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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 15818C6778D for ; Wed, 12 Sep 2018 16:43:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4ACF20833 for ; Wed, 12 Sep 2018 16:43:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A4ACF20833 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727839AbeILVsT (ORCPT ); Wed, 12 Sep 2018 17:48:19 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:46370 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726854AbeILVsT (ORCPT ); Wed, 12 Sep 2018 17:48:19 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AAEBC809367A; Wed, 12 Sep 2018 16:33:14 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.34.27.30]) by smtp.corp.redhat.com (Postfix) with SMTP id 48401A9E5E; Wed, 12 Sep 2018 16:33:13 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 12 Sep 2018 18:33:14 +0200 (CEST) Date: Wed, 12 Sep 2018 18:33:12 +0200 From: Oleg Nesterov To: Andrew Morton Cc: Dmitry Vyukov , Michal Hocko , "Paul E. McKenney" , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: [PATCH 0/2] introduce for_each_process_thread_break() and for_each_process_thread_continue() Message-ID: <20180912163312.GA18739@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Wed, 12 Sep 2018 16:33:14 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Wed, 12 Sep 2018 16:33:14 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'oleg@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Resend. IMHO this makes sense anyway, but mostly this is preparation for other changes. show_state_filter() and other "slow" users of for_each_process() can livelock and even trigger hard lockups. Peter, you have already reviewed at least 1/2 (heh, two years ago) and iirc you were mostly agree but pointed out that for_each_xxx() in _continue() could be SPEND_TOO_MUCH_TIME themselves. I added a note into the changelog. Oleg. include/linux/sched/signal.h | 10 ++++++++++ kernel/exit.c | 42 ++++++++++++++++++++++++++++++++++++++++++ kernel/hung_task.c | 25 +++++++++---------------- 3 files changed, 61 insertions(+), 16 deletions(-)