From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: [PATCH v7 04/10] mm/lru: introduce the relock_page_lruvec function Date: Wed, 25 Dec 2019 17:04:20 +0800 Message-ID: <1577264666-246071-5-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 Cc: Michal Hocko , Vladimir Davydov , Roman Gushchin , Chris Down , Thomas Gleixner , Vlastimil Babka , Andrey Ryabinin , swkhack , "Potyra, Stefan" , Jason Gunthorpe , Mauro Carvalho Chehab , Peng Fan , Nikolay Borisov , Ira Weiny , Kirill Tkhai , Yafang Shao During the lruvec 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 new. Function named relock_page_lruvec following Hugh Dickins' patch. Signed-off-by: Alex Shi Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Andrew Morton Cc: Roman Gushchin Cc: Shakeel Butt Cc: Chris Down Cc: Thomas Gleixner Cc: Vlastimil Babka Cc: Andrey Ryabinin Cc: swkhack Cc: "Potyra, Stefan" Cc: Jason Gunthorpe Cc: Matthew Wilcox Cc: Mauro Carvalho Chehab Cc: Peng Fan Cc: Nikolay Borisov Cc: Ira Weiny Cc: Kirill Tkhai Cc: Yang Shi Cc: Yafang Shao Cc: Mel Gorman Cc: Konstantin Khlebnikov Cc: Hugh Dickins Cc: Tejun Heo Cc: linux-kernel@vger.kernel.org Cc: cgroups@vger.kernel.org Cc: linux-mm@kvack.org --- include/linux/memcontrol.h | 36 ++++++++++++++++++++++++++++++++++++ mm/vmscan.c | 8 ++------ 2 files changed, 38 insertions(+), 6 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 8389b9b927ef..09e861df48e8 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1299,6 +1299,42 @@ static inline void dec_lruvec_page_state(struct page *page, mod_lruvec_page_state(page, idx, -1); } +/* Don't lock again iff page's lruvec locked */ +static inline struct lruvec *relock_page_lruvec_irq(struct page *page, + struct lruvec *locked_lruvec) +{ + struct pglist_data *pgdat = page_pgdat(page); + struct lruvec *lruvec; + + lruvec = mem_cgroup_page_lruvec(page, pgdat); + + if (likely(locked_lruvec == lruvec)) + return lruvec; + + if (unlikely(locked_lruvec)) + unlock_page_lruvec_irq(locked_lruvec); + + return lock_page_lruvec_irq(page); +} + +/* Don't lock again iff page's lruvec locked */ +static inline struct lruvec *relock_page_lruvec_irqsave(struct page *page, + struct lruvec *locked_lruvec, unsigned long *flags) +{ + struct pglist_data *pgdat = page_pgdat(page); + struct lruvec *lruvec; + + lruvec = mem_cgroup_page_lruvec(page, pgdat); + + if (likely(locked_lruvec == lruvec)) + return lruvec; + + if (unlikely(locked_lruvec)) + unlock_page_lruvec_irqrestore(locked_lruvec, *flags); + + return lock_page_lruvec_irqsave(page, flags); +} + #ifdef CONFIG_CGROUP_WRITEBACK struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb); diff --git a/mm/vmscan.c b/mm/vmscan.c index a97e35675286..a1d34ca1505e 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4342,14 +4342,10 @@ void check_move_unevictable_pages(struct pagevec *pvec) for (i = 0; i < pvec->nr; i++) { struct page *page = pvec->pages[i]; - struct lruvec *new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); pgscanned++; - if (lruvec != new_lruvec) { - if (lruvec) - unlock_page_lruvec_irq(lruvec); - lruvec = lock_page_lruvec_irq(page); - } + + lruvec = relock_page_lruvec_irq(page, lruvec); if (!PageLRU(page) || !PageUnevictable(page)) continue; -- 1.8.3.1