From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: Re: [PATCH 0/11] RFC: PCI using capabilitities Date: Sun, 11 Dec 2011 14:48:43 +0200 Message-ID: <1323607723.4063.5.camel@lappy> References: <87pqfzgy6p.fsf@rustcorp.com.au> <1323358657.32487.9.camel@lappy> <4EE4726F.3010503@redhat.com> <1323597832.4063.4.camel@lappy> <20111211123057.GD11504@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Rusty Russell , virtualization , kvm@vger.kernel.org To: "Michael S. Tsirkin" Return-path: Received: from mail-bw0-f46.google.com ([209.85.214.46]:64066 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751836Ab1LKMtK (ORCPT ); Sun, 11 Dec 2011 07:49:10 -0500 Received: by bkcjm19 with SMTP id jm19so518814bkc.19 for ; Sun, 11 Dec 2011 04:49:09 -0800 (PST) In-Reply-To: <20111211123057.GD11504@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Sun, 2011-12-11 at 14:30 +0200, Michael S. Tsirkin wrote: > On Sun, Dec 11, 2011 at 12:03:52PM +0200, Sasha Levin wrote: > > On Sun, 2011-12-11 at 11:05 +0200, Avi Kivity wrote: > > > mmios are strictly ordered. > > > > > > Perhaps your printfs are reordered by buffering? Are they from > > > different threads? Are you using coalesced mmio (which is still > > > strictly ordered, if used correctly)? > > > > I print the queue_selector and queue_address in the printfs, even if > > printfs were reordered they would be printing the data right, unlike > > they do now. It's the data in the printfs that matters, not their order. > > > > Same vcpu thread with both accesses. > > > > Not using coalesced mmio. > > Not sure why this would matter, but is the BAR a prefetcheable one? > Rusty's patch uses pci_iomap which maps a prefetcheable BAR > as cacheable. Wasn't defined as prefetchable, but I'm seeing same thing with or without it. -- Sasha.