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. Changes: - V3: - Refreshed to 6.1-rc5 - Added a new io-uring api for the prefer napi busy poll api and wire it to io_napi_busy_loop(). - Removed the unregister (implemented as register) - Added more performance results to the first commit message. - V2: - Add missing defines if CONFIG_NET_RX_BUSY_POLL is not defined - Changes signature of function io_napi_add_list to static inline if CONFIG_NET_RX_BUSY_POLL is not defined - define some functions as static Signed-off-by: Stefan Roesch <shr@xxxxxxxxxxxx> Stefan Roesch (3): io_uring: add napi busy polling support io_uring: add api to set napi busy poll timeout. io_uring: add api to set napi prefer busy poll include/linux/io_uring_types.h | 8 + include/uapi/linux/io_uring.h | 4 + io_uring/io_uring.c | 278 +++++++++++++++++++++++++++++++++ io_uring/napi.h | 22 +++ io_uring/poll.c | 3 + io_uring/sqpoll.c | 10 ++ 6 files changed, 325 insertions(+) create mode 100644 io_uring/napi.h base-commit: 094226ad94f471a9f19e8f8e7140a09c2625abaa -- 2.30.2