Merge "mm: oom: ensure emergency trigger is raised before enter into oom" (ca08ca1b) · Commits · e / devices / android_kernel_oneplus_sm7250

mm/oom_kill.c

+10 −4

Original line number	Diff line number	Diff line
		@@ -80,6 +80,7 @@ DEFINE_MUTEX(oom_lock);

		/* The maximum amount of time to loop in should_ulmk_retry() */
		#define ULMK_TIMEOUT (20 * HZ)
		#define ULMK_EMERG_TRIG_TIMEOUT (ULMK_TIMEOUT + 10 * HZ)

		#define ULMK_DBG_POLICY_TRIGGER (BIT(0))
		#define ULMK_DBG_POLICY_WDOG (BIT(1))
		@@ -92,6 +93,7 @@ static atomic64_t ulmk_wdog_expired = ATOMIC64_INIT(0);
		static atomic64_t ulmk_kill_jiffies = ATOMIC64_INIT(INITIAL_JIFFIES);
		static atomic64_t ulmk_watchdog_pet_jiffies = ATOMIC64_INIT(INITIAL_JIFFIES);
		static unsigned long psi_emergency_jiffies = INITIAL_JIFFIES;
		static unsigned long psi_emerg_trigger_jiffies = INITIAL_JIFFIES;
		/* Prevents contention on the mutex_trylock in psi_emergency_jiffies */
		static DEFINE_MUTEX(ulmk_retry_lock);

		@@ -170,9 +172,10 @@ bool should_ulmk_retry(gfp_t gfp_mask)
		* current time and return true.
		*
		* b) If no kill have had happened in the last ULMK_TIMEOUT and
		* LMKD also stuck for the last ULMK_TIMEOUT, which then means
		* that system kill logic is not responding despite PSI events
		* sent from kernel. Return false.
		* LMKD also stuck for the last ULMK_TIMEOUT despite an
		* emergency trigger in the last ULMK_EMERG_TRIG_TIMEOUT, which
		* then means that system kill logic is not responding despite
		* PSI events sent from kernel. Return false.
		*
		* c) Cond1: trigger = !active && wdog_expired = false:
		* Then give a chance to the ULMK by raising emergnecy trigger
		@@ -199,11 +202,14 @@ bool should_ulmk_retry(gfp_t gfp_mask)
		psi_emergency_jiffies = now;
		ret = true;
		} else if (time_after(now, psi_emergency_jiffies + ULMK_TIMEOUT) &&
		time_after(now, last_wdog_pet + ULMK_TIMEOUT)) {
		time_after(now, last_wdog_pet + ULMK_TIMEOUT) &&
		time_after(psi_emerg_trigger_jiffies,
		now - ULMK_EMERG_TRIG_TIMEOUT)) {
		ret = false;
		} else if (!trigger_active) {
		BUG_ON(ulmk_dbg_policy & ULMK_DBG_POLICY_TRIGGER);
		psi_emergency_trigger();
		psi_emerg_trigger_jiffies = now;
		ret = true;
		} else if (wdog_expired) {
		mutex_lock(&oom_lock);