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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 F2135C43387 for ; Sat, 22 Dec 2018 18:01:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC38A218FD for ; Sat, 22 Dec 2018 18:01:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388336AbeLVSBM (ORCPT ); Sat, 22 Dec 2018 13:01:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:39018 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732686AbeLVSBM (ORCPT ); Sat, 22 Dec 2018 13:01:12 -0500 Received: from gandalf.local.home (cpe-66-24-56-78.stny.res.rr.com [66.24.56.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C5C892080D; Sat, 22 Dec 2018 18:01:09 +0000 (UTC) Date: Sat, 22 Dec 2018 13:01:07 -0500 From: Steven Rostedt To: Tom Zanussi Cc: linux-kernel@vger.kernel.org, Ingo Molnar , Andrew Morton , Joe Perches , Namhyung Kim , Linus Torvalds , Yoshinori Sato , Rich Felker , linux-sh@vger.kernel.org Subject: Re: [for-next][PATCH 2/5] tracing: Use str_has_prefix() helper for histogram code Message-ID: <20181222130107.43aaac9c@gandalf.local.home> In-Reply-To: <20181222162856.666843139@goodmis.org> References: <20181222162007.697862256@goodmis.org> <20181222162856.666843139@goodmis.org> X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 22 Dec 2018 11:20:09 -0500 Steven Rostedt wrote: > From: "Steven Rostedt (VMware)" > > The tracing histogram code contains a lot of instances of the construct: > > strncmp(str, "const", sizeof("const") - 1) > > This can be prone to bugs due to typos or bad cut and paste. Use the > str_has_prefix() helper macro instead that removes the need for having two > copies of the constant string. > > Cc: Tom Zanussi I have no idea why I copied your intel email. The linux.intel.com appears to be no longer active. I'm going to rebase to fix this email address. -- Steve > Signed-off-by: Steven Rostedt (VMware) > --- > kernel/trace/trace_events_hist.c | 28 ++++++++++++++-------------- > 1 file changed, 14 insertions(+), 14 deletions(-) > > diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c > index c5448c103770..9d590138f870 100644 > --- a/kernel/trace/trace_events_hist.c > +++ b/kernel/trace/trace_events_hist.c > @@ -1881,8 +1881,8 @@ static int parse_action(char *str, struct hist_trigger_attrs *attrs) > if (attrs->n_actions >= HIST_ACTIONS_MAX) > return ret; > > - if ((strncmp(str, "onmatch(", sizeof("onmatch(") - 1) == 0) || > - (strncmp(str, "onmax(", sizeof("onmax(") - 1) == 0)) { > + if ((str_has_prefix(str, "onmatch(")) || > + (str_has_prefix(str, "onmax("))) { > attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); > if (!attrs->action_str[attrs->n_actions]) { > ret = -ENOMEM; > @@ -1899,34 +1899,34 @@ static int parse_assignment(char *str, struct hist_trigger_attrs *attrs) > { > int ret = 0; > > - if ((strncmp(str, "key=", sizeof("key=") - 1) == 0) || > - (strncmp(str, "keys=", sizeof("keys=") - 1) == 0)) { > + if ((str_has_prefix(str, "key=")) || > + (str_has_prefix(str, "keys="))) { > attrs->keys_str = kstrdup(str, GFP_KERNEL); > if (!attrs->keys_str) { > ret = -ENOMEM; > goto out; > } > - } else if ((strncmp(str, "val=", sizeof("val=") - 1) == 0) || > - (strncmp(str, "vals=", sizeof("vals=") - 1) == 0) || > - (strncmp(str, "values=", sizeof("values=") - 1) == 0)) { > + } else if ((str_has_prefix(str, "val=")) || > + (str_has_prefix(str, "vals=")) || > + (str_has_prefix(str, "values="))) { > attrs->vals_str = kstrdup(str, GFP_KERNEL); > if (!attrs->vals_str) { > ret = -ENOMEM; > goto out; > } > - } else if (strncmp(str, "sort=", sizeof("sort=") - 1) == 0) { > + } else if (str_has_prefix(str, "sort=")) { > attrs->sort_key_str = kstrdup(str, GFP_KERNEL); > if (!attrs->sort_key_str) { > ret = -ENOMEM; > goto out; > } > - } else if (strncmp(str, "name=", sizeof("name=") - 1) == 0) { > + } else if (str_has_prefix(str, "name=")) { > attrs->name = kstrdup(str, GFP_KERNEL); > if (!attrs->name) { > ret = -ENOMEM; > goto out; > } > - } else if (strncmp(str, "clock=", sizeof("clock=") - 1) == 0) { > + } else if (str_has_prefix(str, "clock=")) { > strsep(&str, "="); > if (!str) { > ret = -EINVAL; > @@ -1939,7 +1939,7 @@ static int parse_assignment(char *str, struct hist_trigger_attrs *attrs) > ret = -ENOMEM; > goto out; > } > - } else if (strncmp(str, "size=", sizeof("size=") - 1) == 0) { > + } else if (str_has_prefix(str, "size=")) { > int map_bits = parse_map_size(str); > > if (map_bits < 0) { > @@ -3558,7 +3558,7 @@ static struct action_data *onmax_parse(char *str) > if (!onmax_fn_name || !str) > goto free; > > - if (strncmp(onmax_fn_name, "save", sizeof("save") - 1) == 0) { > + if (str_has_prefix(onmax_fn_name, "save")) { > char *params = strsep(&str, ")"); > > if (!params) { > @@ -4346,7 +4346,7 @@ static int parse_actions(struct hist_trigger_data *hist_data) > for (i = 0; i < hist_data->attrs->n_actions; i++) { > str = hist_data->attrs->action_str[i]; > > - if (strncmp(str, "onmatch(", sizeof("onmatch(") - 1) == 0) { > + if (str_has_prefix(str, "onmatch(")) { > char *action_str = str + sizeof("onmatch(") - 1; > > data = onmatch_parse(tr, action_str); > @@ -4355,7 +4355,7 @@ static int parse_actions(struct hist_trigger_data *hist_data) > break; > } > data->fn = action_trace; > - } else if (strncmp(str, "onmax(", sizeof("onmax(") - 1) == 0) { > + } else if (str_has_prefix(str, "onmax(")) { > char *action_str = str + sizeof("onmax(") - 1; > > data = onmax_parse(action_str);