From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54890) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dVsGW-0005co-7y for qemu-devel@nongnu.org; Fri, 14 Jul 2017 00:31:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dVsGT-0006J0-4N for qemu-devel@nongnu.org; Fri, 14 Jul 2017 00:31:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48302) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dVsGS-0006Ii-UY for qemu-devel@nongnu.org; Fri, 14 Jul 2017 00:31:41 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DFB714E024 for ; Fri, 14 Jul 2017 04:31:39 +0000 (UTC) Date: Fri, 14 Jul 2017 12:31:36 +0800 From: Peter Xu Message-ID: <20170714043136.GJ27284@pxdev.xzpeter.org> References: <1499847223-8078-1-git-send-email-peterx@redhat.com> <1499847223-8078-3-git-send-email-peterx@redhat.com> <20170713204619-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20170713204619-mutt-send-email-mst@kernel.org> Subject: Re: [Qemu-devel] [PATCH v3 2/4] intel_iommu: let iotlb size tunable List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: qemu-devel@nongnu.org, Jason Wang On Thu, Jul 13, 2017 at 08:47:00PM +0300, Michael S. Tsirkin wrote: > On Wed, Jul 12, 2017 at 04:13:41PM +0800, Peter Xu wrote: > > We were having static IOTLB size as 1024. Let it be a tunable. We can > > also turns IOTLB off if we want, by specify the size as zero. > > > > The tunable is named as "x-iotlb-size" since that should not really be > > something used by user yet, but mostly for debugging purpose now. > > > > Signed-off-by: Peter Xu > > I'm somewhat vary of adding tunables just for developers to play with. > People will find and abuse them :) I would think it convenient (especially with "x-") and I would never worry about people using it (I really see nothing dangerous...). But if you don't like it, I can drop it in next version for sure. Thanks, -- Peter Xu