From 1c0d32fde5bdf1184bc274f864c09799278a1114 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sun, 4 Dec 2016 09:48:16 -0800 Subject: 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 Signed-off-by: David S. Miller --- net/netfilter/xt_RATEEST.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/netfilter/xt_RATEEST.c') diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c index dbd6c4a12b97..91a373a3f534 100644 --- a/net/netfilter/xt_RATEEST.c +++ b/net/netfilter/xt_RATEEST.c @@ -63,7 +63,7 @@ void xt_rateest_put(struct xt_rateest *est) mutex_lock(&xt_rateest_mutex); if (--est->refcnt == 0) { hlist_del(&est->list); - gen_kill_estimator(&est->bstats, &est->rstats); + gen_kill_estimator(&est->rate_est); /* * gen_estimator est_timer() might access est->lock or bstats, * wait a RCU grace period before freeing 'est' @@ -132,7 +132,7 @@ static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par) cfg.est.interval = info->interval; cfg.est.ewma_log = info->ewma_log; - ret = gen_new_estimator(&est->bstats, NULL, &est->rstats, + ret = gen_new_estimator(&est->bstats, NULL, &est->rate_est, &est->lock, NULL, &cfg.opt); if (ret < 0) goto err2; -- cgit v1.2.3