1 files changed, 528 insertions, 250 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index f07643e21bf..ee4e04fe60f 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -7,6 +7,8 @@
  * of the GNU General Public License version 2.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
@@ -29,6 +31,9 @@
 #include <linux/rcupdate.h>
 #include <linux/rculist_bl.h>
 #include <linux/bit_spinlock.h>
+#include <linux/percpu.h>
+#include <linux/list_sort.h>
+#include <linux/lockref.h>
 
 #include "gfs2.h"
 #include "incore.h"
@@ -45,16 +50,15 @@
 #include "trace_gfs2.h"
 
 struct gfs2_glock_iter {
-	int hash;			/* hash bucket index         */
-	struct gfs2_sbd *sdp;		/* incore superblock         */
-	struct gfs2_glock *gl;		/* current glock struct      */
-	char string[512];		/* scratch space             */
+	int hash;			/* hash bucket index           */
+	unsigned nhash;			/* Index within current bucket */
+	struct gfs2_sbd *sdp;		/* incore superblock           */
+	struct gfs2_glock *gl;		/* current glock struct        */
+	loff_t last_pos;		/* last position               */
 };
 
 typedef void (*glock_examiner) (struct gfs2_glock * gl);
 
-static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl);
-#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { __dump_glock(NULL, gl); BUG(); } } while(0)
 static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
 
 static struct dentry *gfs2_root;
@@ -93,24 +97,24 @@ static unsigned int gl_hash(const struct gfs2_sbd *sdp,
 
 static inline void spin_lock_bucket(unsigned int hash)
 {
-	struct hlist_bl_head *bl = &gl_hash_table[hash];
-	bit_spin_lock(0, (unsigned long *)bl);
+	hlist_bl_lock(&gl_hash_table[hash]);
 }
 
 static inline void spin_unlock_bucket(unsigned int hash)
 {
-	struct hlist_bl_head *bl = &gl_hash_table[hash];
-	__bit_spin_unlock(0, (unsigned long *)bl);
+	hlist_bl_unlock(&gl_hash_table[hash]);
 }
 
 static void gfs2_glock_dealloc(struct rcu_head *rcu)
 {
 	struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu);
 
-	if (gl->gl_ops->go_flags & GLOF_ASPACE)
+	if (gl->gl_ops->go_flags & GLOF_ASPACE) {
 		kmem_cache_free(gfs2_glock_aspace_cachep, gl);
-	else
+	} else {
+		kfree(gl->gl_lksb.sb_lvbptr);
 		kmem_cache_free(gfs2_glock_cachep, gl);
+	}
 }
 
 void gfs2_glock_free(struct gfs2_glock *gl)
@@ -128,10 +132,10 @@ void gfs2_glock_free(struct gfs2_glock *gl)
  *
  */
 
-void gfs2_glock_hold(struct gfs2_glock *gl)
+static void gfs2_glock_hold(struct gfs2_glock *gl)
 {
-	GLOCK_BUG_ON(gl, atomic_read(&gl->gl_ref) == 0);
-	atomic_inc(&gl->gl_ref);
+	GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
+	lockref_get(&gl->gl_lockref);
 }
 
 /**
@@ -145,14 +149,9 @@ static int demote_ok(const struct gfs2_glock *gl)
 {
 	const struct gfs2_glock_operations *glops = gl->gl_ops;
 
-	/* assert_spin_locked(&gl->gl_spin); */
-
 	if (gl->gl_state == LM_ST_UNLOCKED)
 		return 0;
-	if (test_bit(GLF_LFLUSH, &gl->gl_flags))
-		return 0;
-	if ((gl->gl_name.ln_type != LM_TYPE_INODE) &&
-	    !list_empty(&gl->gl_holders))
+	if (!list_empty(&gl->gl_holders))
 		return 0;
 	if (glops->go_demote_ok)
 		return glops->go_demote_ok(gl);
@@ -160,48 +159,34 @@ static int demote_ok(const struct gfs2_glock *gl)
 }
 
