On 1/16/21 4:37 PM, Pavel Begunkov wrote:
> If there are no requests at the time __io_uring_task_cancel() is called,
> tctx_inflight() returns zero and and it terminates not getting a chance
> to go through __io_uring_files_cancel() and do
> io_disable_sqo_submit(). And we absolutely want them disabled by the
> time cancellation ends.
>
> Also a fix potential false positive warning because of ctx->sq_data
> check before io_disable_sqo_submit().
>
> Reported-by: Jens Axboe <axboe@xxxxxxxxx>
> Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
> ---
>
> To not grow diffstat now will be cleaned for-next
>
> fs/io_uring.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index d494c4269fc5..0d50845f1f3f 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -8937,10 +8937,12 @@ static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
> {
> struct task_struct *task = current;
>
> - if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
> + if (ctx->flags & IORING_SETUP_SQPOLL) {
> /* for SQPOLL only sqo_task has task notes */
> WARN_ON_ONCE(ctx->sqo_task != current);
> io_disable_sqo_submit(ctx);
> + }
> + if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
> task = ctx->sq_data->thread;
> atomic_inc(&task->io_uring->in_idle);
> io_sq_thread_park(ctx->sq_data);
Maybe just nest that inside?
if (ctx->flags & IORING_SETUP_SQPOLL) {
/* for SQPOLL only sqo_task has task notes */
WARN_ON_ONCE(ctx->sqo_task != current);
io_disable_sqo_submit(ctx);
if (ctx->sq_data) {
...
}
}
That'd look a bit cleaner imho.
--
Jens Axboe
