From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6559C433E0 for ; Thu, 11 Jun 2020 06:18:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A6AE22075F for ; Thu, 11 Jun 2020 06:18:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726886AbgFKGSA (ORCPT ); Thu, 11 Jun 2020 02:18:00 -0400 Received: from out30-45.freemail.mail.aliyun.com ([115.124.30.45]:42562 "EHLO out30-45.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726577AbgFKGRM (ORCPT ); Thu, 11 Jun 2020 02:17:12 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R531e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01422;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=18;SR=0;TI=SMTPD_---0U.EpUdO_1591856227; Received: from localhost(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U.EpUdO_1591856227) by smtp.aliyun-inc.com(127.0.0.1); Thu, 11 Jun 2020 14:17:08 +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, yang.shi@linux.alibaba.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 Cc: "Kirill A. Shutemov" , Andrea Arcangeli Subject: [PATCH v12 07/16] mm/thp: narrow lru locking Date: Thu, 11 Jun 2020 14:16:40 +0800 Message-Id: <1591856209-166869-8-git-send-email-alex.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1591856209-166869-1-git-send-email-alex.shi@linux.alibaba.com> References: <1591856209-166869-1-git-send-email-alex.shi@linux.alibaba.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org lru_lock and page cache xa_lock have no reason with current sequence, put them together isn't necessary. let's narrow the lru locking, but left the local_irq_disable/preempt_disable to block interrupt re-entry and statistic update. Signed-off-by: Alex Shi Signed-off-by: Wei Yang Cc: Kirill A. Shutemov Cc: Andrea Arcangeli Cc: Johannes Weiner Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- mm/huge_memory.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 1cd81a9a4f80..4137f7f7d87e 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2442,8 +2442,6 @@ static void __split_huge_page(struct page *page, struct list_head *list, unsigned long offset = 0; int i; - lruvec = mem_cgroup_page_lruvec(head, pgdat); - /* complete memcg works before add pages to LRU */ mem_cgroup_split_huge_fixup(head); @@ -2455,6 +2453,11 @@ static void __split_huge_page(struct page *page, struct list_head *list, xa_lock(&swap_cache->i_pages); } + /* lock lru list/PageCompound, isolate freezed by page_ref_freeze */ + spin_lock(&pgdat->lru_lock); + + lruvec = mem_cgroup_page_lruvec(head, pgdat); + for (i = HPAGE_PMD_NR - 1; i >= 1; i--) { __split_huge_page_tail(head, i, lruvec, list); /* Some pages can be beyond i_size: drop them from page cache */ @@ -2472,8 +2475,8 @@ static void __split_huge_page(struct page *page, struct list_head *list, head + i, 0); } } - ClearPageCompound(head); + spin_unlock(&pgdat->lru_lock); split_page_owner(head, HPAGE_PMD_ORDER); @@ -2491,8 +2494,8 @@ static void __split_huge_page(struct page *page, struct list_head *list, page_ref_add(head, 2); xa_unlock(&head->mapping->i_pages); } - - spin_unlock_irqrestore(&pgdat->lru_lock, flags); + preempt_enable(); + local_irq_restore(flags); remap_page(head); @@ -2631,7 +2634,6 @@ bool can_split_huge_page(struct page *page, int *pextra_pins) int split_huge_page_to_list(struct page *page, struct list_head *list) { struct page *head = compound_head(page); - struct pglist_data *pgdata = NODE_DATA(page_to_nid(head)); struct deferred_split *ds_queue = get_deferred_split_queue(head); struct anon_vma *anon_vma = NULL; struct address_space *mapping = NULL; @@ -2697,9 +2699,8 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) unmap_page(head); VM_BUG_ON_PAGE(compound_mapcount(head), head); - /* prevent PageLRU to go away from under us, and freeze lru stats */ - spin_lock_irqsave(&pgdata->lru_lock, flags); - + local_irq_save(flags); + preempt_disable(); if (mapping) { XA_STATE(xas, &mapping->i_pages, page_index(head)); @@ -2748,7 +2749,8 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) spin_unlock(&ds_queue->split_queue_lock); fail: if (mapping) xa_unlock(&mapping->i_pages); - spin_unlock_irqrestore(&pgdata->lru_lock, flags); + preempt_enable(); + local_irq_restore(flags); remap_page(head); ret = -EBUSY; } -- 1.8.3.1