From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422746AbWJRSJ4 (ORCPT ); Wed, 18 Oct 2006 14:09:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422748AbWJRSJ4 (ORCPT ); Wed, 18 Oct 2006 14:09:56 -0400 Received: from smtp107.mail.mud.yahoo.com ([209.191.85.217]:53590 "HELO smtp107.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1422746AbWJRSJz (ORCPT ); Wed, 18 Oct 2006 14:09:55 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=lmdLKau+6EaZskQ5binMzCXl53qvnN7hlB82LMYRBBnrqwNiZSE0oJm/NaDG8SEOkOlMd6ljU9lHBP+rnYAd6OmAVuqwJCgLpwMU9i5MmtqXY188WienScArSNSrJVy1Tb1w/YChqSKsdlvgjLOxvSwkZh0KuPV73J4YUYkKaLs= ; Message-ID: <45366DF0.6040702@yahoo.com.au> Date: Thu, 19 Oct 2006 04:09:52 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Christoph Lameter CC: "Siddha, Suresh B" , Ingo Molnar , Peter Williams , linux-kernel@vger.kernel.org Subject: Re: [RFC] sched_tick with interrupts enabled References: <4536629C.4050807@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Christoph Lameter wrote: >>After that, it might be acceptable to call rebalance_tick from a tasklet, >>although it would be uneeded overhead on small systems. It might be better > > > Here is a patch that only runs rebalance tick from a tasklet in the > scheduler. For UP there will be no tasklet. > > [RFC] sched_rebalance_tick with interrupts enabled > > scheduler_tick() has the potential of running for some time if f.e. > sched_domains for a system with 1024 processors have to be balanced. > We currently do all of that with interrupts disabled. So we may be unable > to service interrupts for some time. Most of that time is potentially > spend in rebalance_tick. > > This patch splits off rebalance_tick from scheduler_tick and schedules > it via a tasklet. > > Signed-off-by: Christoph Lameter wake_priority_sleeper should not be called from rebalance_tick. That code was OK where it was before, I think. And you need to now turn off interrupts when doing the locking in load_balance. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com