From: Trond Myklebust Date: Sun, 24 Jun 2007 15:57:57 -0400 SUNRPC: Give credential cache a local spinlock Signed-off-by: Trond Myklebust --- include/linux/sunrpc/auth.h | 3 +++ net/sunrpc/auth.c | 46 ++++++++++++++++++++++++++++++------------- net/sunrpc/auth_unix.c | 5 +++++ net/sunrpc/sunrpc_syms.c | 1 + 4 files changed, 41 insertions(+), 14 deletions(-) diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index 5974e8a..e5a3b51 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -63,6 +63,7 @@ struct rpc_cred { #define RPC_CREDCACHE_MASK (RPC_CREDCACHE_NR - 1) struct rpc_cred_cache { struct hlist_head hashtable[RPC_CREDCACHE_NR]; + spinlock_t lock; unsigned long nextgc; /* next garbage collection */ unsigned long expire; /* cache expiry interval */ }; @@ -126,6 +127,8 @@ struct rpc_credops { extern const struct rpc_authops authunix_ops; extern const struct rpc_authops authnull_ops; +void __init rpc_init_authunix(void); + int rpcauth_register(const struct rpc_authops *); int rpcauth_unregister(const struct rpc_authops *); struct rpc_auth * rpcauth_create(rpc_authflavor_t, struct rpc_clnt *); diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index ad7bde2..cf1198d 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -120,6 +120,18 @@ rpcauth_unhash_cred_locked(struct rpc_cred *cred) clear_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags); } +static void +rpcauth_unhash_cred(struct rpc_cred *cred) +{ + spinlock_t *cache_lock; + + cache_lock = &cred->cr_auth->au_credcache->lock; + spin_lock(cache_lock); + if (atomic_read(&cred->cr_count) == 0) + rpcauth_unhash_cred_locked(cred); + spin_unlock(cache_lock); +} + /* * Initialize RPC credential cache */ @@ -134,6 +146,7 @@ rpcauth_init_credcache(struct rpc_auth *auth, unsigned long expire) return -ENOMEM; for (i = 0; i < RPC_CREDCACHE_NR; i++) INIT_HLIST_HEAD(&new->hashtable[i]); + spin_lock_init(&new->lock); new->expire = expire; new->nextgc = jiffies + (expire >> 1); auth->au_credcache = new; @@ -168,6 +181,7 @@ rpcauth_clear_credcache(struct rpc_cred_cache *cache) int i; spin_lock(&rpc_credcache_lock); + spin_lock(&cache->lock); for (i = 0; i < RPC_CREDCACHE_NR; i++) { head = &cache->hashtable[i]; while (!hlist_empty(head)) { @@ -177,6 +191,7 @@ rpcauth_clear_credcache(struct rpc_cred_cache *cache) rpcauth_unhash_cred_locked(cred); } } + spin_unlock(&cache->lock); spin_unlock(&rpc_credcache_lock); rpcauth_destroy_credlist(&free); } @@ -202,6 +217,7 @@ rpcauth_destroy_credcache(struct rpc_auth *auth) static void rpcauth_prune_expired(struct list_head *free) { + spinlock_t *cache_lock; struct rpc_cred *cred; while (!list_empty(&cred_unused)) { @@ -212,9 +228,14 @@ rpcauth_prune_expired(struct list_head *free) list_del_init(&cred->cr_lru); if (atomic_read(&cred->cr_count) != 0) continue; - get_rpccred(cred); - list_add_tail(&cred->cr_lru, free); - rpcauth_unhash_cred_locked(cred); + cache_lock = &cred->cr_auth->au_credcache->lock; + spin_lock(cache_lock); + if (atomic_read(&cred->cr_count) == 0) { + get_rpccred(cred); + list_add_tail(&cred->cr_lru, free); + rpcauth_unhash_cred_locked(cred); + } + spin_unlock(cache_lock); } } @@ -253,21 +274,19 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) { if (!entry->cr_ops->crmatch(acred, entry, flags)) continue; - spin_lock(&rpc_credcache_lock); + spin_lock(&cache->lock); if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) { - spin_unlock(&rpc_credcache_lock); + spin_unlock(&cache->lock); continue; } cred = get_rpccred(entry); - spin_unlock(&rpc_credcache_lock); + spin_unlock(&cache->lock); break; } rcu_read_unlock(); - if (cred != NULL) { - rpcauth_gc_credcache(cache, &free); + if (cred != NULL) goto found; - } new = auth->au_ops->crcreate(auth, acred, flags); if (IS_ERR(new)) { @@ -275,7 +294,7 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, goto out; } - spin_lock(&rpc_credcache_lock); + spin_lock(&cache->lock); hlist_for_each_entry(entry, pos, &cache->hashtable[nr], cr_hash) { if (!entry->cr_ops->crmatch(acred, entry, flags)) continue; @@ -288,9 +307,7 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred, hlist_add_head_rcu(&cred->cr_hash, &cache->hashtable[nr]); } else list_add_tail(&new->cr_lru, &free); - rpcauth_prune_expired(&free); - cache->nextgc = jiffies + cache->expire; - spin_unlock(&rpc_credcache_lock); + spin_unlock(&cache->lock); found: if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) && cred->cr_ops->cr_init != NULL @@ -301,6 +318,7 @@ found: cred = ERR_PTR(res); } } + rpcauth_gc_credcache(cache, &free); rpcauth_destroy_credlist(&free); out: return cred; @@ -393,7 +411,7 @@ need_lock: if (!list_empty(&cred->cr_lru)) list_del_init(&cred->cr_lru); if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) - rpcauth_unhash_cred_locked(cred); + rpcauth_unhash_cred(cred); else if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) != 0) { cred->cr_expire = jiffies; list_add_tail(&cred->cr_lru, &cred_unused); diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c index f7ff6ad..205878a 100644 --- a/net/sunrpc/auth_unix.c +++ b/net/sunrpc/auth_unix.c @@ -213,6 +213,11 @@ unx_validate(struct rpc_task *task, __be32 *p) return p; } +void __init rpc_init_authunix(void) +{ + spin_lock_init(&unix_cred_cache.lock); +} + const struct rpc_authops authunix_ops = { .owner = THIS_MODULE, .au_flavor = RPC_AUTH_UNIX, diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c index 3e19e7a..018065f 100644 --- a/net/sunrpc/sunrpc_syms.c +++ b/net/sunrpc/sunrpc_syms.c @@ -152,6 +152,7 @@ init_sunrpc(void) cache_register(&ip_map_cache); cache_register(&unix_gid_cache); init_socket_xprt(); + rpc_init_authunix(); out: return err; }