io_uring: remove the per-ctx fallback task_work machinery

With the tctx fallback running its entries directly, the per-ctx
fallback work has a single user left: moving local (DEFER_TASKRUN)
task_work entries out of a ring that is going away. Both of its call
sites are process context and don't hold ->uring_lock, the same
conditions the deferred fallback work itself ran under - so run the
entries in cancel mode right there instead, and rename the helper to
io_cancel_local_task_work() to match what it now does.

With that, ->fallback_llist, ->fallback_work, io_fallback_req_func()
and __io_fallback_tw() can all go away, along with the fallback work
flushing in the ring exit and cancel paths. Requests that get
orphaned by an exiting task now run via the tctx fallback work, which
the ring exit side implicitly waits on through the ctx refs those
requests hold.

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

0 files changed, 0 insertions, 0 deletions