Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754552Ab1DZK6T (ORCPT ); Tue, 26 Apr 2011 06:58:19 -0400 Received: from casper.infradead.org ([85.118.1.10]:40889 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754487Ab1DZK6R convert rfc822-to-8bit (ORCPT ); Tue, 26 Apr 2011 06:58:17 -0400 Subject: Re: [PATCH 02/18] perf: Add persistent event facilities From: Peter Zijlstra To: Borislav Petkov Cc: Arnaldo Carvalho de Melo , Ingo Molnar , Steven Rostedt , Frederic Weisbecker , Tony Luck , Mauro Carvalho Chehab , David Ahern , EDAC devel , LKML , Borislav Petkov In-Reply-To: <1303576100-425-3-git-send-email-bp@amd64.org> References: <1303576100-425-1-git-send-email-bp@amd64.org> <1303576100-425-3-git-send-email-bp@amd64.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Tue, 26 Apr 2011 12:57:50 +0200 Message-ID: <1303815470.20212.260.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1707 Lines: 38 On Sat, 2011-04-23 at 18:28 +0200, Borislav Petkov wrote: > From: Borislav Petkov > > Add a barebones implementation for registering persistent events with > perf. For that, we don't destroy the buffers when they're unmapped and > we map them read-only so that multiple agents can access them. > > Signed-off-by: Borislav Petkov > --- > include/linux/perf_event.h | 22 ++++++++++++++++- > kernel/events/Makefile | 2 +- > kernel/events/core.c | 30 ++++++++++++++++++---- > kernel/events/persistent.c | 56 ++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 102 insertions(+), 8 deletions(-) > create mode 100644 kernel/events/persistent.c > > diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h > index ee9f1e7..37bfae1 100644 > --- a/include/linux/perf_event.h > +++ b/include/linux/perf_event.h > @@ -216,8 +216,9 @@ struct perf_event_attr { > precise_ip : 2, /* skid constraint */ > mmap_data : 1, /* non-exec mmap data */ > sample_id_all : 1, /* sample_type all events */ > + persistent : 1, /* event always on */ But how will you find it again? Persistent yells filesystem to me, and while we didn't use relayfs for various reasons, I think we do need something like it at the current stage. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/