On 1/19/21 10:38 AM, Pavel Begunkov wrote: > On 19/01/2021 01:58, Joseph Qi wrote: >>> Hmm, I hastened, for files we need IO_WQ_WORK_FILES, >>> +IO_WQ_WORK_BLKCG for same reasons. needs_file would make >>> it to grab a struct file, that is wrong. >>> Probably worked out because it just grabbed fd=0/stdin. >>> >> >> I think IO_WQ_WORK_FILES can work since it will acquire >> files when initialize async cancel request. > > That the one controlling files in the first place, need_file > just happened to grab them submission. > >> Don't quite understand why we should have IO_WQ_WORK_BLKCG. > > Because it's set for IORING_OP_CLOSE, and similar situation > may happen but with async_cancel from io-wq. > So how about do switch and restore in io_run_cancel(), seems it can take care of direct request, sqthread and io-wq cases. Thanks, Joseph > Actually, it's even nastier than that, and neither of io_op_def > flags would work because for io-wq case you can end up doing > close() with different from original files. I'll think how it > can be done tomorrow. >