 
-/**
- * __gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list
- * @gl: the glock
- *
- * If the glock is demotable, then we add it (or move it) to the end
- * of the glock LRU list.
- */
-
-static void __gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl)
+void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
 {
-	if (demote_ok(gl)) {
-		spin_lock(&lru_lock);
+	spin_lock(&lru_lock);
 
-		if (!list_empty(&gl->gl_lru))
-			list_del_init(&gl->gl_lru);
-		else
-			atomic_inc(&lru_count);
+	if (!list_empty(&gl->gl_lru))
+		list_del_init(&gl->gl_lru);
+	else
+		atomic_inc(&lru_count);
 
-		list_add_tail(&gl->gl_lru, &lru_list);
-		spin_unlock(&lru_lock);
-	}
+	list_add_tail(&gl->gl_lru, &lru_list);
+	set_bit(GLF_LRU, &gl->gl_flags);
+	spin_unlock(&lru_lock);
 }
 
-void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl)
+static void __gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
 {
-	spin_lock(&gl->gl_spin);
-	__gfs2_glock_schedule_for_reclaim(gl);
-	spin_unlock(&gl->gl_spin);
+	if (!list_empty(&gl->gl_lru)) {
+		list_del_init(&gl->gl_lru);
+		atomic_dec(&lru_count);
+		clear_bit(GLF_LRU, &gl->gl_flags);
+	}
 }
 
-/**
- * gfs2_glock_put_nolock() - Decrement reference count on glock
- * @gl: The glock to put
- *
- * This function should only be used if the caller has its own reference
- * to the glock, in addition to the one it is dropping.
- */
-
-void gfs2_glock_put_nolock(struct gfs2_glock *gl)
+static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
 {
-	if (atomic_dec_and_test(&gl->gl_ref))
-		GLOCK_BUG_ON(gl, 1);
+	spin_lock(&lru_lock);
+	__gfs2_glock_remove_from_lru(gl);
+	spin_unlock(&lru_lock);
 }
 
 /**
@@ -215,21 +200,22 @@ void gfs2_glock_put(struct gfs2_glock *gl)
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct address_space *mapping = gfs2_glock2aspace(gl);
 
-	if (atomic_dec_and_test(&gl->gl_ref)) {
-		spin_lock_bucket(gl->gl_hash);
-		hlist_bl_del_rcu(&gl->gl_list);
-		spin_unlock_bucket(gl->gl_hash);
-		spin_lock(&lru_lock);
-		if (!list_empty(&gl->gl_lru)) {
-			list_del_init(&gl->gl_lru);
-			atomic_dec(&lru_count);
-		}
-		spin_unlock(&lru_lock);
-		GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
-		GLOCK_BUG_ON(gl, mapping && mapping->nrpages);
-		trace_gfs2_glock_put(gl);
-		sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
-	}
+	if (lockref_put_or_lock(&gl->gl_lockref))
+		return;
+
+	lockref_mark_dead(&gl->gl_lockref);
+
+	spin_lock(&lru_lock);
+	__gfs2_glock_remove_from_lru(gl);
+	spin_unlock(&lru_lock);
+	spin_unlock(&gl->gl_lockref.lock);
+	spin_lock_bucket(gl->gl_hash);
+	hlist_bl_del_rcu(&gl->gl_list);
+	spin_unlock_bucket(gl->gl_hash);
+	GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
+	GLOCK_BUG_ON(gl, mapping && mapping->nrpages);
+	trace_gfs2_glock_put(gl);
+	sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
 }
 
 /**
@@ -252,7 +238,7 @@ static struct gfs2_glock *search_bucket(unsigned int hash,
 			continue;
 		if (gl->gl_sbd != sdp)
 			continue;
-		if (atomic_inc_not_zero(&gl->gl_ref))
+		if (lockref_get_not_dead(&gl->gl_lockref))
 			return gl;
 	}
 
@@ -291,7 +277,7 @@ static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holde
 static void gfs2_holder_wake(struct gfs2_holder *gh)
 {
 	clear_bit(HIF_WAIT, &gh->gh_iflags);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 	wake_up_bit(&gh->gh_iflags, HIF_WAIT);
 }
 
