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=-7.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 1FF81C43387 for ; Wed, 19 Dec 2018 12:22:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D340D21873 for ; Wed, 19 Dec 2018 12:22:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545222151; bh=oK4WyuOXJgpyGzP1UK5yZ9WfcAbnMNWI5+yjGQxwvo4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=gx3QHLss/y+0ZqwQ++liE6ldyfbzY/FVrQIs4fN6+HXBSIBKoUUJcB8P4YiNLWcYT uxUCthO0aTH7cfziNfbl6X37lwPPwZ7GRAQ5yzoHjw8PULde1J+VzgRpcYumUOCbbK 5R52uQwgLQguRyLHqrWynLM6yof59QHweAXXD53E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728843AbeLSMWa (ORCPT ); Wed, 19 Dec 2018 07:22:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:39454 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727993AbeLSMWa (ORCPT ); Wed, 19 Dec 2018 07:22:30 -0500 Received: from devbox (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (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 25FDA217D9; Wed, 19 Dec 2018 12:22:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545222148; bh=oK4WyuOXJgpyGzP1UK5yZ9WfcAbnMNWI5+yjGQxwvo4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=eFLkOiwTKd0PGD7x2ktTs8CdDSwvzTO6Iet86nkEB/DpEnbJVcBqKciU0savVgLDO I+sEXtAtmzxpCzF/WU2GUQNldqddf/JhMESh0bLWzNTAfYh6qsERYc0rGNc33Bm/6K /YecaGBSUfyZ7LnH8WGdBVK6bKHQZSMsEQq/Kzb0= Date: Wed, 19 Dec 2018 21:22:24 +0900 From: Masami Hiramatsu To: Tom Zanussi Cc: rostedt@goodmis.org, 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 Subject: Re: [PATCH 3/7] tracing: Use var_refs[] for hist trigger reference checking Message-Id: <20181219212224.968ee0ad61aada5a8a3f634f@kernel.org> In-Reply-To: References: X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-redhat-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 Hi Tom, On Tue, 18 Dec 2018 14:33:22 -0600 Tom Zanussi wrote: > From: Tom Zanussi > > Since all the variable reference hist_fields are collected into > hist_data->var_refs[] array, there's no need to go through all the > fields looking for them, or in separate arrays like synth_var_refs[], > which will be going away soon anyway. > > This also allows us to get rid of some unnecessary code and functions > currently used for the same purpose. I just have a nitpick. > > Signed-off-by: Tom Zanussi > --- > kernel/trace/trace_events_hist.c | 57 +++++----------------------------------- > 1 file changed, 7 insertions(+), 50 deletions(-) > > diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c > index 25d06b3ae1f6..ee839c52bd3f 100644 > --- a/kernel/trace/trace_events_hist.c > +++ b/kernel/trace/trace_events_hist.c > @@ -1299,45 +1299,11 @@ check_field_for_var_ref(struct hist_field *hist_field, > { > struct hist_field *found = NULL; > > - if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF) { > - if (hist_field->var.idx == var_idx && > - hist_field->var.hist_data == var_data) { > - found = hist_field; > - } > - } > - > - return found; > -} > - > -static struct hist_field * > -check_field_for_var_refs(struct hist_trigger_data *hist_data, > - struct hist_field *hist_field, > - struct hist_trigger_data *var_data, > - unsigned int var_idx, > - unsigned int level) > -{ > - struct hist_field *found = NULL; > - unsigned int i; > - > - if (level > 3) > - return found; > - > - if (!hist_field) > - return found; > + WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); > > - found = check_field_for_var_ref(hist_field, var_data, var_idx); > - if (found) > - return found; > - > - for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { > - struct hist_field *operand; > - > - operand = hist_field->operands[i]; > - found = check_field_for_var_refs(hist_data, operand, var_data, > - var_idx, level + 1); > - if (found) > - return found; > - } > + if (hist_field && hist_field->var.idx == var_idx && > + hist_field->var.hist_data == var_data) > + found = hist_field; > > return found; It seems we don't need "found" var here. Just return hist_field or NULL. > } > @@ -1349,18 +1315,9 @@ static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, > struct hist_field *hist_field, *found = NULL; > unsigned int i; > > - for_each_hist_field(i, hist_data) { > - hist_field = hist_data->fields[i]; > - found = check_field_for_var_refs(hist_data, hist_field, > - var_data, var_idx, 0); > - if (found) > - return found; > - } > - > - for (i = 0; i < hist_data->n_synth_var_refs; i++) { > - hist_field = hist_data->synth_var_refs[i]; > - found = check_field_for_var_refs(hist_data, hist_field, > - var_data, var_idx, 0); > + for (i = 0; i < hist_data->n_var_refs; i++) { > + hist_field = hist_data->var_refs[i]; > + found = check_field_for_var_ref(hist_field, var_data, var_idx); > if (found) > return found; > } Here too. If you return soon after found it, you don't need to assign it. Except for that, it looks good to me. Reviewed-by: Masami Hiramatsu Thank you, > -- > 2.14.1 > -- Masami Hiramatsu