Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933937Ab1CYJpG (ORCPT ); Fri, 25 Mar 2011 05:45:06 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:48992 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932140Ab1CYJpE (ORCPT ); Fri, 25 Mar 2011 05:45:04 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=SFJgO1Czwwkh2gsIByxawHga2+fWe0pfsskSQdQXPDQnPvRkVryG3uo6mb9RDVrFoU FfLllLWhx8C0KWIQAqIxFBnL9zuE9vBtf1Y8EcYlJnp7CEXeNFrM8TlZ4b6aaWM3gNXE 3wmBug75sYFe6ky9PXjIfLQaoFSSO3NPHNcwE= Subject: Re: [PATCH RFC] x86: avoid atomic operation in test_and_set_bit_lock if possible From: Eric Dumazet To: Ingo Molnar Cc: Andi Kleen , Linus Torvalds , Jack Steiner , Jan Beulich , Borislav Petkov , Peter Zijlstra , Nick Piggin , "x86@kernel.org" , Thomas Gleixner , Andrew Morton , Ingo Molnar , tee@sgi.com, Nikanth Karthikesan , "linux-kernel@vger.kernel.org" , "H. Peter Anvin" In-Reply-To: <20110325093228.GB13640@elte.hu> References: <4D8B83DA02000078000381DE@vpn.id2.novell.com> <20110324173020.GA26761@sgi.com> <20110324200010.GB7957@elte.hu> <1300999682.2714.23.camel@edumazet-laptop> <20110324205422.GB2393@elte.hu> <1301000557.2714.33.camel@edumazet-laptop> <20110324235654.GM21838@one.firstfloor.org> <1301032040.2714.569.camel@edumazet-laptop> <20110325093228.GB13640@elte.hu> Content-Type: text/plain; charset="UTF-8" Date: Fri, 25 Mar 2011 10:44:58 +0100 Message-ID: <1301046298.3268.4.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1586 Lines: 39 Le vendredi 25 mars 2011 à 10:32 +0100, Ingo Molnar a écrit : > * Eric Dumazet wrote: > > > Le vendredi 25 mars 2011 à 00:56 +0100, Andi Kleen a écrit : > > > > never EVER seen any good explanation of why that particular sh*t > > > > argument would b true. It seems to be purely about politics, where > > > > some idiotic vendor (namely HP) has convinced Intel that they really > > > > need it. To the point where some engineers seem to have bought into > > > > the whole thing and actually believe that fairy tale ("firmware can do > > > > better" - hah! They must be feeding people some bad drugs at the > > > > cafeteria) > > > > > > For the record I don't think it's a good idea for the BIOS to do > > > this (and I'm not aware of any engineer who does), > > > but I think Linux should do better than just disabling PMU use when > > > this happens. > > > > > > However I suspect taking over SCI would cause endless problems > > > and is very likely not a good idea. > > > > I tried many different changes in BIOS and all failed (the machine is > > damn slow at boot, this takes age). > > > > I am stuck :( > > Could you please try the patch below? This obviously works, but you probably need to make a full pass to make sure we dont have a MSR failure -this should return false in this case. -- 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/