From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id E673C9000BD for ; Sun, 2 Oct 2011 10:58:51 -0400 (EDT) Message-ID: <4E887C23.4030600@tilera.com> Date: Sun, 2 Oct 2011 10:58:43 -0400 From: Chris Metcalf MIME-Version: 1.0 Subject: Re: [PATCH 0/5] Reduce cross CPU IPI interference References: <1316940890-24138-1-git-send-email-gilad@benyossef.com> <4E831A79.1030402@tilera.com> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Gilad Ben-Yossef Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Frederic Weisbecker , Russell King , linux-mm@kvack.org, Christoph Lameter , Pekka Enberg , Matt Mackall On 10/2/2011 4:44 AM, Gilad Ben-Yossef wrote: >> We have some code in our tree (not yet >> returned to the community) that tries to deal with some sources of interrupt >> jitter on tiles that are running isolcpu and want to be 100% in user space. > Yes, I think this work will benefit this kind of use case (CPU/user > space bound on a dedicated CPU) > the most, although other use cases can benefit as well (e.g. power > management with idle cores). > > Btw, do you have any plan to share the patches you mentioned? it could > save me a lot of time. Not wanting to > re-invent the wheel and all that... I'd like to, but getting the patch put together cleanly is still on my list behind a number of other things (glibc community return, kernel catch-up with a backlog of less controversial changes, customer crises, enhancements targeted to forthcoming releases, etc.; I'm sure you know the drill...) >>> This first version creates an on_each_cpu_mask infrastructure API (derived >>> from >>> existing arch specific versions in Tile and Arm) and uses it to turn two >>> global >>> IPI invocation to per CPU group invocations. >> The global version looks fine; I would probably make on_each_cpu() an inline >> in the !SMP case now that you are (correctly, I suspect) disabling >> interrupts when calling the function. >> > Good point. Will do. > > I will take this email as an ACK to the tile relevant changes, if that > is OK with you. Yes, definitely. Acked-by: Chris Metcalf -- Chris Metcalf, Tilera Corp. http://www.tilera.com -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org