Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754637Ab3GCHzu (ORCPT ); Wed, 3 Jul 2013 03:55:50 -0400 Received: from merlin.infradead.org ([205.233.59.134]:32798 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753460Ab3GCHzt (ORCPT ); Wed, 3 Jul 2013 03:55:49 -0400 Date: Wed, 3 Jul 2013 09:55:42 +0200 From: Peter Zijlstra To: Linus Torvalds Cc: Ingo Molnar , Suravee Suthikulpanit , Linux Kernel Mailing List , Arnaldo Carvalho de Melo , Thomas Gleixner , Andrew Morton Subject: Re: [GIT PULL] perf changes for v3.11 Message-ID: <20130703075542.GF23916@twins.programming.kicks-ass.net> References: <20130701090356.GA14912@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2363 Lines: 64 On Tue, Jul 02, 2013 at 05:50:29PM -0700, Linus Torvalds wrote: > On Mon, Jul 1, 2013 at 2:03 AM, Ingo Molnar wrote: > > > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-core-for-linus > > > > Kernel improvements: > > > > * AMD IOMMU uncore PMU support by Suravee Suthikulpanit001a > > This one prints a really annoying error message if you're not on an > AMD platform: > > + if (!amd_iommu_pc_supported()) { > + pr_err("perf: amd_iommu PMU not installed. No support!\n"); > + return -ENODEV; > + } > > and you know what? That's not acceptable. It damn well is *not* an > error to not have an AMD IOMMU. > > It should - at most - be a pr_info(). Maybe nothing at all. "pr_err()" > is just totally out of line. Quite; it prints enough stuff when it does find one so I'm all for scrapping that one print when it doesn't find it. Sorry for not seeing that; when I initially read that code I thought it was for the case where the hardware was expected to have the device but we couldn't find it for some weird reason. --- Subject: perf, amd: Do not print an error when the device is not present As Linus said its not an error to not have an AMD IOMMU; esp. when you're not even running on an AMD platform. Requested-by: Linus Torvalds Signed-off-by: Peter Zijlstra --- arch/x86/kernel/cpu/perf_event_amd_iommu.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_amd_iommu.c b/arch/x86/kernel/cpu/perf_event_amd_iommu.c index 0db655e..639d128 100644 --- a/arch/x86/kernel/cpu/perf_event_amd_iommu.c +++ b/arch/x86/kernel/cpu/perf_event_amd_iommu.c @@ -491,10 +491,8 @@ static struct perf_amd_iommu __perf_iommu = { static __init int amd_iommu_pc_init(void) { /* Make sure the IOMMU PC resource is available */ - if (!amd_iommu_pc_supported()) { - pr_err("perf: amd_iommu PMU not installed. No support!\n"); + if (!amd_iommu_pc_supported()) return -ENODEV; - } _init_perf_amd_iommu(&__perf_iommu, "amd_iommu"); -- 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/