io_uring: avoid io-wq -EAGAIN looping for !IOPOLL
authorPavel Begunkov <asml.silence@gmail.com>
Fri, 13 May 2022 10:24:56 +0000 (11:24 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 12 Jul 2022 14:35:08 +0000 (16:35 +0200)
commit51ebf1b6a077fb2c54eae28ff765c299833193ee
treeb3f2d68d7f6e309395c94c3d844a9511eaac516c
parentb3cec8a42fcd11d05313c724f27e01b1db77522c
io_uring: avoid io-wq -EAGAIN looping for !IOPOLL

[ Upstream commit e0deb6a025ae8c850dc8685be39fb27b06c88736 ]

If an opcode handler semi-reliably returns -EAGAIN, io_wq_submit_work()
might continue busily hammer the same handler over and over again, which
is not ideal. The -EAGAIN handling in question was put there only for
IOPOLL, so restrict it to IOPOLL mode only where there is no other
recourse than to retry as we cannot wait.

Fixes: def596e9557c9 ("io_uring: support for IO polling")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f168b4f24181942f3614dd8ff648221736f572e6.1652433740.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
fs/io_uring.c