NSM: More clean up of nsm_get_handle()
Clean up: refactor nsm_get_handle() so it is organized the same way that
nsm_reboot_lookup() is.
There is an additional micro-optimization here. This change moves the
"hostname & nsm_use_hostnames" test out of the list_for_each_entry()
clause in nsm_get_handle(), since it is loop-invariant.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index 315ca07..99aec74 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -213,6 +213,16 @@
return NULL;
}
+static struct nsm_handle *nsm_lookup_addr(const struct sockaddr *sap)
+{
+ struct nsm_handle *nsm;
+
+ list_for_each_entry(nsm, &nsm_handles, sm_link)
+ if (nlm_cmp_addr(nsm_addr(nsm), sap))
+ return nsm;
+ return NULL;
+}
+
static struct nsm_handle *nsm_lookup_priv(const struct nsm_private *priv)
{
struct nsm_handle *nsm;
@@ -281,8 +291,7 @@
const size_t salen, const char *hostname,
const size_t hostname_len)
{
- struct nsm_handle *nsm = NULL;
- struct nsm_handle *pos;
+ struct nsm_handle *cached, *new = NULL;
if (hostname && memchr(hostname, '/', hostname_len) != NULL) {
if (printk_ratelimit()) {
@@ -295,38 +304,37 @@
retry:
spin_lock(&nsm_lock);
- list_for_each_entry(pos, &nsm_handles, sm_link) {
- if (hostname && nsm_use_hostnames) {
- if (strlen(pos->sm_name) != hostname_len
- || memcmp(pos->sm_name, hostname, hostname_len))
- continue;
- } else if (!nlm_cmp_addr(nsm_addr(pos), sap))
- continue;
- atomic_inc(&pos->sm_count);
- kfree(nsm);
- nsm = pos;
- dprintk("lockd: found nsm_handle for %s (%s), cnt %d\n",
- pos->sm_name, pos->sm_addrbuf,
- atomic_read(&pos->sm_count));
- goto found;
+ if (nsm_use_hostnames && hostname != NULL)
+ cached = nsm_lookup_hostname(hostname, hostname_len);
+ else
+ cached = nsm_lookup_addr(sap);
+
+ if (cached != NULL) {
+ atomic_inc(&cached->sm_count);
+ spin_unlock(&nsm_lock);
+ kfree(new);
+ dprintk("lockd: found nsm_handle for %s (%s), "
+ "cnt %d\n", cached->sm_name,
+ cached->sm_addrbuf,
+ atomic_read(&cached->sm_count));
+ return cached;
}
- if (nsm) {
- list_add(&nsm->sm_link, &nsm_handles);
+
+ if (new != NULL) {
+ list_add(&new->sm_link, &nsm_handles);
+ spin_unlock(&nsm_lock);
dprintk("lockd: created nsm_handle for %s (%s)\n",
- nsm->sm_name, nsm->sm_addrbuf);
- goto found;
+ new->sm_name, new->sm_addrbuf);
+ return new;
}
+
spin_unlock(&nsm_lock);
- nsm = nsm_create_handle(sap, salen, hostname, hostname_len);
- if (unlikely(nsm == NULL))
+ new = nsm_create_handle(sap, salen, hostname, hostname_len);
+ if (unlikely(new == NULL))
return NULL;
goto retry;
-
-found:
- spin_unlock(&nsm_lock);
- return nsm;
}
/**