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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 98041C433B4 for ; Thu, 8 Apr 2021 19:44:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C8E061025 for ; Thu, 8 Apr 2021 19:44:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232657AbhDHToo (ORCPT ); Thu, 8 Apr 2021 15:44:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232432AbhDHTog (ORCPT ); Thu, 8 Apr 2021 15:44:36 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3B8F2C061761 for ; Thu, 8 Apr 2021 12:44:25 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id l1so1575792plg.12 for ; Thu, 08 Apr 2021 12:44:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=bfastjAcTH6GvPwsRgj4kE1AV0IU20Avq5QkV1jf3r4=; b=EJAHG+Uic46Jnmh+49aazvcUkUVTtFlYpkrr7bKQDNzWmlAzr7wuVZCTqKnJo576Uj I6caQ9M3WepGXq8KfauX3Kz0E4DW5cZMtRc4OR/R9wPAWKD2BOLF/z2KXK3AGQy+J3aG 3H7UueJOv+dgTrAgF/+TiTbJUHBGezmWFYx5BXdLZrGBu7xfJ57v+rJbewkEf5hVQ5i7 dn9oyKikDARyd1AFWtyKSu1bZkW3Cb+0qtsEUNT8dRp8ai7CcNcDKip3rcUZZlhsFjbW pZNBXKU1Uo9E8jDdZm/cc5iIgOj3DgQbJNiVB3JVCDe93ggFZXOBWgDBgSly8WXXwkpJ XbQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=bfastjAcTH6GvPwsRgj4kE1AV0IU20Avq5QkV1jf3r4=; b=d5PMeGfEtCExrOZAeNr9wckqza4jFRZxgC2LB09ymsC1qLLsleFx7DUeFHJt7dFAFy mkYihf1oCgpgEw7Op6h3QLAKxzJhGcEs6ROqktCmGQFY2OoxH+cv+WzFdh9vrKPpv/WJ EqcWN3yEQJ2q0+en6efAA/sPFI3Xi9vESwtSASQyNxlwM4pBeSFg3eavf1ZCO+GPy4Wn K0aEjK3Uc9c7rjiMdD22SzqLWQPVkIFxc4uX8wccB4rJUhSvfZtFeNjSoooMGzkO8+2E UZ1/s52gkcE7l+aUAtzM/chHgKc0ABtgCrQ+8aG+Y3psifB5AwW4T8xjRvLupTzGVyfm Gyog== X-Gm-Message-State: AOAM532YFRyHNSq18K6jxFKfwV6GPJ0UxYqr9sOzEdkhCnpMoFeuMQZD 3U0jsniZXOBHtRdKQbSS2y+1UGieGe53mg== X-Google-Smtp-Source: ABdhPJwLOPv5mYkBNpJyACmTwL9RSZ7tTYjT58P3V4Ml4mAfiOEPPlBWb3tBEh7V6+dxN64G/duR4A== X-Received: by 2002:a17:90a:300f:: with SMTP id g15mr4386373pjb.88.1617911064537; Thu, 08 Apr 2021 12:44:24 -0700 (PDT) Received: from [192.168.4.41] (cpe-72-132-29-68.dc.res.rr.com. [72.132.29.68]) by smtp.gmail.com with ESMTPSA id q10sm168327pgs.44.2021.04.08.12.44.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 08 Apr 2021 12:44:24 -0700 (PDT) Subject: Re: [PATCH] block: Fix sys_ioprio_set(.which=IOPRIO_WHO_PGRP) task iteration To: Peter Zijlstra , Oleg Nesterov Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: From: Jens Axboe Message-ID: Date: Thu, 8 Apr 2021 13:44:23 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/8/21 3:46 AM, Peter Zijlstra wrote: > > do_each_pid_thread() { } while_each_pid_thread() is a double loop and > thus break doesn't work as expected. Also, it should be used under > tasklist_lock because otherwise we can race against change_pid() for > PGID/SID. Applied, thanks. -- Jens Axboe