From patchwork Mon Oct 30 13:12:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Uladzislau Rezki X-Patchwork-Id: 13440555 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9DA61C001B0 for ; Mon, 30 Oct 2023 13:13:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233318AbjJ3NNF (ORCPT ); Mon, 30 Oct 2023 09:13:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38106 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233298AbjJ3NND (ORCPT ); Mon, 30 Oct 2023 09:13:03 -0400 Received: from mail-lj1-x234.google.com (mail-lj1-x234.google.com [IPv6:2a00:1450:4864:20::234]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 400C5C2; Mon, 30 Oct 2023 06:13:01 -0700 (PDT) Received: by mail-lj1-x234.google.com with SMTP id 38308e7fff4ca-2c595f5dc84so61743431fa.0; Mon, 30 Oct 2023 06:13:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1698671579; x=1699276379; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=VxNONTjcbTR5IGf7JU34sfB7ky/8i9fS4GX+806ft28=; b=MM3j685o6j72EYnhokLAiokb2UgwhxyZ38xqmPUknazr26XvB3prqGKHPajD9GSKh9 PO4+QfXV/0Q176xkKR0tUVptlSM/XLIjedETd7LCrKJN0YqtsVCGwaDI16rA6kz/rUsY qx7caQcq+pSyxnT4t+Rr9sKb+WmQ5nxq392gCUgxc+XNzT8IxQoq1glxNdAX9htyhjRH N5sOZ3QQT6p7Iv0yqIwHWp2KOuyODnQv4ySZIKQCC3f1hc2mywYrS4RRomx6pLSvfvB6 3ZSR/bAyn2d/X6IqKESWpMz1Gd19+5UddwYwo3Fof6azrd1b1T1TBXTl9Uz+b1IaaKyN zt6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698671579; x=1699276379; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=VxNONTjcbTR5IGf7JU34sfB7ky/8i9fS4GX+806ft28=; b=nP9oVv26wN93wui5n3ewZcHLwo0NhDGo8AnsN52ADKo7Je07ts6zebujkiJAys73RM xci6/V1odl6DYKES2keOjrC7n0cwdmc7ny0XknRohAIyFFiWNhIh6n9SNa2K0Y1UOPPl 3OTnUM++ESEhfmg5hPxGeof2lld7AZL10PK98iAEy9a/8I/qCT5wxbr0Jj8NpdEwM6li AbcqHr5GFsTKwQSDaGMdg1C040YQ92DTy+SkfpagSYZUrILcBVh2J4GCSklscGd6eTzl vRw4msg8peue9ubPFbrGkgFwmPx7RGymi7UcXf7I5EQEjYdTxFHkDKD6Y8wdRUzBlz4m ODHQ== X-Gm-Message-State: AOJu0Yx1eou0ubCt+IxckJrGN+9GA8F+uCmJs7SLO4lskps9ja38Eoi1 geTTieNw6po/LKtq+xgPj3w= X-Google-Smtp-Source: AGHT+IGZIU3+zcqRFcycB/zEZR9+2Pt8egGj4lqIF5eegoShcZC5Ho+G2EIZrrc7iIn7RimDSj+zDg== X-Received: by 2002:a05:6512:ea5:b0:501:ba04:f352 with SMTP id bi37-20020a0565120ea500b00501ba04f352mr4713662lfb.1.1698671579336; Mon, 30 Oct 2023 06:12:59 -0700 (PDT) Received: from pc638.lan ([155.137.26.201]) by smtp.gmail.com with ESMTPSA id q11-20020ac2510b000000b005079691360csm1431887lfb.49.2023.10.30.06.12.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Oct 2023 06:12:58 -0700 (PDT) From: "Uladzislau Rezki (Sony)" To: "Paul E . McKenney" Cc: RCU , Neeraj upadhyay , Boqun Feng , Hillf Danton , Joel Fernandes , LKML , Uladzislau Rezki , Oleksiy Avramchenko , Frederic Weisbecker Subject: [PATCH v2 3/3] doc: Add rcutree.rcu_normal_wake_from_gp to kernel-parameters.txt Date: Mon, 30 Oct 2023 14:12:54 +0100 Message-Id: <20231030131254.488186-4-urezki@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20231030131254.488186-1-urezki@gmail.com> References: <20231030131254.488186-1-urezki@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org This commit adds rcutree.rcu_normal_wake_from_gp description to the kernel-parameters.txt file. Signed-off-by: Uladzislau Rezki (Sony) --- Documentation/admin-guide/kernel-parameters.txt | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 03a4bdb7512b..a9681d2492d3 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5009,6 +5009,20 @@ this kernel boot parameter, forcibly setting it to zero. + rcutree.rcu_normal_wake_from_gp= [KNL] + Reduces a latency of synchronize_rcu() call. This approach + maintains its own track of synchronize_rcu() callers, so it + does not interact with regular callbacks because it does not + use a call_rcu[_hurry]() path. Please note, this is for a + normal grace period. + + How to enable it: + + echo 1 > /sys/module/rcutree/parameters/rcu_normal_wake_from_gp + or pass a boot parameter "rcutree.rcu_normal_wake_from_gp=1" + + Default is 0. + rcuscale.gp_async= [KNL] Measure performance of asynchronous grace-period primitives such as call_rcu().