From 85168c0036fadf3657470b93cd9babeee8d123d7 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Wed, 16 Jan 2013 16:05:06 +0800 Subject: [PATCH] xfrm: replace rwlock on xfrm_km_list with rcu Cc: Steffen Klassert Cc: Herbert Xu Cc: "David S. Miller" Signed-off-by: Cong Wang Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_state.c | 58 ++++++++++++++++++++++--------------------- 1 file changed, 30 insertions(+), 28 deletions(-) diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index 64780a6f7b86..1522f19f273a 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -1644,27 +1644,26 @@ static void xfrm_replay_timer_handler(unsigned long data) } static LIST_HEAD(xfrm_km_list); -static DEFINE_RWLOCK(xfrm_km_lock); void km_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c) { struct xfrm_mgr *km; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) if (km->notify_policy) km->notify_policy(xp, dir, c); - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); } void km_state_notify(struct xfrm_state *x, const struct km_event *c) { struct xfrm_mgr *km; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) if (km->notify) km->notify(x, c); - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); } EXPORT_SYMBOL(km_policy_notify); @@ -1694,13 +1693,13 @@ int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol) int err = -EINVAL, acqret; struct xfrm_mgr *km; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) { + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) { acqret = km->acquire(x, t, pol); if (!acqret) err = acqret; } - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); return err; } EXPORT_SYMBOL(km_query); @@ -1710,14 +1709,14 @@ int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport) int err = -EINVAL; struct xfrm_mgr *km; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) { + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) { if (km->new_mapping) err = km->new_mapping(x, ipaddr, sport); if (!err) break; } - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); return err; } EXPORT_SYMBOL(km_new_mapping); @@ -1746,15 +1745,15 @@ int km_migrate(const struct xfrm_selector *sel, u8 dir, u8 type, int ret; struct xfrm_mgr *km; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) { + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) { if (km->migrate) { ret = km->migrate(sel, dir, type, m, num_migrate, k); if (!ret) err = ret; } } - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); return err; } EXPORT_SYMBOL(km_migrate); @@ -1766,15 +1765,15 @@ int km_report(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address int ret; struct xfrm_mgr *km; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) { + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) { if (km->report) { ret = km->report(net, proto, sel, addr); if (!ret) err = ret; } } - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); return err; } EXPORT_SYMBOL(km_report); @@ -1798,14 +1797,14 @@ int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen goto out; err = -EINVAL; - read_lock(&xfrm_km_lock); - list_for_each_entry(km, &xfrm_km_list, list) { + rcu_read_lock(); + list_for_each_entry_rcu(km, &xfrm_km_list, list) { pol = km->compile_policy(sk, optname, data, optlen, &err); if (err >= 0) break; } - read_unlock(&xfrm_km_lock); + rcu_read_unlock(); if (err >= 0) { xfrm_sk_policy_insert(sk, err, pol); @@ -1819,20 +1818,23 @@ out: } EXPORT_SYMBOL(xfrm_user_policy); +static DEFINE_SPINLOCK(xfrm_km_lock); + int xfrm_register_km(struct xfrm_mgr *km) { - write_lock_bh(&xfrm_km_lock); - list_add_tail(&km->list, &xfrm_km_list); - write_unlock_bh(&xfrm_km_lock); + spin_lock_bh(&xfrm_km_lock); + list_add_tail_rcu(&km->list, &xfrm_km_list); + spin_unlock_bh(&xfrm_km_lock); return 0; } EXPORT_SYMBOL(xfrm_register_km); int xfrm_unregister_km(struct xfrm_mgr *km) { - write_lock_bh(&xfrm_km_lock); - list_del(&km->list); - write_unlock_bh(&xfrm_km_lock); + spin_lock_bh(&xfrm_km_lock); + list_del_rcu(&km->list); + spin_unlock_bh(&xfrm_km_lock); + synchronize_rcu(); return 0; } EXPORT_SYMBOL(xfrm_unregister_km); -- 2.39.5