SUNRPC: Simplify lookup code

We no longer need to worry about whether or not the entry is hashed in order to figure out if the contents are valid. We only care whether or not the refcount is non-zero. Signed-off-by: Trond Myklebust <[email protected]>
mrcsosa · Oct 23, 2018 · 07d02a6 · 07d02a6
1 parent 95cd623
commit 07d02a6
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Showing 2 changed files with 13 additions and 18 deletions.
diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h
@@ -206,11 +206,11 @@ bool			rpcauth_cred_key_to_expire(struct rpc_auth *, struct rpc_cred *);
 char *			rpcauth_stringify_acceptor(struct rpc_cred *);
 
 static inline
-struct rpc_cred *	get_rpccred(struct rpc_cred *cred)
+struct rpc_cred *get_rpccred(struct rpc_cred *cred)
 {
-	if (cred != NULL)
-		atomic_inc(&cred->cr_count);
-	return cred;
+	if (cred != NULL && atomic_inc_not_zero(&cred->cr_count))
+		return cred;
+	return NULL;
 }
 
 /**
@@ -226,9 +226,7 @@ struct rpc_cred *	get_rpccred(struct rpc_cred *cred)
 static inline struct rpc_cred *
 get_rpccred_rcu(struct rpc_cred *cred)
 {
-	if (atomic_inc_not_zero(&cred->cr_count))
-		return cred;
-	return NULL;
+	return get_rpccred(cred);
 }
 
 #endif /* __KERNEL__ */

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
@@ -588,19 +588,15 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
 		if (!entry->cr_ops->crmatch(acred, entry, flags))
 			continue;
 		if (flags & RPCAUTH_LOOKUP_RCU) {
-			if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) &&
-			    !test_bit(RPCAUTH_CRED_NEW, &entry->cr_flags))
-				cred = entry;
+			if (test_bit(RPCAUTH_CRED_NEW, &entry->cr_flags) ||
+			    atomic_read(&entry->cr_count) == 0)
+				continue;
+			cred = entry;
 			break;
 		}
-		spin_lock(&cache->lock);
-		if (test_bit(RPCAUTH_CRED_HASHED, &entry->cr_flags) == 0) {
-			spin_unlock(&cache->lock);
-			continue;
-		}
 		cred = get_rpccred(entry);
-		spin_unlock(&cache->lock);
-		break;
+		if (cred)
+			break;
 	}
 	rcu_read_unlock();
 
@@ -621,7 +617,8 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
 		if (!entry->cr_ops->crmatch(acred, entry, flags))
 			continue;
 		cred = get_rpccred(entry);
-		break;
+		if (cred)
+			break;
 	}
 	if (cred == NULL) {
 		cred = new;