tree 9815be0817acb9c61cef211be806f7ea4d611041
parent 79dca1846fe979304ad0b998e56b20326e2e5a72
author Jens Axboe <axboe@kernel.dk> 1629387702 -0600
committer Jens Axboe <axboe@kernel.dk> 1629745843 -0600

io_uring: add comments on why PF_EXITING checking is safe

We have two checks of task->flags & PF_EXITING left:

1) In io_req_task_submit(), which is called in task_work and hence always
   in the context of the original task. That means that
   req->task == current, and hence checking ->flags is totally fine.

2) In io_poll_rewait(), where we need to stop re-arming poll to prevent
   it interfering with cancelation. This is only run from task_work as
   well, and hence for this case too req->task == current.

Add a comment to both spots detailing that.

Signed-off-by: Jens Axboe <axboe@kernel.dk>