From: Pavel Begunkov asml.silence@gmail.com
[ 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/f168b4f24181942f3614dd8ff648221736f572e6.165243374... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- fs/io_uring.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c index e0823f58f795..7272e410d24a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7327,6 +7327,8 @@ static void io_wq_submit_work(struct io_wq_work *work) * wait for request slots on the block side. */ if (!needs_poll) { + if (!(req->ctx->flags & IORING_SETUP_IOPOLL)) + break; cond_resched(); continue; }