Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit af1839d7 authored by Mel Gorman's avatar Mel Gorman Committed by Linus Torvalds
Browse files

mm: numa: trace tasks that fail migration due to rate limiting 



A low local/remote numa hinting fault ratio is potentially explained by
failed migrations.  This patch adds a tracepoint that fires when
migration fails due to migration rate limitation.

Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
Reviewed-by: default avatarRik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 1c5e9c27

include/trace/events/migrate.h

+26 −0
Original line number Diff line number Diff line
@@ -45,6 +45,32 @@ TRACE_EVENT(mm_migrate_pages, 
		__print_symbolic(__entry->reason, MIGRATE_REASON))

);



TRACE_EVENT(mm_numa_migrate_ratelimit,



	TP_PROTO(struct task_struct *p, int dst_nid, unsigned long nr_pages),



	TP_ARGS(p, dst_nid, nr_pages),



	TP_STRUCT__entry(

		__array(	char,		comm,	TASK_COMM_LEN)

		__field(	pid_t,		pid)

		__field(	int,		dst_nid)

		__field(	unsigned long,	nr_pages)

	),



	TP_fast_assign(

		memcpy(__entry->comm, p->comm, TASK_COMM_LEN);

		__entry->pid		= p->pid;

		__entry->dst_nid	= dst_nid;

		__entry->nr_pages	= nr_pages;

	),



	TP_printk("comm=%s pid=%d dst_nid=%d nr_pages=%lu",

		__entry->comm,

		__entry->pid,

		__entry->dst_nid,

		__entry->nr_pages)

);

#endif /* _TRACE_MIGRATE_H */



/* This part must be outside protection */

mm/migrate.c

+4 −1
Original line number Diff line number Diff line
@@ -1614,8 +1614,11 @@ static bool numamigrate_update_ratelimit(pg_data_t *pgdat, 
			msecs_to_jiffies(migrate_interval_millisecs);

		spin_unlock(&pgdat->numabalancing_migrate_lock);

	}

	if (pgdat->numabalancing_migrate_nr_pages > ratelimit_pages)

	if (pgdat->numabalancing_migrate_nr_pages > ratelimit_pages) {

		trace_mm_numa_migrate_ratelimit(current, pgdat->node_id,

								nr_pages);

		return true;

	}



	/*

	 * This is an unlocked non-atomic update so errors are possible.