Unverified Commit 0d704970 authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!992 [sync] PR-949: mm: page_counter: remove unneeded atomic ops for low/min 

Merge Pull Request from: @openeuler-sync-bot 
 

Origin pull request: 
https://gitee.com/openeuler/kernel/pulls/949 
 
PR sync from:  Peng Zhang <zhangpeng362@huawei.com>
 https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/thread/KYRABPTSB6EKOTCKUIGSLAPKEFA5O5FS/ 
 
 
Link:https://gitee.com/openeuler/kernel/pulls/992

 

Reviewed-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parents 3f6af508 831d54ee

mm/page_counter.c

+6 −7
Original line number Diff line number Diff line
@@ -17,24 +17,23 @@ static void propagate_protected_usage(struct page_counter *c, 
				      unsigned long usage)

{

	unsigned long protected, old_protected;

	unsigned long low, min;

	long delta;



	if (!c->parent)

		return;



	min = READ_ONCE(c->min);

	if (min || atomic_long_read(&c->min_usage)) {

		protected = min(usage, min);

	protected = min(usage, READ_ONCE(c->min));

	old_protected = atomic_long_read(&c->min_usage);

	if (protected != old_protected) {

		old_protected = atomic_long_xchg(&c->min_usage, protected);

		delta = protected - old_protected;

		if (delta)

			atomic_long_add(delta, &c->parent->children_min_usage);

	}



	low = READ_ONCE(c->low);

	if (low || atomic_long_read(&c->low_usage)) {

		protected = min(usage, low);

	protected = min(usage, READ_ONCE(c->low));

	old_protected = atomic_long_read(&c->low_usage);

	if (protected != old_protected) {

		old_protected = atomic_long_xchg(&c->low_usage, protected);

		delta = protected - old_protected;

		if (delta)