From 77a3ef33e2de6fc8aabd7cb1700bfef81757c28a Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 11 Dec 2008 17:55:59 -0500 Subject: [PATCH] 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 Signed-off-by: J. Bruce Fields --- fs/lockd/mon.c | 62 +++++++++++++++++++++++++++++++++------------------------- 1 file changed, 35 insertions(+), 27 deletions(-) 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 @@ 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; } /** -- 1.8.2.3