From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f71.google.com (mail-it0-f71.google.com [209.85.214.71]) by kanga.kvack.org (Postfix) with ESMTP id A7A4E6B0069 for ; Fri, 13 Jan 2017 04:24:29 -0500 (EST) Received: by mail-it0-f71.google.com with SMTP id 203so52786702ith.3 for ; Fri, 13 Jan 2017 01:24:29 -0800 (PST) Received: from mga09.intel.com (mga09.intel.com. [134.134.136.24]) by mx.google.com with ESMTPS id b5si12155348pgh.79.2017.01.13.01.24.28 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Jan 2017 01:24:29 -0800 (PST) From: "Li, Liang Z" Subject: RE: [virtio-dev] Re: [PATCH v6 kernel 2/5] virtio-balloon: define new feature bit and head struct Date: Fri, 13 Jan 2017 09:24:22 +0000 Message-ID: References: <1482303148-22059-1-git-send-email-liang.z.li@intel.com> <1482303148-22059-3-git-send-email-liang.z.li@intel.com> <20170112185719-mutt-send-email-mst@kernel.org> In-Reply-To: <20170112185719-mutt-send-email-mst@kernel.org> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: "Michael S. Tsirkin" Cc: "kvm@vger.kernel.org" , "virtio-dev@lists.oasis-open.org" , "qemu-devel@nongnu.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "amit.shah@redhat.com" , "Hansen, Dave" , "cornelia.huck@de.ibm.com" , "pbonzini@redhat.com" , "david@redhat.com" , "aarcange@redhat.com" , "dgilbert@redhat.com" , "quintela@redhat.com" > On Wed, Dec 21, 2016 at 02:52:25PM +0800, Liang Li wrote: > > Add a new feature which supports sending the page information with > > range array. The current implementation uses PFNs array, which is not > > very efficient. Using ranges can improve the performance of > > inflating/deflating significantly. > > > > Signed-off-by: Liang Li > > Cc: Michael S. Tsirkin > > Cc: Paolo Bonzini > > Cc: Cornelia Huck > > Cc: Amit Shah > > Cc: Dave Hansen > > Cc: Andrea Arcangeli > > Cc: David Hildenbrand > > --- > > include/uapi/linux/virtio_balloon.h | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > > > diff --git a/include/uapi/linux/virtio_balloon.h > > b/include/uapi/linux/virtio_balloon.h > > index 343d7dd..2f850bf 100644 > > --- a/include/uapi/linux/virtio_balloon.h > > +++ b/include/uapi/linux/virtio_balloon.h > > @@ -34,10 +34,14 @@ > > #define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before > reclaiming pages */ > > #define VIRTIO_BALLOON_F_STATS_VQ 1 /* Memory Stats virtqueue > */ > > #define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 2 /* Deflate balloon > on OOM */ > > +#define VIRTIO_BALLOON_F_PAGE_RANGE 3 /* Send page info > with ranges */ > > > > /* Size of a PFN in the balloon interface. */ #define > > VIRTIO_BALLOON_PFN_SHIFT 12 > > > > +/* Bits width for the length of the pfn range */ >=20 > What does this mean? Couldn't figure it out. >=20 > > +#define VIRTIO_BALLOON_NR_PFN_BITS 12 > > + > > struct virtio_balloon_config { > > /* Number of pages host wants Guest to give up. */ > > __u32 num_pages; > > @@ -82,4 +86,12 @@ struct virtio_balloon_stat { > > __virtio64 val; > > } __attribute__((packed)); > > > > +/* Response header structure */ > > +struct virtio_balloon_resp_hdr { > > + __le64 cmd : 8; /* Distinguish different requests type */ > > + __le64 flag: 8; /* Mark status for a specific request type */ > > + __le64 id : 16; /* Distinguish requests of a specific type */ > > + __le64 data_len: 32; /* Length of the following data, in bytes */ >=20 > This use of __le64 makes no sense. Just use u8/le16/le32 pls. >=20 Got it, will change in the next version.=20 And could help take a look at other parts? as well as the QEMU part. Thanks! Liang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org