Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757432AbcJQGqX (ORCPT ); Mon, 17 Oct 2016 02:46:23 -0400 Received: from mail-lf0-f67.google.com ([209.85.215.67]:34291 "EHLO mail-lf0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752517AbcJQGqO (ORCPT ); Mon, 17 Oct 2016 02:46:14 -0400 Subject: Re: [patch] perf_event_open.2: PERF_RECORD_LOST_SAMPLES record type To: Vince Weaver References: Cc: mtk.manpages@gmail.com, linux-man@vger.kernel.org, linux-kernel@vger.kernel.org, Kan Liang , Peter Zijlstra , Ingo Molnar , Stephane Eranian From: "Michael Kerrisk (man-pages)" Message-ID: <46a73e4c-1f0f-e14c-391c-e865f52ff9be@gmail.com> Date: Mon, 17 Oct 2016 08:46:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1306 Lines: 55 Hello Vince, On 10/16/2016 04:02 AM, Vince Weaver wrote: > > Linux 4.2 added a new record type: PERF_RECORD_LOST_SAMPLES > It is generated when hardware samples (currently only Intel PEBS) > are lost. Thanks! Applied! Cheers, Michael > Signed-off-by: Vince Weaver > > diff --git a/man2/perf_event_open.2 b/man2/perf_event_open.2 > index 9f33122..a47df2d 100644 > --- a/man2/perf_event_open.2 > +++ b/man2/perf_event_open.2 > @@ -2551,6 +2551,25 @@ process ID of the thread starting an instruction trace. > .I tid > thread ID of the thread starting an instruction trace. > .RE > +.TP > +.BR PERF_RECORD_LOST_SAMPLES " (since Linux 4.2)" > +\" f38b0dbb491a6987e198aa6b428db8692a6480f8 > +When using hardware sampling (such as Intel PEBS) this record > +indicates some number of samples may have been lost. > + > +.in +4n > +.nf > +struct { > + struct perf_event_header header; > + u64 lost; > + struct sample_id sample_id; > +}; > +.fi > +.RS > +.TP > +.I lost > +the number of potentially lost samples. > +.RE > .RE > .SS Overflow handling > Events can be set to notify when a threshold is crossed, > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/