Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933008Ab2JWKLw (ORCPT ); Tue, 23 Oct 2012 06:11:52 -0400 Received: from casper.infradead.org ([85.118.1.10]:39464 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932948Ab2JWKLu convert rfc822-to-8bit (ORCPT ); Tue, 23 Oct 2012 06:11:50 -0400 Message-ID: <1350987096.2768.108.camel@twins> Subject: Re: [PATCH 1/6] perf, x86: Basic Haswell LBR call stack support From: Peter Zijlstra To: "Yan, Zheng" Cc: linux-kernel@vger.kernel.org, eranian@google.com, ak@linux.intel.com Date: Tue, 23 Oct 2012 12:11:36 +0200 In-Reply-To: <50862E02.6020002@intel.com> References: <1350886279-6141-1-git-send-email-zheng.z.yan@intel.com> <1350886279-6141-2-git-send-email-zheng.z.yan@intel.com> <1350902138.2768.86.camel@twins> <50862E02.6020002@intel.com> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Mailer: Evolution 3.2.2- Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1433 Lines: 29 On Tue, 2012-10-23 at 13:41 +0800, Yan, Zheng wrote: > On 10/22/2012 06:35 PM, Peter Zijlstra wrote: > > On Mon, 2012-10-22 at 14:11 +0800, Yan, Zheng wrote: > >> --- a/include/uapi/linux/perf_event.h > >> +++ b/include/uapi/linux/perf_event.h > >> @@ -160,8 +160,9 @@ enum perf_branch_sample_type { > >> PERF_SAMPLE_BRANCH_ABORT = 1U << 7, /* transaction aborts */ > >> PERF_SAMPLE_BRANCH_INTX = 1U << 8, /* in transaction (flag) */ > >> PERF_SAMPLE_BRANCH_NOTX = 1U << 9, /* not in transaction (flag) */ > >> + PERF_SAMPLE_BRANCH_CALL_STACK = 1U << 10, /* call stack */ > >> > >> - PERF_SAMPLE_BRANCH_MAX = 1U << 10, /* non-ABI */ > >> + PERF_SAMPLE_BRANCH_MAX = 1U << 11, /* non-ABI */ > >> }; > > > > You add an ABI sample type without mentioning it in your changelog.. I > > think I'll stop reading here. > > > Ok, I will add the ABI change to the change log. Do you think we should hide this > branch sample type from user? Possibly not, I haven't really thought about it. But never hide an ABI change. Explicitly mention it and preferably explain why you felt it needed to extend the ABI. -- 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/