Hi,
Jakub Kicinski <jakub.kicin...@netronome.com> writes:
> Recent changes to taprio did not use the correct div64 helpers,
> leading to:
>
> net/sched/sch_taprio.o: In function `taprio_dequeue':
> sch_taprio.c:(.text+0x34a): undefined reference to `__divdi3'
> net/sched/sch_taprio.o: In function `advance_sched':
> sch_taprio.c:(.text+0xa0b): undefined reference to `__divdi3'
> net/sched/sch_taprio.o: In function `taprio_init':
> sch_taprio.c:(.text+0x1450): undefined reference to `__divdi3'
> /home/jkicinski/devel/linux/Makefile:1032: recipe for target 'vmlinux' failed
>
> Use math64 helpers.
>
> Fixes: 7b9eba7ba0c1 ("net/sched: taprio: fix picos_per_byte miscalculation")
> Signed-off-by: Jakub Kicinski <jakub.kicin...@netronome.com>
> Reviewed-by: Dirk van der Merwe <dirk.vanderme...@netronome.com>
Acked-by: Leandro Dorileo <leandro.maciel.dori...@intel.com>
> ---
> CC: Leandro Dorileo <leandro.maciel.dori...@intel.com>
> CC: Vinicius Costa Gomes <vinicius.go...@intel.com>
>
> net/sched/sch_taprio.c | 17 +++++++++++------
> 1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/net/sched/sch_taprio.c b/net/
> sched/sch_taprio.c
> index 1b0fb80162e6..001182aa3959 100644
> --- a/net/sched/sch_taprio.c
> +++ b/net/sched/sch_taprio.c
> @@ -13,6 +13,7 @@
> #include <linux/list.h>
> #include <linux/errno.h>
> #include <linux/skbuff.h>
> +#include <linux/math64.h>
> #include <linux/module.h>
> #include <linux/spinlock.h>
> #include <net/netlink.h>
> @@ -121,7 +122,14 @@ static struct sk_buff *taprio_peek(struct Qdisc *sch)
>
> static inline int length_to_duration(struct taprio_sched *q, int len)
> {
> - return (len * atomic64_read(&q->picos_per_byte)) / 1000;
> + return div_u64(len * atomic64_read(&q->picos_per_byte), 1000);
> +}
> +
> +static void taprio_set_budget(struct taprio_sched *q, struct sched_entry
> *entry)
> +{
> + atomic_set(&entry->budget,
> + div64_u64((u64)entry->interval * 1000,
> + atomic64_read(&q->picos_per_byte)));
> }
>
> static struct sk_buff *taprio_dequeue(struct Qdisc *sch)
> @@ -241,8 +249,7 @@ static enum hrtimer_restart advance_sched(struct hrtimer
> *timer)
> close_time = k
> time_add_ns(entry->close_time, next->interval);
>
> next->close_time = close_time;
> - atomic_set(&next->budget,
> - (next->interval * 1000) / atomic64_read(&q->picos_per_byte));
> + taprio_set_budget(q, next);
>
> first_run:
> rcu_assign_pointer(q->current_entry, next);
> @@ -575,9 +582,7 @@ static void taprio_start_sched(struct Qdisc *sch, ktime_t
> start)
> list);
>
> first->close_time = ktime_add_ns(start, first->interval);
> - atomic_set(&first->budget,
> - (first->interval * 1000) /
> - atomic64_read(&q->picos_per_byte));
> + taprio_set_budget(q, first);
> rcu_assign_pointer(q->current_entry, NULL);
>
> spin_unlock_irqrestore(&q->current_entry_lock, flags);
> --
> 2.21.0
