NetLabel: Consolidate the LSM domain mapping/hashing locks

Currently we use two separate spinlocks to protect both the hash/mapping table
and the default entry.  This could be considered a bit foolish because it adds
complexity without offering any real performance advantage.  This patch
removes the dedicated default spinlock and protects the default entry with the
hash/mapping table spinlock.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Paul Moore 2008-01-29 08:37:57 -05:00 committed by James Morris
parent b64397e0b4
commit 1c3fad936a

View File

@ -54,9 +54,6 @@ struct netlbl_domhsh_tbl {
* hash table should be okay */
static DEFINE_SPINLOCK(netlbl_domhsh_lock);
static struct netlbl_domhsh_tbl *netlbl_domhsh = NULL;
/* Default domain mapping */
static DEFINE_SPINLOCK(netlbl_domhsh_def_lock);
static struct netlbl_dom_map *netlbl_domhsh_def = NULL;
/*
@ -239,24 +236,22 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
INIT_RCU_HEAD(&entry->rcu);
rcu_read_lock();
spin_lock(&netlbl_domhsh_lock);
if (entry->domain != NULL) {
bkt = netlbl_domhsh_hash(entry->domain);
spin_lock(&netlbl_domhsh_lock);
if (netlbl_domhsh_search(entry->domain) == NULL)
list_add_tail_rcu(&entry->list,
&rcu_dereference(netlbl_domhsh)->tbl[bkt]);
else
ret_val = -EEXIST;
spin_unlock(&netlbl_domhsh_lock);
} else {
INIT_LIST_HEAD(&entry->list);
spin_lock(&netlbl_domhsh_def_lock);
if (rcu_dereference(netlbl_domhsh_def) == NULL)
rcu_assign_pointer(netlbl_domhsh_def, entry);
else
ret_val = -EEXIST;
spin_unlock(&netlbl_domhsh_def_lock);
}
spin_unlock(&netlbl_domhsh_lock);
audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info);
if (audit_buf != NULL) {
audit_log_format(audit_buf,
@ -337,23 +332,16 @@ int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info)
entry->domain);
break;
}
if (entry != rcu_dereference(netlbl_domhsh_def)) {
spin_lock(&netlbl_domhsh_lock);
if (entry->valid) {
entry->valid = 0;
spin_lock(&netlbl_domhsh_lock);
if (entry->valid) {
entry->valid = 0;
if (entry != rcu_dereference(netlbl_domhsh_def))
list_del_rcu(&entry->list);
ret_val = 0;
}
spin_unlock(&netlbl_domhsh_lock);
} else {
spin_lock(&netlbl_domhsh_def_lock);
if (entry->valid) {
entry->valid = 0;
else
rcu_assign_pointer(netlbl_domhsh_def, NULL);
ret_val = 0;
}
spin_unlock(&netlbl_domhsh_def_lock);
ret_val = 0;
}
spin_unlock(&netlbl_domhsh_lock);
audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
if (audit_buf != NULL) {