From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH 08/12] xen/grant-table: add a mechanism to safely unmap pages that are in use Date: Wed, 7 Jan 2015 13:33:09 +0000 Message-ID: <1420637589.18631.87.camel@citrix.com> References: <1420570657-8203-1-git-send-email-david.vrabel@citrix.com> <1420570657-8203-9-git-send-email-david.vrabel@citrix.com> <1420632022.18631.58.camel@citrix.com> <54AD2F93.209@citrix.com> <1420637091.18631.84.camel@citrix.com> <54AD3504.60100@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Y8qja-0007lU-Dw for xen-devel@lists.xenproject.org; Wed, 07 Jan 2015 13:33:14 +0000 In-Reply-To: <54AD3504.60100@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: David Vrabel Cc: xen-devel@lists.xenproject.org, Boris Ostrovsky , Jenny Herbert , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On Wed, 2015-01-07 at 13:30 +0000, David Vrabel wrote: > On 07/01/15 13:24, Ian Campbell wrote: > > On Wed, 2015-01-07 at 13:07 +0000, David Vrabel wrote: > > > >> We don't use this safe unmap mechanism for netback because the zero copy > >> stuff means we don't need it and the polling on the unmap is high > >> latency and only good enough if the polling is needed very rarely. > > > > I'd think it should be rare for netback too unless your network is made > > of wet string. > > Hmmm. Yes, this might be worth looking at but I would prefer to do it > to it as a follow up to this series. Sure.