Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754082AbdIEAyF (ORCPT ); Mon, 4 Sep 2017 20:54:05 -0400 Received: from mail-qk0-f175.google.com ([209.85.220.175]:38086 "EHLO mail-qk0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754055AbdIEAyE (ORCPT ); Mon, 4 Sep 2017 20:54:04 -0400 X-Google-Smtp-Source: ADKCNb65P6Vx9PeAg7wPmG2UnHFoismJtdkb8KfV9fABtTOuVnJEbtnG7T9lmDAjIoWkQBrQtziNX2rREqn5jK9hrKg= MIME-Version: 1.0 In-Reply-To: <20170904193436.4a37fae4@gandalf.local.home> References: <20170903085051.6348-1-joelaf@google.com> <20170903085051.6348-3-joelaf@google.com> <20170904075614.bjkkrgyv2dpz7x5v@hirez.programming.kicks-ass.net> <20170904194426.GD17526@worktop.programming.kicks-ass.net> <20170904193436.4a37fae4@gandalf.local.home> From: Joel Fernandes Date: Mon, 4 Sep 2017 17:54:02 -0700 Message-ID: Subject: Re: [PATCH 2/2] tracing: Add support for critical section events To: Steven Rostedt Cc: Peter Zijlstra , LKML , kernel-team@android.com, Ingo Molnar , Byungchul Park , Tejun Heo Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1797 Lines: 51 On Mon, Sep 4, 2017 at 4:34 PM, Steven Rostedt wrote: > On Mon, 4 Sep 2017 21:44:26 +0200 > Peter Zijlstra wrote: > >> > I can change the name to something else, but at the moment I can't >> > think of anything better. Could you suggest a better name? Also btw, >> > 'critical timings' is the terminology used within the irqsoff tracer >> > so this is in line with that. >> >> So 'critical section' is what some mis-guided people call the locked >> region of a lock :-) Using it for something else is prone to cause more >> confusion... >> >> I would simply call them what they are: irq_disable,irq_enable >> preempt_disable,preempt_enable. > > Yes please. The "critical section" naming came from the code that was > from the latency tracer days of the real time patch (pre-ftrace). The > irqsoff tracer has the least modification from the original code, and > probably should be rewritten one of these days. Sounds good to me. For the subsystem, could you guys suggest a name? I was thinking "atomic_section"? Something like: subsystem: atomic_section events: irqsoff_disable irqsoff_enable preemptoff_disable preemptoff_enable and additionally (to do what my patch does): preemptirqsoff_enable preemptirqsoff_disable Does this sound good to you? I did bulk of the work today for moving code from the irqsoff tracer into a common area that's irqsoff tracer specific, and now I'm getting close to the point of creating the above tracepoints and posting another series, but I wanted to get your thoughts on the above. I like this new approach better because the next logically step ontop of this work can be to rewrite irqsoff tracer by using probes on the above tracepoints (which I'll do once we can get these in). thanks, - Joel