From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Subject: [PATCH v3 2/2] ipvs: Use cond_resched_rcu_lock() helper when dumping connections Date: Wed, 1 May 2013 17:57:53 +0900 Message-ID: <1367398673-1253-3-git-send-email-horms@verge.net.au> References: <1367398673-1253-1-git-send-email-horms@verge.net.au> Cc: lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, linux-kernel@vger.kernel.org, Pablo Neira Ayuso , Dipankar Sarma , Simon Horman , Ingo Molnar To: Eric Dumazet , Julian Anastasov , Ingo Molnar , Peter Zijlstra , "Paul E. McKenney" Return-path: In-Reply-To: <1367398673-1253-1-git-send-email-horms@verge.net.au> Sender: netfilter-devel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org This avoids the situation where a dump 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(). Compile tested only. Cc: Eric Dumazet Cc: Julian Anastasov Cc: Ingo Molnar Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_conn.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index a083bda..42a7b33 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_lock(); } 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_lock(); } iter->l = NULL; return NULL; -- 1.8.2.1