&scan_mutex);
+#endif
pr_info("Kernel memory leak detector initialized\n");
--
2.1.4
