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=-16.7 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,URIBL_BLOCKED,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 9F958C4320A for ; Sat, 14 Aug 2021 05:26:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 879F261038 for ; Sat, 14 Aug 2021 05:26:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237257AbhHNF0v (ORCPT ); Sat, 14 Aug 2021 01:26:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42020 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236925AbhHNF0r (ORCPT ); Sat, 14 Aug 2021 01:26:47 -0400 Received: from mail-pl1-x62c.google.com (mail-pl1-x62c.google.com [IPv6:2607:f8b0:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7BACC061757 for ; Fri, 13 Aug 2021 22:26:19 -0700 (PDT) Received: by mail-pl1-x62c.google.com with SMTP id n12so14020679plf.4 for ; Fri, 13 Aug 2021 22:26:19 -0700 (PDT) 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=fPIEUgCv2CfVB3RBhBUqutTabZnAlwkc6TmF8u0la+M=; b=evzFsEQ5cP5VAHIL/eesP/y9sy4kvCZ9J4vPwMM2WZeM3i2WpFmYbgXqFhi7udyynW 1aMUdu+vZBYPWaxURBSa7XvTgGwbtY2Yti0mSH1AAERVh8UGsXqrKAKvcvMj2UnJJQ+a JXOPRC9/lmWRFRzm2zDJac+b32GcJJmKA64coKjcw4dkIOsFQL7IGMMaX7O1/Ay+jfqa to8CPnjiQh/hSZjI3V0a8RTln46tcbOf+p/S72IZunpbIOzatgr0PJFm0XxBXm11xIr8 osFk2afW32RSq/oNKn00qTjBLBWtlMZYo4XNh5NjDYGIbPRh/nkRSYmm+Moiv2c+QijM 7rVw== 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=fPIEUgCv2CfVB3RBhBUqutTabZnAlwkc6TmF8u0la+M=; b=Sx500uTlIaHhtW16w8nISSHQL+1ZtktF3voIVeo3dZnH3aOf61auAVZbOyE1pT+r7A XwVKkmJXN/x/lprr6pnd6nDA7t8OTvJrDWHxbIFwuO2iCU8gWKDNdC7sgJdWOoDmyj33 +os736mQ9kbqHU91pR/6OYx/dyyiLe8Q3Xv8sSVXzgf+8SmqGyGOpAGdmgwqyM3TRwnH 86ovnj/nFTLp79LZ2ePA0VgUMzPWbXoy5FwJq0YolSYHLt+R7toPKwiZMBoXH2MOAPJC PM/JOJArwpQYfoZ4GuiJAAbzr38xYqbutw3qm3u7em+xeLV139vYqGt7UT4y02mWSBzm DB7Q== X-Gm-Message-State: AOAM5301rjzoLPPVL2YhUzp02cFM2vTyNhBpZMbZLjLFI6Xw9n37D0Ne YEMXaZyGmF1wxMcUtjp7hcmBfQ== X-Google-Smtp-Source: ABdhPJzxwFjAn1im6gsgSEHt+LwD4iGMz1KIVynJ4deShVJLjmTgUF214h03/eIQOp5o9YqHY/X2sA== X-Received: by 2002:a17:90a:c087:: with SMTP id o7mr5996988pjs.57.1628918779474; Fri, 13 Aug 2021 22:26:19 -0700 (PDT) Received: from localhost.localdomain ([139.177.225.237]) by smtp.gmail.com with ESMTPSA id s5sm4783133pgp.81.2021.08.13.22.26.13 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Aug 2021 22:26:19 -0700 (PDT) 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, fam.zheng@bytedance.com, bsingharora@gmail.com, shy828301@gmail.com, alexs@kernel.org, smuchun@gmail.com, zhengqi.arch@bytedance.com, Muchun Song Subject: [PATCH v1 08/12] mm: memcontrol: introduce memcg_reparent_ops Date: Sat, 14 Aug 2021 13:25:15 +0800 Message-Id: <20210814052519.86679-9-songmuchun@bytedance.com> X-Mailer: git-send-email 2.21.0 (Apple Git-122) In-Reply-To: <20210814052519.86679-1-songmuchun@bytedance.com> References: <20210814052519.86679-1-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In the previous patch, we know how to make the lruvec lock safe when LRU pages are reparented. We should do something like following. memcg_reparent_objcgs(memcg) 1) lock // lruvec belongs to memcg and lruvec_parent belongs to parent memcg. spin_lock(&lruvec->lru_lock); spin_lock(&lruvec_parent->lru_lock); 2) do reparent // Move all the pages from the lruvec list to the parent lruvec list. 