From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754413Ab2BPSRw (ORCPT ); Thu, 16 Feb 2012 13:17:52 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50278 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754327Ab2BPSRt (ORCPT ); Thu, 16 Feb 2012 13:17:49 -0500 Date: Thu, 16 Feb 2012 18:27:24 +0100 From: Oleg Nesterov To: Andrew Morton Cc: apw@canonical.com, arjan@linux.intel.com, fhrbata@redhat.com, john.johansen@canonical.com, penguin-kernel@I-love.SAKURA.ne.jp, rientjes@google.com, rusty@rustcorp.com.au, tj@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/4] coredump_wait: don't call complete_vfork_done() Message-ID: <20120216172724.GD30393@redhat.com> References: <20120214164709.GA21178@redhat.com> <20120214164914.GF21185@redhat.com> <20120215123049.6e938eed.akpm@linux-foundation.org> <20120216150429.GB11953@redhat.com> <20120216172626.GA30393@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120216172626.GA30393@redhat.com> 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 Now that CLONE_VFORK is killable, coredump_wait() no longer needs complete_vfork_done(). zap_threads() should find and kill all tasks with the same ->mm, this includes our parent if ->vfork_done is set. mm_release() becomes the only caller, unexport complete_vfork_done(). Signed-off-by: Oleg Nesterov Acked-by: Tejun Heo --- fs/exec.c | 14 ++------------ include/linux/sched.h | 1 - kernel/fork.c | 2 +- 3 files changed, 3 insertions(+), 14 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index dccdcec..153dee1 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1926,19 +1926,9 @@ static int coredump_wait(int exit_code, struct core_state *core_state) core_waiters = zap_threads(tsk, mm, core_state, exit_code); up_write(&mm->mmap_sem); - if (unlikely(core_waiters < 0)) - goto fail; - - /* - * Make sure nobody is waiting for us to release the VM, - * otherwise we can deadlock when we wait on each other - */ - if (tsk->vfork_done) - complete_vfork_done(tsk); - - if (core_waiters) + if (core_waiters > 0) wait_for_completion(&core_state->startup); -fail: + return core_waiters; } diff --git a/include/linux/sched.h b/include/linux/sched.h index b646771..11fcafa 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2291,7 +2291,6 @@ extern int do_execve(const char *, const char __user * const __user *, const char __user * const __user *, struct pt_regs *); extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *); -extern void complete_vfork_done(struct task_struct *tsk); struct task_struct *fork_idle(int); extern void set_task_comm(struct task_struct *tsk, char *from); diff --git a/kernel/fork.c b/kernel/fork.c index fc2c2f0..57ebebb 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -667,7 +667,7 @@ struct mm_struct *mm_access(struct task_struct *task, unsigned int mode) return mm; } -void complete_vfork_done(struct task_struct *tsk) +static void complete_vfork_done(struct task_struct *tsk) { struct completion *vfork; -- 1.5.5.1