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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74E72ECAAA1 for ; Wed, 7 Sep 2022 02:43:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229903AbiIGCn2 (ORCPT ); Tue, 6 Sep 2022 22:43:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229862AbiIGCnZ (ORCPT ); Tue, 6 Sep 2022 22:43:25 -0400 Received: from mail-qt1-x82c.google.com (mail-qt1-x82c.google.com [IPv6:2607:f8b0:4864:20::82c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D6E097B28F for ; Tue, 6 Sep 2022 19:43:24 -0700 (PDT) Received: by mail-qt1-x82c.google.com with SMTP id c20so9483011qtw.8 for ; Tue, 06 Sep 2022 19:43:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date; bh=HV15brfmijT3wQpdJQzUr20Idn6RQgfVceZTRDNZ2RA=; b=xSduQWMCYeluZayNSc/ZHmsirDlb9V9NS3hqmtpoPmuCjOI6hsnymMlm4dMQTQDGPD J4T0+VqM2skudfqpfnDEGffA6LwWX9ZtfksqaBf8mewmSP1nOEi35pcZO/f3PgmlKhHl hw2/IvrXMUi65QTYz6e377fymvUm0PBmBkNQk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date; bh=HV15brfmijT3wQpdJQzUr20Idn6RQgfVceZTRDNZ2RA=; b=FHp577SCLQvBpirtENWtTN687ytqFmVOz83t/YaaBz3/+rzADpRY7P8lKyUFTkVL8l 7x/9NOPkmcfM9AiUFsbV9cJyI1XefCZqBQOaG2HBBSpJRTlUe9JUuDpyhPella5gVTD1 AY6ha9++7G24/0vMSksgeSYKb0Tez66MASdOvIpcddknYDvN9h8Mf0oVfzoBwIu38qe/ Fpy/3ppAL004db7PQT19X26/WQyXFW2b9cd4QZwuS9FGmwBcYhlK0e6PJleGR2+rZIvF YhRc+OtDxminFJFcNq0yObH5F6FpijtqS37LgXdwEhaT9KkLjCsqCVm4zbo2o94UM5QN pkgA== X-Gm-Message-State: ACgBeo2IMCJjbmfzJBgglC8ufrQZ7UpL5ndE/MBGt6RzPmq/5w3ZSEVB 59ogdKPC0z4Bs2AAWALOP4je/Q== X-Google-Smtp-Source: AA6agR4g8U9tCuV/rPUVPEgqT2qIUDioJHoiieKqfwpb7oxjTNDvFQ9Y6HTa+FzF7YlFKwIwyKTxpQ== X-Received: by 2002:ac8:5a0d:0:b0:344:de4f:b187 with SMTP id n13-20020ac85a0d000000b00344de4fb187mr1431577qta.136.1662518604011; Tue, 06 Sep 2022 19:43:24 -0700 (PDT) Received: from [10.0.0.40] (c-73-148-104-166.hsd1.va.comcast.net. [73.148.104.166]) by smtp.gmail.com with ESMTPSA id bb9-20020a05622a1b0900b00354e5b8bba3sm6629847qtb.29.2022.09.06.19.43.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 06 Sep 2022 19:43:23 -0700 (PDT) Message-ID: Date: Tue, 6 Sep 2022 22:43:22 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.2.1 Subject: Re: [PATCH v5 04/18] rcu: Fix late wakeup when flush of bypass cblist happens Content-Language: en-US To: Frederic Weisbecker Cc: rcu@vger.kernel.org, linux-kernel@vger.kernel.org, rushikesh.s.kadam@intel.com, urezki@gmail.com, neeraj.iitr10@gmail.com, paulmck@kernel.org, rostedt@goodmis.org, vineeth@bitbyteword.org, boqun.feng@gmail.com References: <20220901221720.1105021-1-joel@joelfernandes.org> <20220901221720.1105021-5-joel@joelfernandes.org> <20220906094852.GA174244@lothringen> From: Joel Fernandes In-Reply-To: <20220906094852.GA174244@lothringen> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/6/2022 5:48 AM, Frederic Weisbecker wrote: >> } >> - rcu_nocb_unlock_irqrestore(rdp, flags); >> + >> + // The flush succeeded and we moved CBs into the ->cblist. >> + // However, the bypass timer might still be running. Wakeup the > That part of the comment mentioning the bypass timer looks strange... > > >> + // GP thread by calling a helper with was_all_done set so that >> + // wake up happens (needed if main CB list was empty before). > How about: > > // The flush succeeded and we moved CBs into the regular list. > // Don't wait for the wake up timer as it may be too far ahead. > // Wake up now GP thread instead if the cblist was empty > > Thanks. > > Other than that the patch looks good, thanks! > I updated it accordingly and will send it for next revision, thank you! - Joel