@@ -404,14 +390,19 @@ static void state_change(struct gfs2_glock *gl, unsigned int new_state)
 	held2 = (new_state != LM_ST_UNLOCKED);
 
 	if (held1 != held2) {
+		GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
 		if (held2)
-			gfs2_glock_hold(gl);
+			gl->gl_lockref.count++;
 		else
-			gfs2_glock_put_nolock(gl);
+			gl->gl_lockref.count--;
 	}
 	if (held1 && held2 && list_empty(&gl->gl_holders))
 		clear_bit(GLF_QUEUED, &gl->gl_flags);
 
+	if (new_state != gl->gl_target)
+		/* shorten our minimum hold time */
+		gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR,
+				       GL_GLOCK_MIN_HOLD);
 	gl->gl_state = new_state;
 	gl->gl_tchange = jiffies;
 }
@@ -420,7 +411,7 @@ static void gfs2_demote_wake(struct gfs2_glock *gl)
 {
 	gl->gl_demote_state = LM_ST_EXCLUSIVE;
 	clear_bit(GLF_DEMOTE, &gl->gl_flags);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 	wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
 }
 
@@ -479,7 +470,7 @@ retry:
 			do_xmote(gl, gh, LM_ST_UNLOCKED);
 			break;
 		default: /* Everything else */
-			printk(KERN_ERR "GFS2: wanted %u got %u\n", gl->gl_target, state);
+			pr_err("wanted %u got %u\n", gl->gl_target, state);
 			GLOCK_BUG_ON(gl, 1);
 		}
 		spin_unlock(&gl->gl_spin);
@@ -536,23 +527,26 @@ __acquires(&gl->gl_spin)
 		do_error(gl, 0); /* Fail queued try locks */
 	}
 	gl->gl_req = target;
+	set_bit(GLF_BLOCKING, &gl->gl_flags);
+	if ((gl->gl_req == LM_ST_UNLOCKED) ||
+	    (gl->gl_state == LM_ST_EXCLUSIVE) ||
+	    (lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB)))
+		clear_bit(GLF_BLOCKING, &gl->gl_flags);
 	spin_unlock(&gl->gl_spin);
-	if (glops->go_xmote_th)
-		glops->go_xmote_th(gl);
+	if (glops->go_sync)
+		glops->go_sync(gl);
 	if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
 		glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
 	clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
 
 	gfs2_glock_hold(gl);
-	if (target != LM_ST_UNLOCKED && (gl->gl_state == LM_ST_SHARED ||
-	    gl->gl_state == LM_ST_DEFERRED) &&
-	    !(lck_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
-		lck_flags |= LM_FLAG_TRY_1CB;
-
 	if (sdp->sd_lockstruct.ls_ops->lm_lock)	{
 		/* lock_dlm */
 		ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
-		GLOCK_BUG_ON(gl, ret);
+		if (ret) {
+			pr_err("lm_lock ret %d\n", ret);
+			GLOCK_BUG_ON(gl, 1);
+		}
 	} else { /* lock_nolock */
 		finish_xmote(gl, target);
 		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
@@ -626,15 +620,15 @@ out:
 
 out_sched:
 	clear_bit(GLF_LOCK, &gl->gl_flags);
-	smp_mb__after_clear_bit();
-	gfs2_glock_hold(gl);
+	smp_mb__after_atomic();
+	gl->gl_lockref.count++;
 	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
-		gfs2_glock_put_nolock(gl);
+		gl->gl_lockref.count--;
 	return;
 
 out_unlock:
 	clear_bit(GLF_LOCK, &gl->gl_flags);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 	return;
 }
 
