Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932275Ab1FPTyH (ORCPT ); Thu, 16 Jun 2011 15:54:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36620 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758141Ab1FPTyC (ORCPT ); Thu, 16 Jun 2011 15:54:02 -0400 Date: Thu, 16 Jun 2011 21:51:38 +0200 From: Oleg Nesterov To: Tejun Heo Cc: vda.linux@googlemail.com, jan.kratochvil@redhat.com, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, indan@nul.nu, bdonlan@gmail.com, pedro@codesourcery.com Subject: Re: [PATCH 4/5] ptrace: implement TRAP_NOTIFY and use it for group stop events Message-ID: <20110616195138.GB14786@redhat.com> References: <1308043218-23619-1-git-send-email-tj@kernel.org> <1308043218-23619-5-git-send-email-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1308043218-23619-5-git-send-email-tj@kernel.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1307 Lines: 34 On 06/14, Tejun Heo wrote: > > When group stop state of a seized tracee changes, JOBCTL_TRAP_NOTIFY > is set, I already applied this series. But somehow I have the fuzzy feeling we can simplify JOBCTL_TRAP_NOTIFY/JOBCTL_TRAP_STOP logic later. No, I can't explain what I mean ;) One question, > @@ -1797,8 +1824,10 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info) > if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING)) > gstop_done = task_participate_group_stop(current); > > - /* any trap clears pending STOP trap */ > + /* any trap clears pending STOP trap, STOP trap clears NOTIFY */ > task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); > + if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) > + task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); OK, but can't we check why == CLD_STOPPED instead of PTRACE_EVENT_STOP? In fact, can't we move all code above under 'if (why == CLD_STOPPED)' ? JOBCTL_TRAP_STOP can't be set otherwise, no? I am almost sure I missed something though. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/