From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755628Ab2EHOTX (ORCPT ); Tue, 8 May 2012 10:19:23 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:26623 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755220Ab2EHOTW (ORCPT ); Tue, 8 May 2012 10:19:22 -0400 X-Authority-Analysis: v=2.0 cv=cssZYiEi c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=XQbtiDEiEegA:10 a=DP5z0Fm-GvoA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=20KFwNOVAAAA:8 a=wmoV8Ok_AAAA:8 a=mPfFzUqFSPvdVt5yyicA:9 a=DRrjbNz6F0GHnCdge9UA:7 a=PUjeQqilurYA:10 a=GeWVzuwf79YA:10 a=jEp0ucaQiEUA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-ID: <1336486760.14207.176.camel@gandalf.stny.rr.com> Subject: Re: [PATCH 3/4] ftrace: No return value for ftrace_process_locs From: Steven Rostedt To: Jiri Olsa Cc: fweisbec@gmail.com, mingo@redhat.com, linux-kernel@vger.kernel.org Date: Tue, 08 May 2012 10:19:20 -0400 In-Reply-To: <1335342219-2782-4-git-send-email-jolsa@redhat.com> References: <1335342219-2782-1-git-send-email-jolsa@redhat.com> <1335342219-2782-4-git-send-email-jolsa@redhat.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.2.2-1 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2012-04-25 at 10:23 +0200, Jiri Olsa wrote: > The return value of ftrace_process_locs is never checked. The function > tries to update as many calls as possible and in case of error there's > either warning output or ftrace_bug call. > > Signed-off-by: Jiri Olsa > --- > kernel/trace/ftrace.c | 37 ++++++++++++++++--------------------- > 1 files changed, 16 insertions(+), 21 deletions(-) > > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index b3ceecd..e67f5b3 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -1930,7 +1930,7 @@ static int ops_traces_mod(struct ftrace_ops *ops) > return ftrace_hash_empty(hash); > } > > -static int ftrace_update_code(struct module *mod) > +static void ftrace_update_code(struct module *mod) > { > struct ftrace_page *pg; > struct dyn_ftrace *p; > @@ -1959,7 +1959,7 @@ static int ftrace_update_code(struct module *mod) > for (i = 0; i < pg->index; i++) { > /* If something went wrong, bail without enabling anything */ > if (unlikely(ftrace_disabled)) > - return -1; > + return; > > p = &pg->records[i]; > p->flags = ref; > @@ -1968,8 +1968,8 @@ static int ftrace_update_code(struct module *mod) > * Do the initial record conversion from mcount jump > * to the NOP instructions. > */ > - if (!ftrace_code_disable(mod, p)) > - break; > + if (WARN_ON_ONCE(!ftrace_code_disable(mod, p))) > + return; Why the warning? If ftrace_disabled is set, something broke a long time ago, and the ftrace_bug gives its own warning. I don't think this is needed. -- Steve