@@ -650,7 +644,7 @@ static void delete_work_func(struct work_struct *work)
 	/* Note: Unsafe to dereference ip as we don't hold right refs/locks */
 
 	if (ip)
-		inode = gfs2_ilookup(sdp->sd_vfs, no_addr);
+		inode = gfs2_ilookup(sdp->sd_vfs, no_addr, 1);
 	else
 		inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED);
 	if (inode && !IS_ERR(inode)) {
@@ -671,20 +665,30 @@ static void glock_work_func(struct work_struct *work)
 		drop_ref = 1;
 	}
 	spin_lock(&gl->gl_spin);
-	if (test_and_clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
+	if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
 	    gl->gl_state != LM_ST_UNLOCKED &&
 	    gl->gl_demote_state != LM_ST_EXCLUSIVE) {
 		unsigned long holdtime, now = jiffies;
-		holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time;
+
+		holdtime = gl->gl_tchange + gl->gl_hold_time;
 		if (time_before(now, holdtime))
 			delay = holdtime - now;
-		set_bit(delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE, &gl->gl_flags);
+
+		if (!delay) {
+			clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
+			set_bit(GLF_DEMOTE, &gl->gl_flags);
+		}
 	}
 	run_queue(gl, 0);
 	spin_unlock(&gl->gl_spin);
-	if (!delay ||
-	    queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
+	if (!delay)
 		gfs2_glock_put(gl);
+	else {
+		if (gl->gl_name.ln_type != LM_TYPE_INODE)
+			delay = 0;
+		if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
+			gfs2_glock_put(gl);
+	}
 	if (drop_ref)
 		gfs2_glock_put(gl);
 }
@@ -727,25 +731,40 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 		cachep = gfs2_glock_aspace_cachep;
 	else
 		cachep = gfs2_glock_cachep;
-	gl = kmem_cache_alloc(cachep, GFP_KERNEL);
+	gl = kmem_cache_alloc(cachep, GFP_NOFS);
 	if (!gl)
 		return -ENOMEM;
 
+	memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
+
+	if (glops->go_flags & GLOF_LVB) {
+		gl->gl_lksb.sb_lvbptr = kzalloc(GFS2_MIN_LVB_SIZE, GFP_NOFS);
+		if (!gl->gl_lksb.sb_lvbptr) {
+			kmem_cache_free(cachep, gl);
+			return -ENOMEM;
+		}
+	}
+
 	atomic_inc(&sdp->sd_glock_disposal);
+	gl->gl_sbd = sdp;
 	gl->gl_flags = 0;
 	gl->gl_name = name;
-	atomic_set(&gl->gl_ref, 1);
+	gl->gl_lockref.count = 1;
 	gl->gl_state = LM_ST_UNLOCKED;
 	gl->gl_target = LM_ST_UNLOCKED;
 	gl->gl_demote_state = LM_ST_EXCLUSIVE;
 	gl->gl_hash = hash;
 	gl->gl_ops = glops;
-	snprintf(gl->gl_strname, GDLM_STRNAME_BYTES, "%8x%16llx", name.ln_type, (unsigned long long)number);
-	memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
-	gl->gl_lksb.sb_lvbptr = gl->gl_lvb;
+	gl->gl_dstamp = ktime_set(0, 0);
+	preempt_disable();
+	/* We use the global stats to estimate the initial per-glock stats */
+	gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type];
+	preempt_enable();
+	gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0;
+	gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0;
 	gl->gl_tchange = jiffies;
 	gl->gl_object = NULL;
-	gl->gl_sbd = sdp;
+	gl->gl_hold_time = GL_GLOCK_DFT_HOLD;
 	INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
 	INIT_WORK(&gl->gl_delete, delete_work_func);
 
@@ -755,7 +774,7 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 		mapping->host = s->s_bdev->bd_inode;
 		mapping->flags = 0;
 		mapping_set_gfp_mask(mapping, GFP_NOFS);
-		mapping->assoc_mapping = NULL;
+		mapping->private_data = NULL;
 		mapping->backing_dev_info = s->s_bdi;
 		mapping->writeback_index = 0;
 	}
@@ -764,6 +783,7 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 	tmp = search_bucket(hash, sdp, &name);
 	if (tmp) {
 		spin_unlock_bucket(hash);
+		kfree(gl->gl_lksb.sb_lvbptr);
 		kmem_cache_free(cachep, gl);
 		atomic_dec(&sdp->sd_glock_disposal);
 		gl = tmp;
@@ -856,16 +876,25 @@ static int gfs2_glock_demote_wait(void *word)
 	return 0;
 }
 
