From patchwork Mon Oct 30 13:12:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Uladzislau Rezki X-Patchwork-Id: 159733 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:d641:0:b0:403:3b70:6f57 with SMTP id cy1csp2201633vqb; Mon, 30 Oct 2023 06:13:31 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFCadR4AzWdKUgMCON76FvgH1rH0xuOmNB51zXyihekoM+3bu7cPSSXskbitJ9Drbab7+yO X-Received: by 2002:a17:90b:4acb:b0:280:3650:382a with SMTP id mh11-20020a17090b4acb00b002803650382amr2507946pjb.16.1698671611416; Mon, 30 Oct 2023 06:13:31 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1698671611; cv=none; d=google.com; s=arc-20160816; b=Tv6fAcd1JV2w5rdaMpctx8j1ePCPYylzdltvh51/HmsGZVBIqxzDT8fmQP+AQyj4ki f4nD0DI8HjwB/imSZE2jgb8XmGBU9WrA3kwgXSK1ku3jXd8OEmSjgLZ+l4998SuKzVB1 Zpvlrz7XHU2wyb0W7tv64NNk9lgNDxOVrtLd70e6PA74wUgFvg5JgUN7gbC2Z7kjksB1 N41l5TMQCZsjakbWh32ZUyJnKjZc0EZ1ZMHJZasozIfU8nFNluXHFAGivoonzH1XEUT1 ytCe+rgPbTeh1qHc25AFVEX/ys1dXWFTCaiwDFQxAe2ER6CtmjCJoG5ktzGAlL5Shqf6 2n7w== 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=WLQIP7HJ05XUR3kXWK/jPVaD6NokUBVQvcd3TzedbeE=; fh=4iZcRCmzpaCZKgp7nvxh/m3AX3kfm//yPbGO/jIXleI=; b=f64LYNtDN6xEKM5/Emr2KvIWwO+tp+dr2VDkSK5oKiq04of+RFJgd/LM77GqcobqPf iDfCqqDPHWsXSNzlQJVhuk8MknCsdJ5K7EYeVDSZz8rz2NinveTNY7FSLzwc/E4e/qeT 8NUPShSFqKCH7U6x1Pxjzgn9Eo6/ziSRrCbTq+DM1Ca3RLp+Fox2TI0B766931Kfm3mI s6msfrzT0nHTCVQwDxVyD1Pay0IPuwwGz0sjCKVmuocTkZNj6iZfa/eEnNL6RrvSzsdN ek4yqzC0fjk4fM153GD22tPZ7ullx1VZ6iRUIlo5U8jQjWw6DCMuKWSN+DuK2o7fOk/D tCOw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=VnlS8V8P; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.38 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from fry.vger.email (fry.vger.email. [23.128.96.38]) by mx.google.com with ESMTPS id b15-20020a17090a6e0f00b002736ff3cc79si6807483pjk.23.2023.10.30.06.13.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Oct 2023 06:13:31 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.38 as permitted sender) client-ip=23.128.96.38; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=VnlS8V8P; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.38 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by fry.vger.email (Postfix) with ESMTP id 261C9805C3CA; Mon, 30 Oct 2023 06:13:29 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at fry.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233336AbjJ3NNG (ORCPT + 31 others); Mon, 30 Oct 2023 09:13:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233302AbjJ3NND (ORCPT ); Mon, 30 Oct 2023 09:13:03 -0400 Received: from mail-lj1-x235.google.com (mail-lj1-x235.google.com [IPv6:2a00:1450:4864:20::235]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D024C6; Mon, 30 Oct 2023 06:13:00 -0700 (PDT) Received: by mail-lj1-x235.google.com with SMTP id 38308e7fff4ca-2c5210a1515so64618441fa.0; Mon, 30 Oct 2023 06:13:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1698671578; x=1699276378; 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=WLQIP7HJ05XUR3kXWK/jPVaD6NokUBVQvcd3TzedbeE=; b=VnlS8V8P4dWlbRDbL6/s/z7T1WFSmIJIm7pCQMvXrpU1wwyON1FNEpU7aQ/KRORKX7 8XeMj6Wb8/Uy+9BSaJr1SqZBzAe06gbVhGkc7GEWnfL1twhtSxnqTkdUQiocTZQ51JLm NF76LfNmLfntTVSB+K+u2fE2eE8bUxfnjSdn2uOSMtu23Q4iVPQIboz5JgurYfBzMZ7j +lRHi3BU8dfbCNyjJMEPXJ8AwCgTW/iSukTN81JEUCTe0cbizMln5ZLoGCA30w+1cwC9 