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 AAEE6C433F5 for ; Mon, 14 Feb 2022 19:51:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229652AbiBNTvW (ORCPT ); Mon, 14 Feb 2022 14:51:22 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:53898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229468AbiBNTvU (ORCPT ); Mon, 14 Feb 2022 14:51:20 -0500 Received: from mail-pf1-x42f.google.com (mail-pf1-x42f.google.com [IPv6:2607:f8b0:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 54F381275FC for ; Mon, 14 Feb 2022 11:51:04 -0800 (PST) Received: by mail-pf1-x42f.google.com with SMTP id m22so11824246pfk.6 for ; Mon, 14 Feb 2022 11:51:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=xfLlstyLrwocScqIOv+14Ypez3TInqIWV7B8q26ohT4=; b=PWrWd5BhgiJFgXs3u+v2SLDwgqgvXNE6iuwpaJubHXLScyqY7eJ2F/xsbEUCo2RejS kLWQXfTg5BPh68bdMlmp5e4O4LZSjtZEAb8ZxjV3ZXbBfDWqJJEyLzai6/kXIjQnfy7I fI2vrpuoJu0Z7URJNXtL+UpNGPyl6yIYIxmVycsGQOzqcvwuTIfR5wzzYmH6NrLPH1eg aqvNORdlYlyTIo09FT0bXwpkLEPLRPpMzgJZbCxSPDWGOgA3KwPBc4Relao+NPKrIn0u sbVch78jwJZm7m/3kY8Ylj4zBA+VDk1PxkZC0fhy9o+PhG8x52FOKtnt3Y7cbvVqKwPb sFpg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=xfLlstyLrwocScqIOv+14Ypez3TInqIWV7B8q26ohT4=; b=ETCu0KB1okwSMpX5/DHUVTcjaIQy61M+zI29EyC6RDMZkT0cAGVQzqvAvrubxuq+to ZHb61H3Lyxb43sQu/jI8O6welWQoCzhpe3nnEcqrU4fez1qxCMzq6JsU64IPmDcHnEoM LPfmV4f3KSYxF62bDqfd/FS8VMAHWh3GKA3VUbCEzs9EVNn9vAZx7CNxraRU7OTZCI6/ nvw4S77POZikAtoM8I14e9hh6bZC+xONyybNmlFDNjJIYWNIAGHCaFIaszyt/jZosS/i Kce5QReEMVCAa14YVUWtLXeCgNb5WlhALalRPn/aeERfnTTS3jI4njNSnsxKL76w1bKA bd+g== X-Gm-Message-State: AOAM531aVfD5Ohzq9HozmwZwhA+fUHaou1aTEdWhelmCQHa4YvTE4zXo rGZC14u450eh8gkwgXzskxM= X-Google-Smtp-Source: ABdhPJzWYLn7LUF0I4vIIdv406pNxtyWp4SRIXGlYTIZYXAXlFhiK83IpHrz8Q2PLVHkvreB3rYOMw== X-Received: by 2002:a63:cc43:: with SMTP id q3mr491233pgi.243.1644867977018; Mon, 14 Feb 2022 11:46:17 -0800 (PST) Received: from localhost (2603-800c-1a02-1bae-e24f-43ff-fee6-449f.res6.spectrum.com. [2603:800c:1a02:1bae:e24f:43ff:fee6:449f]) by smtp.gmail.com with ESMTPSA id i4sm2935509pfq.105.2022.02.14.11.46.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Feb 2022 11:46:16 -0800 (PST) Sender: Tejun Heo Date: Mon, 14 Feb 2022 09:46:15 -1000 From: Tejun Heo To: Peter Zijlstra Cc: Linus Torvalds , Borislav Petkov , Tadeusz Struk , x86-ml , lkml , zhangqiao22@huawei.com, dietmar.eggemann@arm.com Subject: Re: [GIT PULL] sched/urgent for 5.17-rc4 Message-ID: References: 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 On Mon, Feb 14, 2022 at 08:35:54PM +0100, Peter Zijlstra wrote: > So there's two things that need doing; the re-cloning of the task_group > thing, but also calling of __set_task_cpu() which sets up the proper > runqueue links. > > The first is CGroup only, and *could* in theory be done in ->can_fork(), > but the second needs to be done unconditionally, and it doesn't make > much sense to split this up. > > I actually tried, but it made the patch bigger/uglier -- but maybe I > didn't try hard enough. If there needs to be a separate call anyway, it prolly is better to keep them together. It'd just be nice to mention why cpu is different in this regard in a comment. Thanks. -- tejun