diff options
| author | Simon Horman <horms@verge.net.au> | 2013-05-22 14:50:32 +0900 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-05-23 14:23:18 +0200 |
| commit | a38e5e230e3f4e7bc9195d3e7a81567c888257ca (patch) | |
| tree | 4535af1dfe823da8100ae291a19155dbc70669e5 | |
| parent | f6f3c437d09e2f62533034e67bfb4385191e992c (diff) | |
ipvs: use cond_resched_rcu() helper when walking connections
This avoids the situation where walking of a large number of connections
may prevent scheduling for a long time while also avoiding excessive
calls to rcu_read_unlock() and rcu_read_lock().
Note that in the case of !CONFIG_PREEMPT_RCU this will
add a call to cond_resched().
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | net/netfilter/ipvs/ip_vs_conn.c | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index a083bda322b6..c8c52a98590b 100644 --- a/net/netfilter/ipvs/ip_vs_conn.c +++ b/net/netfilter/ipvs/ip_vs_conn.c @@ -975,8 +975,7 @@ static void *ip_vs_conn_array(struct seq_file *seq, loff_t pos) return cp; } } - rcu_read_unlock(); - rcu_read_lock(); + cond_resched_rcu(); } return NULL; @@ -1015,8 +1014,7 @@ static void *ip_vs_conn_seq_next(struct seq_file *seq, void *v, loff_t *pos) iter->l = &ip_vs_conn_tab[idx]; return cp; } - rcu_read_unlock(); - rcu_read_lock(); + cond_resched_rcu(); } iter->l = NULL; return NULL; @@ -1206,17 +1204,13 @@ void ip_vs_random_dropentry(struct net *net) int idx; struct ip_vs_conn *cp, *cp_c; + rcu_read_lock(); /* * Randomly scan 1/32 of the whole table every second */ for (idx = 0; idx < (ip_vs_conn_tab_size>>5); idx++) { unsigned int hash = net_random() & ip_vs_conn_tab_mask; - /* - * Lock is actually needed in this loop. - */ - rcu_read_lock(); - hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[hash], c_list) { if (cp->flags & IP_VS_CONN_F_TEMPLATE) /* connection template */ @@ -1252,8 +1246,9 @@ void ip_vs_random_dropentry(struct net *net) __ip_vs_conn_put(cp); } } - rcu_read_unlock(); + cond_resched_rcu(); } + rcu_read_unlock(); } @@ -1267,11 +1262,8 @@ static void ip_vs_conn_flush(struct net *net) struct netns_ipvs *ipvs = net_ipvs(net); flush_again: + rcu_read_lock(); for (idx = 0; idx < ip_vs_conn_tab_size; idx++) { - /* - * Lock is actually needed in this loop. - */ - rcu_read_lock(); hlist_for_each_entry_rcu(cp, &ip_vs_conn_tab[idx], c_list) { if (!ip_vs_conn_net_eq(cp, net)) @@ -1286,8 +1278,9 @@ flush_again: __ip_vs_conn_put(cp); } } - rcu_read_unlock(); + cond_resched_rcu(); } + rcu_read_unlock(); /* the counter may be not NULL, because maybe some conn entries are run by slow timer handler or unhashed but still referred */ |