From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34961) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e6atN-0004xT-Gl for qemu-devel@nongnu.org; Mon, 23 Oct 2017 07:27:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e6atJ-0000pT-IV for qemu-devel@nongnu.org; Mon, 23 Oct 2017 07:27:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56846) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e6atJ-0000op-Cq for qemu-devel@nongnu.org; Mon, 23 Oct 2017 07:27:33 -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 823437F7DA for ; Mon, 23 Oct 2017 11:27:31 +0000 (UTC) Date: Mon, 23 Oct 2017 07:27:31 -0400 (EDT) From: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Message-ID: <1938855984.30684033.1508758051014.JavaMail.zimbra@redhat.com> In-Reply-To: <20171023102339.GF16472@redhat.com> References: <20171023095910.23202-1-marcandre.lureau@redhat.com> <20171023095910.23202-5-marcandre.lureau@redhat.com> <20171023102339.GF16472@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v5 4/6] memfd: add hugetlb support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: qemu-devel@nongnu.org, pbonzini@redhat.com, ehabkost@redhat.com Hi ----- Original Message ----- > On Mon, Oct 23, 2017 at 10:59:08AM +0100, Marc-Andr=C3=A9 Lureau wrote: > > Linux commit 749df87bd7bee5a79cef073f5d032ddb2b211de8 (v4.14-rc1) > > added a new flag MFD_HUGETLB to memfd_create() that specify the file > > to be created resides in the hugetlbfs filesystem. This is the > > generic hugetlbfs filesystem not associated with any specific mount > > point. >=20 > How do you know and/or control what size huge pages are used, > when the platform supports many sizes ? >>From linux commit message: "As with other system calls that request hugetlbfs backed pages, there is the ability to encode huge page size in the flag arguments." I didn't add this option to memfd backend, as I don't know how generally us= eful that is, and if there is already a similar option in qemu (probably no= t?). It could be easily added later. >=20 > Regards, > Daniel > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberran= ge > |:| > |: https://libvirt.org -o- https://fstop138.berrange.c= om > |:| > |: https://entangle-photo.org -o- https://www.instagram.com/dberran= ge > |:| >=20