Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261820AbVEVOuH (ORCPT ); Sun, 22 May 2005 10:50:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261818AbVEVOto (ORCPT ); Sun, 22 May 2005 10:49:44 -0400 Received: from mail.tv-sign.ru ([213.234.233.51]:26518 "EHLO several.ru") by vger.kernel.org with ESMTP id S261816AbVEVOtQ (ORCPT ); Sun, 22 May 2005 10:49:16 -0400 Message-ID: <42909DC2.7922E05D@tv-sign.ru> Date: Sun, 22 May 2005 18:57:06 +0400 From: Oleg Nesterov X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.20 i686) X-Accept-Language: en MIME-Version: 1.0 To: George Anzinger Cc: linux-kernel@vger.kernel.org, Andrew Morton Subject: [PATCH rc4-mm2 2/2] posix-timers: use try_to_del_timer_sync() Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3466 Lines: 103 sys_timer_settime/sys_timer_delete needs to delete k_itimer->real.timer synchronously while holding ->it_lock, which is also locked in posix_timer_fn. This patch removes timer_active/set_timer_inactive which plays with timer_list's internals in favour of using try_to_del_timer_sync(), which was introduced in the previous patch. Signed-off-by: Oleg Nesterov --- 2.6.12-rc4-mm2/kernel/posix-timers.c~2_USE 2005-04-30 18:05:29.000000000 +0400 +++ 2.6.12-rc4-mm2/kernel/posix-timers.c 2005-05-22 18:34:10.000000000 +0400 @@ -89,23 +89,6 @@ static struct idr posix_timers_id; static DEFINE_SPINLOCK(idr_lock); /* - * Just because the timer is not in the timer list does NOT mean it is - * inactive. It could be in the "fire" routine getting a new expire time. - */ -#define TIMER_INACTIVE 1 - -#ifdef CONFIG_SMP -# define timer_active(tmr) \ - ((tmr)->it.real.timer.entry.prev != (void *)TIMER_INACTIVE) -# define set_timer_inactive(tmr) \ - do { \ - (tmr)->it.real.timer.entry.prev = (void *)TIMER_INACTIVE; \ - } while (0) -#else -# define timer_active(tmr) BARFY // error to use outside of SMP -# define set_timer_inactive(tmr) do { } while (0) -#endif -/* * we assume that the new SIGEV_THREAD_ID shares no bits with the other * SIGEV values. Here we put out an error if this assumption fails. */ @@ -226,7 +209,6 @@ static inline int common_timer_create(st init_timer(&new_timer->it.real.timer); new_timer->it.real.timer.data = (unsigned long) new_timer; new_timer->it.real.timer.function = posix_timer_fn; - set_timer_inactive(new_timer); return 0; } @@ -480,7 +462,6 @@ static void posix_timer_fn(unsigned long int do_notify = 1; spin_lock_irqsave(&timr->it_lock, flags); - set_timer_inactive(timr); if (!list_empty(&timr->it.real.abs_timer_entry)) { spin_lock(&abs_list.lock); do { @@ -983,8 +964,8 @@ common_timer_set(struct k_itimer *timr, * careful here. If smp we could be in the "fire" routine which will * be spinning as we hold the lock. But this is ONLY an SMP issue. */ + if (try_to_del_timer_sync(&timr->it.real.timer) < 0) { #ifdef CONFIG_SMP - if (timer_active(timr) && !del_timer(&timr->it.real.timer)) /* * It can only be active if on an other cpu. Since * we have cleared the interval stuff above, it should @@ -994,11 +975,9 @@ common_timer_set(struct k_itimer *timr, * a "retry" exit status. */ return TIMER_RETRY; - - set_timer_inactive(timr); -#else - del_timer(&timr->it.real.timer); #endif + } + remove_from_abslist(timr); timr->it_requeue_pending = (timr->it_requeue_pending + 2) & @@ -1083,8 +1062,9 @@ retry: static inline int common_timer_del(struct k_itimer *timer) { timer->it.real.incr = 0; + + if (try_to_del_timer_sync(&timer->it.real.timer) < 0) { #ifdef CONFIG_SMP - if (timer_active(timer) && !del_timer(&timer->it.real.timer)) /* * It can only be active if on an other cpu. Since * we have cleared the interval stuff above, it should @@ -1094,9 +1074,9 @@ static inline int common_timer_del(struc * a "retry" exit status. */ return TIMER_RETRY; -#else - del_timer(&timer->it.real.timer); #endif + } + remove_from_abslist(timer); return 0; - 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/