[RFC,v1,0/2] io_uring: add napi busy polling support

Message

Stefan Roesch Nov. 3, 2022, 8:39 p.m. UTC

This adds the napi busy polling support in io_uring.c. It adds a new
napi_list to the io_ring_ctx structure. This list contains the list of
napi_id's that are currently enabled for busy polling. This list is
used to determine which napi id's enabled busy polling.

To set the new napi busy poll timeout, a new io-uring api has been
added. It sets the napi busy poll timeout for the corresponding ring.

There is also a corresponding liburing patch series, which enables this
feature. The name of the series is "liburing: add add api for napi busy
poll timeout". It also contains two programs to test the this.

Testing has shown that the round-trip times are reduced to 38us from
55us by enabling napi busy polling with a busy poll timeout of 100us.

Signed-off-by: Stefan Roesch <[e-mail]>

Stefan Roesch (2):
  io_uring: add napi busy polling support
  io_uring: add api to set napi busy poll timeout.

 include/linux/io_uring_types.h |   6 +
 include/uapi/linux/io_uring.h  |   4 +
 io_uring/io_uring.c            | 255 +++++++++++++++++++++++++++++++++
 io_uring/napi.h                |  22 +++
 io_uring/poll.c                |   3 +
 io_uring/sqpoll.c              |   9 ++
 6 files changed, 299 insertions(+)
 create mode 100644 io_uring/napi.h


base-commit: 8f71a2b3f435f29b787537d1abedaa7d8ebe6647