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 E223CC4332F for ; Tue, 12 Dec 2023 17:14:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234999AbjLLROs (ORCPT ); Tue, 12 Dec 2023 12:14:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234944AbjLLROq (ORCPT ); Tue, 12 Dec 2023 12:14:46 -0500 Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CE12E9F for ; Tue, 12 Dec 2023 09:14:52 -0800 (PST) Received: by mail-pl1-x636.google.com with SMTP id d9443c01a7336-1d343f8e139so3269205ad.0 for ; Tue, 12 Dec 2023 09:14:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702401292; x=1703006092; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=OOmVxyvlV9iC91AJreDAWLoQkSzQ2NPxXA9m17q8MxY=; b=b7pAbrzr6VIlhGCfNZIuie1yBO3ZO+FRSRO7bH+PQ7EeJtVsKvROlTzTOwOyBaK6Qy +fM9XuSO6IXyzjYCfBVbcB17qj3gik6SCKWiEzSaOfQg1PILl1l2P0ysM0dyO/l6lO02 9UoG9wdCtZZKsrc3+2TBOWANmpuMQ+6RXsLni5xbkmq5dZQcwjRmuNMIF9wOMp8SaCfg l21mzp6VXcBsci8DKewH/XY0WEJ3mqS8RuGSnkCKt6546ZoAgAy8GUiJtUtpATxvNcZQ x/EU2sYUdgCiMX2U5su61Voc7rkX6B0Zhj1caiCO62OUcXYHz3LDdoIcRpapYadTiErN ubnw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702401292; x=1703006092; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=OOmVxyvlV9iC91AJreDAWLoQkSzQ2NPxXA9m17q8MxY=; b=gjE8u3rzK6LB72pkX8Rhx6oACZXEKURTXSvWOD1uA7T/wkZOS+lDIfXwFmWowoVsGY peQEZt04gEONimQ+QAIl/pvBiud4PyIGxg6U0iWdQSqn/9Il3vDwjOfIYUAzEIKmw3aa E8ctezPmBdnWRzZZ4TBGFOgP/Yu1Pw0kKEBL5Lb2JNwrzxnjQ3VsyRvO+DXwWEVKbbDd X71JyN5waJGXsHcwvZ4nNDi+edXlG73VMxh+Stu3Q4Vsbr5LzTGR+rbX1IAQNgIdSAo8 Z4xWT4f3Ghh7tGT/SEmirwb8MdY1ETWifm3ybhAOBZfrqPStlgn1RXW3VezZHSilsfER ZvXw== X-Gm-Message-State: AOJu0Yx0FxMi+HdWuszpNZoLKKX1dxtBy1pTTG/OB2aMZavzPcYGQIAI U+eCEQr2lTiuMICInhKQgwE= X-Google-Smtp-Source: AGHT+IGj1R0cYd/c1GD99AOTF4Uco9bwWxEs4SagyXZt3mu96Srr1MFzMlXgV0/GDKsu1I56Q7xFyw== X-Received: by 2002:a17:902:bc4c:b0:1d0:91a0:a29 with SMTP id t12-20020a170902bc4c00b001d091a00a29mr3127951plz.6.1702401292134; Tue, 12 Dec 2023 09:14:52 -0800 (PST) Received: from localhost (dhcp-72-253-202-210.hawaiiantel.net. [72.253.202.210]) by smtp.gmail.com with ESMTPSA id z14-20020a170903018e00b001cfc15993efsm8896620plg.163.2023.12.12.09.14.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 12 Dec 2023 09:14:50 -0800 (PST) Sender: Tejun Heo Date: Tue, 12 Dec 2023 07:14:48 -1000 From: Tejun Heo To: Juri Lelli Cc: Aaron Tomlin , linux-kernel@vger.kernel.org, jiangshanlai@gmail.com, peterz@infradead.org Subject: Re: [RFC PATCH 0/2] workqueue: Introduce PF_WQ_RESCUE_WORKER Message-ID: References: <20230729135334.566138-1-atomlin@atomlin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Juri. On Tue, Dec 12, 2023 at 10:56:02AM +0100, Juri Lelli wrote: > Hummm, OK, but in terms of which CPU the rescuer is possibly woken up, > how are we making sure that the wake up is always happening on > housekeeping CPUs (assuming unbound workqueues have been restricted to > those)? > > AFAICS, we have > > send_mayday -> > wake_up_process(wq->rescuer->task) > > which is not affined to the workqueue cpumask it's called to rescue, so > in theory can be woken up anywhere? Ah, was only thinking about work item execution. Yeah, it's not following the isolation rule there and we probably should affine it as we're waking it up. Thanks. -- tejun