diff options
-rw-r--r-- | fs/lockd/host.c | 34 |
1 files changed, 19 insertions, 15 deletions
diff --git a/fs/lockd/host.c b/fs/lockd/host.c index de0ffb6106c..c7854791898 100644 --- a/fs/lockd/host.c +++ b/fs/lockd/host.c @@ -457,7 +457,7 @@ nlm_gc_hosts(void) * Manage NSM handles */ static LIST_HEAD(nsm_handles); -static DEFINE_MUTEX(nsm_mutex); +static DEFINE_SPINLOCK(nsm_lock); static struct nsm_handle * __nsm_find(const struct sockaddr_in *sin, @@ -479,7 +479,8 @@ __nsm_find(const struct sockaddr_in *sin, return NULL; } - mutex_lock(&nsm_mutex); +retry: + spin_lock(&nsm_lock); list_for_each_entry(pos, &nsm_handles, sm_link) { if (hostname && nsm_use_hostnames) { @@ -489,28 +490,32 @@ __nsm_find(const struct sockaddr_in *sin, } else if (!nlm_cmp_addr(&pos->sm_addr, sin)) continue; atomic_inc(&pos->sm_count); + kfree(nsm); nsm = pos; - goto out; + goto found; } - - if (!create) { - nsm = NULL; - goto out; + if (nsm) { + list_add(&nsm->sm_link, &nsm_handles); + goto found; } + spin_unlock(&nsm_lock); + + if (!create) + return NULL; nsm = kzalloc(sizeof(*nsm) + hostname_len + 1, GFP_KERNEL); if (nsm == NULL) - goto out; + return NULL; + nsm->sm_addr = *sin; nsm->sm_name = (char *) (nsm + 1); memcpy(nsm->sm_name, hostname, hostname_len); nsm->sm_name[hostname_len] = '\0'; atomic_set(&nsm->sm_count, 1); + goto retry; - list_add(&nsm->sm_link, &nsm_handles); - -out: - mutex_unlock(&nsm_mutex); +found: + spin_unlock(&nsm_lock); return nsm; } @@ -529,10 +534,9 @@ nsm_release(struct nsm_handle *nsm) { if (!nsm) return; - mutex_lock(&nsm_mutex); - if (atomic_dec_and_test(&nsm->sm_count)) { + if (atomic_dec_and_lock(&nsm->sm_count, &nsm_lock)) { list_del(&nsm->sm_link); + spin_unlock(&nsm_lock); kfree(nsm); } - mutex_unlock(&nsm_mutex); } |