From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ding Tianhong Subject: [PATCH net-next v4 1/6] bonding: simplify and use RCU protection for 3ad xmit path Date: Fri, 6 Sep 2013 15:28:07 +0800 Message-ID: <52298407.9040103@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit To: Jay Vosburgh , Andy Gospodarek , "David S. Miller" , Nikolay Aleksandrov , Veaceslav Falico , Netdev Return-path: Received: from szxga01-in.huawei.com ([119.145.14.64]:24577 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750721Ab3IFH22 (ORCPT ); Fri, 6 Sep 2013 03:28:28 -0400 Sender: netdev-owner@vger.kernel.org List-ID: The commit 278b20837511776dc9d5f6ee1c7fabd5479838bb (bonding: initial RCU conversion) has convert the roundrobin, active-backup, broadcast and xor xmit path to rcu protection, the performance will be better for these mode, so this time, convert xmit path for 3ad mode. Suggested-by: Nikolay Aleksandrov Suggested-by: Veaceslav Falico Signed-off-by: Ding Tianhong Signed-off-by: Wang Yufen Cc: Nikolay Aleksandrov Cc: Veaceslav Falico --- drivers/net/bonding/bond_3ad.c | 32 ++++++++++++++------------------ drivers/net/bonding/bonding.h | 33 ++++++++++++++++++++++++++++++++- 2 files changed, 46 insertions(+), 19 deletions(-) diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index 0d8f427..13f1deb 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -143,7 +143,7 @@ static inline struct bonding *__get_bond_by_port(struct port *port) */ static inline struct port *__get_first_port(struct bonding *bond) { - struct slave *first_slave = bond_first_slave(bond); + struct slave *first_slave = bond_first_slave_rcu(bond); return first_slave ? &(SLAVE_AD_INFO(first_slave).port) : NULL; } @@ -163,7 +163,7 @@ static inline struct port *__get_next_port(struct port *port) // If there's no bond for this port, or this is the last slave if (bond == NULL) return NULL; - slave_next = bond_next_slave(bond, slave); + slave_next = bond_next_slave_rcu(bond, slave); if (!slave_next || bond_is_first_slave(bond, slave_next)) return NULL; @@ -2417,16 +2417,14 @@ int bond_3ad_get_active_agg_info(struct bonding *bond, struct ad_info *ad_info) int bond_3ad_xmit_xor(struct sk_buff *skb, struct net_device *dev) { - struct slave *slave, *start_at; struct bonding *bond = netdev_priv(dev); + struct slave *slave; int slave_agg_no; int slaves_in_agg; int agg_id; - int i; struct ad_info ad_info; int res = 1; - read_lock(&bond->lock); if (__bond_3ad_get_active_agg_info(bond, &ad_info)) { pr_debug("%s: Error: __bond_3ad_get_active_agg_info failed\n", dev->name); @@ -2444,13 +2442,17 @@ int bond_3ad_xmit_xor(struct sk_buff *skb, struct net_device *dev) slave_agg_no = bond->xmit_hash_policy(skb, slaves_in_agg); - bond_for_each_slave(bond, slave) { + bond_for_each_slave_rcu(bond, slave) { struct aggregator *agg = SLAVE_AD_INFO(slave).port.aggregator; if (agg && (agg->aggregator_identifier == agg_id)) { - slave_agg_no--; - if (slave_agg_no < 0) - break; + if (--slave_agg_no < 0) { + if (SLAVE_IS_OK(slave)) { + res = bond_dev_queue_xmit(bond, + skb, slave->dev); + goto out; + } + } } } @@ -2460,23 +2462,17 @@ int bond_3ad_xmit_xor(struct sk_buff *skb, struct net_device *dev) goto out; } - start_at = slave; - - bond_for_each_slave_from(bond, slave, i, start_at) { - int slave_agg_id = 0; + bond_for_each_slave_rcu(bond, slave) { struct aggregator *agg = SLAVE_AD_INFO(slave).port.aggregator; - if (agg) - slave_agg_id = agg->aggregator_identifier; - - if (SLAVE_IS_OK(slave) && agg && (slave_agg_id == agg_id)) { + if (SLAVE_IS_OK(slave) && agg && + agg->aggregator_identifier == agg_id) { res = bond_dev_queue_xmit(bond, skb, slave->dev); break; } } out: - read_unlock(&bond->lock); if (res) { /* no suitable interface, frame not sent */ kfree_skb(skb); diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h index f7ab161..419161d 100644 --- a/drivers/net/bonding/bonding.h +++ b/drivers/net/bonding/bonding.h @@ -74,13 +74,35 @@ /* slave list primitives */ #define bond_to_slave(ptr) list_entry(ptr, struct slave, list) +/* slave list primitives, Caller must hold rcu_read_lock */ +#define bond_to_slave_rcu(ptr) list_entry_rcu(ptr, struct slave, list) + +/* bond_is_empty return NULL if slave list is empty*/ +#define bond_is_empty(bond) \ + (list_empty(&(bond)->slave_list)) + +/* bond_is_empty_rcu return NULL if slave list is empty*/ +#define bond_is_empty_rcu(bond) \ + (!list_first_or_null_rcu(&(bond)->slave_list, struct slave, list)) + /* IMPORTANT: bond_first/last_slave can return NULL in case of an empty list */ #define bond_first_slave(bond) \ list_first_entry_or_null(&(bond)->slave_list, struct slave, list) #define bond_last_slave(bond) \ - (list_empty(&(bond)->slave_list) ? NULL : \ + (bond_is_empty(bond) ? NULL : \ bond_to_slave((bond)->slave_list.prev)) +/** + * IMPORTANT: bond_first/last_slave_rcu can return NULL in case of an empty list + * Caller must hold rcu_read_lock + */ +#define bond_first_slave_rcu(bond) \ + (bond_is_empty_rcu(bond) ? NULL : \ + bond_to_slave_rcu((bond)->slave_list.next)) +#define bond_last_slave_rcu(bond) \ + (bond_is_empty_rcu(bond) ? NULL : \ + bond_to_slave_rcu((bond)->slave_list.prev)) + #define bond_is_first_slave(bond, pos) ((pos)->list.prev == &(bond)->slave_list) #define bond_is_last_slave(bond, pos) ((pos)->list.next == &(bond)->slave_list) @@ -93,6 +115,15 @@ (bond_is_first_slave(bond, pos) ? bond_last_slave(bond) : \ bond_to_slave((pos)->list.prev)) +/* Since bond_first/last_slave_rcu can return NULL, these can return NULL too */ +#define bond_next_slave_rcu(bond, pos) \ + (bond_is_last_slave(bond, pos) ? bond_first_slave_rcu(bond) : \ + bond_to_slave_rcu((pos)->list.next)) + +#define bond_prev_slave_rcu(bond, pos) \ + (bond_is_first_slave(bond, pos) ? bond_last_slave_rcu(bond) : \ + bond_to_slave_rcu((pos)->list.prev)) + /** * bond_for_each_slave_from - iterate the slaves list from a starting point * @bond: the bond holding this list. -- 1.8.2.1