From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1035199AbcIWP1l (ORCPT ); Fri, 23 Sep 2016 11:27:41 -0400 Received: from merlin.infradead.org ([205.233.59.134]:49918 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966209AbcIWP1k (ORCPT ); Fri, 23 Sep 2016 11:27:40 -0400 Date: Fri, 23 Sep 2016 17:27:37 +0200 From: Peter Zijlstra To: Alexander Shishkin Cc: Ingo Molnar , linux-kernel@vger.kernel.org, vince@deater.net, eranian@google.com, Arnaldo Carvalho de Melo , tglx@linutronix.de, ak@linux.intel.com Subject: Re: [RFC PATCH 1/6] perf: Move mlock accounting to ring buffer allocation Message-ID: <20160923152737.GN5008@twins.programming.kicks-ass.net> References: <20160923112726.5890-1-alexander.shishkin@linux.intel.com> <20160923112726.5890-2-alexander.shishkin@linux.intel.com> <20160923121403.GC5012@twins.programming.kicks-ass.net> <8737kqu1x1.fsf@ashishki-desk.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8737kqu1x1.fsf@ashishki-desk.ger.corp.intel.com> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 23, 2016 at 05:27:22PM +0300, Alexander Shishkin wrote: > > Afaict there's no actual need to hide the AUX buffer for this sampling > > stuff; the user knows about all this and can simply mmap() the AUX part. > > Yes, you're right here. We could also re-use the AUX record, adding a > new flag for this. It may be even better if I can work out the > inheritance (the current code doesn't handle inheritance at the moment > in case we decide to scrap it). What is the exact problem with inheritance? You can inherit PT (and other) events just fine, and their output redirects to the original (AUX) buffer too. Is the problem untangling which part of the AUX buffer belongs to which task upon sample?