-static void wait_on_holder(struct gfs2_holder *gh)
-{
-	might_sleep();
-	wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE);
-}
+/**
+ * gfs2_glock_wait - wait on a glock acquisition
+ * @gh: the glock holder
+ *
+ * Returns: 0 on success
+ */
 
-static void wait_on_demote(struct gfs2_glock *gl)
+int gfs2_glock_wait(struct gfs2_holder *gh)
 {
+	unsigned long time1 = jiffies;
+
 	might_sleep();
-	wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE);
+	wait_on_bit(&gh->gh_iflags, HIF_WAIT, gfs2_glock_holder_wait, TASK_UNINTERRUPTIBLE);
+	if (time_after(jiffies, time1 + HZ)) /* have we waited > a second? */
+		/* Lengthen the minimum hold time. */
+		gh->gh_gl->gl_hold_time = min(gh->gh_gl->gl_hold_time +
+					      GL_GLOCK_HOLD_INCR,
+					      GL_GLOCK_MAX_HOLD);
+	return gh->gh_error;
 }
 
 /**
@@ -878,7 +907,7 @@ static void wait_on_demote(struct gfs2_glock *gl)
  */
 
 static void handle_callback(struct gfs2_glock *gl, unsigned int state,
-			    unsigned long delay)
+			    unsigned long delay, bool remote)
 {
 	int bit = delay ? GLF_PENDING_DEMOTE : GLF_DEMOTE;
 
@@ -891,21 +920,8 @@ static void handle_callback(struct gfs2_glock *gl, unsigned int state,
 		gl->gl_demote_state = LM_ST_UNLOCKED;
 	}
 	if (gl->gl_ops->go_callback)
-		gl->gl_ops->go_callback(gl);
-	trace_gfs2_demote_rq(gl);
-}
-
-/**
- * gfs2_glock_wait - wait on a glock acquisition
- * @gh: the glock holder
- *
- * Returns: 0 on success
- */
-
-int gfs2_glock_wait(struct gfs2_holder *gh)
-{
-	wait_on_holder(gh);
-	return gh->gh_error;
+		gl->gl_ops->go_callback(gl, remote);
+	trace_gfs2_demote_rq(gl, remote);
 }
 
 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
@@ -916,14 +932,12 @@ void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
 	va_start(args, fmt);
 
 	if (seq) {
-		struct gfs2_glock_iter *gi = seq->private;
-		vsprintf(gi->string, fmt, args);
-		seq_printf(seq, gi->string);
+		seq_vprintf(seq, fmt, args);
 	} else {
 		vaf.fmt = fmt;
 		vaf.va = &args;
 
-		printk(KERN_ERR " %pV", &vaf);
+		pr_err("%pV", &vaf);
 	}
 
 	va_end(args);
@@ -947,7 +961,7 @@ __acquires(&gl->gl_spin)
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct list_head *insert_pt = NULL;
 	struct gfs2_holder *gh2;
-	int try_lock = 0;
+	int try_futile = 0;
 
 	BUG_ON(gh->gh_owner_pid == NULL);
 	if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
@@ -955,7 +969,7 @@ __acquires(&gl->gl_spin)
 
 	if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
 		if (test_bit(GLF_LOCK, &gl->gl_flags))
-			try_lock = 1;
+			try_futile = !may_grant(gl, gh);
 		if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
 			goto fail;
 	}
@@ -964,9 +978,8 @@ __acquires(&gl->gl_spin)
 		if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
 		    (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK)))
 			goto trap_recursive;
-		if (try_lock &&
-		    !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) &&
-		    !may_grant(gl, gh)) {
+		if (try_futile &&
+		    !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
 fail:
 			gh->gh_error = GLR_TRYFAILED;
 			gfs2_holder_wake(gh);
@@ -979,6 +992,8 @@ fail:
 	}
 	set_bit(GLF_QUEUED, &gl->gl_flags);
 	trace_gfs2_glock_queue(gh, 1);
+	gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT);
+	gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT);
 	if (likely(insert_pt == NULL)) {
 		list_add_tail(&gh->gh_list, &gl->gl_holders);
 		if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY))
@@ -997,15 +1012,15 @@ do_cancel:
 	return;
 
