Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933491Ab0FROfw (ORCPT ); Fri, 18 Jun 2010 10:35:52 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:43623 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932434Ab0FROfv (ORCPT ); Fri, 18 Jun 2010 10:35:51 -0400 Date: Fri, 18 Jun 2010 16:35:32 +0200 From: Ingo Molnar To: huang ying Cc: Hidetoshi Seto , Huang Ying , Fr??d??ric Weisbecker , Don Zickus , Peter Zijlstra , "H. Peter Anvin" , linux-kernel@vger.kernel.org, Andi Kleen Subject: Re: [RFC 1/3] Unified NMI delayed call mechanism Message-ID: <20100618143532.GA10886@elte.hu> References: <1276334896-7075-1-git-send-email-ying.huang@intel.com> <20100612102558.GA4000@elte.hu> <4C15A5D1.1040104@jp.fujitsu.com> <20100618094838.GD23977@elte.hu> <20100618124551.GC7612@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: 0.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.5 required=5.9 tests=BAYES_40 autolearn=no SpamAssassin version=3.2.5 0.5 BAYES_40 BODY: Bayesian spam probability is 20 to 40% [score: 0.2347] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1753 Lines: 37 * huang ying wrote: > On Fri, Jun 18, 2010 at 8:45 PM, Ingo Molnar wrote: > >> >> [...] ??At least APEI will use NMI to report some hardware events (likely > >> >> error) to kernel. ??So I suppose we will go to have a delayed call as an > >> >> event handler for APEI. > >> > > >> > Yep, that makes sense. I wasnt arguing against the functionality itself, i > >> > was arguing against the illogical layering that limits its utility. By > >> > making it part of perf events it becomes a generic part of that framework > >> > and can be used by anything that deals with events and uses that > >> > framework. > >> > >> I think the the 'layering' in the patchset helps instead of 'limits' its > >> utility. It is designed to be as general as possible, so that it can be used > >> by both perf and other NMI users. Do you think so? > > > > What other NMI users do you mean? EDAC/MCE is going to go utilize events > > as well (away from the horrible /dev/mcelog interface), the NMI watchdog > > already did it and the perf tool obviously does as well. There's a few > > leftovers like kcrash which isnt really event centric and i dont think it > > needs to be converted. > > But why not just make it more general? It does not hurt anyone including > perf. Because it's not actually more generic that way - just look at the code. It's x86 specific, plus it ties it to NMI delivery while the concept of delayed execution has nothing to do with NMIs. 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/