On 2018年05月21日 00:25, Wei Xu wrote:
On Wed, May 16, 2018 at 08:32:13PM +0800, Jason Wang wrote:
Hi all:
This RFC implement packed ring layout. The code were tested with
Tiwei's RFC V3 ahttps://lkml.org/lkml/2018/4/25/34. Some fixups and
tweaks were needed on top of Tiwei's code to make it run for event
index.
Could you please show the change based on Tiwei's code to easy other's
test?
Please try Tiwei's V4 instead of just waiting for the fixup. It should
work unless you don't try zerocopy and vIOMMU.
Pktgen reports about 20% improvement on PPS (event index is off). More
testing is ongoing.
Notes for tester:
- Start from this version, vhost need qemu co-operation to work
correctly. Or you can comment out the packed specific code for
GET/SET_VRING_BASE.
Do you mean the code in vhost_virtqueue_start/stop?
For qemu, probably.
Both Tiwei's and your v3
work fortunately correctly which should be avoided since the ring should be
definitely different.
I don't understand this, you mean reset work?
Thanks
Wei
Changes from V3:
- Fix math on event idx checking
- Sync last avail wrap counter through GET/SET_VRING_BASE
- remove desc_event prefix in the driver/device structure
Changes from V2:
- do not use & in checking desc_event_flags
- off should be most significant bit
- remove the workaround of mergeable buffer for dpdk prototype
- id should be in the last descriptor in the chain
- keep _F_WRITE for write descriptor when adding used
- device flags updating should use ADDR_USED type
- return error on unexpected unavail descriptor in a chain
- return false in vhost_ve_avail_empty is descriptor is available
- track last seen avail_wrap_counter
- correctly examine available descriptor in get_indirect_packed()
- vhost_idx_diff should return u16 instead of bool
Changes from V1:
- Refactor vhost used elem code to avoid open coding on used elem
- Event suppression support (compile test only).
- Indirect descriptor support (compile test only).
- Zerocopy support.
- vIOMMU support.
- SCSI/VSOCK support (compile test only).
- Fix several bugs
Jason Wang (8):
vhost: move get_rx_bufs to vhost.c
vhost: hide used ring layout from device
vhost: do not use vring_used_elem
vhost_net: do not explicitly manipulate vhost_used_elem
vhost: vhost_put_user() can accept metadata type
virtio: introduce packed ring defines
vhost: packed ring support
vhost: event suppression for packed ring
drivers/vhost/net.c | 136 ++----
drivers/vhost/scsi.c | 62 +--
drivers/vhost/vhost.c | 861 ++++++++++++++++++++++++++++++++-----
drivers/vhost/vhost.h | 47 +-
drivers/vhost/vsock.c | 42 +-
include/uapi/linux/virtio_config.h | 9 +
include/uapi/linux/virtio_ring.h | 32 ++
7 files changed, 928 insertions(+), 261 deletions(-)
--
2.7.4