 trap_recursive:
-	print_symbol(KERN_ERR "original: %s\n", gh2->gh_ip);
-	printk(KERN_ERR "pid: %d\n", pid_nr(gh2->gh_owner_pid));
-	printk(KERN_ERR "lock type: %d req lock state : %d\n",
+	pr_err("original: %pSR\n", (void *)gh2->gh_ip);
+	pr_err("pid: %d\n", pid_nr(gh2->gh_owner_pid));
+	pr_err("lock type: %d req lock state : %d\n",
 	       gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
-	print_symbol(KERN_ERR "new: %s\n", gh->gh_ip);
-	printk(KERN_ERR "pid: %d\n", pid_nr(gh->gh_owner_pid));
-	printk(KERN_ERR "lock type: %d req lock state : %d\n",
+	pr_err("new: %pSR\n", (void *)gh->gh_ip);
+	pr_err("pid: %d\n", pid_nr(gh->gh_owner_pid));
+	pr_err("lock type: %d req lock state : %d\n",
 	       gh->gh_gl->gl_name.ln_type, gh->gh_state);
-	__dump_glock(NULL, gl);
+	gfs2_dump_glock(NULL, gl);
 	BUG();
 }
 
@@ -1027,11 +1042,18 @@ int gfs2_glock_nq(struct gfs2_holder *gh)
 	if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
 		return -EIO;
 
+	if (test_bit(GLF_LRU, &gl->gl_flags))
+		gfs2_glock_remove_from_lru(gl);
+
 	spin_lock(&gl->gl_spin);
 	add_to_queue(gh);
-	if ((LM_FLAG_NOEXP & gh->gh_flags) &&
-	    test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
+	if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) &&
+		     test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) {
 		set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
+		gl->gl_lockref.count++;
+		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+			gl->gl_lockref.count--;
+	}
 	run_queue(gl, 1);
 	spin_unlock(&gl->gl_spin);
 
@@ -1068,7 +1090,7 @@ void gfs2_glock_dq(struct gfs2_holder *gh)
 
 	spin_lock(&gl->gl_spin);
 	if (gh->gh_flags & GL_NOCACHE)
-		handle_callback(gl, LM_ST_UNLOCKED, 0);
+		handle_callback(gl, LM_ST_UNLOCKED, 0, false);
 
 	list_del_init(&gh->gh_list);
 	if (find_first_holder(gl) == NULL) {
@@ -1084,7 +1106,9 @@ void gfs2_glock_dq(struct gfs2_holder *gh)
 		    !test_bit(GLF_DEMOTE, &gl->gl_flags))
 			fast_path = 1;
 	}
-	__gfs2_glock_schedule_for_reclaim(gl);
+	if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl))
+		gfs2_glock_add_to_lru(gl);
+
 	trace_gfs2_glock_queue(gh, 0);
 	spin_unlock(&gl->gl_spin);
 	if (likely(fast_path))
@@ -1092,8 +1116,9 @@ void gfs2_glock_dq(struct gfs2_holder *gh)
 
 	gfs2_glock_hold(gl);
 	if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
-	    !test_bit(GLF_DEMOTE, &gl->gl_flags))
-		delay = gl->gl_ops->go_min_hold_time;
+	    !test_bit(GLF_DEMOTE, &gl->gl_flags) &&
+	    gl->gl_name.ln_type == LM_TYPE_INODE)
+		delay = gl->gl_hold_time;
 	if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
 		gfs2_glock_put(gl);
 }
@@ -1102,7 +1127,8 @@ void gfs2_glock_dq_wait(struct gfs2_holder *gh)
 {
 	struct gfs2_glock *gl = gh->gh_gl;
 	gfs2_glock_dq(gh);
-	wait_on_demote(gl);
+	might_sleep();
+	wait_on_bit(&gl->gl_flags, GLF_DEMOTE, gfs2_glock_demote_wait, TASK_UNINTERRUPTIBLE);
 }
 
 /**
@@ -1252,19 +1278,6 @@ void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
 		gfs2_glock_dq(&ghs[num_gh]);
 }
 
