Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754135AbXLDM1U (ORCPT ); Tue, 4 Dec 2007 07:27:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752925AbXLDM1L (ORCPT ); Tue, 4 Dec 2007 07:27:11 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:50615 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752671AbXLDM1K (ORCPT ); Tue, 4 Dec 2007 07:27:10 -0500 Date: Tue, 4 Dec 2007 13:26:49 +0100 From: Ingo Molnar To: Len Brown Cc: "Eric W. Biederman" , Natalie Protasevich , Andi Kleen , Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: [PATCH] i386 IOAPIC: de-fang IRQ compression Message-ID: <20071204122649.GB27286@elte.hu> References: <200711280121.18376.lenb@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200711280121.18376.lenb@kernel.org> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1266 Lines: 30 * Len Brown wrote: > So while the irq compression code on i386 should really > be deleted -- even before merging the x86_64 irq-overhaul, > this patch simply disables it on all high volume systems > to avoid problems #1 and #2 on most all i386 systems. > > A large system with pin numbers >=64 will still have compression > to conserve limited IRQ numbers for sparse IOAPICS. However, > the vast majority of the planet, those with only pin numbers < 64 > will use an identity GSI -> IRQ mapping. > > Signed-off-by: Len Brown thanks for the patch and the extensive description. I've applied this to x86.git. Do you agree that this has no urgency for v2.6.24 and is thus v2.6.25 material? would you be interested in doing a follow-up patch as well that just yanks all of the irq compression code? That would keep things nicely bisectable and testable - the second, larger patch would be a NOP in theory on most systems. 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/