Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752322AbXKRQsc (ORCPT ); Sun, 18 Nov 2007 11:48:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751042AbXKRQsY (ORCPT ); Sun, 18 Nov 2007 11:48:24 -0500 Received: from x346.tv-sign.ru ([89.108.83.215]:48123 "EHLO mail.screens.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750984AbXKRQsX (ORCPT ); Sun, 18 Nov 2007 11:48:23 -0500 Date: Sun, 18 Nov 2007 19:48:34 +0300 From: Oleg Nesterov To: Andrew Morton Cc: Roland McGrath , linux-kernel@vger.kernel.org Subject: [PATCH] use __set_task_state() for TRACED/STOPPED tasks Message-ID: <20071118164834.GA3383@tv-sign.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2530 Lines: 66 1. It is much easier to grep for ->state change if __set_task_state() is used instead of the direct assignment. 2. ptrace_stop() and handle_group_stop() use set_task_state() which adds the unneeded mb() (btw even if we use mb() it is still possible that do_wait() sees the new ->state but not ->exit_code, but this is ok). Signed-off-by: Oleg Nesterov --- 24/kernel/fork.c~state 2007-11-09 12:57:31.000000000 +0300 +++ 24/kernel/fork.c 2007-11-18 19:27:38.000000000 +0300 @@ -1462,7 +1462,7 @@ long do_fork(unsigned long clone_flags, if (!(clone_flags & CLONE_STOPPED)) wake_up_new_task(p, clone_flags); else - p->state = TASK_STOPPED; + __set_task_state(p, TASK_STOPPED); if (unlikely (trace)) { current->ptrace_message = nr; --- 24/kernel/ptrace.c~state 2007-10-25 16:22:12.000000000 +0400 +++ 24/kernel/ptrace.c 2007-11-18 19:30:20.000000000 +0300 @@ -53,7 +53,7 @@ void ptrace_untrace(struct task_struct * spin_lock(&child->sighand->siglock); if (child->state == TASK_TRACED) { if (child->signal->flags & SIGNAL_STOP_STOPPED) { - child->state = TASK_STOPPED; + __set_task_state(child, TASK_STOPPED); } else { signal_wake_up(child, 1); } @@ -104,7 +104,7 @@ int ptrace_check_attach(struct task_stru ret = 0; spin_lock_irq(&child->sighand->siglock); if (child->state == TASK_STOPPED) { - child->state = TASK_TRACED; + __set_task_state(child, TASK_TRACED); } else if (child->state != TASK_TRACED && !kill) { ret = -ESRCH; } --- 24/kernel/signal.c~state 2007-11-09 12:57:31.000000000 +0300 +++ 24/kernel/signal.c 2007-11-18 19:33:19.000000000 +0300 @@ -1617,7 +1617,7 @@ static void ptrace_stop(int exit_code, i current->exit_code = exit_code; /* Let the debugger run. */ - set_current_state(TASK_TRACED); + __set_current_state(TASK_TRACED); spin_unlock_irq(¤t->sighand->siglock); try_to_freeze(); read_lock(&tasklist_lock); @@ -1781,7 +1781,7 @@ static int handle_group_stop(void) if (stop_count == 0) current->signal->flags = SIGNAL_STOP_STOPPED; current->exit_code = current->signal->group_exit_code; - set_current_state(TASK_STOPPED); + __set_current_state(TASK_STOPPED); spin_unlock_irq(¤t->sighand->siglock); finish_stop(stop_count); return 1; - 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/