From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S934492AbeD0Orx (ORCPT <rfc822;w@1wt.eu>);
        Fri, 27 Apr 2018 10:47:53 -0400
Received: from mail.kernel.org ([198.145.29.99]:38412 "EHLO mail.kernel.org"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S934021AbeD0Orv (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Fri, 27 Apr 2018 10:47:51 -0400
DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 41757218D9
Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org
Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=rostedt@goodmis.org
Date: Fri, 27 Apr 2018 10:47:47 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Joel Fernandes <joelaf@google.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@redhat.com>,
        Tom Zanussi <tom.zanussi@linux.intel.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Boqun Feng <boqun.feng@gmail.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        fweisbec <fweisbec@gmail.com>, Randy Dunlap <rdunlap@infradead.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        kbuild test robot <fengguang.wu@intel.com>,
        baohong liu <baohong.liu@intel.com>,
        vedang patel <vedang.patel@intel.com>, kernel-team@android.com
Subject: Re: [PATCH RFC] tracepoint: Introduce tracepoint callbacks
 executing with preempt on
Message-ID: <20180427104747.2d965925@gandalf.local.home>
In-Reply-To: <1169911546.5820.1524839189395.JavaMail.zimbra@efficios.com>
References: <20180427042656.190746-1-joelaf@google.com>
        <1169911546.5820.1524839189395.JavaMail.zimbra@efficios.com>
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
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Fri, 27 Apr 2018 10:26:29 -0400 (EDT)
Mathieu Desnoyers <mathieu.desnoyers@efficios.com> wrote:

> The general approach and the implementation look fine, except for
> one small detail: I would be tempted to explicitly disable preemption
> around the call to the tracepoint callback for the rcuidle variant,
> unless we plan to audit every tracer right away to remove any assumption
> that preemption is disabled in the callback implementation.

I'm thinking that we do that audit. There shouldn't be many instances
of it. I like the idea that a tracepoint callback gets called with
preemption enabled.

-- Steve