From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: [PATCH v9 15/20] mm/mlock: optimize munlock_pagevec by relocking Date: Mon, 2 Mar 2020 19:00:25 +0800 Message-ID: <1583146830-169516-16-git-send-email-alex.shi@linux.alibaba.com> References: <1583146830-169516-1-git-send-email-alex.shi@linux.alibaba.com> Return-path: In-Reply-To: <1583146830-169516-1-git-send-email-alex.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, mgorman-3eNAlZScCAx27rWaFMvyedHuzzzSOjJt@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, hughd-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, khlebnikov-XoJtRXgx1JseBXzfvpsJ4g@public.gmane.org, daniel.m.jordan-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, yang.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org, willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org Cc: Alex Shi , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org During the pagevec locking, a new page's lruvec is may same as previous one. Thus we could save a re-locking, and only change lock iff lruvec is newer. Signed-off-by: Alex Shi Cc: Andrew Morton Cc: Johannes Weiner Cc: Hugh Dickins Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org --- mm/mlock.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/mlock.c b/mm/mlock.c index d285348b147e..236a29b791f4 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -281,6 +281,7 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) int nr = pagevec_count(pvec); int delta_munlocked = -nr; struct pagevec pvec_putback; + struct lruvec *lruvec = NULL; int pgrescued = 0; pagevec_init(&pvec_putback); @@ -288,7 +289,6 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) /* Phase 1: page isolation */ for (i = 0; i < nr; i++) { struct page *page = pvec->pages[i]; - struct lruvec *lruvec; if (!TestClearPageMlocked(page)) { delta_munlocked++; @@ -305,9 +305,8 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) * We already have pin from follow_page_mask() * so we can spare the get_page() here. */ - lruvec = lock_page_lruvec_irq(page); + lruvec = relock_page_lruvec_irq(page, lruvec); del_page_from_lru_list(page, lruvec, page_lru(page)); - unlock_page_lruvec_irq(lruvec); continue; /* @@ -320,6 +319,8 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) pagevec_add(&pvec_putback, pvec->pages[i]); pvec->pages[i] = NULL; } + if (lruvec) + unlock_page_lruvec_irq(lruvec); __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked); /* Now we can release pins of pages that we are not munlocking */ -- 1.8.3.1