Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761431Ab3EAPHm (ORCPT ); Wed, 1 May 2013 11:07:42 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:53194 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755688Ab3EAPHg (ORCPT ); Wed, 1 May 2013 11:07:36 -0400 X-IronPort-AV: E=Sophos;i="4.87,589,1363132800"; d="scan'208";a="21567567" Date: Wed, 1 May 2013 16:07:07 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: Stefano Stabellini , "linux-kernel@vger.kernel.org" , "xen-devel@lists.xensource.com" Subject: Re: [PATCH 8/9] xen/smp/pvhvm: Don't initialize IRQ_WORKER as we are using the native one. In-Reply-To: <20130501145753.GB6614@phenom.dumpdata.com> Message-ID: References: <1366142947-18655-1-git-send-email-konrad.wilk@oracle.com> <1366142947-18655-9-git-send-email-konrad.wilk@oracle.com> <20130429183404.GA9431@phenom.dumpdata.com> <20130501145753.GB6614@phenom.dumpdata.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1674 Lines: 38 On Wed, 1 May 2013, Konrad Rzeszutek Wilk wrote: > On Wed, May 01, 2013 at 02:25:16PM +0100, Stefano Stabellini wrote: > > On Mon, 29 Apr 2013, Konrad Rzeszutek Wilk wrote: > > > On Fri, Apr 26, 2013 at 05:27:20PM +0100, Stefano Stabellini wrote: > > > > On Tue, 16 Apr 2013, Konrad Rzeszutek Wilk wrote: > > > > > There is no need to use the PV version of the IRQ_WORKER mechanism > > > > > as under PVHVM we are using the native version. The native > > > > > version is using the SMP API. > > > > > > > > > > They just sit around unused: > > > > > > > > > > 69: 0 0 xen-percpu-ipi irqwork0 > > > > > 83: 0 0 xen-percpu-ipi irqwork1 > > > > > > > > > > Signed-off-by: Konrad Rzeszutek Wilk > > > > > > > > Might be worth trying to make it work instead? > > > > Is it just because we don't set the apic->send_IPI_* functions to the > > > > xen specific version on PVHVM? > > > > > > > > > > Right. We use the baremetal mechanism to do it. And it works fine. > > > > OK, it works fine, but won't it generate many mores trap and emulate > > cycles? > > No idea. We can certainly make use of the PV IPI mechanism for IRQ_WORKER > type mechaism but I would have to play with xentrace to get a good handle > of what is involved (And how the v Posted interrupt thing affects this). > > Right now that is something I can't do (buried in bugs). OK -- 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/