From patchwork Thu Jan 8 10:03:27 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 426555 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id BA9FD14009B for ; Thu, 8 Jan 2015 21:06:40 +1100 (AEDT) Received: from localhost ([::1]:45201 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y99zC-0000b1-IQ for incoming@patchwork.ozlabs.org; Thu, 08 Jan 2015 05:06:38 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37110) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y99wT-0004AP-JC for qemu-devel@nongnu.org; Thu, 08 Jan 2015 05:03:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Y99wK-0002Sj-4L for qemu-devel@nongnu.org; Thu, 08 Jan 2015 05:03:49 -0500 Received: from mail-we0-x231.google.com ([2a00:1450:400c:c03::231]:40123) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y99wJ-0002Rc-UA for qemu-devel@nongnu.org; Thu, 08 Jan 2015 05:03:40 -0500 Received: by mail-we0-f177.google.com with SMTP id q59so1562454wes.8 for ; Thu, 08 Jan 2015 02:03:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:subject:date:message-id:in-reply-to:references; bh=+xD2IFjDDab7k4aLMd8aLGDFQNXlaTxp0bXzqC4gy2Y=; b=PXqdnoz0CyucqoaZ1Slgic4n98kf0Mauh6S+wJx2IyXM6dyvBVY9WrsGFjfpWbcHMN tnFS5rkM6p6qPXhpvbhq6zdQZ5QdOtmIGvGxYjxfzaQ0Ubo0k5IrZzLKjOdue4OQKASb CgOFvl6WU+CFp6cx95xIwBLE4qg2RPekEVdsdwKDrMNzDGVFa9x51MG19W7P0f2ueEOS hvC5e4Wu9jk3DoCFp9uytaWStH23SDR4Py9QpWP/e4PeOSImxw4ljNRGD3fWYYInEdll BBYXm2+2P8WRuWB3baqAW3lUIHFVbXKKSy/HRa1UcnqU5b9G33nVIJUr14XGXfu2aVPR rUEw== X-Received: by 10.180.97.196 with SMTP id ec4mr17474172wib.71.1420711419346; Thu, 08 Jan 2015 02:03:39 -0800 (PST) Received: from playground.station (net-37-117-147-67.cust.vodafonedsl.it. [37.117.147.67]) by mx.google.com with ESMTPSA id qg11sm21175327wic.17.2015.01.08.02.03.37 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 08 Jan 2015 02:03:38 -0800 (PST) From: Paolo Bonzini To: qemu-devel@nongnu.org Date: Thu, 8 Jan 2015 11:03:27 +0100 Message-Id: <1420711408-15766-4-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1420711408-15766-1-git-send-email-pbonzini@redhat.com> References: <1420711408-15766-1-git-send-email-pbonzini@redhat.com> X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2a00:1450:400c:c03::231 Subject: [Qemu-devel] [PATCH 3/4] qemu-timer: introduce timer_deinit X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org In some cases, a timer was set to NULL so that we could check if it is initialized. Use the timer_list field instead, and add a timer_deinit function that NULLs it. It then makes sense that timer_del be a no-op (instead of a crasher) on such a de-initialized timer. It avoids the need to poke at the timerlist field to check if the timers are initialized. Signed-off-by: Paolo Bonzini --- include/qemu/timer.h | 11 +++++++++++ qemu-timer.c | 14 +++++++++++--- 2 files changed, 22 insertions(+), 3 deletions(-) diff --git a/include/qemu/timer.h b/include/qemu/timer.h index 9f44233..5d5802f 100644 --- a/include/qemu/timer.h +++ b/include/qemu/timer.h @@ -595,6 +595,17 @@ static inline QEMUTimer *timer_new_ms(QEMUClockType type, QEMUTimerCB *cb, } /** + * timer_deinit: + * @ts: the timer to be de-initialised + * + * Deassociate the timer from any timerlist. You should + * call timer_del before. After this call, any further + * timer_del call cannot cause dangling pointer accesses + * even if the previously used timerlist is freed. + */ +void timer_deinit(QEMUTimer *ts); + +/** * timer_free: * @ts: the timer * diff --git a/qemu-timer.c b/qemu-timer.c index 98d9d1b..464396f 100644 --- a/qemu-timer.c +++ b/qemu-timer.c @@ -342,6 +342,12 @@ void timer_init_tl(QEMUTimer *ts, ts->expire_time = -1; } +void timer_deinit(QEMUTimer *ts) +{ + assert(ts->expire_time == -1); + ts->timer_list = NULL; +} + void timer_free(QEMUTimer *ts) { g_free(ts); @@ -398,9 +404,11 @@ void timer_del(QEMUTimer *ts) { QEMUTimerList *timer_list = ts->timer_list; - qemu_mutex_lock(&timer_list->active_timers_lock); - timer_del_locked(timer_list, ts); - qemu_mutex_unlock(&timer_list->active_timers_lock); + if (timer_list) { + qemu_mutex_lock(&timer_list->active_timers_lock); + timer_del_locked(timer_list, ts); + qemu_mutex_unlock(&timer_list->active_timers_lock); + } } /* modify the current timer so that it will be fired when current_time