dlm: Change rwlock which is only used in write mode to a spinlock

The ls_dirtbl[].lock was an rwlock, but since it was only used in write
mode a spinlock will suffice.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

3 files changed, 11 insertions, 11 deletions

diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c
index 92969f879a17..858fba14aaa6 100644
--- a/fs/dlm/dir.c
+++ b/fs/dlm/dir.c
@@ -156,7 +156,7 @@ void dlm_dir_remove_entry(struct dlm_ls *ls, int nodeid, char *name, int namelen
 
         bucket = dir_hash(ls, name, namelen);
 
-        write_lock(&ls->ls_dirtbl[bucket].lock);
+        spin_lock(&ls->ls_dirtbl[bucket].lock);
 
         de = search_bucket(ls, name, namelen, bucket);
 
@@ -173,7 +173,7 @@ void dlm_dir_remove_entry(struct dlm_ls *ls, int nodeid, char *name, int namelen
         list_del(&de->list);
         kfree(de);
  out:
-        write_unlock(&ls->ls_dirtbl[bucket].lock);
+        spin_unlock(&ls->ls_dirtbl[bucket].lock);
 }
 
 void dlm_dir_clear(struct dlm_ls *ls)
@@ -185,14 +185,14 @@ void dlm_dir_clear(struct dlm_ls *ls)
         DLM_ASSERT(list_empty(&ls->ls_recover_list), );
 
         for (i = 0; i < ls->ls_dirtbl_size; i++) {
-                write_lock(&ls->ls_dirtbl[i].lock);
+                spin_lock(&ls->ls_dirtbl[i].lock);
                 head = &ls->ls_dirtbl[i].list;
                 while (!list_empty(head)) {
                         de = list_entry(head->next, struct dlm_direntry, list);
                         list_del(&de->list);
                         put_free_de(ls, de);
                 }
-                write_unlock(&ls->ls_dirtbl[i].lock);
+                spin_unlock(&ls->ls_dirtbl[i].lock);
         }
 }
 
@@ -307,17 +307,17 @@ static int get_entry(struct dlm_ls *ls, int nodeid, char *name,
 
         bucket = dir_hash(ls, name, namelen);
 
-        write_lock(&ls->ls_dirtbl[bucket].lock);
+        spin_lock(&ls->ls_dirtbl[bucket].lock);
         de = search_bucket(ls, name, namelen, bucket);
         if (de) {
                 *r_nodeid = de->master_nodeid;
-                write_unlock(&ls->ls_dirtbl[bucket].lock);
+                spin_unlock(&ls->ls_dirtbl[bucket].lock);
                 if (*r_nodeid == nodeid)
                         return -EEXIST;
                 return 0;
         }
 
-        write_unlock(&ls->ls_dirtbl[bucket].lock);
+        spin_unlock(&ls->ls_dirtbl[bucket].lock);
 
         if (namelen > DLM_RESNAME_MAXLEN)
                 return -EINVAL;
@@ -330,7 +330,7 @@ static int get_entry(struct dlm_ls *ls, int nodeid, char *name,
         de->length = namelen;
         memcpy(de->name, name, namelen);
 
-        write_lock(&ls->ls_dirtbl[bucket].lock);
+        spin_lock(&ls->ls_dirtbl[bucket].lock);
         tmp = search_bucket(ls, name, namelen, bucket);
         if (tmp) {
                 kfree(de);
@@ -339,7 +339,7 @@ static int get_entry(struct dlm_ls *ls, int nodeid, char *name,
                 list_add_tail(&de->list, &ls->ls_dirtbl[bucket].list);
         }
         *r_nodeid = de->master_nodeid;
-        write_unlock(&ls->ls_dirtbl[bucket].lock);
+        spin_unlock(&ls->ls_dirtbl[bucket].lock);
         return 0;
 }
 
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 076e86f38bc8..d01ca0a711db 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -99,7 +99,7 @@ struct dlm_direntry {
 
 struct dlm_dirtable {
         struct list_head        list;
-        rwlock_t                lock;
+        spinlock_t              lock;
 };
 
 struct dlm_rsbtable {
diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index aa32e5f02493..cd8e2df3c295 100644
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -487,7 +487,7 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
                 goto out_lkbfree;
         for (i = 0; i < size; i++) {
                 INIT_LIST_HEAD(&ls->ls_dirtbl[i].list);
-                rwlock_init(&ls->ls_dirtbl[i].lock);
+                spin_lock_init(&ls->ls_dirtbl[i].lock);
         }
 
         INIT_LIST_HEAD(&ls->ls_waiters);