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 DF24FC433FE for ; Fri, 22 Apr 2022 22:05:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231621AbiDVWHb (ORCPT ); Fri, 22 Apr 2022 18:07:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231719AbiDVWGy (ORCPT ); Fri, 22 Apr 2022 18:06:54 -0400 Received: from out01.mta.xmission.com (out01.mta.xmission.com [166.70.13.231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C35F829A8DD; Fri, 22 Apr 2022 13:51:51 -0700 (PDT) Received: from in02.mta.xmission.com ([166.70.13.52]:38310) by out01.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nhyrw-009dKx-2e; Fri, 22 Apr 2022 13:23:04 -0600 Received: from ip68-227-174-4.om.om.cox.net ([68.227.174.4]:35330 helo=email.froward.int.ebiederm.org.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nhyru-001u6V-Vt; Fri, 22 Apr 2022 13:23:03 -0600 From: "Eric W. Biederman" To: Sebastian Andrzej Siewior Cc: Peter Zijlstra , rjw@rjwysocki.net, oleg@redhat.com, mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, Will Deacon , linux-kernel@vger.kernel.org, tj@kernel.org, linux-pm@vger.kernel.org References: <20220421150248.667412396@infradead.org> Date: Fri, 22 Apr 2022 14:15:35 -0500 In-Reply-To: (Sebastian Andrzej Siewior's message of "Fri, 22 Apr 2022 19:43:18 +0200") Message-ID: <878rrxnd48.fsf@email.froward.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1nhyru-001u6V-Vt;;;mid=<878rrxnd48.fsf@email.froward.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.174.4;;;frm=ebiederm@xmission.com;;;spf=softfail X-XM-AID: U2FsdGVkX19hvqqRkMVEC3l3uQe4MMAWSxUUPffs0mA= X-SA-Exim-Connect-IP: 68.227.174.4 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH v2 0/5] ptrace-vs-PREEMPT_RT and freezer rewrite X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sebastian Andrzej Siewior writes: > On 2022-04-21 17:02:48 [+0200], Peter Zijlstra wrote: >> Find here a new posting of the ptrace and freezer patches :-) >> >> The majority of the changes are in patch 2, which with much feedback from Oleg >> and Eric has changed lots. >> >> I'm hoping we're converging on something agreeable. > > I tested this under RT (had to remove the preempt-disable section in > ptrace_stop()) with ssdd [0]. It forks a few tasks and then > PTRACE_SINGLESTEPs them for a few iterations. Out of curiosity why did you need to remove the preempt_disable section on PREEMPT_RT? It should have lasted for just a moment until schedule was called. Eric