Commit 397f2378 authored by Srikar Dronamraju's avatar Srikar Dronamraju Committed by Ingo Molnar
Browse files

sched/numa: Fix numa balancing stats in /proc/pid/sched 



Commit 44dba3d5 ("sched: Refactor task_struct to use
numa_faults instead of numa_* pointers") modified the way
tsk->numa_faults stats are accounted.

However that commit never touched show_numa_stats() that is displayed
in /proc/pid/sched and thus the numbers displayed in /proc/pid/sched
don't match the actual numbers.

Fix it by making sure that /proc/pid/sched reflects the task
fault numbers. Also add group fault stats too.

Also couple of more modifications are added here:

1. Format changes:

  - Previously we would list two entries per node, one for private
    and one for shared. Also the home node info was listed in each entry.

  - Now preferred node, total_faults and current node are
    displayed separately.

  - Now there is one entry per node, that lists private,shared task and
    group faults.

2. Unit changes:

  - p->numa_pages_migrated was getting reset after every read of
    /proc/pid/sched. It's more useful to have absolute numbers since
    differential migrations between two accesses can be more easily
    calculated.

Signed-off-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: default avatarRik van Riel <riel@redhat.com>
Cc: Iulia Manda <iulia.manda21@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1435252903-1081-4-git-send-email-srikar@linux.vnet.ibm.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent e3d24d0a

kernel/sched/debug.c

+17 −21
Original line number Diff line number Diff line
@@ -517,11 +517,21 @@ __initcall(init_sched_debug_procfs); 
	SEQ_printf(m, "%-45s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))





#ifdef CONFIG_NUMA_BALANCING

void print_numa_stats(struct seq_file *m, int node, unsigned long tsf,

		unsigned long tpf, unsigned long gsf, unsigned long gpf)

{

	SEQ_printf(m, "numa_faults node=%d ", node);

	SEQ_printf(m, "task_private=%lu task_shared=%lu ", tsf, tpf);

	SEQ_printf(m, "group_private=%lu group_shared=%lu\n", gsf, gpf);

}

#endif





static void sched_show_numa(struct task_struct *p, struct seq_file *m)

{

#ifdef CONFIG_NUMA_BALANCING

	struct mempolicy *pol;

	int node, i;



	if (p->mm)

		P(mm->numa_scan_seq);
@@ -533,26 +543,12 @@ static void sched_show_numa(struct task_struct *p, struct seq_file *m) 
	mpol_get(pol);

	task_unlock(p);



	SEQ_printf(m, "numa_migrations, %ld\n", xchg(&p->numa_pages_migrated, 0));



	for_each_online_node(node) {

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

			unsigned long nr_faults = -1;

			int cpu_current, home_node;



			if (p->numa_faults)

				nr_faults = p->numa_faults[2*node + i];



			cpu_current = !i ? (task_node(p) == node) :

				(pol && node_isset(node, pol->v.nodes));



			home_node = (p->numa_preferred_nid == node);



			SEQ_printf(m, "numa_faults_memory, %d, %d, %d, %d, %ld\n",

				i, node, cpu_current, home_node, nr_faults);

		}

	}



	P(numa_pages_migrated);

	P(numa_preferred_nid);

	P(total_numa_faults);

	SEQ_printf(m, "current_node=%d, numa_group_id=%d\n",

			task_node(p), task_numa_group_id(p));

	show_numa_stats(p, m);

	mpol_put(pol);

#endif

}

kernel/sched/fair.c

+21 −1
Original line number Diff line number Diff line
@@ -8468,7 +8468,27 @@ void print_cfs_stats(struct seq_file *m, int cpu) 
		print_cfs_rq(m, cpu, cfs_rq);

	rcu_read_unlock();

}

#endif



#ifdef CONFIG_NUMA_BALANCING

void show_numa_stats(struct task_struct *p, struct seq_file *m)

{

	int node;

	unsigned long tsf = 0, tpf = 0, gsf = 0, gpf = 0;



	for_each_online_node(node) {

		if (p->numa_faults) {

			tsf = p->numa_faults[task_faults_idx(NUMA_MEM, node, 0)];

			tpf = p->numa_faults[task_faults_idx(NUMA_MEM, node, 1)];

		}

		if (p->numa_group) {

			gsf = p->numa_group->faults[task_faults_idx(NUMA_MEM, node, 0)],

			gpf = p->numa_group->faults[task_faults_idx(NUMA_MEM, node, 1)];

		}

		print_numa_stats(m, node, tsf, tpf, gsf, gpf);

	}

}

#endif /* CONFIG_NUMA_BALANCING */

#endif /* CONFIG_SCHED_DEBUG */



__init void init_sched_fair_class(void)

{

kernel/sched/sched.h

+9 −1
Original line number Diff line number Diff line
@@ -1675,7 +1675,15 @@ extern void print_rt_stats(struct seq_file *m, int cpu); 
extern void print_dl_stats(struct seq_file *m, int cpu);

extern void

print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);

#endif



#ifdef CONFIG_NUMA_BALANCING

extern void

show_numa_stats(struct task_struct *p, struct seq_file *m);

extern void

print_numa_stats(struct seq_file *m, int node, unsigned long tsf,

	unsigned long tpf, unsigned long gsf, unsigned long gpf);

#endif /* CONFIG_NUMA_BALANCING */

#endif /* CONFIG_SCHED_DEBUG */



extern void init_cfs_rq(struct cfs_rq *cfs_rq);

extern void init_rt_rq(struct rt_rq *rt_rq);

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