user/sven/linux.git/io_uring/timeout.c, branch v6.7.9

io_uring: never overflow io_aux_cqe

2023-08-11T16:42:57Z

Now all callers of io_aux_cqe() set allow_overflow to false, remove the parameter and not allow overflowing auxilary multishot cqes. When CQ is full the function callers and all multishot requests in general are expected to complete the request. That prevents indefinite in-background grows of the overflow list and let's the userspace to handle the backlog at its own pace. Resubmitting a request should also be faster than accounting a bunch of overflows, so it should be better for perf when it happens, but a well behaving userspace should be trying to avoid overflows in any case. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/bb20d14d708ea174721e58bb53786b0521e4dd6d.1691757663.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: use cancelation match helper for poll and timeout requests

2023-07-17T16:05:48Z

Get rid of the request vs io_cancel_data checking and just use the exported helper for this. Signed-off-by: Jens Axboe

io_uring/timeout: always set 'ctx' in io_cancel_data

2023-07-17T16:05:48Z

In preparation for using a generic handler to match requests for cancelation purposes, ensure that ctx is set in io_cancel_data. The timeout handlers don't check for this as it'll always match, but we'll need it set going forward. Signed-off-by: Jens Axboe

io_uring: cleanup io_aux_cqe() API

2023-06-07T20:59:22Z

Everybody is passing in the request, so get rid of the io_ring_ctx and explicit user_data pass-in. Both the ctx and user_data can be deduced from the request at hand. Signed-off-by: Jens Axboe

io_uring: annotate offset timeout races

2023-05-20T01:56:56Z

It's racy to read ->cached_cq_tail without taking proper measures (usually grabbing ->completion_lock) as timeout requests with CQE offsets do, however they have never had a good semantics for from when they start counting. Annotate racy reads with data_race(). Reported-by: syzbot+cb265db2f3f3468ef436@syzkaller.appspotmail.com Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/4de3685e185832a92a572df2be2c735d2e21a83d.1684506056.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: add support for multishot timeouts

2023-04-19T01:38:36Z

A multishot timeout submission will repeatedly generate completions with the IORING_CQE_F_MORE cflag set. Depending on the value of the `off' field in the submission, these timeouts can either repeat indefinitely until cancelled (`off' = 0) or for a fixed number of times (`off' > 0). Only noseq timeouts (i.e. not dependent on the number of I/O completions) are supported. An indefinite timer will be cancelled if the CQ ever overflows. Signed-off-by: David Wei Link: https://lore.kernel.org/r/20230418225817.1905027-1-davidhwei@meta.com Signed-off-by: Jens Axboe

io_uring: encapsulate task_work state

2023-04-03T13:16:15Z

For task works we're passing around a bool pointer for whether the current ring is locked or not, let's wrap it in a structure, that will make it more opaque preventing abuse and will also help us to pass more info in the future if needed. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/1ecec9483d58696e248d1bfd52cf62b04442df1d.1679931367.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: ease timeout flush locking requirements

2022-12-14T15:53:35Z

We don't need completion_lock for timeout flushing, don't take it. Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/1e3dc657975ac445b80e7bdc40050db783a5935a.1670002973.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: revise completion_lock locking

2022-12-14T15:53:04Z

io_kill_timeouts() doesn't post any events but queues everything to task_work. Locking there is needed for protecting linked requests traversing, we should grab completion_lock directly instead of using io_cq_[un]lock helpers. Same goes for __io_req_find_next_prep(). Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/88e75d481a65dc295cb59722bb1cf76402d1c06b.1670002973.git.asml.silence@gmail.com Signed-off-by: Jens Axboe

io_uring: protect cq_timeouts with timeout_lock

2022-12-14T15:51:28Z

Read cq_timeouts in io_flush_timeouts() only after taking the timeout_lock, as it's protected by it. There are many places where we also grab ->completion_lock, but for instance io_timeout_fn() doesn't and still modifies cq_timeouts. Cc: stable@vger.kernel.org Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/9c79544dd6cf5c4018cb1bab99cf481a93ea46ef.1670002973.git.asml.silence@gmail.com Signed-off-by: Jens Axboe