-/**
- * gfs2_glock_dq_uninit_m - release multiple glocks
- * @num_gh: the number of structures
- * @ghs: an array of struct gfs2_holder structures
- *
- */
-
-void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs)
-{
-	while (num_gh--)
-		gfs2_glock_dq_uninit(&ghs[num_gh]);
-}
-
 void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
 {
 	unsigned long delay = 0;
@@ -1272,16 +1285,17 @@ void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
 	unsigned long now = jiffies;
 
 	gfs2_glock_hold(gl);
-	holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time;
-	if (test_bit(GLF_QUEUED, &gl->gl_flags)) {
+	holdtime = gl->gl_tchange + gl->gl_hold_time;
+	if (test_bit(GLF_QUEUED, &gl->gl_flags) &&
+	    gl->gl_name.ln_type == LM_TYPE_INODE) {
 		if (time_before(now, holdtime))
 			delay = holdtime - now;
 		if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
-			delay = gl->gl_ops->go_min_hold_time;
+			delay = gl->gl_hold_time;
 	}
 
 	spin_lock(&gl->gl_spin);
-	handle_callback(gl, state, delay);
+	handle_callback(gl, state, delay, true);
 	spin_unlock(&gl->gl_spin);
 	if (queue_delayed_work(glock_workqueue, &gl->gl_work, delay) == 0)
 		gfs2_glock_put(gl);
@@ -1333,7 +1347,7 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
 	spin_lock(&gl->gl_spin);
 	gl->gl_reply = ret;
 
-	if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_flags))) {
+	if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) {
 		if (gfs2_should_freeze(gl)) {
 			set_bit(GLF_FROZEN, &gl->gl_flags);
 			spin_unlock(&gl->gl_spin);
@@ -1341,65 +1355,132 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
 		}
 	}
 
-	spin_unlock(&gl->gl_spin);
+	gl->gl_lockref.count++;
 	set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
-	smp_wmb();
-	gfs2_glock_hold(gl);
+	spin_unlock(&gl->gl_spin);
+
 	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
 		gfs2_glock_put(gl);
 }
 
+static int glock_cmp(void *priv, struct list_head *a, struct list_head *b)
+{
+	struct gfs2_glock *gla, *glb;
+
+	gla = list_entry(a, struct gfs2_glock, gl_lru);
+	glb = list_entry(b, struct gfs2_glock, gl_lru);
+
+	if (gla->gl_name.ln_number > glb->gl_name.ln_number)
+		return 1;
+	if (gla->gl_name.ln_number < glb->gl_name.ln_number)
+		return -1;
+
+	return 0;
+}
+
+/**
+ * gfs2_dispose_glock_lru - Demote a list of glocks
+ * @list: The list to dispose of
+ *
+ * Disposing of glocks may involve disk accesses, so that here we sort
+ * the glocks by number (i.e. disk location of the inodes) so that if
+ * there are any such accesses, they'll be sent in order (mostly).
+ *
+ * Must be called under the lru_lock, but may drop and retake this
+ * lock. While the lru_lock is dropped, entries may vanish from the
+ * list, but no new entries will appear on the list (since it is
+ * private)
+ */
 
-static int gfs2_shrink_glock_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
+static void gfs2_dispose_glock_lru(struct list_head *list)
+__releases(&lru_lock)
+__acquires(&lru_lock)
 {
 	struct gfs2_glock *gl;
-	int may_demote;
-	int nr_skipped = 0;
-	LIST_HEAD(skipped);
 
-	if (nr == 0)
-		goto out;
+	list_sort(NULL, list, glock_cmp);
 
