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=-8.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_2 autolearn=unavailable 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 AC245C433EC for ; Mon, 27 Jul 2020 18:46:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 904A82075A for ; Mon, 27 Jul 2020 18:46:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732286AbgG0Sqg (ORCPT ); Mon, 27 Jul 2020 14:46:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:35542 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732095AbgG0Spw (ORCPT ); Mon, 27 Jul 2020 14:45:52 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 BB38E2075A; Mon, 27 Jul 2020 18:45:51 +0000 (UTC) Date: Mon, 27 Jul 2020 14:45:50 -0400 From: Steven Rostedt To: Tingwei Zhang Cc: Ingo Molnar , tsoni@codeaurora.org, Sai Prakash Ranjan , Mao Jinlong , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/6] tracing: add flag to control different traces Message-ID: <20200727144550.7aa40c61@oasis.local.home> In-Reply-To: <20200726025931.30510-3-tingwei@codeaurora.org> References: <20200726025931.30510-1-tingwei@codeaurora.org> <20200726025931.30510-3-tingwei@codeaurora.org> X-Mailer: Claws Mail 3.17.3 (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 Sun, 26 Jul 2020 10:59:27 +0800 Tingwei Zhang wrote: > diff --git a/include/linux/trace.h b/include/linux/trace.h > index 7fd86d3c691f..d2fdf9be84b5 100644 > --- a/include/linux/trace.h > +++ b/include/linux/trace.h > @@ -3,6 +3,9 @@ > #define _LINUX_TRACE_H > > #ifdef CONFIG_TRACING > + > +#define TRACE_EXPORT_FUNCTION BIT_ULL(0) All the flags variables below are defined as "int". Why the BIT_ULL()? BIT(0) should work just fine. The ULL makes one think these flags will be used for unsigned long variables, which it is not. -- Steve > + > struct trace_export { > struct trace_export __rcu *next; > void (*write)(struct trace_export *, const void *, unsigned int); > + int flags; > }; > > int register_ftrace_export(struct trace_export *export); > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index bb62269724d5..8f1e66831e9e 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -2747,33 +2747,37 @@ trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, > > static void > trace_process_export(struct trace_export *export, > - struct ring_buffer_event *event) > + struct ring_buffer_event *event, int flag) > { > struct trace_entry *entry; > unsigned int size = 0; > > - entry = ring_buffer_event_data(event); > - size = ring_buffer_event_length(event); > - export->write(export, entry, size); > + if (export->flags & flag) { > + entry = ring_buffer_event_data(event); > + size = ring_buffer_event_length(event); > + export->write(export, entry, size); > + } > }