netdev - [PATCH net-next] netfilter: xt_rateest_put() can directly call kfree()

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Date:   Tue, 06 Dec 2016 09:30:02 -0800
From:   Eric Dumazet <eric.dumazet@...il.com>
To:     David Miller <davem@...emloft.net>
Cc:     netdev <netdev@...r.kernel.org>,
        Pablo Neira Ayuso <pablo@...filter.org>,
        Florian Westphal <fw@...len.de>
Subject: [PATCH net-next] netfilter: xt_rateest_put() can directly call
 kfree()

From: Eric Dumazet <edumazet@...gle.com>

After commit 1c0d32fde5bd ("net_sched: gen_estimator: complete rewrite
of rate estimators") we no longer have to respect an RCU grace period
after calling gen_kill_estimator()

Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 include/net/netfilter/xt_rateest.h |    1 -
 net/netfilter/xt_RATEEST.c         |    6 +-----
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/include/net/netfilter/xt_rateest.h b/include/net/netfilter/xt_rateest.h
index 130e58361f998ecdf361910b196e69778224d955..76c9347c3645f86d55696126909f9898a6f41594 100644
--- a/include/net/netfilter/xt_rateest.h
+++ b/include/net/netfilter/xt_rateest.h
@@ -14,7 +14,6 @@ struct xt_rateest {
 	struct hlist_node		list;
 	char				name[IFNAMSIZ];
 	struct gnet_estimator		params;
-	struct rcu_head			rcu;
 
 	/* keep this field far away to speedup xt_rateest_mt() */
 	struct net_rate_estimator __rcu *rate_est;
diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c
index 91a373a3f534de8d8641341c33c08d8fc49cbd29..e534648aa516a86aba29b741378160a37e5b9dcb 100644
--- a/net/netfilter/xt_RATEEST.c
+++ b/net/netfilter/xt_RATEEST.c
@@ -64,11 +64,7 @@ void xt_rateest_put(struct xt_rateest *est)
 	if (--est->refcnt == 0) {
 		hlist_del(&est->list);
 		gen_kill_estimator(&est->rate_est);
-		/*
-		 * gen_estimator est_timer() might access est->lock or bstats,
-		 * wait a RCU grace period before freeing 'est'
-		 */
-		kfree_rcu(est, rcu);
+		kfree(est);
 	}
 	mutex_unlock(&xt_rateest_mutex);
 }