Commit e7fcd762 authored by Chengming Zhou's avatar Chengming Zhou Committed by Ingo Molnar
Browse files

psi: Add PSI_CPU_FULL state 



The FULL state doesn't exist for the CPU resource at the system level,
but exist at the cgroup level, means all non-idle tasks in a cgroup are
delayed on the CPU resource which used by others outside of the cgroup
or throttled by the cgroup cpu.max configuration.

Co-developed-by: default avatarMuchun Song <songmuchun@bytedance.com>
Signed-off-by: default avatarMuchun Song <songmuchun@bytedance.com>
Signed-off-by: default avatarChengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Acked-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/20210303034659.91735-2-zhouchengming@bytedance.com
parent 585b6d27

include/linux/psi_types.h

+2 −1
Original line number Diff line number Diff line
@@ -50,9 +50,10 @@ enum psi_states { 
	PSI_MEM_SOME,

	PSI_MEM_FULL,

	PSI_CPU_SOME,

	PSI_CPU_FULL,

	/* Only per-CPU, to weigh the CPU in the global average: */

	PSI_NONIDLE,

	NR_PSI_STATES = 6,

	NR_PSI_STATES = 7,

};



enum psi_aggregators {

kernel/sched/psi.c

+11 −3
Original line number Diff line number Diff line
@@ -34,7 +34,10 @@ 
 * delayed on that resource such that nobody is advancing and the CPU

 * goes idle. This leaves both workload and CPU unproductive.

 *

 * (Naturally, the FULL state doesn't exist for the CPU resource.)

 * Naturally, the FULL state doesn't exist for the CPU resource at the

 * system level, but exist at the cgroup level, means all non-idle tasks

 * in a cgroup are delayed on the CPU resource which used by others outside

 * of the cgroup or throttled by the cgroup cpu.max configuration.

 *

 *	SOME = nr_delayed_tasks != 0

 *	FULL = nr_delayed_tasks != 0 && nr_running_tasks == 0
@@ -225,6 +228,8 @@ static bool test_state(unsigned int *tasks, enum psi_states state) 
		return tasks[NR_MEMSTALL] && !tasks[NR_RUNNING];

	case PSI_CPU_SOME:

		return tasks[NR_RUNNING] > tasks[NR_ONCPU];

	case PSI_CPU_FULL:

		return tasks[NR_RUNNING] && !tasks[NR_ONCPU];

	case PSI_NONIDLE:

		return tasks[NR_IOWAIT] || tasks[NR_MEMSTALL] ||

			tasks[NR_RUNNING];
@@ -678,8 +683,11 @@ static void record_times(struct psi_group_cpu *groupc, int cpu, 
		}

	}



	if (groupc->state_mask & (1 << PSI_CPU_SOME))

	if (groupc->state_mask & (1 << PSI_CPU_SOME)) {

		groupc->times[PSI_CPU_SOME] += delta;

		if (groupc->state_mask & (1 << PSI_CPU_FULL))

			groupc->times[PSI_CPU_FULL] += delta;

	}



	if (groupc->state_mask & (1 << PSI_NONIDLE))

		groupc->times[PSI_NONIDLE] += delta;
@@ -1018,7 +1026,7 @@ int psi_show(struct seq_file *m, struct psi_group *group, enum psi_res res) 
		group->avg_next_update = update_averages(group, now);

	mutex_unlock(&group->avgs_lock);



	for (full = 0; full < 2 - (res == PSI_CPU); full++) {

	for (full = 0; full < 2; full++) {

		unsigned long avg[3];

		u64 total;

		int w;