From 8f6bac978640c1bf65a6462fcaf4e1e462676b17 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Fri, 13 May 2022 11:24:56 +0100 Subject: [PATCH] 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 Link: https://lore.kernel.org/r/f168b4f24181942f3614dd8ff648221736f572e6.1652433740.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/io_uring.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/io_uring.c b/fs/io_uring.c index a0680046ff3c..26bf488096b2 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -6939,6 +6939,8 @@ 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; }