From patchwork Fri Sep 29 18:00:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roman Gushchin X-Patchwork-Id: 146862 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2a8e:b0:403:3b70:6f57 with SMTP id in14csp178184vqb; Fri, 29 Sep 2023 20:46:03 -0700 (PDT) X-Google-Smtp-Source: AGHT+IH++JWVY7XI/LW+rwFdlYOAgxRQ20225OIB92/FlAwyRaPZVLtyevVn6xAS4d66uaHgYy8V X-Received: by 2002:a05:6808:912:b0:3a8:472b:febf with SMTP id w18-20020a056808091200b003a8472bfebfmr6131181oih.21.1696045563601; Fri, 29 Sep 2023 20:46:03 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1696045563; cv=none; d=google.com; s=arc-20160816; b=xdog98zjh9w3BwfqqlZ1n50QDiNiTy+EOOJkl0jPyLrs0gGrBVZW2Tl0+hfN6oAYGr aid962D8HvOXYj8WFvJT0m5g3ClgtzKcauU65xCLSymUnXJoub670aWRqiTKqGtSHCCN LQgDJO6Z/K1ng77ZQs1kUeNx7ImsirSgEbr73PcY446/izidhMw5IUC4rxgXsGSV3D8h 8rRXFvrzvFT7YeRmJgycvMpLDvLlTbnOnM+YPD9kIfypG2PcTCtLEoo9QNeda0xVabvM JSurEgovETuWq6FmqosdBPdo3ldwkh/0L/j4rCe2gNUKxP9JQ2AWHZKvQeXxm2QQxCCn 6mow== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=i5Ua/wdmvBo/wu1nXQ0Cl5cuox9DFv/B5F3hb3WMJFo=; fh=GrOh8lyhpWnv6fQ7PEuyh7hTNeBQucAMexY2PVem5IM=; b=QADsiVokOMj0G4rbXpOVluW9xLgdw9IrJvYet4bZCt4n3Q4AtvMVxrPSiQ4wTgfQO8 8SYnCXeoiNWY7R3ilgJoQCHaVX/htl3GOmI9uK8uHwLYaJuRKr4orzemDuteaSZXlfjh CcCp9g5J8ikz0TB2v2FKDmk5SQAUnrpkwk855+9lIt1S6afD4QAiCwqAmWdOPcbPk3GG +a/mJEAaZAIDHhnQjw22AaI3FDg7vvxQgqCsApv6cBpIglXqgrKXERYkZ4SBuNPKSRbD 3OLQ3dmuKi3VEMtJRT7xdNGUuJ2ztq2H+fMiCvATBvPWWvLyINaNN7XCOsHY68Pps97o fWlQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=iy2KaghV; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: from howler.vger.email (howler.vger.email. [23.128.96.34]) by mx.google.com with ESMTPS id q18-20020a17090311d200b001b89551a392si23998519plh.113.2023.09.29.20.46.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 29 Sep 2023 20:46:03 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) client-ip=23.128.96.34; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.dev header.s=key1 header.b=iy2KaghV; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.dev Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id 0F04D822D577; Fri, 29 Sep 2023 11:01:48 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at howler.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233717AbjI2SB2 (ORCPT + 19 others); Fri, 29 Sep 2023 14:01:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49100 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233727AbjI2SBZ (ORCPT ); Fri, 29 Sep 2023 14:01:25 -0400 Received: from out-208.mta0.migadu.com (out-208.mta0.migadu.com [91.218.175.208]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 148321AE for ; Fri, 29 Sep 2023 11:01:22 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1696010477; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=i5Ua/wdmvBo/wu1nXQ0Cl5cuox9DFv/B5F3hb3WMJFo=; b=iy2KaghVwmRlwfpu6b7+AOhBWIOkmf5hD6kyAjLMK5XlcnnjDizfH24Jr/mHe5sgea67k7 4WiyJ8S09oEuEbj4kODKMMxIn9KtFUE1gjaYCUzSTGsq7ELsKoT6yLcMwvrxUsNOMZ4P39 APJaRZfIVaJdT9iKHDsVsLui/4J0bOY= From: Roman Gushchin To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Johannes Weiner , Michal Hocko , Shakeel Butt , Muchun Song , Dennis Zhou , Andrew Morton , David Rientjes , Vlastimil Babka , Roman Gushchin Subject: [PATCH v1 1/5] mm: kmem: optimize get_obj_cgroup_from_current() Date: Fri, 29 Sep 2023 11:00:51 -0700 Message-ID: <20230929180056.1122002-2-roman.gushchin@linux.dev> In-Reply-To: <20230929180056.1122002-1-roman.gushchin@linux.dev> References: <20230929180056.1122002-1-roman.gushchin@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (howler.vger.email [0.0.0.0]); Fri, 29 Sep 2023 11:01:48 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1778432672991931379 X-GMAIL-MSGID: 1778432672991931379 Manually inline memcg_kmem_bypass() and active_memcg() to speed up get_obj_cgroup_from_current() by avoiding duplicate in_task() checks and active_memcg() readings. Also add a likely() macro to __get_obj_cgroup_from_memcg(): obj_cgroup_tryget() should succeed at almost all times except a very unlikely race with the memcg deletion path. Signed-off-by: Roman Gushchin (Cruise) Acked-by: Shakeel Butt Acked-by: Johannes Weiner --- mm/memcontrol.c | 34 ++++++++++++++-------------------- 1 file changed, 14 insertions(+), 20 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9741d62d0424..16ac2a5838fb 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1068,19 +1068,6 @@ struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) } EXPORT_SYMBOL(get_mem_cgroup_from_mm); -static __always_inline bool memcg_kmem_bypass(void) -{ - /* Allow remote memcg charging from any context. */ - if (unlikely(active_memcg())) - return false; - - /* Memcg to charge can't be determined. */ - if (!in_task() || !current->mm || (current->flags & PF_KTHREAD)) - return true; - - return false; -} - /** * mem_cgroup_iter - iterate over memory cgroup hierarchy * @root: hierarchy root @@ -3007,7 +2994,7 @@ static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) for (; !mem_cgroup_is_root(memcg); memcg = parent_mem_cgroup(memcg)) { objcg = rcu_dereference(memcg->objcg); - if (objcg && obj_cgroup_tryget(objcg)) + if (likely(objcg && obj_cgroup_tryget(objcg))) break; objcg = NULL; } @@ -3016,16 +3003,23 @@ static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void) { - struct obj_cgroup *objcg = NULL; struct mem_cgroup *memcg; + struct obj_cgroup *objcg; - if (memcg_kmem_bypass()) - return NULL; + if (in_task()) { + memcg = current->active_memcg; + + /* Memcg to charge can't be determined. */ + if (likely(!memcg) && (!current->mm || (current->flags & PF_KTHREAD))) + return NULL; + } else { + memcg = this_cpu_read(int_active_memcg); + if (likely(!memcg)) + return NULL; + } rcu_read_lock(); - if (unlikely(active_memcg())) - memcg = active_memcg(); - else + if (!memcg) memcg = mem_cgroup_from_task(current); objcg = __get_obj_cgroup_from_memcg(memcg); rcu_read_unlock();