From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755212AbcKBGas (ORCPT ); Wed, 2 Nov 2016 02:30:48 -0400 Received: from mga07.intel.com ([134.134.136.100]:58317 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753044AbcKBGai (ORCPT ); Wed, 2 Nov 2016 02:30:38 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,583,1473145200"; d="scan'208";a="26774432" From: Liang Li To: mst@redhat.com, dave.hansen@intel.com Cc: pbonzini@redhat.com, amit.shah@redhat.com, quintela@redhat.com, dgilbert@redhat.com, qemu-devel@nongnu.org, kvm@vger.kernel.org, virtio-dev@lists.oasis-open.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, mgorman@techsingularity.net, cornelia.huck@de.ibm.com, Liang Li Subject: [PATCH kernel v4 2/7] virtio-balloon: define new feature bit and head struct Date: Wed, 2 Nov 2016 14:17:22 +0800 Message-Id: <1478067447-24654-3-git-send-email-liang.z.li@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1478067447-24654-1-git-send-email-liang.z.li@intel.com> References: <1478067447-24654-1-git-send-email-liang.z.li@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a new feature which supports sending the page information with a bitmap. The current implementation uses PFNs array, which is not very efficient. Using bitmap can improve the performance of inflating/deflating significantly The page bitmap header will used to tell the host some information about the page bitmap. e.g. the page size, page bitmap length and start pfn. Signed-off-by: Liang Li Cc: Michael S. Tsirkin Cc: Paolo Bonzini Cc: Cornelia Huck Cc: Amit Shah Cc: Dave Hansen --- include/uapi/linux/virtio_balloon.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/include/uapi/linux/virtio_balloon.h b/include/uapi/linux/virtio_balloon.h index 343d7dd..bed6f41 100644 --- a/include/uapi/linux/virtio_balloon.h +++ b/include/uapi/linux/virtio_balloon.h @@ -34,6 +34,7 @@ #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_BITMAP 3 /* Send page info with bitmap */ /* Size of a PFN in the balloon interface. */ #define VIRTIO_BALLOON_PFN_SHIFT 12 @@ -82,4 +83,22 @@ 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 */ +}; + +/* Page bitmap header structure */ +struct virtio_balloon_bmap_hdr { + struct { + __le64 start_pfn : 52; /* start pfn for the bitmap */ + __le64 page_shift : 6; /* page shift width, in bytes */ + __le64 bmap_len : 6; /* bitmap length, in bytes */ + } head; + __le64 bmap[0]; +}; + #endif /* _LINUX_VIRTIO_BALLOON_H */ -- 1.8.3.1