On 10/27/19 10:49 AM, Jens Axboe wrote: > On 10/27/19 10:44 AM, Pavel Begunkov wrote: >> On 27/10/2019 19:32, Jens Axboe wrote: >>> On 10/27/19 9:35 AM, Pavel Begunkov wrote: >>>> A small cleanup of very similar but diverged io_submit_sqes() and >>>> io_ring_submit() >>>> >>>> Pavel Begunkov (2): >>>> io_uring: handle mm_fault outside of submission >>>> io_uring: merge io_submit_sqes and io_ring_submit >>>> >>>> fs/io_uring.c | 116 ++++++++++++++------------------------------------ >>>> 1 file changed, 33 insertions(+), 83 deletions(-) >>> >>> I like the cleanups here, but one thing that seems off is the >>> assumption that io_sq_thread() always needs to grab the mm. If >>> the sqes processed are just READ/WRITE_FIXED, then it never needs >>> to grab the mm. >>> Yeah, we removed it to fix bugs. Personally, I think it would be >> clearer to do lazy grabbing conditionally, rather than have two >> functions. And in this case it's easier to do after merging. >> >> Do you prefer to return it back first? > > Ah I see, no I don't care about that. OK, looked at the post-patches state. It's still not correct. You are grabbing the mm from io_sq_thread() unconditionally. We should not do that, only if the sqes we need to submit need mm context. -- Jens Axboe
