Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933591Ab3GWQJG (ORCPT ); Tue, 23 Jul 2013 12:09:06 -0400 Received: from mail-vc0-f176.google.com ([209.85.220.176]:47084 "EHLO mail-vc0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933551Ab3GWQJB (ORCPT ); Tue, 23 Jul 2013 12:09:01 -0400 MIME-Version: 1.0 In-Reply-To: <20130723154736.GB27075@twins.programming.kicks-ass.net> References: <1374594257.5382.5.camel@localhost.localdomain> <20130723154736.GB27075@twins.programming.kicks-ass.net> Date: Tue, 23 Jul 2013 22:09:00 +0600 Message-ID: Subject: Re: [PATCH, RFC] sched: update_top_cache_domain only at the times of building sched domain. From: Rakib Mullick To: Peter Zijlstra Cc: mingo@kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1399 Lines: 32 On Tue, Jul 23, 2013 at 9:47 PM, Peter Zijlstra wrote: > On Tue, Jul 23, 2013 at 09:44:17PM +0600, Rakib Mullick wrote: >> Currently, update_top_cache_domain() is called whenever schedule domain is built or destroyed. But, the following >> callpath shows that they're at the same callpath and can be avoided update_top_cache_domain() while destroying schedule >> domain and update only at the times of building schedule domains. >> >> partition_sched_domains() >> detach_destroy_domain() >> cpu_attach_domain() >> update_top_cache_domain() >> build_sched_domains() >> cpu_attach_domain() >> update_top_cache_domain() >> > > Does it really matter? Why should we do it twice? More importantly at the time of destroying even though we know it'll be built again just few moment later. > > > This just makes the code uglier for no gain afaict. > > If you really need to do this, key off @sd == NULL or something. Sorry, would you please a bit more clearer? I can't pick what you're suggesting. -- 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/