From patchwork Thu Nov 5 08:55:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Shi X-Patchwork-Id: 11883711 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3E5DF921 for ; Thu, 5 Nov 2020 08:56:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E29FD206FB for ; Thu, 5 Nov 2020 08:56:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E29FD206FB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5F6BE6B00C3; Thu, 5 Nov 2020 03:56:34 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 57B416B00C4; Thu, 5 Nov 2020 03:56:34 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3AB0D6B00C5; Thu, 5 Nov 2020 03:56:34 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0134.hostedemail.com [216.40.44.134]) by kanga.kvack.org (Postfix) with ESMTP id EFCB56B00C3 for ; Thu, 5 Nov 2020 03:56:33 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id A04BE180AD811 for ; Thu, 5 Nov 2020 08:56:33 +0000 (UTC) X-FDA: 77449758666.09.bun90_070134d272c8 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin09.hostedemail.com (Postfix) with ESMTP id 83E15180AD80F for ; Thu, 5 Nov 2020 08:56:33 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,alex.shi@linux.alibaba.com,,RULES_HIT:30012:30054:30056:30070,0,RBL:47.88.44.36:@linux.alibaba.com:.lbl8.mailshell.net-64.10.201.10 62.18.0.100;04yfmtrbpz86eik8x5wos31w6jys8opz78u9cfhsi7dxbndfdqzcddumzwnarsr.zmqjrwh5339y5ruhjqfya5g66dxjg6rge54kd84qb9srubx7ffkabxoqfjb3hs6.h-lbl8.mailshell.net-223.238.255.100;47.88.44.36-irl.urbl.hostedemail.com-127.0.0.150,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:69,LUA_SUMMARY:none X-HE-Tag: bun90_070134d272c8 X-Filterd-Recvd-Size: 9548 Received: from out4436.biz.mail.alibaba.com (out4436.biz.mail.alibaba.com [47.88.44.36]) by imf10.hostedemail.com (Postfix) with ESMTP for ; Thu, 5 Nov 2020 08:56:32 +0000 (UTC) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R381e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=24;SR=0;TI=SMTPD_---0UEJC3Fv_1604566567; Received: from aliy80.localdomain(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0UEJC3Fv_1604566567) by smtp.aliyun-inc.com(127.0.0.1); Thu, 05 Nov 2020 16:56:15 +0800 From: Alex Shi To: akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, willy@infradead.org, hannes@cmpxchg.org, lkp@intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, shakeelb@google.com, iamjoonsoo.kim@lge.com, richard.weiyang@gmail.com, kirill@shutemov.name, alexander.duyck@gmail.com, rong.a.chen@intel.com, mhocko@suse.com, vdavydov.dev@gmail.com, shy828301@gmail.com Cc: Alexander Duyck , Thomas Gleixner , Andrey Ryabinin Subject: [PATCH v21 18/19] mm/lru: introduce the relock_page_lruvec function Date: Thu, 5 Nov 2020 16:55:48 +0800 Message-Id: <1604566549-62481-19-git-send-email-alex.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1604566549-62481-1-git-send-email-alex.shi@linux.alibaba.com> References: <1604566549-62481-1-git-send-email-alex.shi@linux.alibaba.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Alexander Duyck Use this new function to replace repeated same code, no func change. When testing for relock we can avoid the need for RCU locking if we simply compare the page pgdat and memcg pointers versus those that the lruvec is holding. By doing this we can avoid the extra pointer walks and accesses of the memory cgroup. In addition we can avoid the checks entirely if lruvec is currently NULL. Signed-off-by: Alexander Duyck Signed-off-by: Alex Shi Acked-by: Hugh Dickins Acked-by: Johannes Weiner Cc: Johannes Weiner Cc: Andrew Morton Cc: Thomas Gleixner Cc: Andrey Ryabinin Cc: Matthew Wilcox 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 Signed-off-by: Alexander Duyck Signed-off-by: Alex Shi Acked-by: Hugh Dickins Acked-by: Johannes Weiner Acked-by: Johannes Weiner Acked-by: Vlastimil Babka --- include/linux/memcontrol.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++ mm/mlock.c | 11 +--------- mm/swap.c | 33 +++++++---------------------- mm/vmscan.c | 12 ++--------- 4 files changed, 62 insertions(+), 46 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 6ecb08ff4ad1..ba4050154fea 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -660,6 +660,22 @@ static inline struct lruvec *mem_cgroup_lruvec(struct mem_cgroup *memcg, struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *); +static inline bool lruvec_holds_page_lru_lock(struct page *page, + struct lruvec *lruvec) +{ + pg_data_t *pgdat = page_pgdat(page); + const struct mem_cgroup *memcg; + struct mem_cgroup_per_node *mz; + + if (mem_cgroup_disabled()) + return lruvec == &pgdat->__lruvec; + + mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); + memcg = page->mem_cgroup ? : root_mem_cgroup; + + return lruvec->pgdat == pgdat && mz->memcg == memcg; +} + struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); @@ -1221,6 +1237,14 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page, return &pgdat->__lruvec; } +static inline bool lruvec_holds_page_lru_lock(struct page *page, + struct lruvec *lruvec) +{ + pg_data_t *pgdat = page_pgdat(page); + + return lruvec == &pgdat->__lruvec; +} + static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg) { return NULL; @@ -1663,6 +1687,34 @@ static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec, spin_unlock_irqrestore(&lruvec->lru_lock, flags); } +/* Don't lock again iff page's lruvec locked */ +static inline struct lruvec *relock_page_lruvec_irq(struct page *page, + struct lruvec *locked_lruvec) +{ + if (locked_lruvec) { + if (lruvec_holds_page_lru_lock(page, locked_lruvec)) + return 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) +{ + if (locked_lruvec) { + if (lruvec_holds_page_lru_lock(page, locked_lruvec)) + return 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/mlock.c b/mm/mlock.c index ab164a675c25..55b3b3672977 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -277,16 +277,7 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone) * so we can spare the get_page() here. */ if (TestClearPageLRU(page)) { - struct lruvec *new_lruvec; - - new_lruvec = mem_cgroup_page_lruvec(page, - page_pgdat(page)); - if (new_lruvec != lruvec) { - if (lruvec) - unlock_page_lruvec_irq(lruvec); - lruvec = lock_page_lruvec_irq(page); - } - + lruvec = relock_page_lruvec_irq(page, lruvec); del_page_from_lru_list(page, lruvec, page_lru(page)); continue; diff --git a/mm/swap.c b/mm/swap.c index ed033f7c4f2d..c593ba596dea 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -210,19 +210,12 @@ static void pagevec_lru_move_fn(struct pagevec *pvec, for (i = 0; i < pagevec_count(pvec); i++) { struct page *page = pvec->pages[i]; - struct lruvec *new_lruvec; /* block memcg migration during page moving between lru */ if (!TestClearPageLRU(page)) continue; - new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - if (lruvec != new_lruvec) { - if (lruvec) - unlock_page_lruvec_irqrestore(lruvec, flags); - lruvec = lock_page_lruvec_irqsave(page, &flags); - } - + lruvec = relock_page_lruvec_irqsave(page, lruvec, &flags); (*move_fn)(page, lruvec); SetPageLRU(page); @@ -918,17 +911,12 @@ void release_pages(struct page **pages, int nr) } if (PageLRU(page)) { - struct lruvec *new_lruvec; - - new_lruvec = mem_cgroup_page_lruvec(page, - page_pgdat(page)); - if (new_lruvec != lruvec) { - if (lruvec) - unlock_page_lruvec_irqrestore(lruvec, - flags); + struct lruvec *prev_lruvec = lruvec; + + lruvec = relock_page_lruvec_irqsave(page, lruvec, + &flags); + if (prev_lruvec != lruvec) lock_batch = 0; - lruvec = lock_page_lruvec_irqsave(page, &flags); - } VM_BUG_ON_PAGE(!PageLRU(page), page); __ClearPageLRU(page); @@ -1033,15 +1021,8 @@ void __pagevec_lru_add(struct pagevec *pvec) for (i = 0; i < pagevec_count(pvec); i++) { struct page *page = pvec->pages[i]; - struct lruvec *new_lruvec; - - new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - if (lruvec != new_lruvec) { - if (lruvec) - unlock_page_lruvec_irqrestore(lruvec, flags); - lruvec = lock_page_lruvec_irqsave(page, &flags); - } + lruvec = relock_page_lruvec_irqsave(page, lruvec, &flags); __pagevec_lru_add_fn(page, lruvec); } if (lruvec) diff --git a/mm/vmscan.c b/mm/vmscan.c index 2953ddec88a0..3b09a39de8cd 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1884,8 +1884,7 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, * All pages were isolated from the same lruvec (and isolation * inhibits memcg migration). */ - VM_BUG_ON_PAGE(mem_cgroup_page_lruvec(page, page_pgdat(page)) - != lruvec, page); + VM_BUG_ON_PAGE(!lruvec_holds_page_lru_lock(page, lruvec), page); lru = page_lru(page); nr_pages = thp_nr_pages(page); @@ -4277,7 +4276,6 @@ void check_move_unevictable_pages(struct pagevec *pvec) for (i = 0; i < pvec->nr; i++) { struct page *page = pvec->pages[i]; int nr_pages; - struct lruvec *new_lruvec; if (PageTransTail(page)) continue; @@ -4289,13 +4287,7 @@ void check_move_unevictable_pages(struct pagevec *pvec) if (!TestClearPageLRU(page)) continue; - new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page)); - 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 (page_evictable(page) && PageUnevictable(page)) { enum lru_list lru = page_lru_base_type(page);