Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757595AbZCTIrh (ORCPT ); Fri, 20 Mar 2009 04:47:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757382AbZCTIrU (ORCPT ); Fri, 20 Mar 2009 04:47:20 -0400 Received: from ey-out-2122.google.com ([74.125.78.27]:53544 "EHLO ey-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757038AbZCTIrR (ORCPT ); Fri, 20 Mar 2009 04:47:17 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=ww5gm3IBef32keBHX0k+ERmq5AddAUAqJKXpJlIT/ORoB+XzbiN1pNLjV8fiTMwn6e gZknAoL5gTtuJqe6bjMnt0c6mWpmq7Ycqn9+fJy06SPplU/gjlfQuBFp6vD97Lp43ID9 45ABM8Fy+LzGqG6vbopN1fZ4+k7rfhknK0pc8= Date: Fri, 20 Mar 2009 09:47:12 +0100 From: Frederic Weisbecker To: Li Zefan Cc: Ingo Molnar , Jens Axboe , Arnaldo Carvalho de Melo , Steven Rostedt , LKML Subject: Re: [PATCH 2/7] blktrace: make blk_tracer_enabled a bool flag Message-ID: <20090320084711.GA7820@nowhere> References: <49C2F599.3060306@cn.fujitsu.com> <49C2F5D3.8090104@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <49C2F5D3.8090104@cn.fujitsu.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1744 Lines: 57 On Fri, Mar 20, 2009 at 09:48:03AM +0800, Li Zefan wrote: > It doesn't have to be a counter, and it can be a bool flag instead. > > Signed-off-by: Li Zefan > --- > kernel/trace/blktrace.c | 12 +++--------- > 1 files changed, 3 insertions(+), 9 deletions(-) > > diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c > index fb3bc53..73845b7 100644 > --- a/kernel/trace/blktrace.c > +++ b/kernel/trace/blktrace.c > @@ -30,7 +30,7 @@ > static unsigned int blktrace_seq __read_mostly = 1; > > static struct trace_array *blk_tr; > -static int __read_mostly blk_tracer_enabled; > +static bool blk_tracer_enabled __read_mostly; > > /* Select an alternative, minimalistic output than the original one */ > #define TRACE_BLK_OPT_CLASSIC 0x1 > @@ -1111,9 +1111,7 @@ static int blk_tracer_init(struct trace_array *tr) > { > blk_tr = tr; > blk_tracer_start(tr); > - mutex_lock(&blk_probe_mutex); > - blk_tracer_enabled++; > - mutex_unlock(&blk_probe_mutex); > + blk_tracer_enabled = true; > return 0; > } > > @@ -1131,11 +1129,7 @@ static void blk_tracer_reset(struct trace_array *tr) > if (!atomic_read(&blk_probes_ref)) > return; > > - mutex_lock(&blk_probe_mutex); > - blk_tracer_enabled--; > - WARN_ON(blk_tracer_enabled < 0); > - mutex_unlock(&blk_probe_mutex); > - > + blk_tracer_enabled = false; > blk_tracer_stop(tr); > } > > -- > 1.5.4.rc3 Looks good. Indeed the init() and reset() callbacks are not supposed to be called nested. -- 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/