On 3/16/24 02:24, Ming Lei wrote:
On Sat, Mar 16, 2024 at 10:04 AM Ming Lei <ming.lei@xxxxxxxxxx> wrote:
On Fri, Mar 15, 2024 at 04:53:21PM -0600, Jens Axboe wrote:
On Fri, 15 Mar 2024 15:29:50 +0000, Pavel Begunkov wrote:
Patch 1 is a fix.
Patches 2-7 are cleanups mainly dealing with issue_flags conversions,
misundertsandings of the flags and of the tw state. It'd be great to have
even without even w/o the rest.
8-11 mandate ctx locking for task_work and finally removes the CQE
caches, instead we post directly into the CQ. Note that the cache is
used by multishot auxiliary completions.
[...]
Applied, thanks!
Hi Jens and Pavel,
Looks this patch causes hang when running './check ublk/002' in blktests.
Not take close look, and I guess it hangs in
io_uring_cmd_del_cancelable() -> io_ring_submit_lock
Thanks, the trace doesn't completely explains it, but my blind spot
was io_uring_cmd_done() potentially grabbing the mutex. They're
supposed to be irq safe mimicking io_req_task_work_add(), that's how
nvme passthrough uses it as well (but at least it doesn't need the
cancellation bits).
One option is to replace it with a spinlock, the other is to delay
the io_uring_cmd_del_cancelable() call to the task_work callback.
The latter would be cleaner and more preferable, but I'm lacking
context to tell if that would be correct. Ming, what do you think?
--
Pavel Begunkov
