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>
This commit is contained in:
Chuck Lever 2008-12-11 17:55:59 -05:00 committed by J. Bruce Fields
parent b39b897c25
commit 77a3ef33e2

View File

@ -213,6 +213,16 @@ static struct nsm_handle *nsm_lookup_hostname(const char *hostname,
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 @@ struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
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 @@ struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
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;
}
/**