linux-kernel - [RFC for qemu v4 0/2] virtio-balloon: Add option cont-pages to set VIRTIO_BALLOON_F_CONT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 16 Jul 2020 10:41:53 +0800
From:   Hui Zhu <teawater@...il.com>
To:     mst@...hat.com, david@...hat.com, jasowang@...hat.com,
        akpm@...ux-foundation.org,
        virtualization@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        qemu-devel@...gnu.org, virtio-dev@...ts.oasis-open.org
Cc:     Hui Zhu <teawater@...il.com>
Subject: [RFC for qemu v4 0/2] virtio-balloon: Add option cont-pages to set VIRTIO_BALLOON_F_CONT_PAGES

Code of current version for Linux and qemu is available in [1] and [2].
Update of this version:
1. Report continuous pages will increase the speed.  So added deflate
   continuous pages.
2. According to the comments from David in [3], added 2 new vqs icvq and
   dcvq to get continuous pages with format 32 bits pfn and 32 bits size.

Following is the introduction of the function.
Set option cont-pages to on will open flags VIRTIO_BALLOON_F_CONT_PAGES.
qemu will get continuous pages from icvq and dcvq and do madvise
MADV_WILLNEED and MADV_DONTNEED with the pages.
Opening this flag can bring two benefits:
1. Increase the speed of balloon inflate and deflate.
2. Decrease the splitted THPs number in the host.

[1] https://github.com/teawater/linux/tree/balloon_conts
[2] https://github.com/teawater/qemu/tree/balloon_conts
[3] https://lkml.org/lkml/2020/5/13/1211

Hui Zhu (2):
  virtio_balloon: Add cont-pages and icvq
  virtio_balloon: Add dcvq to deflate continuous pages

 hw/virtio/virtio-balloon.c                      |   92 +++++++++++++++---------
 include/hw/virtio/virtio-balloon.h              |    2
 include/standard-headers/linux/virtio_balloon.h |    1
 3 files changed, 63 insertions(+), 32 deletions(-)