dlm: use a new list for recovery of master rsb names

Add a new "masters_list" for master rsb structs, with a new
rwlock. The new list is created and used during the recovery
process to send the master rsb names to new nodes. With this
change, the current "root_list" can be used without locking.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 8 insertions, 14 deletions

diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c
index f6acba4310a7..10753486049a 100644
--- a/fs/dlm/dir.c
+++ b/fs/dlm/dir.c
@@ -216,16 +216,13 @@ static struct dlm_rsb *find_rsb_root(struct dlm_ls *ls, const char *name,
 	if (!rv)
 		return r;
 
-	down_read(&ls->ls_root_sem);
-	list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
+	list_for_each_entry(r, &ls->ls_masters_list, res_masters_list) {
 		if (len == r->res_length && !memcmp(name, r->res_name, len)) {
-			up_read(&ls->ls_root_sem);
 			log_debug(ls, "find_rsb_root revert to root_list %s",
 				  r->res_name);
 			return r;
 		}
 	}
-	up_read(&ls->ls_root_sem);
 	return NULL;
 }
 
@@ -241,7 +238,7 @@ void dlm_copy_master_names(struct dlm_ls *ls, const char *inbuf, int inlen,
 	int offset = 0, dir_nodeid;
 	__be16 be_namelen;
 
-	down_read(&ls->ls_root_sem);
+	read_lock(&ls->ls_masters_lock);
 
 	if (inlen > 1) {
 		r = find_rsb_root(ls, inbuf, inlen);
@@ -250,16 +247,13 @@ void dlm_copy_master_names(struct dlm_ls *ls, const char *inbuf, int inlen,
 				  nodeid, inlen, inlen, inbuf);
 			goto out;
 		}
-		list = r->res_root_list.next;
+		list = r->res_masters_list.next;
 	} else {
-		list = ls->ls_root_list.next;
+		list = ls->ls_masters_list.next;
 	}
 
-	for (offset = 0; list != &ls->ls_root_list; list = list->next) {
-		r = list_entry(list, struct dlm_rsb, res_root_list);
-		if (r->res_nodeid)
-			continue;
-
+	for (offset = 0; list != &ls->ls_masters_list; list = list->next) {
+		r = list_entry(list, struct dlm_rsb, res_masters_list);
 		dir_nodeid = dlm_dir_nodeid(r);
 		if (dir_nodeid != nodeid)
 			continue;
@@ -294,7 +288,7 @@ void dlm_copy_master_names(struct dlm_ls *ls, const char *inbuf, int inlen,
 	 * terminating record.
 	 */
 
-	if ((list == &ls->ls_root_list) &&
+	if ((list == &ls->ls_masters_list) &&
 	    (offset + sizeof(uint16_t) <= outlen)) {
 		be_namelen = cpu_to_be16(0xFFFF);
 		memcpy(outbuf + offset, &be_namelen, sizeof(__be16));
@@ -302,6 +296,6 @@ void dlm_copy_master_names(struct dlm_ls *ls, const char *inbuf, int inlen,
 		ls->ls_recover_dir_sent_msg++;
 	}
  out:
-	up_read(&ls->ls_root_sem);
+	read_unlock(&ls->ls_masters_lock);
 }