From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752577Ab1ECG7v (ORCPT ); Tue, 3 May 2011 02:59:51 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:59811 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751870Ab1ECG7u (ORCPT ); Tue, 3 May 2011 02:59:50 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=OK+0WPs6ZqskpQ7oFR5+A7kguGrEeB1CQNM9u1wiTb+3DJ+uKD1/am8rK+p5h8dYnE BCXb2KlW6o428Whmb56V1KANzaIH3HX+SVB7CP1rML9gZAPYz4lBXUdNmt68ykjMABHq tVc7upt1aE13Um2sWdLmJyeb+qnnmm7VmNEtA= Message-ID: <4DBFA7E1.5090501@gmail.com> Date: Tue, 03 May 2011 10:59:45 +0400 From: Cyrill Gorcunov User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.14) Gecko/20110223 Thunderbird/3.1.8 MIME-Version: 1.0 To: Ingo Molnar CC: Suresh Siddha , LKML Subject: Re: [patch 1/2] x86, x2apic: minimize IPI register writes using cluster groups v4 References: <20110502113445.751391656@openvz.org> <20110502114024.222582172@openvz.org> <20110502132232.GA3873@elte.hu> <4DBEB96A.8000309@openvz.org> <4DBEBE72.3040702@gmail.com> <20110502150552.GA21974@elte.hu> <4DBECAB4.7020809@gmail.com> <20110503063130.GC7751@elte.hu> In-Reply-To: <20110503063130.GC7751@elte.hu> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/03/2011 10:31 AM, Ingo Molnar wrote: > > * Cyrill Gorcunov wrote: > >> On 05/02/2011 07:05 PM, Ingo Molnar wrote: >> ... >>>> >>>> Ingo, would it be fine to make apic->init() either _before_ this series or >>>> on top of them (because if I introduce it inside this particular patch it >>>> would contain some unrelated code snippets such as .init = NULL for all apics >>>> declaration). >>> >>> Of course it should be a separate patch - even this patch looks a bit large - >>> any way to split it up further? >> >> Well, for this particular path the only minimum is used, so i fear there is no >> way to split it, probably I could drop some 'cleanup' bits from it and make it >> a separate one. Gimme some time. > > Well, first try to do *all* preparatory and cleanup changes that have low > regression risk. OK > > *Then* keep the most dangerous part to the end of it - so that it's easily > reverted, should the need arise. Preferably the dangerous part should be much > smaller than: > > 3 files changed, 136 insertions(+), 46 deletions(-) > > And no, it is not at all true that there is 'no way' to split the patch up any > further: you could certainly add the data structures, init methods and such > support code (which is low regression risk) in a separate patch than the > changes that modify the existing x2apic_send_IPI_mask_allbutself() function and > such. OK > > Also, the loop body in the new __x2apic_send_IPI_mask() function could > certainly be split out into a helper inline, making the code flow clearer. OK, will try so, thanks Ingo! > > Thanks, > > Ingo -- Thanks, Cyrill