GBKUpBsK3MglhUKNLm96d+Nala9uvQ5a8kjWVCCXEa8XN3JWTetvvA0+BRxATjNukdp+ zmTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698671578; x=1699276378; 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=WLQIP7HJ05XUR3kXWK/jPVaD6NokUBVQvcd3TzedbeE=; b=wwDiXHV/Q++LkvEQcntyl7NrE/kChS6olJaNt2gOSlS3tEfLk+WfV+iOgSYCFfcOsd j1hjYxvDPr6zd0PE8Flfc7w/QJbty72j40Qh9HeTEhvXwNa3zEuo1QtwR5rKJnzXhv8i r/e4z/nw8rbbnzgMZE30+GEDoalPdyAphXLBx2WtsUWOQkA4n6dTsa8WLnjGDGBEkW34 gncUvmxw2WYmzsUE5+Y/E5Sj5PJo4dia99C7+EWyRf4v2+szd0tRk5QrnuG4jDTtKc4A Tjb7GpZeZiJmKmM7WL+E/NcBGz2Fsyc2v9JY8rucg7vpalktHBJ4kL6NXVxdI6amuNKy xHfw== X-Gm-Message-State: AOJu0YwDB1FQ/ZspBpHunNs7DdaUxH9fB9lBXPCj9JCEWQf15mnWJTIw cAYhPtQU4xTdaMd9a/tDclY= X-Received: by 2002:ac2:5def:0:b0:500:daec:2817 with SMTP id z15-20020ac25def000000b00500daec2817mr6956916lfq.54.1698671578431; Mon, 30 Oct 2023 06:12:58 -0700 (PDT) Received: from pc638.lan ([155.137.26.201]) by smtp.gmail.com with ESMTPSA id q11-20020ac2510b000000b005079691360csm1431887lfb.49.2023.10.30.06.12.57 (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 2/3] rcu: Add a trace event for synchronize_rcu_normal() Date: Mon, 30 Oct 2023 14:12:53 +0100 Message-Id: <20231030131254.488186-3-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 X-Spam-Status: No, score=-0.6 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 fry.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 (fry.vger.email [0.0.0.0]); Mon, 30 Oct 2023 06:13:29 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1781186283998993678 X-GMAIL-MSGID: 1781186283998993678 Add an rcu_sr_normal() trace event. It takes three arguments first one is the name of RCU flavour, second one is a user id which triggeres synchronize_rcu_normal() and last one is an event. There are two traces in the synchronize_rcu_normal(). On entry, when a new request is registered and on exit point when request is completed. Please note, CONFIG_RCU_TRACE=y is required to activate traces. Signed-off-by: Uladzislau Rezki (Sony) --- include/trace/events/rcu.h | 27 +++++++++++++++++++++++++++ kernel/rcu/tree.c | 2 ++ 2 files changed, 29 insertions(+) diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index 2ef9c719772a..31b3e0d3e65f 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -707,6 +707,33 @@ TRACE_EVENT_RCU(rcu_invoke_kfree_bulk_callback, __entry->rcuname, __entry->p, __entry->nr_records) ); +/* + * Tracepoint for a normal synchronize_rcu() states. The first argument + * is the RCU flavor, the second argument is a pointer to rcu_head the + * last one is an event. + */ +TRACE_EVENT_RCU(rcu_sr_normal, + + TP_PROTO(const char *rcuname, struct rcu_head *rhp, const char *srevent), + + TP_ARGS(rcuname, rhp, srevent), + + TP_STRUCT__entry( + __field(const char *, rcuname) + __field(void *, rhp) + __field(const char *, srevent) + ), + + TP_fast_assign( + __entry->rcuname = rcuname; + __entry->rhp = rhp; + __entry->srevent = srevent; + ), + + TP_printk("%s rhp=0x%p event=%s", + __entry->rcuname, __entry->rhp, __entry->srevent) +); + /* * Tracepoint for exiting rcu_do_batch after RCU callbacks have been * invoked. The first argument is the name of the RCU flavor, diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f04846b543de..189975f57e78 