Re: [PATCH 3/3] block: introducing a bias over deadline's fifo_time

[Zhaoyang Huang]

On Fri, Feb 9, 2024 at 1:46 AM Bart Van Assche <bvanassche@xxxxxxx> wrote:
>
> On 2/8/24 01:31, zhaoyang.huang wrote:
> > diff --git a/block/mq-deadline.c b/block/mq-deadline.c
> > index f958e79277b8..43c08c3d6f18 100644
> > --- a/block/mq-deadline.c
> > +++ b/block/mq-deadline.c
> > @@ -15,6 +15,7 @@
> >   #include <linux/compiler.h>
> >   #include <linux/rbtree.h>
> >   #include <linux/sbitmap.h>
> > +#include "../kernel/sched/sched.h"
>
> Is kernel/sched/sched.h perhaps a private scheduler kernel header file? Shouldn't
> block layer code only include public scheduler header files?
>
> > @@ -840,7 +842,9 @@ static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
> >               /*
> >                * set expire time and add to fifo list
> >                */
> > -             rq->fifo_time = jiffies + dd->fifo_expire[data_dir];
> > +             fifo_expire = task_is_realtime(current) ? dd->fifo_expire[data_dir] :
> > +                     CFS_PROPORTION(current, dd->fifo_expire[data_dir]);
> > +             rq->fifo_time = jiffies + fifo_expire;
> >               insert_before = &per_prio->fifo_list[data_dir];
> >   #ifdef CONFIG_BLK_DEV_ZONED
> >               /*
>
> Making the mq-deadline request expiry time dependent on the task priority seems wrong
> to me.
But bio_set_ioprio has done this before
>
> Thanks,
>
> Bart.