3) unlock spin_unlock(&lruvec_parent->lru_lock); spin_unlock(&lruvec->lru_lock); Apart from the page lruvec lock, the deferred split queue lock (THP only) also needs to do something similar. So we extract the necessary three steps in the memcg_reparent_objcgs(). memcg_reparent_objcgs(memcg) 1) lock memcg_reparent_ops->lock(memcg, parent); 2) reparent memcg_reparent_ops->reparent(memcg, reparent); 3) unlock memcg_reparent_ops->unlock(memcg, reparent); Now there are two different locks (e.g. lruvec lock and deferred split queue lock) need to use this infrastructure. In the next patch, we will use those APIs to make those locks safe when the LRU pages reparented. Signed-off-by: Muchun Song --- include/linux/memcontrol.h | 7 +++++++ mm/memcontrol.c | 43 +++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 48 insertions(+), 2 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 431fc606f6f9..d85c03f2d76d 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -352,6 +352,13 @@ struct mem_cgroup { struct mem_cgroup_per_node *nodeinfo[]; }; +struct memcg_reparent_ops { + /* Irq is disabled before calling those callbacks. */ + void (*lock)(struct mem_cgroup *memcg, struct mem_cgroup *parent); + void (*unlock)(struct mem_cgroup *memcg, struct mem_cgroup *parent); + void (*reparent)(struct mem_cgroup *memcg, struct mem_cgroup *parent); +}; + /* * size of first charge trial. "32" comes from vmscan.c's magic value. * TODO: maybe necessary to use big numbers in big irons. diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 0eca3cf6cede..8cfb4221c36a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -344,6 +344,35 @@ static struct obj_cgroup *obj_cgroup_alloc(void) return objcg; } +static const struct memcg_reparent_ops *memcg_reparent_ops[] = {}; + +static void memcg_reparent_lock(struct mem_cgroup *memcg, + struct mem_cgroup *parent) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(memcg_reparent_ops); i++) + memcg_reparent_ops[i]->lock(memcg, parent); +} + +static void memcg_reparent_unlock(struct mem_cgroup *memcg, + struct mem_cgroup *parent) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(memcg_reparent_ops); i++) + memcg_reparent_ops[i]->unlock(memcg, parent); +} + +static void memcg_do_reparent(struct mem_cgroup *memcg, + struct mem_cgroup *parent) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(memcg_reparent_ops); i++) + memcg_reparent_ops[i]->reparent(memcg, parent); +} + static void memcg_reparent_objcgs(struct mem_cgroup *memcg) { struct obj_cgroup *objcg, *iter; @@ -353,9 +382,13 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg) if (!parent) parent = root_mem_cgroup; + local_irq_disable(); + + memcg_reparent_lock(memcg, parent); + objcg = rcu_replace_pointer(memcg->objcg, NULL, true); - spin_lock_irq(&css_set_lock); + spin_lock(&css_set_lock); /* 1) Ready to reparent active objcg. */ list_add(&objcg->list, &memcg->objcg_list); @@ -365,7 +398,13 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg) /* 3) Move already reparented objcgs to the parent's list */ list_splice(&memcg->objcg_list, &parent->objcg_list); - spin_unlock_irq(&css_set_lock); + spin_unlock(&css_set_lock); + + memcg_do_reparent(memcg, parent); + + memcg_reparent_unlock(memcg, parent); + + local_irq_enable(); percpu_ref_kill(&objcg->refcnt); } -- 2.11.0