Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751578AbWHZOyF (ORCPT ); Sat, 26 Aug 2006 10:54:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751585AbWHZOyF (ORCPT ); Sat, 26 Aug 2006 10:54:05 -0400 Received: from taganka54-host.corbina.net ([213.234.233.54]:20451 "EHLO screens.ru") by vger.kernel.org with ESMTP id S1751578AbWHZOyC (ORCPT ); Sat, 26 Aug 2006 10:54:02 -0400 Date: Sat, 26 Aug 2006 23:18:17 +0400 From: Oleg Nesterov To: Ingo Molnar Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: [PATCH 3/3] introduce TASK_DEAD state Message-ID: <20060826191817.GA173@oleg> 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: 3350 Lines: 82 I am not sure about this patch, I am asking Ingo to take a decision. task_struct->state == EXIT_DEAD is a very special case, to avoid a confusion it makes sense to introduce a new state, TASK_DEAD, while EXIT_DEAD should live only in ->exit_state as documented in sched.h. Note that this state is not visible to user-space, get_task_state() masks off unsuitable states. Signed-off-by: Oleg Nesterov --- 2.6.18-rc4/include/linux/sched.h~3_rename 2006-08-26 21:28:54.000000000 +0400 +++ 2.6.18-rc4/include/linux/sched.h 2006-08-26 23:03:44.000000000 +0400 @@ -148,6 +148,7 @@ extern unsigned long weighted_cpuload(co #define EXIT_DEAD 32 /* in tsk->state again */ #define TASK_NONINTERACTIVE 64 +#define TASK_DEAD 128 #define __set_task_state(tsk, state_value) \ do { (tsk)->state = (state_value); } while (0) --- 2.6.18-rc4/kernel/exit.c~3_rename 2006-08-26 21:46:45.000000000 +0400 +++ 2.6.18-rc4/kernel/exit.c 2006-08-26 22:31:50.000000000 +0400 @@ -955,7 +955,7 @@ fastcall NORET_TYPE void do_exit(long co preempt_disable(); /* causes final put_task_struct in finish_task_switch(). */ - tsk->state = EXIT_DEAD; + tsk->state = TASK_DEAD; schedule(); BUG(); --- 2.6.18-rc4/kernel/sched.c~3_rename 2006-08-26 21:56:46.000000000 +0400 +++ 2.6.18-rc4/kernel/sched.c 2006-08-26 22:37:48.000000000 +0400 @@ -1751,10 +1751,10 @@ static inline void finish_task_switch(st /* * A task struct has one reference for the use as "current". - * If a task dies, then it sets EXIT_DEAD in tsk->state and calls + * If a task dies, then it sets TASK_DEAD in tsk->state and calls * schedule one last time. The schedule call will never return, and * the scheduled task must drop that reference. - * The test for EXIT_DEAD must occur while the runqueue locks are + * The test for TASK_DEAD must occur while the runqueue locks are * still held, otherwise prev could be scheduled on another cpu, die * there before we look at prev->state, and then the reference would * be dropped twice. @@ -1765,7 +1765,7 @@ static inline void finish_task_switch(st finish_lock_switch(rq, prev); if (mm) mmdrop(mm); - if (unlikely(prev_state == EXIT_DEAD)) { + if (unlikely(prev_state == TASK_DEAD)) { /* * Remove function-return probe instances associated with this * task and put them back on the free list. @@ -5116,7 +5116,7 @@ static void migrate_dead(unsigned int de BUG_ON(p->exit_state != EXIT_ZOMBIE && p->exit_state != EXIT_DEAD); /* Cannot have done final schedule yet: would have vanished. */ - BUG_ON(p->state == EXIT_DEAD); + BUG_ON(p->state == TASK_DEAD); get_task_struct(p); --- 2.6.18-rc4/mm/oom_kill.c~3_rename 2006-08-26 21:34:04.000000000 +0400 +++ 2.6.18-rc4/mm/oom_kill.c 2006-08-26 22:34:35.000000000 +0400 @@ -206,7 +206,7 @@ static struct task_struct *select_bad_pr */ releasing = test_tsk_thread_flag(p, TIF_MEMDIE) || p->flags & PF_EXITING; - if (releasing && (p->state != EXIT_DEAD)) + if (releasing && (p->state != TASK_DEAD)) return ERR_PTR(-1UL); if (p->flags & PF_SWAPOFF) return p; - 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/