On 2/1/22 06:13, Niklas Cassel wrote:
> From: Niklas Cassel <niklas.cassel@xxxxxxx>
>
> To be able to report clat stats on a per priority granularity (instead of
> only high/low priority), we need to do ioprio_set(), and the matching
> td->ioprio assignment, before calling the io engine init callback.
>
> When a thread is using more than a single priority (e.g. option
> cmdprio_percentage is used), fio_cmdprio_init() will need to allocate and
> initialize an array that will hold the clat stats for all the different
> priorities that will be used by the struct td.
>
> For fio_cmdprio_init() to be able to initialize a per priority clat array
> properly, we need to assign td->ioprio before calling td_io_init().
>
> Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxx>
> ---
> backend.c | 21 +++++++++++----------
> 1 file changed, 11 insertions(+), 10 deletions(-)
>
> diff --git a/backend.c b/backend.c
> index c167f908..f7398b23 100644
> --- a/backend.c
> +++ b/backend.c
> @@ -1777,6 +1777,17 @@ static void *thread_main(void *data)
> if (!init_iolog(td))
> goto err;
>
> + /* ioprio_set() has to be done before td_io_init() */
> + if (fio_option_is_set(o, ioprio) ||
> + fio_option_is_set(o, ioprio_class)) {
> + ret = ioprio_set(IOPRIO_WHO_PROCESS, 0, o->ioprio_class, o->ioprio);
> + if (ret == -1) {
> + td_verror(td, errno, "ioprio_set");
> + goto err;
> + }
> + td->ioprio = ioprio_value(o->ioprio_class, o->ioprio);
> + }
> +
> if (td_io_init(td))
> goto err;
>
> @@ -1789,16 +1800,6 @@ static void *thread_main(void *data)
> if (o->verify_async && verify_async_init(td))
> goto err;
>
> - if (fio_option_is_set(o, ioprio) ||
> - fio_option_is_set(o, ioprio_class)) {
> - ret = ioprio_set(IOPRIO_WHO_PROCESS, 0, o->ioprio_class, o->ioprio);
> - if (ret == -1) {
> - td_verror(td, errno, "ioprio_set");
> - goto err;
> - }
> - td->ioprio = ioprio_value(o->ioprio_class, o->ioprio);
> - }
> -
> if (o->cgroup && cgroup_setup(td, cgroup_list, &cgroup_mnt))
> goto err;
>
Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
--
Damien Le Moal
Western Digital Research
