Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753359AbdIDH4W (ORCPT ); Mon, 4 Sep 2017 03:56:22 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:59873 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751949AbdIDH4V (ORCPT ); Mon, 4 Sep 2017 03:56:21 -0400 Date: Mon, 4 Sep 2017 09:56:14 +0200 From: Peter Zijlstra To: Joel Fernandes Cc: linux-kernel@vger.kernel.org, Steven Rostedt , kernel-team@android.com, Ingo Molnar , Byungchul Park , Tejun Heo Subject: Re: [PATCH 2/2] tracing: Add support for critical section events Message-ID: <20170904075614.bjkkrgyv2dpz7x5v@hirez.programming.kicks-ass.net> References: <20170903085051.6348-1-joelaf@google.com> <20170903085051.6348-3-joelaf@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170903085051.6348-3-joelaf@google.com> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 656 Lines: 13 On Sun, Sep 03, 2017 at 01:50:51AM -0700, Joel Fernandes wrote: > Critical section trace events can be used for tracing the start and > end of a critical section which can be used by a trace viewer like > systrace to graphically view the start and end of a critical section and > correlate them with latencies and scheduling issues. > > Reason for starting critical section: > Either preemption or interrupts were turned off. > Reason for ending critical section: > Both preemption and interrupts are now turned back on. Please don't use the name critical section for this. Also IRQ and preempt already have a gazillion trace hooks, why do we need more?