From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751330AbdJDSNC (ORCPT ); Wed, 4 Oct 2017 14:13:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:51468 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750797AbdJDSNB (ORCPT ); Wed, 4 Oct 2017 14:13:01 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 50B192188D 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: Wed, 4 Oct 2017 14:12:57 -0400 From: Steven Rostedt To: Tom Zanussi Cc: tglx@linutronix.de, mhiramat@kernel.org, namhyung@kernel.org, vedang.patel@intel.com, bigeasy@linutronix.de, joel.opensrc@gmail.com, joelaf@google.com, mathieu.desnoyers@efficios.com, baohong.liu@intel.com, rajvi.jingar@intel.com, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Subject: Re: [PATCH v3 26/33] tracing: Add cpu field for hist triggers Message-ID: <20171004141257.5ce2a214@gandalf.local.home> In-Reply-To: References: X-Mailer: Claws Mail 3.14.0 (GTK+ 2.24.31; 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: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 22 Sep 2017 15:00:06 -0500 Tom Zanussi wrote: > A common key to use in a histogram is the cpuid - add a new cpu > 'synthetic' field for that purpose. This field is named cpu rather > than $cpu or $common_cpu because 'cpu' already exists as a special > filter field and it makes more sense to match that rather than add > another name for the same thing. > > Signed-off-by: Tom Zanussi > --- > Documentation/trace/events.txt | 18 ++++++++++++++++++ > kernel/trace/trace_events_hist.c | 28 +++++++++++++++++++++++++++- > 2 files changed, 45 insertions(+), 1 deletion(-) > > diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt > index 2cc08d4..f36fa00 100644 > --- a/Documentation/trace/events.txt > +++ b/Documentation/trace/events.txt > @@ -668,6 +668,24 @@ The following commands are supported: > The examples below provide a more concrete illustration of the > concepts and typical usage patterns discussed above. > > + 'special' event fields > + ------------------------ > + > + There are a number of 'special event fields' available for use as > + keys or values in a hist trigger. These look like and behave as if > + they were actual event fields, but aren't really part of the event's > + field definition or format file. They are however available for any > + event, and can be used anywhere an actual event field could be. > + 'Special' field names are always prefixed with a '$' character to > + indicate that they're not normal fields (with the exception of > + 'cpu', for compatibility with existing filter usage): > + > + $common_timestamp u64 - timestamp (from ring buffer) associated > + with the event, in nanoseconds. May be > + modified by .usecs to have timestamps > + interpreted as microseconds. > + cpu int - the cpu on which the event occurred. > + > You were going to update this too. -- Steve