Merge "memcg: make mem_cgroup_read_{stat|event}() iterate possible cpus instead of online" (a5caa42a) · Commits · e / devices / android_kernel_xiaomi_markw

mm/memcontrol.c

+2 −49

Original line number	Diff line number	Diff line
		@@ -345,11 +345,6 @@ struct mem_cgroup {
		* percpu counter.
		*/
		struct mem_cgroup_stat_cpu __percpu *stat;
		/*
		* used when a cpu is offlined or other synchronizations
		* See mem_cgroup_read_stat().
		*/
		struct mem_cgroup_stat_cpu nocpu_base;
		spinlock_t pcp_counter_lock;

		atomic_t dead_count;
		@@ -868,15 +863,8 @@ static long mem_cgroup_read_stat(struct mem_cgroup *memcg,
		long val = 0;
		int cpu;

		get_online_cpus();
		for_each_online_cpu(cpu)
		for_each_possible_cpu(cpu)
		val += per_cpu(memcg->stat->count[idx], cpu);
		#ifdef CONFIG_HOTPLUG_CPU
		spin_lock(&memcg->pcp_counter_lock);
		val += memcg->nocpu_base.count[idx];
		spin_unlock(&memcg->pcp_counter_lock);
		#endif
		put_online_cpus();
		return val;
		}

		@@ -886,15 +874,8 @@ static unsigned long mem_cgroup_read_events(struct mem_cgroup *memcg,
		unsigned long val = 0;
		int cpu;

		get_online_cpus();
		for_each_online_cpu(cpu)
		for_each_possible_cpu(cpu)
		val += per_cpu(memcg->stat->events[idx], cpu);
		#ifdef CONFIG_HOTPLUG_CPU
		spin_lock(&memcg->pcp_counter_lock);
		val += memcg->nocpu_base.events[idx];
		spin_unlock(&memcg->pcp_counter_lock);
		#endif
		put_online_cpus();
		return val;
		}

		@@ -2454,37 +2435,12 @@ static void drain_all_stock_sync(struct mem_cgroup *root_memcg)
		mutex_unlock(&percpu_charge_mutex);
		}

		/*
		* This function drains percpu counter value from DEAD cpu and
		* move it to local cpu. Note that this function can be preempted.
		*/
		static void mem_cgroup_drain_pcp_counter(struct mem_cgroup *memcg, int cpu)
		{
		int i;

		spin_lock(&memcg->pcp_counter_lock);
		for (i = 0; i < MEM_CGROUP_STAT_NSTATS; i++) {
		long x = per_cpu(memcg->stat->count[i], cpu);

		per_cpu(memcg->stat->count[i], cpu) = 0;
		memcg->nocpu_base.count[i] += x;
		}
		for (i = 0; i < MEM_CGROUP_EVENTS_NSTATS; i++) {
		unsigned long x = per_cpu(memcg->stat->events[i], cpu);

		per_cpu(memcg->stat->events[i], cpu) = 0;
		memcg->nocpu_base.events[i] += x;
		}
		spin_unlock(&memcg->pcp_counter_lock);
		}

		static int memcg_cpu_hotplug_callback(struct notifier_block *nb,
		unsigned long action,
		void *hcpu)
		{
		int cpu = (unsigned long)hcpu;
		struct memcg_stock_pcp *stock;
		struct mem_cgroup *iter;

		if (action == CPU_ONLINE)
		return NOTIFY_OK;
		@@ -2492,9 +2448,6 @@ static int memcg_cpu_hotplug_callback(struct notifier_block *nb,
		if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
		return NOTIFY_OK;

		for_each_mem_cgroup(iter)
		mem_cgroup_drain_pcp_counter(iter, cpu);

		stock = &per_cpu(memcg_stock, cpu);
		drain_stock(stock);
		return NOTIFY_OK;