block: add polled wakeup task helper
If we're polling for IO on a device that doesn't use interrupts, then
IO completion loop (and wake of task) is done by submitting task itself.
If that is the case, then we don't need to enter the wake_up_process()
function, we can simply mark ourselves as TASK_RUNNING.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index c039abf..9fe5667 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -181,7 +181,7 @@ static void blkdev_bio_end_io_simple(struct bio *bio)
struct task_struct *waiter = bio->bi_private;
WRITE_ONCE(bio->bi_private, NULL);
- wake_up_process(waiter);
+ blk_wake_io_task(waiter);
}
static ssize_t
@@ -305,7 +305,7 @@ static void blkdev_bio_end_io(struct bio *bio)
struct task_struct *waiter = dio->waiter;
WRITE_ONCE(dio->waiter, NULL);
- wake_up_process(waiter);
+ blk_wake_io_task(waiter);
}
}