[v4,0/3] vhost: memslot handling improvements

Message

David Hildenbrand May 23, 2023, 6:59 p.m. UTC

Following up on my previous work to make virtio-mem consume multiple
memslots dynamically [1] that requires precise accounting between used vs.
reserved memslots, I realized that vhost makes this extra hard by
filtering out some memory region sections (so they don't consume a
memslot) in the vhost-user case, which messes up the whole memslot
accounting.

This series fixes what I found to be broken and prepares for more work on
[1]. Further, it cleanes up the merge checks that I consider unnecessary.

[1] https://lkml.kernel.org/r/[e-mail]

Cc: "Michael S. Tsirkin" <[e-mail]>
Cc: Stefan Hajnoczi <[e-mail]>
Cc: Igor Mammedov <[e-mail]>
Cc: Paolo Bonzini <[e-mail]>
Cc: Peter Xu <[e-mail]>
Cc: "Philippe Mathieu-Daudé" <[e-mail]>

v3 -> v4:
- Add RBs
- "vhost: Rework memslot filtering and fix "used_memslot" tracking"
-- Fix check for free memslots (> 1 vs > 0)

v2 -> v3:
- Add ACKs
- "softmmu/physmem: Fixup qemu_ram_block_from_host() documentation"
-- Fix typo in description

v1 -> v2:
- "vhost: Rework memslot filtering and fix "used_memslot" tracking"
-- New approach: keep filtering, but make filtering less generic and
   track separately. This should keep any existing setups working.
- "softmmu/physmem: Fixup qemu_ram_block_from_host() documentation"
-- As requested by Igor

David Hildenbrand (3):
  vhost: Rework memslot filtering and fix "used_memslot" tracking
  vhost: Remove vhost_backend_can_merge() callback
  softmmu/physmem: Fixup qemu_ram_block_from_host() documentation

 hw/virtio/vhost-user.c            | 21 ++---------
 hw/virtio/vhost-vdpa.c            |  1 -
 hw/virtio/vhost.c                 | 62 ++++++++++++++++++++++++-------
 include/exec/cpu-common.h         | 15 ++++++++
 include/hw/virtio/vhost-backend.h |  9 +----
 softmmu/physmem.c                 | 17 ---------
 6 files changed, 68 insertions(+), 57 deletions(-)

Comments

David Hildenbrand June 23, 2023, 12:52 p.m. UTC | #1

On 23.05.23 20:59, David Hildenbrand wrote:
> Following up on my previous work to make virtio-mem consume multiple
> memslots dynamically [1] that requires precise accounting between used vs.
> reserved memslots, I realized that vhost makes this extra hard by
> filtering out some memory region sections (so they don't consume a
> memslot) in the vhost-user case, which messes up the whole memslot
> accounting.
> 
> This series fixes what I found to be broken and prepares for more work on
> [1]. Further, it cleanes up the merge checks that I consider unnecessary.
> 
> [1] https://lkml.kernel.org/r/[e-mail]
> 
> Cc: "Michael S. Tsirkin" <[e-mail]>
> Cc: Stefan Hajnoczi <[e-mail]>
> Cc: Igor Mammedov <[e-mail]>
> Cc: Paolo Bonzini <[e-mail]>
> Cc: Peter Xu <[e-mail]>
> Cc: "Philippe Mathieu-Daudé" <[e-mail]>
> 

Gentle ping that this wants to get picked up :)