Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751982Ab3FZJqj (ORCPT ); Wed, 26 Jun 2013 05:46:39 -0400 Received: from mail-ee0-f54.google.com ([74.125.83.54]:50831 "EHLO mail-ee0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751572Ab3FZJqi (ORCPT ); Wed, 26 Jun 2013 05:46:38 -0400 Date: Wed, 26 Jun 2013 11:46:34 +0200 From: Ingo Molnar To: Borislav Petkov Cc: Robert Richter , Peter Zijlstra , Arnaldo Carvalho de Melo , Jiri Olsa , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 00/14] perf, persistent: Kernel updates for perf tool integration Message-ID: <20130626094634.GA29181@gmail.com> References: <1370968960-22527-1-git-send-email-rric@kernel.org> <20130624152557.GU28407@twins.programming.kicks-ass.net> <20130624194510.GC4065@gmail.com> <20130625175729.GI21579@rric.localhost> <20130625191654.GH4855@pd.tnic> <20130626081223.GB21788@rric.localhost> <20130626082408.GA20274@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130626082408.GA20274@pd.tnic> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1053 Lines: 29 * Borislav Petkov wrote: > On Wed, Jun 26, 2013 at 10:12:23AM +0200, Robert Richter wrote: > > We get a new fd by opening the persistent event with the syscall. > > There would be 2 new ioctls: > > > > ioctl(fd, PERF_EVENT_IOC_DETACH, 0); > > ioctl(fd, PERF_EVENT_IOC_ATTACH, 0); > > > > This would be fine and reuses existing infrastructure. > > Well, how are you going to say that you want to open an already existing > persistent event or your want to create exactly the same persistent > event? Are we even going to allow identical persistent events to > coexist? If already existing persistent events show up somewhere in sysfs (or in a separate pseudofilesystem) then an open() of them [given sufficient privileges of the caller, etc.] could attach to them. Thanks, Ingo -- 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/