Commit 51973cc9 authored by Kinsey Ho's avatar Kinsey Ho Committed by Andrew Morton
Browse files

mm/mglru: improve should_run_aging() 

scan_control *sc does not need to be passed into should_run_aging(), as it
provides only the reclaim priority.  This can be moved to
get_nr_to_scan().

Refactor should_run_aging() and get_nr_to_scan() to improve code
readability.  No functional changes.

Link: https://lkml.kernel.org/r/20240214060538.3524462-3-kinseyho@google.com


Signed-off-by: default avatarKinsey Ho <kinseyho@google.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Donet Tom <donettom@linux.vnet.ibm.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 1ce2292c

mm/vmscan.c

+11 −14
Original line number Diff line number Diff line
@@ -4584,14 +4584,13 @@ static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swap 
}



static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq,

			     struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan)

			     bool can_swap, unsigned long *nr_to_scan)

{

	int gen, type, zone;

	unsigned long old = 0;

	unsigned long young = 0;

	unsigned long total = 0;

	struct lru_gen_folio *lrugen = &lruvec->lrugen;

	struct mem_cgroup *memcg = lruvec_memcg(lruvec);

	DEFINE_MIN_SEQ(lruvec);



	/* whether this lruvec is completely out of cold folios */
@@ -4619,13 +4618,7 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, 
		}

	}



	/* try to scrape all its memory if this memcg was deleted */

	if (!mem_cgroup_online(memcg)) {

	*nr_to_scan = total;

		return false;

	}



	*nr_to_scan = total >> sc->priority;



	/*

	 * The aging tries to be lazy to reduce the overhead, while the eviction
@@ -4657,6 +4650,7 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, 
 */

static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, bool can_swap)

{

	bool success;

	unsigned long nr_to_scan;

	struct mem_cgroup *memcg = lruvec_memcg(lruvec);

	DEFINE_MAX_SEQ(lruvec);
@@ -4664,14 +4658,17 @@ static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, bool 
	if (mem_cgroup_below_min(sc->target_mem_cgroup, memcg))

		return -1;



	if (!should_run_aging(lruvec, max_seq, sc, can_swap, &nr_to_scan))

		return nr_to_scan;

	success = should_run_aging(lruvec, max_seq, can_swap, &nr_to_scan);



	/* skip the aging path at the default priority */

	if (sc->priority == DEF_PRIORITY)

	/* try to scrape all its memory if this memcg was deleted */

	if (nr_to_scan && !mem_cgroup_online(memcg))

		return nr_to_scan;



	/* skip this lruvec as it's low on cold folios */

	/* try to get away with not aging at the default priority */

	if (!success || sc->priority == DEF_PRIORITY)

		return nr_to_scan >> sc->priority;



	/* stop scanning this lruvec as it's low on cold folios */

	return try_to_inc_max_seq(lruvec, max_seq, can_swap, false) ? -1 : 0;

}