From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id DAB3F6B025E for ; Fri, 21 Oct 2016 02:37:06 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id n85so45142333pfi.7 for ; Thu, 20 Oct 2016 23:37:06 -0700 (PDT) Received: from mga05.intel.com (mga05.intel.com. [192.55.52.43]) by mx.google.com with ESMTPS id lk10si1044761pab.109.2016.10.20.23.37.06 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Oct 2016 23:37:06 -0700 (PDT) From: Liang Li Subject: [RESEND PATCH v3 kernel 2/7] virtio-balloon: define new feature bit and page bitmap head Date: Fri, 21 Oct 2016 14:24:35 +0800 Message-Id: <1477031080-12616-3-git-send-email-liang.z.li@intel.com> In-Reply-To: <1477031080-12616-1-git-send-email-liang.z.li@intel.com> References: <1477031080-12616-1-git-send-email-liang.z.li@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: mst@redhat.com Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-mm@kvack.org, virtio-dev@lists.oasis-open.org, kvm@vger.kernel.org, qemu-devel@nongnu.org, quintela@redhat.com, dgilbert@redhat.com, dave.hansen@intel.com, pbonzini@redhat.com, cornelia.huck@de.ibm.com, amit.shah@redhat.com, Liang Li 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 --- 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..d3b182a 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)); +/* Page bitmap header structure */ +struct balloon_bmap_hdr { + /* Used to distinguish different request */ + __virtio16 cmd; + /* Shift width of page in the bitmap */ + __virtio16 page_shift; + /* flag used to identify different status */ + __virtio16 flag; + /* Reserved */ + __virtio16 reserved; + /* ID of the request */ + __virtio64 req_id; + /* The pfn of 0 bit in the bitmap */ + __virtio64 start_pfn; + /* The length of the bitmap, in bytes */ + __virtio64 bmap_len; +}; + #endif /* _LINUX_VIRTIO_BALLOON_H */ -- 1.8.3.1 -- 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