net: sched: refactor flower walk to iterate over idr
Extend struct tcf_walker with additional 'cookie' field. It is intended to
be used by classifier walk implementations to continue iteration directly
from particular filter, instead of iterating 'skip' number of times.
Change flower walk implementation to save filter handle in 'cookie'. Each
time flower walk is called, it looks up filter with saved handle directly
with idr, instead of iterating over filter linked list 'skip' number of
times. This change improves complexity of dumping flower classifier from
quadratic to linearithmic. (assuming idr lookup has logarithmic complexity)
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reported-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 73d9967..c51b1b1 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1508,7 +1508,9 @@ static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
arg.w.stop = 0;
arg.w.skip = cb->args[1] - 1;
arg.w.count = 0;
+ arg.w.cookie = cb->args[2];
tp->ops->walk(tp, &arg.w);
+ cb->args[2] = arg.w.cookie;
cb->args[1] = arg.w.count + 1;
if (arg.w.stop)
return false;