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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD150C4361B for ; Wed, 16 Dec 2020 14:33:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77C2C233EA for ; Wed, 16 Dec 2020 14:33:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726565AbgLPOdg (ORCPT ); Wed, 16 Dec 2020 09:33:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726558AbgLPOdg (ORCPT ); Wed, 16 Dec 2020 09:33:36 -0500 Received: from mail-qk1-x729.google.com (mail-qk1-x729.google.com [IPv6:2607:f8b0:4864:20::729]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E822DC061794 for ; Wed, 16 Dec 2020 06:32:55 -0800 (PST) Received: by mail-qk1-x729.google.com with SMTP id z11so22630054qkj.7 for ; Wed, 16 Dec 2020 06:32:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=SccFDNBIkslfgiob32PkKVek28skifxxI2wxs+TjvJg=; b=sF01LXuNIGaD7nij1Lh4lzd5CDc7S5YQk1iL/Uwn/IMskkD1ZsofgG23b7Fc76baax 565GYyG3Kt2PEtWAQ9mo+kXAh7MGkxEReYUa+1ETLwqX1CLP2qnI/40+I7MvEicNfiNs Eu0UaWzjPeWvk89mMpBjuvTikdsF6bOW1oRt3S2JM7suEKGgcc7x/RLNmSfvsWIjeWt6 ew5iJbNuEc6hOY7JD7+efi9y0KJ+qId/BRyEVMZDPqBcacUDLnL2XanmfauzlI5+WEVU qnn+mq+BNzScOR4zRiFhd/M0tkuj7VITuxa1aHQCM+WBpqEvaGEpdbuEh/8naHE2js+L /rdw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=SccFDNBIkslfgiob32PkKVek28skifxxI2wxs+TjvJg=; b=rxQkIsb2Aq8ECjB257nZ+SkTLrwlV5wr+md6ur9+WwHV9Dktgrbm5wDff2buXwzkIy FSOsPKMSu7KxRvx2qoYNa2KrLKtg9MGLWeAYOVK6KOOH30s6Nfbd5aUKQBy/bUduJa2x 5yI+xU4Lh6euNPXcXw1rl0hBkr3JVF78v+j6wa0pW5XIGUjWnhBsv2yjImMnMhSSNZ3k rf7VZ7/Vkf0qZzA2OSe3Grj3JBmhggUBOJvqoApeY2XYY/LkvjzAiL2yjvuLKNBIRzIQ /S4Tr4NoO3d7p76tNsuxmxlGJ4i9PDEvjJP3Cu/ScZFa7X8C5j1VrdElANVkUdPH0APd jLkA== X-Gm-Message-State: AOAM531/8YBQRRr//ZrA7kH0MyX7Ihq79j2V0HpH3lPwBqiNMfxHuzmp RKGj2jxGhIcFu71G/61T2oufvdVMnPWhhg== X-Google-Smtp-Source: ABdhPJymMyNu6EvzltRUHf7pjiZxIeafFZCas7sdOfWSKhvHeCHAM5hNcomaR+UJ368ILGMJKlI3pA== X-Received: by 2002:a37:a713:: with SMTP id q19mr42120373qke.23.1608129175091; Wed, 16 Dec 2020 06:32:55 -0800 (PST) Received: from localhost ([2620:10d:c091:480::1:cbde]) by smtp.gmail.com with ESMTPSA id a5sm1083363qtn.57.2020.12.16.06.32.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Dec 2020 06:32:54 -0800 (PST) Sender: Tejun Heo Date: Wed, 16 Dec 2020 09:32:21 -0500 From: Tejun Heo To: Lai Jiangshan Cc: linux-kernel@vger.kernel.org, Lai Jiangshan , Peter Zijlstra , Valentin Schneider , Daniel Bristot de Oliveira Subject: Re: [PATCH 02/10] workqueue: use cpu_possible_mask instead of cpu_active_mask to break affinity Message-ID: References: <20201214155457.3430-1-jiangshanlai@gmail.com> <20201214155457.3430-3-jiangshanlai@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201214155457.3430-3-jiangshanlai@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Mon, Dec 14, 2020 at 11:54:49PM +0800, Lai Jiangshan wrote: > @@ -4909,8 +4909,9 @@ static void unbind_workers(int cpu) > > raw_spin_unlock_irq(&pool->lock); > > + /* don't rely on the scheduler to force break affinity for us. */ I'm not sure this comment is helpful. The comment may make sense right now while the scheduler behavior is changing but down the line it's not gonna make whole lot of sense. > for_each_pool_worker(worker, pool) > - WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_active_mask) < 0); > + WARN_ON_ONCE(set_cpus_allowed_ptr(worker->task, cpu_possible_mask) < 0); > > mutex_unlock(&wq_pool_attach_mutex); Thanks. -- tejun