diff options
author | Eric Dumazet <edumazet@google.com> | 2016-12-04 09:48:16 -0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2016-12-05 15:21:59 -0500 |
commit | 1c0d32fde5bdf1184bc274f864c09799278a1114 (patch) | |
tree | 47367d46dfc125e19294c3f5fa9a021520bd5660 /net/sched/sch_htb.c | |
parent | a6e169312971219a34927e8fdece60046fafb8ba (diff) |
net_sched: gen_estimator: complete rewrite of rate estimators
1) Old code was hard to maintain, due to complex lock chains.
(We probably will be able to remove some kfree_rcu() in callers)
2) Using a single timer to update all estimators does not scale.
3) Code was buggy on 32bit kernel (WRITE_ONCE() on 64bit quantity
is not supposed to work well)
In this rewrite :
- I removed the RB tree that had to be scanned in
gen_estimator_active(). qdisc dumps should be much faster.
- Each estimator has its own timer.
- Estimations are maintained in net_rate_estimator structure,
instead of dirtying the qdisc. Minor, but part of the simplification.
- Reading the estimator uses RCU and a seqcount to provide proper
support for 32bit kernels.
- We reduce memory need when estimators are not used, since
we store a pointer, instead of the bytes/packets counters.
- xt_rateest_mt() no longer has to grab a spinlock.
(In the future, xt_rateest_tg() could be switched to per cpu counters)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched/sch_htb.c')
-rw-r--r-- | net/sched/sch_htb.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c index 9926fe4f3b6f..760f39e7caee 100644 --- a/net/sched/sch_htb.c +++ b/net/sched/sch_htb.c @@ -111,7 +111,7 @@ struct htb_class { unsigned int children; struct htb_class *parent; /* parent class */ - struct gnet_stats_rate_est64 rate_est; + struct net_rate_estimator __rcu *rate_est; /* * Written often fields @@ -1145,7 +1145,7 @@ htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, struct gnet_dump *d) if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch), d, NULL, &cl->bstats) < 0 || - gnet_stats_copy_rate_est(d, &cl->bstats, &cl->rate_est) < 0 || + gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || gnet_stats_copy_queue(d, NULL, &qs, qlen) < 0) return -1; @@ -1228,7 +1228,7 @@ static void htb_destroy_class(struct Qdisc *sch, struct htb_class *cl) WARN_ON(!cl->un.leaf.q); qdisc_destroy(cl->un.leaf.q); } - gen_kill_estimator(&cl->bstats, &cl->rate_est); + gen_kill_estimator(&cl->rate_est); tcf_destroy_chain(&cl->filter_list); kfree(cl); } |