As per RFC 8033, it is sufficient for the drop probability
decay factor to have a value of (1 - 1/64) instead of 98%.
This avoids the need to do slow division.
Suggested-by: David Laight <david.lai...@aculab.com>
Signed-off-by: Leslie Monis <lesliemo...@gmail.com>
---
net/sched/sch_pie.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/sched/sch_pie.c b/net/sched/sch_pie.c
index f93cfe034c72..1cc0c7b74aa3 100644
--- a/net/sched/sch_pie.c
+++ b/net/sched/sch_pie.c
@@ -429,7 +429,8 @@ static void calculate_probability(struct Qdisc *sch)
*/
if (qdelay == 0 && qdelay_old == 0 && update_prob)
- q->vars.prob = 98 * div_u64(q->vars.prob, 100);
+ /* Reduce drop probability to 98.4% */
+ q->vars.prob -= q->vars.prob / 64u;
q->vars.qdelay = qdelay;
q->vars.qlen_old = qlen;
--
2.17.1