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3630,6 +3630,7 @@ static void synchronize_rcu_normal(void) { struct rcu_synchronize rs; + trace_rcu_sr_normal(rcu_state.name, &rs.head, TPS("request")); if (READ_ONCE(rcu_normal_wake_from_gp)) { init_rcu_head_on_stack(&rs.head); init_completion(&rs.completion); @@ -3650,6 +3651,7 @@ static void synchronize_rcu_normal(void) } else { wait_rcu_gp(call_rcu_hurry); } + trace_rcu_sr_normal(rcu_state.name, &rs.head, TPS("complete")); } /** 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: 159748 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:d641:0:b0:403:3b70:6f57 with SMTP id cy1csp2221853vqb; Mon, 30 Oct 2023 06:42:11 -0700 (PDT) X-Google-Smtp-Source: AGHT+IH+Pxo0GWGE+S9KuWNS6ithZVHXh/IGRCvgpK4Q/6aHiqFBD0EERP+2jYqBWHeJ6Nsbg/Cp X-Received: by 2002:a17:902:6acb:b0:1c6:a0b:7b9a with SMTP id i11-20020a1709026acb00b001c60a0b7b9amr9344410plt.3.1698673331489; Mon, 30 Oct 2023 06:42:11 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1698673331; cv=none; d=google.com; s=arc-20160816; b=xUzCMxVW08CoOStI2Yjlo77JoA+wjGK6wAzD3wPkDuji9OphlHCBQdQqdhwT1eTkEQ uB1YjDnfgom7edKhJ2zEgfHH6kpZTptnPBHPlW8Y9hCcI8I/dJsqZLh6wKEH4+Sq4Nx8 uHsPPLx1KeJLovGayd/dt0ipT6J7+ZgT/yXed0wnrFv7nKSbUaLDNzm1LLuaZrNlOPtV AnKkSljQpFwpTVRwtwxSKnpcHzx2J+xXtzSBcYhAq5yPpHbKkE+BNTWprpOzQyaxXUHX /phVoTqpc2ntrJl54/ljLIGvBoDZqR8FHH2k6KqhyRbL8CikSaPyhUBl5MkMVJqIwfQi Vkwg== 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=VxNONTjcbTR5IGf7JU34sfB7ky/8i9fS4GX+806ft28=; fh=4iZcRCmzpaCZKgp7nvxh/m3AX3kfm//yPbGO/jIXleI=; b=qAy4S3FyjUAMedHOUEESo55h4e7mXUcgpEeQDi1tDscUogkhtyT6RKmf12xPurvx45 sj0GJ3i2lU3Mh/sMxOvkdjFF6DwOoVmhsjkWeTtgev/7TWGI3rY0Mti29WuAFgCSwOVZ FQnVJETpP4wUa0+NyRvQWe9v2Dk0tpDfGZtUPgN9FVnE3k9UeorJ+ds8VEXOdt6n5RdY kt6eARNTEkCZY8cAIbTK/oVRX2ozkcnt8XY3HpI1QVX8/ro6rwLKXstMVEnnXkscbDmt yf3C8C27HiHmIYiN7BdCfvbpOnipwTbx/r1d0i2vi3I6M8uaKTiZJ5BbrwYYJfJ609L3 zNtw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=MM3j685o; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:4 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from howler.vger.email (howler.vger.email. [2620:137:e000::3:4]) by mx.google.com with ESMTPS id x11-20020a17090300cb00b001ca1bd194b4si5023830plc.416.2023.10.30.06.42.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Oct 2023 06:42:11 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:4 as permitted sender) client-ip=2620:137:e000::3:4; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20230601 header.b=MM3j685o; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:4 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id 9438B804BC36; Mon, 30 Oct 2023 06:42:05 -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 S233364AbjJ3NNI (ORCPT + 31 others); Mon, 30 Oct 2023 09:13:08 -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-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 X-Spam-Status: No, score=-0.6 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 howler.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 (howler.vger.email [0.0.0.0]); Mon, 30 Oct 2023 06:42:05 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1781188087192362150 X-GMAIL-MSGID: 1781188087192362150 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().