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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 5F41AC43387 for ; Wed, 9 Jan 2019 12:20:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3743520665 for ; Wed, 9 Jan 2019 12:20:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730829AbfAIMUw (ORCPT ); Wed, 9 Jan 2019 07:20:52 -0500 Received: from relay.sw.ru ([185.231.240.75]:42310 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729911AbfAIMUh (ORCPT ); Wed, 9 Jan 2019 07:20:37 -0500 Received: from [172.16.25.169] (helo=localhost.localdomain) by relay.sw.ru with esmtp (Exim 4.91) (envelope-from ) id 1ghCqU-0004h4-FM; Wed, 09 Jan 2019 15:20:30 +0300 Subject: [PATCH 2/3] mm: Recharge page memcg on first get from pagecache From: Kirill Tkhai To: akpm@linux-foundation.org, hannes@cmpxchg.org, josef@toxicpanda.com, jack@suse.cz, hughd@google.com, ktkhai@virtuozzo.com, darrick.wong@oracle.com, mhocko@suse.com, aryabinin@virtuozzo.com, guro@fb.com, mgorman@techsingularity.net, shakeelb@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Wed, 09 Jan 2019 15:20:30 +0300 Message-ID: <154703642996.32690.7131436841852687919.stgit@localhost.localdomain> In-Reply-To: <154703479840.32690.6504699919905946726.stgit@localhost.localdomain> References: <154703479840.32690.6504699919905946726.stgit@localhost.localdomain> User-Agent: StGit/0.18 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch makes pagecache_get_page() to charge uncharged page into memcg of process, which accesses the page first. Page will be returned in case of it's charged only, so memcg tasks can't use pages, which was left by __remove_mapping(), without accounting them. In case of accounting is not possible, pages remain in pagecache, and further global reclaim will remove them (and this will be easily, since pages are not mapped by any task). Also, note that uncharged page can't be dirty or under writeback, since it was able to be isolated in __remove_mapping() earlier. Signed-off-by: Kirill Tkhai --- mm/filemap.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/mm/filemap.c b/mm/filemap.c index 65c85c47bdb1..2603c44fc74a 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1576,15 +1576,18 @@ EXPORT_SYMBOL(find_lock_entry); struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset, int fgp_flags, gfp_t gfp_mask) { + struct mem_cgroup *memcg; struct page *page; + bool drop_lock; repeat: + drop_lock = false; page = find_get_entry(mapping, offset); if (xa_is_value(page)) page = NULL; if (!page) goto no_page; - +lock: if (fgp_flags & FGP_LOCK) { if (fgp_flags & FGP_NOWAIT) { if (!trylock_page(page)) { @@ -1604,6 +1607,31 @@ struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset, VM_BUG_ON_PAGE(page->index != offset, page); } + if (!mem_cgroup_disabled() && !PageHuge(page) && + !page_memcg(page) && !page_mapped(page) && + test_bit(AS_KEEP_MEMCG_RECLAIM, &mapping->flags)) { + if (!(fgp_flags & FGP_LOCK)) { + drop_lock = true; + fgp_flags |= FGP_LOCK; + goto lock; + } + + if (!WARN_ON(PageDirty(page) || PageWriteback(page))) { + if (mem_cgroup_try_charge(page, current->mm, + gfp_mask, &memcg, false)) { + unlock_page(page); + put_page(page); + return NULL; + } + mem_cgroup_commit_charge(page, memcg, true, false); + if (!isolate_lru_page(page)) + putback_lru_page(page); + } + } + + if (drop_lock) + unlock_page(page); + if (fgp_flags & FGP_ACCESSED) mark_page_accessed(page);