ocfs2/dlm: Track number of mles

The lifetime of a mle is limited to the duration of the lockres mastery
process. While typically this lifetime is fairly short, we have noticed
the number of mles explode under certain circumstances. This patch tracks
the number of each different types of mles and should help us determine
how best to speed up the mastery process.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h
index aa55271..67b3447 100644
--- a/fs/ocfs2/dlm/dlmcommon.h
+++ b/fs/ocfs2/dlm/dlmcommon.h
@@ -52,7 +52,8 @@
 enum dlm_mle_type {
 	DLM_MLE_BLOCK,
 	DLM_MLE_MASTER,
-	DLM_MLE_MIGRATION
+	DLM_MLE_MIGRATION,
+	DLM_MLE_NUM_TYPES
 };
 
 struct dlm_lock_name {
@@ -156,6 +157,8 @@
 	struct list_head mle_hb_events;
 
 	/* these give a really vague idea of the system load */
+	atomic_t mle_tot_count[DLM_MLE_NUM_TYPES];
+	atomic_t mle_cur_count[DLM_MLE_NUM_TYPES];
 	atomic_t local_resources;
 	atomic_t remote_resources;
 	atomic_t unknown_resources;
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 869648c..0479bdf 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -1608,6 +1608,11 @@
 	atomic_set(&dlm->remote_resources, 0);
 	atomic_set(&dlm->unknown_resources, 0);
 
+	for (i = 0; i < DLM_MLE_NUM_TYPES; ++i) {
+		atomic_set(&dlm->mle_tot_count[i], 0);
+		atomic_set(&dlm->mle_cur_count[i], 0);
+	}
+
 	spin_lock_init(&dlm->work_lock);
 	INIT_LIST_HEAD(&dlm->work_list);
 	INIT_WORK(&dlm->dispatched_work, dlm_dispatch_work);
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index 604552e..acfc928 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -325,6 +325,9 @@
 		mle->u.mlename.hash = dlm_lockid_hash(name, namelen);
 	}
 
+	atomic_inc(&dlm->mle_tot_count[mle->type]);
+	atomic_inc(&dlm->mle_cur_count[mle->type]);
+
 	/* copy off the node_map and register hb callbacks on our copy */
 	memcpy(mle->node_map, dlm->domain_map, sizeof(mle->node_map));
 	memcpy(mle->vote_map, dlm->domain_map, sizeof(mle->vote_map));
@@ -467,6 +470,8 @@
 	/* detach the mle from the domain node up/down events */
 	__dlm_mle_detach_hb_events(dlm, mle);
 
+	atomic_dec(&dlm->mle_cur_count[mle->type]);
+
 	/* NOTE: kfree under spinlock here.
 	 * if this is bad, we can move this to a freelist. */
 	kmem_cache_free(dlm_mle_cache, mle);