From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753106AbZFTFGd (ORCPT ); Sat, 20 Jun 2009 01:06:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751724AbZFTFGR (ORCPT ); Sat, 20 Jun 2009 01:06:17 -0400 Received: from ey-out-2122.google.com ([74.125.78.26]:43760 "EHLO ey-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751657AbZFTFGQ (ORCPT ); Sat, 20 Jun 2009 01:06:16 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=L585rizDyfNn3GX9spHxV+YhrCCKzubYimWFKZEQsTgW/lQcKrCVoZVEVvb7C236+s yKpY71njTPglmps5t/peOjqznzk5VaxNIx4/jn55FR1osoq+/2OBu0GlbrzAuNbTTzT7 kqc4PLudE2qae6NO09zbklo/z5zjud9ITuQ8o= From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Frederic Weisbecker , Steven Rostedt Subject: [PATCH 2/2] tracing/urgent: warn in case of ftrace_start_up inbalance Date: Sat, 20 Jun 2009 07:06:12 +0200 Message-Id: <1245474372-5249-3-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.6.2.3 In-Reply-To: <1245474372-5249-1-git-send-email-fweisbec@gmail.com> References: <1245474372-5249-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prevent from further ftrace_start_up inbalances so that we avoid future nop patching omissions with dynamic ftrace. Signed-off-by: Frederic Weisbecker Cc: Steven Rostedt --- kernel/trace/ftrace.c | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index bb60732..3718d55 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1224,6 +1224,13 @@ static void ftrace_shutdown(int command) return; ftrace_start_up--; + /* + * Just warn in case of unbalance, no need to kill ftrace, it's not + * critical but the ftrace_call callers may be never nopped again after + * further ftrace uses. + */ + WARN_ON_ONCE(ftrace_start_up < 0); + if (!ftrace_start_up) command |= FTRACE_DISABLE_CALLS; -- 1.6.2.3