kernel/linux.git/io_uring/notif.c, branch v6.2-rc2

io_uring/net: move mm accounting to a slower path

2022-11-21T14:38:31+00:00

We can also move mm accounting to the extended callbacks. It removes a few cycles from the hot path including skipping one function call and setting io_req_task_complete as a callback directly. For user backed I/O it shouldn't make any difference taking into considering atomic mm accounting and page pinning. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/1062f270273ad11c1b7b45ec59a6a317533d5e64.1667557923.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: move zc reporting from the hot path

2022-11-21T14:38:31+00:00

Add custom tw and notif callbacks on top of usual bits also handling zc reporting. That moves it from the hot path. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/40de4a6409042478e1f35adc4912e23226cb1b5c.1667557923.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: inline io_notif_flush()

2022-11-21T14:38:31+00:00

io_notif_flush() is pretty simple, we can inline it. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/332359e7bd124138dfe51340bbec829c9b265c18.1667557923.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: rename io_uring_tx_zerocopy_callback

2022-11-21T14:38:31+00:00

Just a simple renaming patch, io_uring_tx_zerocopy_callback() is too bulky and doesn't follow usual naming style. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/24d78325403ca6dcb1ec4bced1e33cacc9b832a5.1667557923.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: preset notif tw handler

2022-11-21T14:38:31+00:00

We're going to have multiple notification tw functions. In preparation for future changes default the tw callback in advance so later we can replace it with other versions. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/7acdbea5e20eadd844513320cd454af14ba50f64.1667557923.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: remove extra notif rsrc setup

2022-11-21T14:38:31+00:00

io_send_zc_prep() sets up notification's rsrc_node when needed, don't unconditionally install it on notif alloc. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/dbe4875ac33e180b9799d8537a5e27935e82aac4.1667557923.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: introduce IORING_SEND_ZC_REPORT_USAGE flag

2022-11-21T14:38:31+00:00

It might be useful for applications to detect if a zero copy transfer with SEND[MSG]_ZC was actually possible or not. The application can fallback to plain SEND[MSG] in order to avoid the overhead of two cqes per request. Or it can generate a log message that could indicate to an administrator that no zero copy was possible and could explain degraded performance. Cc: stable@vger.kernel.org # 6.1 Link: https://lore.kernel.org/io-uring/fb6a7599-8a9b-15e5-9b64-6cd9d01c6ff4@gmail.com/T/#m2b0d9df94ce43b0e69e6c089bdff0ce6babbdfaa Signed-off-by: Stefan Metzmacher Reviewed-by: Pavel Begunkov Link: https://lore.kernel.org/r/8945b01756d902f5d5b0667f20b957ad3f742e5e.1666895626.git.metze@samba.org Signed-off-by: Jens Axboe

io_uring/notif: Remove the unused function io_notif_complete()

2022-09-05T17:42:39+00:00

The function io_notif_complete() is defined in the notif.c file, but not called elsewhere, so delete this unused function. io_uring/notif.c:24:20: warning: unused function 'io_notif_complete' [-Wunused-function]. Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2047 Reported-by: Abaci Robot Signed-off-by: Jiapeng Chong Reviewed-by: Pavel Begunkov Link: https://lore.kernel.org/r/20220905020436.51894-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Jens Axboe

io_uring/net: simplify zerocopy send user API

2022-09-01T15:13:33+00:00

Following user feedback, this patch simplifies zerocopy send API. One of the main complaints is that the current API is difficult with the userspace managing notification slots, and then send retries with error handling make it even worse. Instead of keeping notification slots change it to the per-request notifications model, which posts both completion and notification CQEs for each request when any data has been sent, and only one CQE if it fails. All notification CQEs will have IORING_CQE_F_NOTIF set and IORING_CQE_F_MORE in completion CQEs indicates whether to wait a notification or not. IOSQE_CQE_SKIP_SUCCESS is disallowed with zerocopy sends for now. This is less flexible, but greatly simplifies the user API and also the kernel implementation. We reuse notif helpers in this patch, but in the future there won't be need for keeping two requests. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/95287640ab98fc9417370afb16e310677c63e6ce.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/notif: remove notif registration

2022-09-01T15:13:33+00:00

We're going to remove the userspace exposed zerocopy notification API, remove notification registration. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/6ff00b97be99869c386958a990593c9c31cf105b.1662027856.git.asml.silence@gmail.com Signed-off-by: Jens Axboe