hi,
On 5/13/20 12:45 PM, Jens Axboe wrote:Hi Xiaoguang, Was doing some other testing today, and noticed a hang with fixed files. I did a bit of poor mans bisecting, and came up with this one: commit 0558955373023b08f638c9ede36741b0e4200f58 Author: Xiaoguang Wang <xiaoguang.wang@xxxxxxxxxxxxxxxxx> Date: Tue Mar 31 14:05:18 2020 +0800 io_uring: refactor file register/unregister/update handling If I revert this one, the test completes fine. The case case is pretty simple, just run t/io_uring from the fio repo, default settings: [ fio] # t/io_uring /dev/nvme0n1p2 Added file /dev/nvme0n1p2 sq_ring ptr = 0x0x7fe1cb81f000 sqes ptr = 0x0x7fe1cb81d000 cq_ring ptr = 0x0x7fe1cb81b000 polled=1, fixedbufs=1, buffered=0 QD=128, sq_ring=128, cq_ring=256 submitter=345 IOPS=240096, IOS/call=32/31, inflight=91 (91) IOPS=249696, IOS/call=32/31, inflight=99 (99) ^CExiting on signal 2 and ctrl-c it after a second or so. You'll then notice a kworker that is stuck in io_sqe_files_unregister(), here: /* wait for all refs nodes to complete */ wait_for_completion(&data->done); I'll try and debug this a bit, and for some reason it doens't trigger with the liburing fixed file setup. Just wanted to throw this out there, so if you have cycles, please do take a look at it.https://lore.kernel.org/io-uring/015659db-626c-5a78-6746-081a45175f45@xxxxxxxxx/T/#u
Thanks for this fix, and sorry, it's my bad, I didn't cover this case when sending patches. Can you share your test cases or test method when developing io_uring? Usually I just run test cases under liburing/test, seems it's not enough. Regards, Xiaoguang Wang
