From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3986C43387 for ; Wed, 16 Jan 2019 04:59:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96F1B20840 for ; Wed, 16 Jan 2019 04:59:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732221AbfAPE7V (ORCPT ); Tue, 15 Jan 2019 23:59:21 -0500 Received: from smtprelay0192.hostedemail.com ([216.40.44.192]:60332 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728034AbfAPE7V (ORCPT ); Tue, 15 Jan 2019 23:59:21 -0500 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay05.hostedemail.com (Postfix) with ESMTP id 1631718045A60; Wed, 16 Jan 2019 04:59:20 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: train58_6e54b26c3325c X-Filterd-Recvd-Size: 1964 Received: from XPS-9350.home (unknown [47.151.153.53]) (Authenticated sender: joe@perches.com) by omf03.hostedemail.com (Postfix) with ESMTPA; Wed, 16 Jan 2019 04:59:18 +0000 (UTC) Message-ID: <7c07519607d08c0afe448a03fb2010bce13cd77f.camel@perches.com> Subject: Re: [PATCH v12 01/16] tracing: Use str_has_prefix() in synth_event_create() From: Joe Perches To: Tom Zanussi , rostedt@goodmis.org Cc: tglx@linutronix.de, mhiramat@kernel.org, namhyung@kernel.org, vedang.patel@intel.com, bigeasy@linutronix.de, joel@joelfernandes.org, mathieu.desnoyers@efficios.com, julia@ni.com, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Date: Tue, 15 Jan 2019 20:59:16 -0800 In-Reply-To: References: Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.30.1-1build1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2019-01-15 at 16:05 -0600, Tom Zanussi wrote: > Since we now have a str_has_prefix() that returns the length, we can > use that instead of explicitly calculating it. [] > diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c [] > @@ -1200,8 +1200,7 @@ static int synth_event_create(int argc, const char **argv) > > /* This interface accepts group name prefix */ > if (strchr(name, '/')) { > - len = sizeof(SYNTH_SYSTEM "/") - 1; > - if (strncmp(name, SYNTH_SYSTEM "/", len)) > + if ((len = str_has_prefix(name, SYNTH_SYSTEM "/")) == 0) Since this is a single test, and not multiple if/else if blocks, I believe this would read better on two lines len = str_has_prefix(name, SYNTH_SYSTEM "/"); if (len == 0) > return -EINVAL; > name += len; > }