kernel/linux.git/io_uring/notif.c, branch v6.1.168

io_uring/net: introduce IORING_SEND_ZC_REPORT_USAGE flag

2022-12-31T12:33:11+00:00

commit e307e6698165ca6508ed42c69cb1be76c8eb6a3c upstream. 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 Signed-off-by: Greg Kroah-Hartman

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

io_uring/notif: order notif vs send CQEs

2022-08-24T14:57:28+00:00

Currently, there is no ordering between notification CQEs and completions of the send flushing it, this quite complicates the userspace, especially since we don't flush notification when the send(+flush) request fails, i.e. there will be only one CQE. What we can do is to make sure that notification completions come only after sends. The easiest way to achieve this is to not try to complete a notification inline from io_sendzc() but defer it to task_work, considering that io-wq sendzc is disallowed CQEs will be naturally ordered because task_works will only be executed after we're done with submission and so inline completion. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/cddfd1c2bf91f22b9fe08e13b7dffdd8f858a151.1661342812.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: fix must_hold annotation

2022-08-24T14:57:00+00:00

Fix up the io_alloc_notif()'s __must_hold as we don't have a ctx argument there but should get it from the slot instead. Reported-by: Stefan Metzmacher Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/cbb0a920f18e0aed590bf58300af817b9befb8a3.1661342812.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: make io_kiocb_to_cmd() typesafe

2022-08-12T23:01:00+00:00

We need to make sure (at build time) that struct io_cmd_data is not casted to a structure that's larger. Signed-off-by: Stefan Metzmacher Link: https://lore.kernel.org/r/c024cdf25ae19fc0319d4180e2298bade8ed17b8.1660201408.git.metze@samba.org Signed-off-by: Jens Axboe

io_uring: consistently make use of io_notif_to_data()

2022-08-11T16:56:13+00:00

This makes the assignment typesafe. It prepares changing io_kiocb_to_cmd() in the next commit. Signed-off-by: Stefan Metzmacher Link: https://lore.kernel.org/r/8da6e9d12cf95ad4bc73274406d12bca7aabf72e.1660201408.git.metze@samba.org Signed-off-by: Jens Axboe

io_uring: notification completion optimisation

2022-07-27T14:50:50+00:00

We want to use all optimisations that we have for io_uring requests like completion batching, memory caching and more but for zc notifications. Fortunately, notification perfectly fit the request model so we can overlay them onto struct io_kiocb and use all the infratructure. Most of the fields of struct io_notif natively fits into io_kiocb, so we replace struct io_notif with struct io_kiocb carrying struct io_notif_data in the cmd cache line. Then we adapt io_alloc_notif() to use io_alloc_req()/io_alloc_req_refill(), and kill leftovers of hand coded caching. __io_notif_complete_tw() is converted to use io_uring's tw infra. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/9e010125175e80baf51f0ca63bdc7cc6a4a9fa56.1658913593.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring/net: make page accounting more consistent

2022-07-25T15:48:25+00:00

Make network page accounting more consistent with how buffer registration is working, i.e. account all memory to ctx->user. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/4aacfe64bbb81b27f9ecf5d5c219c69a07e5aa56.1658742118.git.asml.silence@gmail.com Signed-off-by: Jens Axboe