Re: [PATCH 2/9] ublk: properly serialize all FETCH_REQs

[Jens Axboe <axboe@kernel.dk>]

On 4/14/25 1:58 PM, Uday Shankar wrote:
> +static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_device *ub,
> +		      struct ublk_queue *ubq, struct ublk_io *io,
> +		      const struct ublksrv_io_cmd *ub_cmd,
> +		      unsigned int issue_flags)
> +{
> +	int ret = 0;
> +
> +	if (issue_flags & IO_URING_F_NONBLOCK)
> +		return -EAGAIN;
> +
> +	mutex_lock(&ub->mutex);

This looks like overkill, if we can trylock the mutex that should surely
be fine? And I would imagine succeed most of the time, hence making the
inline/fastpath fine with F_NONBLOCK?

-- 
Jens Axboe