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=-11.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 C803FC433E0 for ; Wed, 3 Mar 2021 12:56:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 97EB464E58 for ; Wed, 3 Mar 2021 12:56:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232728AbhCCL7g (ORCPT ); Wed, 3 Mar 2021 06:59:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1451332AbhCCGCg (ORCPT ); Wed, 3 Mar 2021 01:02:36 -0500 Received: from mail-pg1-x529.google.com (mail-pg1-x529.google.com [IPv6:2607:f8b0:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 419E6C061756 for ; Tue, 2 Mar 2021 22:01:56 -0800 (PST) Received: by mail-pg1-x529.google.com with SMTP id g4so15577359pgj.0 for ; Tue, 02 Mar 2021 22:01:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=w7StTxcyXcafl4uEbG/aIE82ifm7bKYtlIbdebIFMPE=; b=ugTE4jP9VW9bZE+/2dIrXgQ3ommzWl3Nxt2OliKGmVfndlY8ZaqWwe3VdgUozFbtbO JLK+h1YW00HCqURjk55+KtMDyzm+naagIlF02qDulyra+eoNWMnNxNIUUgkJDkIMbJ6K cHpg+9UTHAUDsVRZZwGgRbYFCtk3r6vNHy1ml8OTz/JW68UeHkFORFSWLc41tsIwoMxz 4BXIdQA8/wdwwmqUrLaqu0Px3XNEw+BwGzfQGQXRm8OdpIuQawHq5M4iK7zXvjleGBHW XQ7+2OP6j6JMfldjPRA48T5uz0iGKCOA+TdRoLYrNXkL1z0iJeqQpq0aqqSFVC4Rq0YD bZcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=w7StTxcyXcafl4uEbG/aIE82ifm7bKYtlIbdebIFMPE=; b=m1Ebk5uyABaxS31vBdqYPZKOmjZCw2vjwxnEHKvSHYsc41l1q0itvCmV9DXTzIbrif vi0Gm9LkZE+KGG3smoWgS/l+s6RJapY8qKutJipKb3Ps+3vBR3RV0r8EPy+R+/NMWSB7 4PERy7DA/emP1xoEGLy/6FbPtafkKr/zVWd+fa57a980fxTkRHkV+lGXD8Rwq97OzcKT X484IpvHclaB6CHgw4wnHP8qmQykycG5qTDwd7Gnsc0aYh6jAoyQ/la5Y5tGIWio5w3t GtSlAxub9YJL2BDkzripHh/lDvh9G2n9i/0vczfI7WdU1T4n3hY7eJd20rrToAuuMJAe Y/Dg== X-Gm-Message-State: AOAM530S4hQoaKcyx6IViETue9KxCI4Ptk33Gty/O0NGQYw77OuPxZlX AO7Cs1fzJCB1AMLx4GPsVj2Jig== X-Google-Smtp-Source: ABdhPJwp+JatXF/+aMDFUZxyOjFQpcFSO9nkpqnoJ3n4zsSHtLSG3bwWOPuE6m9zfrTO6FBdTkjrVA== X-Received: by 2002:a63:1843:: with SMTP id 3mr21857213pgy.253.1614751315725; Tue, 02 Mar 2021 22:01:55 -0800 (PST) Received: from localhost.localdomain ([139.177.225.227]) by smtp.gmail.com with ESMTPSA id x11sm6131088pjh.0.2021.03.02.22.01.51 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 02 Mar 2021 22:01:55 -0800 (PST) From: Muchun Song To: guro@fb.com, hannes@cmpxchg.org, mhocko@kernel.org, akpm@linux-foundation.org, shakeelb@google.com, vdavydov.dev@gmail.com Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com, Muchun Song Subject: [PATCH v2 0/5] Use obj_cgroup APIs to charge kmem pages Date: Wed, 3 Mar 2021 13:59:12 +0800 Message-Id: <20210303055917.66054-1-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since Roman series "The new cgroup slab memory controller" applied. All slab objects are charged with the new APIs of obj_cgroup. The new APIs introduce a struct obj_cgroup to charge slab objects. It prevents long-living objects from pinning the original memory cgroup in the memory. But there are still some corner objects (e.g. allocations larger than order-1 page on SLUB) which are not charged with the new APIs. Those objects (include the pages which are allocated from buddy allocator directly) are charged as kmem pages which still hold a reference to the memory cgroup. E.g. We know that the kernel stack is charged as kmem pages because the size of the kernel stack can be greater than 2 pages (e.g. 16KB on x86_64 or arm64). If we create a thread (suppose the thread stack is charged to memory cgroup A) and then move it from memory cgroup A to memory cgroup B. Because the kernel stack of the thread hold a reference to the memory cgroup A. The thread can pin the memory cgroup A in the memory even if we remove the cgroup A. If we want to see this scenario by using the following script. We can see that the system has added 500 dying cgroups (This is not a real world issue, just a script to show that the large kmallocs are charged as kmem pages which can pin the memory cgroup in the memory). #!/bin/bash cat /proc/cgroups | grep memory cd /sys/fs/cgroup/memory echo 1 > memory.move_charge_at_immigrate for i in range{1..500} do mkdir kmem_test echo $$ > kmem_test/cgroup.procs sleep 3600 & echo $$ > cgroup.procs echo `cat kmem_test/cgroup.procs` > cgroup.procs rmdir kmem_test done cat /proc/cgroups | grep memory This patchset aims to make those kmem pages to drop the reference to memory cgroup by using the APIs of obj_cgroup. Finally, we can see that the number of the dying cgroups will not increase if we run the above test script. Patch 1-3 use obj_cgroup APIs to charge kmem pages. Patch 4 introduces remote objcg charging APIs. Patch 5 uses remote objcg charging APIs to charge kernel memory. Changlogs in v2: 1. Fix some types in the commit log (Thanks Roman). 2. Do not introduce page_memcg_kmem helper (Thanks to Johannes and Shakeel). 3. Reduce the CC list to mm/memcg folks (Thanks to Johannes). 4. Introduce remote objcg charging APIs instead of convert "remote memcg charging APIs" to "remote objcg charging APIs". Muchun Song (5): mm: memcontrol: introduce obj_cgroup_{un}charge_page mm: memcontrol: make page_memcg{_rcu} only applicable for non-kmem page mm: memcontrol: charge kmem pages by using obj_cgroup APIs mm: memcontrol: introduce remote objcg charging API mm: memcontrol: use remote objcg charging APIs to charge kernel memory fs/buffer.c | 10 +- fs/notify/fanotify/fanotify.c | 6 +- fs/notify/fanotify/fanotify_user.c | 2 +- fs/notify/group.c | 3 +- fs/notify/inotify/inotify_fsnotify.c | 8 +- fs/notify/inotify/inotify_user.c | 2 +- include/linux/bpf.h | 2 +- include/linux/fsnotify_backend.h | 2 +- include/linux/memcontrol.h | 114 +++++++++++++--- include/linux/sched.h | 4 + include/linux/sched/mm.h | 38 ++++++ kernel/bpf/syscall.c | 35 ++--- kernel/fork.c | 3 + mm/memcontrol.c | 257 ++++++++++++++++++++++++++--------- mm/page_alloc.c | 4 +- 15 files changed, 372 insertions(+), 118 deletions(-) -- 2.11.0