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 -- Jens Axboe
