Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752392AbZFIEef (ORCPT ); Tue, 9 Jun 2009 00:34:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751319AbZFIEe0 (ORCPT ); Tue, 9 Jun 2009 00:34:26 -0400 Received: from bilbo.ozlabs.org ([203.10.76.25]:57039 "EHLO bilbo.ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751238AbZFIEe0 (ORCPT ); Tue, 9 Jun 2009 00:34:26 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <18989.57919.895309.847520@drongo.ozlabs.ibm.com> Date: Tue, 9 Jun 2009 14:17:03 +1000 From: Paul Mackerras To: Peter Zijlstra Cc: Ingo Molnar , Arnaldo Carvalho de Melo , Thomas Gleixner , Corey Ashford , linux-kernel Subject: Re: [PATCH] perf_counter: extensible perf_counter_attr In-Reply-To: <1244481941.13761.9119.camel@twins> References: <1244481941.13761.9119.camel@twins> X-Mailer: VM 8.0.12 under 22.3.1 (powerpc-unknown-linux-gnu) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 835 Lines: 27 Peter Zijlstra writes: > Allow extending the perf_counter_attr structure by linking extended > structures to it. ... > @@ -175,6 +175,13 @@ struct perf_counter_attr { > __u32 __reserved_3; > > __u64 __reserved_4; > + > + struct perf_counter_attr_ext *ext_attrs; > +}; Since this is a user-visible structure, you've just introduced an ABI difference between 32-bit and 64-bit processes, which we've managed to avoid so far. Assuming that is that you intend eventually to use the value that userspace puts there, which you don't at the moment. Was that your intention? Paul. -- 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/