io_uring: fix an issue when IOSQE_IO_LINK is inserted into defer list
This patch may fix two issues:
First, when IOSQE_IO_DRAIN set, the next IOs need to be inserted into
defer list to delay execution, but link io will be actively scheduled to
run by calling io_queue_sqe.
Second, when multiple LINK_IOs are inserted together with defer_list,
the LINK_IO is no longer keep order.
|-------------|
| LINK_IO | ----> insert to defer_list -----------
|-------------| |
| LINK_IO | ----> insert to defer_list ----------|
|-------------| |
| LINK_IO | ----> insert to defer_list ----------|
|-------------| |
| NORMAL_IO | ----> insert to defer_list ----------|
|-------------| |
|
queue_work at same time <-----|
Fixes: 9e645e1105c ("io_uring: add support for sqe links")
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 file changed
