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[23.128.96.31]) by mx.google.com with ESMTPS id f9-20020a056a001ac900b006cdfce495b7si106566pfv.268.2023.11.30.12.44.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Nov 2023 12:44:04 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.31 as permitted sender) client-ip=23.128.96.31; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=MURdM+rt; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.31 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by morse.vger.email (Postfix) with ESMTP id D0A2082E297A; Thu, 30 Nov 2023 12:44:00 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at morse.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230006AbjK3Unn (ORCPT + 99 others); Thu, 30 Nov 2023 15:43:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56362 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232306AbjK3Unk (ORCPT ); Thu, 30 Nov 2023 15:43:40 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1268FD40 for ; Thu, 30 Nov 2023 12:43:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701377026; 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; bh=8uUhkmFY3baFHZKA0GPbNGpyZmiXUmHvRAktUmbwJUI=; b=MURdM+rtQK0ICYoELfWy4Z9LcDVgCeAQZvmxqJibUZSc6yRhXKvJ249n8xjtRIqJhoIuz2 0jfUpJ8SqkxQDpsJNB8tNV8GRpAHE0teZdyi3nK58HWnByZHYSn9P8u9TWtw0CROaOcTJ8 eEUIAxj/U4EFZlxifmgxXcvZm53nSFM= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-74-hNwsiTMiMOu0QY_LOCCSfg-1; Thu, 30 Nov 2023 15:43:44 -0500 X-MC-Unique: hNwsiTMiMOu0QY_LOCCSfg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 843A01C06ED1; Thu, 30 Nov 2023 20:43:43 +0000 (UTC) Received: from llong.com (unknown [10.22.9.192]) by smtp.corp.redhat.com (Postfix) with ESMTP id E72D340C6EB9; Thu, 30 Nov 2023 20:43:42 +0000 (UTC) From: Waiman Long To: Tejun Heo , Zefan Li , Johannes Weiner Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Joe Mario , Sebastian Jug , Yosry Ahmed , Waiman Long Subject: [PATCH-cgroup v5 0/2] cgroup/rstat: Further reduce cpu_lock hold time in cgroup_rstat_flush_locked Date: Thu, 30 Nov 2023 15:43:25 -0500 Message-Id: <20231130204327.494249-1-longman@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 X-Spam-Status: No, score=-0.9 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on morse.vger.email 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 (morse.vger.email [0.0.0.0]); Thu, 30 Nov 2023 12:44:00 -0800 (PST) v5: - Drop patch "cgroup/rstat: Reduce cpu_lock hold time in cgroup_rstat_flush_locked()" as it has been merged into the for-6.8 branch. - Rework the recursive cgroup_rstat_push_children() into an iterative function to prevent possibility of stack overflow. v4: - Update patch 2 to fix a minor bug and update some of the comments. v3: - Minor comment twisting as suggested by Yosry. - Add patches 2 and 3 to further reduce lock hold time The purpose of this patch series is to further reduce the cpu_lock hold time of cgroup_rstat_flush_locked() so as to reduce the latency impact when cgroup_rstat_updated() is called as they may contend with each other on the cpu_lock. Waiman Long (2): cgroup/rstat: Optimize cgroup_rstat_updated_list() cgroup: Avoid false cacheline sharing of read mostly rstat_cpu include/linux/cgroup-defs.h | 7 ++ kernel/cgroup/rstat.c | 153 +++++++++++++++++++++--------------- 2 files changed, 98 insertions(+), 62 deletions(-) -- 2.39.3