Commit 62977281 authored Apr 24, 2019 by Stefan Bühler Committed by Jens Axboe Apr 30, 2019

io_uring: remove unnecessary barrier after unsetting IORING_SQ_NEED_WAKEUP



There is no operation to order with afterwards, and removing the flag is
not critical in any way.

There will always be a "race condition" where the application will
trigger IORING_ENTER_SQ_WAKEUP when it isn't actually needed.

Signed-off-by: Stefan Bühler <source@stbuehler.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent b841f195

fs/io_uring.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -1969,13 +1969,11 @@ static int io_sq_thread(void *data)
		finish_wait(&ctx->sqo_wait, &wait);

		ctx->sq_ring->flags &= ~IORING_SQ_NEED_WAKEUP;
		smp_wmb();
		continue;
		}
		finish_wait(&ctx->sqo_wait, &wait);

		ctx->sq_ring->flags &= ~IORING_SQ_NEED_WAKEUP;
		smp_wmb();
		}

		i = 0;

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