[PATCH] ocfs2: use hlists for lockres hash

Switch from list_head to hlist_head. Make the size of the hash dependent
upon the allocated area, rather than a constant.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 19 insertions, 20 deletions

diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 6ee30837389c..8f3a9e3106fd 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -77,26 +77,26 @@ static void dlm_unregister_domain_handlers(struct dlm_ctxt *dlm);
 
 void __dlm_unhash_lockres(struct dlm_lock_resource *lockres)
 {
-        list_del_init(&lockres->list);
+        hlist_del_init(&lockres->hash_node);
         dlm_lockres_put(lockres);
 }
 
 void __dlm_insert_lockres(struct dlm_ctxt *dlm,
                        struct dlm_lock_resource *res)
 {
-        struct list_head *bucket;
+        struct hlist_head *bucket;
         struct qstr *q;
 
         assert_spin_locked(&dlm->spinlock);
 
         q = &res->lockname;
         q->hash = full_name_hash(q->name, q->len);
-        bucket = &(dlm->resources[q->hash & DLM_HASH_MASK]);
+        bucket = &(dlm->lockres_hash[q->hash % DLM_HASH_BUCKETS]);
 
         /* get a reference for our hashtable */
         dlm_lockres_get(res);
 
-        list_add_tail(&res->list, bucket);
+        hlist_add_head(&res->hash_node, bucket);
 }
 
 struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
@@ -104,9 +104,9 @@ struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
                                          unsigned int len)
 {
         unsigned int hash;
-        struct list_head *iter;
+        struct hlist_node *iter;
         struct dlm_lock_resource *tmpres=NULL;
-        struct list_head *bucket;
+        struct hlist_head *bucket;
 
         mlog_entry("%.*s\n", len, name);
 
@@ -114,11 +114,11 @@ struct dlm_lock_resource * __dlm_lookup_lockres(struct dlm_ctxt *dlm,
 
         hash = full_name_hash(name, len);
 
-        bucket = &(dlm->resources[hash & DLM_HASH_MASK]);
+        bucket = &(dlm->lockres_hash[hash % DLM_HASH_BUCKETS]);
 
         /* check for pre-existing lock */
-        list_for_each(iter, bucket) {
-                tmpres = list_entry(iter, struct dlm_lock_resource, list);
+        hlist_for_each(iter, bucket) {
+                tmpres = hlist_entry(iter, struct dlm_lock_resource, hash_node);
                 if (tmpres->lockname.len == len &&
                     memcmp(tmpres->lockname.name, name, len) == 0) {
                         dlm_lockres_get(tmpres);
@@ -193,8 +193,8 @@ static int dlm_wait_on_domain_helper(const char *domain)
 
 static void dlm_free_ctxt_mem(struct dlm_ctxt *dlm)
 {
-        if (dlm->resources)
-                free_page((unsigned long) dlm->resources);
+        if (dlm->lockres_hash)
+                free_page((unsigned long) dlm->lockres_hash);
 
         if (dlm->name)
                 kfree(dlm->name);
@@ -303,10 +303,10 @@ static void dlm_migrate_all_locks(struct dlm_ctxt *dlm)
         mlog(0, "Migrating locks from domain %s\n", dlm->name);
 restart:
         spin_lock(&dlm->spinlock);
-        for (i=0; i<DLM_HASH_SIZE; i++) {
-                while (!list_empty(&dlm->resources[i])) {
-                        res = list_entry(dlm->resources[i].next,
-                                     struct dlm_lock_resource, list);
+        for (i = 0; i < DLM_HASH_BUCKETS; i++) {
+                while (!hlist_empty(&dlm->lockres_hash[i])) {
+                        res = hlist_entry(dlm->lockres_hash[i].first,
+                                          struct dlm_lock_resource, hash_node);
                         /* need reference when manually grabbing lockres */
                         dlm_lockres_get(res);
                         /* this should unhash the lockres
@@ -1191,18 +1191,17 @@ static struct dlm_ctxt *dlm_alloc_ctxt(const char *domain,
                 goto leave;
         }
 
-        dlm->resources = (struct list_head *) __get_free_page(GFP_KERNEL);
-        if (!dlm->resources) {
+        dlm->lockres_hash = (struct hlist_head *) __get_free_page(GFP_KERNEL);
+        if (!dlm->lockres_hash) {
                 mlog_errno(-ENOMEM);
                 kfree(dlm->name);
                 kfree(dlm);
                 dlm = NULL;
                 goto leave;
         }
-        memset(dlm->resources, 0, PAGE_SIZE);
 
-        for (i=0; i<DLM_HASH_SIZE; i++)
-                INIT_LIST_HEAD(&dlm->resources[i]);
+        for (i=0; i<DLM_HASH_BUCKETS; i++)
+                INIT_HLIST_HEAD(&dlm->lockres_hash[i]);
 
         strcpy(dlm->name, domain);
         dlm->key = key;