From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753127AbdFOS2m (ORCPT ); Thu, 15 Jun 2017 14:28:42 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:54026 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751858AbdFOR4y (ORCPT ); Thu, 15 Jun 2017 13:56:54 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.4 42/46] proc: add a schedule point in proc_pid_readdir() Date: Thu, 15 Jun 2017 19:53:01 +0200 Message-Id: <20170615175220.287112914@linuxfoundation.org> X-Mailer: git-send-email 2.13.1 In-Reply-To: <20170615175218.286057711@linuxfoundation.org> References: <20170615175218.286057711@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 3ba4bceef23206349d4130ddf140819b365de7c8 ] We have seen proc_pid_readdir() invocations holding cpu for more than 50 ms. Add a cond_resched() to be gentle with other tasks. [akpm@linux-foundation.org: coding style fix] Link: http://lkml.kernel.org/r/1484238380.15816.42.camel@edumazet-glaptop3.roam.corp.google.com Signed-off-by: Eric Dumazet Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/proc/base.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -3058,6 +3058,8 @@ int proc_pid_readdir(struct file *file, iter.tgid += 1, iter = next_tgid(ns, iter)) { char name[PROC_NUMBUF]; int len; + + cond_resched(); if (!has_pid_permissions(ns, iter.task, 2)) continue;