From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: [PATCH v7 05/10] mm/mlock: optimize munlock_pagevec by relocking Date: Wed, 25 Dec 2019 17:04:21 +0800 Message-ID: <1577264666-246071-6-git-send-email-alex.shi@linux.alibaba.com> References: <1577264666-246071-1-git-send-email-alex.shi@linux.alibaba.com> Return-path: In-Reply-To: <1577264666-246071-1-git-send-email-alex.shi@linux.alibaba.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, yang.shi@linux.alibaba.com, willy@infradead.org, shakeelb@google.com, hannes@cmpxchg.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: Johannes Weiner Cc: Hugh Dickins Cc: linux-kernel@vger.kernel.org Cc: cgroups@vger.kernel.org Cc: linux-mm@kvack.org Cc: Andrew Morton --- mm/mlock.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/mm/mlock.c b/mm/mlock.c index 10d15f58b061..050f999eadb1 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -289,6 +289,7 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) { int i; int nr = pagevec_count(pvec); + int delta_munlocked = -nr; struct pagevec pvec_putback; struct lruvec *lruvec = NULL; int pgrescued = 0; @@ -299,20 +300,19 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) for (i = 0; i < nr; i++) { struct page *page = pvec->pages[i]; - lruvec = lock_page_lruvec_irq(page); + lruvec = relock_page_lruvec_irq(page, lruvec); if (TestClearPageMlocked(page)) { /* * We already have pin from follow_page_mask() * so we can spare the get_page() here. */ - if (__munlock_isolate_lru_page(page, lruvec, false)) { - __mod_zone_page_state(zone, NR_MLOCK, -1); - unlock_page_lruvec_irq(lruvec); + if (__munlock_isolate_lru_page(page, lruvec, false)) continue; - } else + else __munlock_isolation_failed(page); - } + } else + delta_munlocked++; /* * We won't be munlocking this page in the next phase @@ -322,8 +322,10 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) */ pagevec_add(&pvec_putback, pvec->pages[i]); pvec->pages[i] = NULL; - unlock_page_lruvec_irq(lruvec); } + __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked); + if (lruvec) + unlock_page_lruvec_irq(lruvec); /* Now we can release pins of pages that we are not munlocking */ pagevec_release(&pvec_putback); -- 1.8.3.1