On 6/21/22 19:24, Jan Kara wrote:
> get_current_ioprio() operates only on current task. We will need the
> same functionality for other tasks as well. Generalize
> get_current_ioprio() for that and also move the bulk out of the header
> file because it is large enough.
>
> Signed-off-by: Jan Kara <jack@xxxxxxx>
Looks OK to me.
Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
> ---
> block/ioprio.c | 26 ++++++++++++++++++++++++++
> include/linux/ioprio.h | 26 ++++++++++----------------
> 2 files changed, 36 insertions(+), 16 deletions(-)
>
> diff --git a/block/ioprio.c b/block/ioprio.c
> index 2a34cbca18ae..c4e3476155a1 100644
> --- a/block/ioprio.c
> +++ b/block/ioprio.c
> @@ -138,6 +138,32 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio)
> return ret;
> }
>
> +/*
> + * If the task has set an I/O priority, use that. Otherwise, return
> + * the default I/O priority.
> + *
> + * Expected to be called for current task or with task_lock() held to keep
> + * io_context stable.
> + */
> +int __get_task_ioprio(struct task_struct *p)
> +{
> + struct io_context *ioc = p->io_context;
> + int prio;
> +
> + if (p != current)
> + lockdep_assert_held(&p->alloc_lock);
> + if (ioc)
> + prio = ioc->ioprio;
> + else
> + prio = IOPRIO_DEFAULT;
> +
> + if (IOPRIO_PRIO_CLASS(prio) == IOPRIO_CLASS_NONE)
> + prio = IOPRIO_PRIO_VALUE(task_nice_ioclass(p),
> + task_nice_ioprio(p));
> + return prio;
> +}
> +EXPORT_SYMBOL_GPL(__get_task_ioprio);
> +
> static int get_task_ioprio(struct task_struct *p)
> {
> int ret;
> diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h
> index 61ed6bb4998e..788a8ff57068 100644
> --- a/include/linux/ioprio.h
> +++ b/include/linux/ioprio.h
> @@ -46,24 +46,18 @@ static inline int task_nice_ioclass(struct task_struct *task)
> return IOPRIO_CLASS_BE;
> }
>
> -/*
> - * If the calling process has set an I/O priority, use that. Otherwise, return
> - * the default I/O priority.
> - */
> -static inline int get_current_ioprio(void)
> +#ifdef CONFIG_BLOCK
> +int __get_task_ioprio(struct task_struct *p);
> +#else
> +static inline int __get_task_ioprio(int ioprio)
> {
> - struct io_context *ioc = current->io_context;
> - int prio;
> -
> - if (ioc)
> - prio = ioc->ioprio;
> - else
> - prio = IOPRIO_DEFAULT;
> + return IOPRIO_DEFAULT;
> +}
> +#endif /* CONFIG_BLOCK */
>
> - if (IOPRIO_PRIO_CLASS(prio) == IOPRIO_CLASS_NONE)
> - prio = IOPRIO_PRIO_VALUE(task_nice_ioclass(current),
> - task_nice_ioprio(current));
> - return prio;
> +static inline int get_current_ioprio(void)
> +{
> + return __get_task_ioprio(current);
> }
>
> /*
--
Damien Le Moal
Western Digital Research
