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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 5715BC433DB for ; Mon, 1 Mar 2021 06:27:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 07A2664E09 for ; Mon, 1 Mar 2021 06:27:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231960AbhCAG0f (ORCPT ); Mon, 1 Mar 2021 01:26:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231932AbhCAGZw (ORCPT ); Mon, 1 Mar 2021 01:25:52 -0500 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54339C06178C for ; Sun, 28 Feb 2021 22:24:47 -0800 (PST) Received: by mail-pl1-x62d.google.com with SMTP id z11so1519924plg.10 for ; Sun, 28 Feb 2021 22:24:47 -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:in-reply-to:references :mime-version:content-transfer-encoding; bh=o7QhLv5gQurpL6BkSCLndHABMXsANOfSdd3xoUJITvQ=; b=Yar2qzoSxku0EoB9WmsR/XSu1T9sO9Fx49sg1/60AwPq3qbgiP/Y8Ck4ZCrh4R6OXA KoZDdJzIOuO7ltFFb5kUO55IP9PwiOYtJ+QNaGTS1h7GkKdxO+01SNIzhVbNvIi/8loz sinz/+KSOoHEo03bdgot6IzvHDT///+t45el89jQmqGASFqmWSAo6netSHf9+g3SDwWY xHx4D99m4+YRf6zSAEYFB5A9ay2HO7ONkgea70W3E5xLJkikMgIJgq4cSS80xRGJvPh/ yOFpm7UI9g2P2XOF49h4yRPoNYA7oLRwBKLB+mCzEuDssMTYf8H1xy38Duov3x/OhCEJ iodg== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=o7QhLv5gQurpL6BkSCLndHABMXsANOfSdd3xoUJITvQ=; b=uJ+cOXnfowh3p9PqZZnBCEjbu6VIOZnkOKavl1d/al/RnDBVfR6qyjFsU/Iypk1WtA 6CpPH04vU4G2C/1DWtC0NMew8nYaqNtKSmbasfcExqTYkA0UhaOZCtUFnOmfwo6hTOcD U680OUiCX0EjSoUupkhDoffriYRTE63qVxKEl3t7mVPBiPYGBAQj6kCkl2tPp0Q+jvi7 mzwuZ57D7OKo60PI+j7NO7kGiOSrnjq5umDlypp9g0HCMPo2+EZlwFl+9mLB94cSn6q4 2sCKYO6rFp5a7QdOMrsV1dNBjwWWip/3GbI6Ww3LcpVlyVj5as7YiMm5OC9vlwnYgAGN 5sUw== X-Gm-Message-State: AOAM531FhA4P2HE3NqMecW9xYZwDtGmoAKqJQYlUDWoTncAn6O9AFIZu 9TTMiV8W4tZ+0sT3IAX8Sam/mg== X-Google-Smtp-Source: ABdhPJwG2x6S0WoOhSbLApU+6gZ68jAo9FncXvx14C+W9F4m8AqCqBOXVN9iwo2ZJyMz0HrV1Ek8wQ== X-Received: by 2002:a17:90a:8c84:: with SMTP id b4mr15827997pjo.21.1614579886895; Sun, 28 Feb 2021 22:24:46 -0800 (PST) Received: from localhost.localdomain ([139.177.225.227]) by smtp.gmail.com with ESMTPSA id x6sm14304626pfd.12.2021.02.28.22.24.28 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 28 Feb 2021 22:24:46 -0800 (PST) From: Muchun Song To: viro@zeniv.linux.org.uk, jack@suse.cz, amir73il@gmail.com, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com, akpm@linux-foundation.org, shakeelb@google.com, guro@fb.com, songmuchun@bytedance.com, alex.shi@linux.alibaba.com, alexander.h.duyck@linux.intel.com, chris@chrisdown.name, richard.weiyang@gmail.com, vbabka@suse.cz, mathieu.desnoyers@efficios.com, posk@google.com, jannh@google.com, iamjoonsoo.kim@lge.com, daniel.vetter@ffwll.ch, longman@redhat.com, walken@google.com, christian.brauner@ubuntu.com, ebiederm@xmission.com, keescook@chromium.org, krisman@collabora.com, esyr@redhat.com, surenb@google.com, elver@google.com Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, duanxiongchun@bytedance.com Subject: [PATCH 1/5] mm: memcontrol: introduce obj_cgroup_{un}charge_page Date: Mon, 1 Mar 2021 14:22:23 +0800 Message-Id: <20210301062227.59292-2-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20210301062227.59292-1-songmuchun@bytedance.com> References: <20210301062227.59292-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We know that the unit of charging slab object is bytes, the unit of charging kmem page is PAGE_SIZE. So If we want to reuse obj_cgroup APIs to charge the kmem pages, we should pass PAGE_SIZE (as third parameter) to obj_cgroup_charge(). Because the charing size is page size, we always need to refill objcg stock. This is pointless. As we already know the charing size. So we can directly skip touch the objcg stock and introduce obj_cgroup_{un}charge_page() to charge or uncharge a kmem page. In the later patch, we can reuse those helpers to charge/uncharge the kmem pages. This is just code movement without any functional change. Signed-off-by: Muchun Song --- mm/memcontrol.c | 46 +++++++++++++++++++++++++++++++--------------- 1 file changed, 31 insertions(+), 15 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2db2aeac8a9e..2eafbae504ac 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3060,6 +3060,34 @@ static void memcg_free_cache_id(int id) ida_simple_remove(&memcg_cache_ida, id); } +static inline void obj_cgroup_uncharge_page(struct obj_cgroup *objcg, + unsigned int nr_pages) +{ + rcu_read_lock(); + __memcg_kmem_uncharge(obj_cgroup_memcg(objcg), nr_pages); + rcu_read_unlock(); +} + +static int obj_cgroup_charge_page(struct obj_cgroup *objcg, gfp_t gfp, + unsigned int nr_pages) +{ + struct mem_cgroup *memcg; + int ret; + + rcu_read_lock(); +retry: + memcg = obj_cgroup_memcg(objcg); + if (unlikely(!css_tryget(&memcg->css))) + goto retry; + rcu_read_unlock(); + + ret = __memcg_kmem_charge(memcg, gfp, nr_pages); + + css_put(&memcg->css); + + return ret; +} + /** * __memcg_kmem_charge: charge a number of kernel pages to a memcg * @memcg: memory cgroup to charge @@ -3184,11 +3212,8 @@ static void drain_obj_stock(struct memcg_stock_pcp *stock) unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; unsigned int nr_bytes = stock->nr_bytes & (PAGE_SIZE - 1); - if (nr_pages) { - rcu_read_lock(); - __memcg_kmem_uncharge(obj_cgroup_memcg(old), nr_pages); - rcu_read_unlock(); - } + if (nr_pages) + obj_cgroup_uncharge_page(old, nr_pages); /* * The leftover is flushed to the centralized per-memcg value. @@ -3246,7 +3271,6 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) { - struct mem_cgroup *memcg; unsigned int nr_pages, nr_bytes; int ret; @@ -3263,24 +3287,16 @@ int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) * refill_obj_stock(), called from this function or * independently later. */ - rcu_read_lock(); -retry: - memcg = obj_cgroup_memcg(objcg); - if (unlikely(!css_tryget(&memcg->css))) - goto retry; - rcu_read_unlock(); - nr_pages = size >> PAGE_SHIFT; nr_bytes = size & (PAGE_SIZE - 1); if (nr_bytes) nr_pages += 1; - ret = __memcg_kmem_charge(memcg, gfp, nr_pages); + ret = obj_cgroup_charge_page(objcg, gfp, nr_pages); if (!ret && nr_bytes) refill_obj_stock(objcg, PAGE_SIZE - nr_bytes); - css_put(&memcg->css); return ret; } -- 2.11.0