-	if (!(gfp_mask & __GFP_FS))
-		return -1;
+	while(!list_empty(list)) {
+		gl = list_entry(list->next, struct gfs2_glock, gl_lru);
+		list_del_init(&gl->gl_lru);
+		if (!spin_trylock(&gl->gl_spin)) {
+add_back_to_lru:
+			list_add(&gl->gl_lru, &lru_list);
+			atomic_inc(&lru_count);
+			continue;
+		}
+		if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
+			spin_unlock(&gl->gl_spin);
+			goto add_back_to_lru;
+		}
+		clear_bit(GLF_LRU, &gl->gl_flags);
+		gl->gl_lockref.count++;
+		if (demote_ok(gl))
+			handle_callback(gl, LM_ST_UNLOCKED, 0, false);
+		WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
+		if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+			gl->gl_lockref.count--;
+		spin_unlock(&gl->gl_spin);
+		cond_resched_lock(&lru_lock);
+	}
+}
+
+/**
+ * gfs2_scan_glock_lru - Scan the LRU looking for locks to demote
+ * @nr: The number of entries to scan
+ *
+ * This function selects the entries on the LRU which are able to
+ * be demoted, and then kicks off the process by calling
+ * gfs2_dispose_glock_lru() above.
+ */
+
+static long gfs2_scan_glock_lru(int nr)
+{
+	struct gfs2_glock *gl;
+	LIST_HEAD(skipped);
+	LIST_HEAD(dispose);
+	long freed = 0;
 
 	spin_lock(&lru_lock);
-	while(nr && !list_empty(&lru_list)) {
+	while ((nr-- >= 0) && !list_empty(&lru_list)) {
 		gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
-		list_del_init(&gl->gl_lru);
-		atomic_dec(&lru_count);
 
 		/* Test for being demotable */
-		if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
-			gfs2_glock_hold(gl);
-			spin_unlock(&lru_lock);
-			spin_lock(&gl->gl_spin);
-			may_demote = demote_ok(gl);
-			if (may_demote) {
-				handle_callback(gl, LM_ST_UNLOCKED, 0);
-				nr--;
-			}
-			clear_bit(GLF_LOCK, &gl->gl_flags);
-			smp_mb__after_clear_bit();
-			if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
-				gfs2_glock_put_nolock(gl);
-			spin_unlock(&gl->gl_spin);
-			spin_lock(&lru_lock);
+		if (!test_bit(GLF_LOCK, &gl->gl_flags)) {
+			list_move(&gl->gl_lru, &dispose);
+			atomic_dec(&lru_count);
+			freed++;
 			continue;
 		}
-		nr_skipped++;
-		list_add(&gl->gl_lru, &skipped);
+
+		list_move(&gl->gl_lru, &skipped);
 	}
 	list_splice(&skipped, &lru_list);
-	atomic_add(nr_skipped, &lru_count);
+	if (!list_empty(&dispose))
+		gfs2_dispose_glock_lru(&dispose);
 	spin_unlock(&lru_lock);
-out:
-	return (atomic_read(&lru_count) / 100) * sysctl_vfs_cache_pressure;
+
+	return freed;
+}
+
+static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
+					    struct shrink_control *sc)
+{
+	if (!(sc->gfp_mask & __GFP_FS))
+		return SHRINK_STOP;
+	return gfs2_scan_glock_lru(sc->nr_to_scan);
+}
+
+static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
+					     struct shrink_control *sc)
+{
+	return vfs_pressure_ratio(atomic_read(&lru_count));
 }
 
 static struct shrinker glock_shrinker = {
-	.shrink = gfs2_shrink_glock_memory,
 	.seeks = DEFAULT_SEEKS,
+	.count_objects = gfs2_glock_shrink_count,
+	.scan_objects = gfs2_glock_shrink_scan,
 };
 
 /**
@@ -1419,7 +1500,7 @@ static void examine_bucket(glock_examiner examiner, const struct gfs2_sbd *sdp,
 
 	rcu_read_lock();
 	hlist_bl_for_each_entry_rcu(gl, pos, head, gl_list) {
-		if ((gl->gl_sbd == sdp) && atomic_read(&gl->gl_ref))
+		if ((gl->gl_sbd == sdp) && lockref_get_not_dead(&gl->gl_lockref))
 			examiner(gl);
 	}
 	rcu_read_unlock();
@@ -1439,18 +1520,17 @@ static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp)
  * thaw_glock - thaw out a glock which has an unprocessed reply waiting
  * @gl: The glock to thaw
  *
- * N.B. When we freeze a glock, we leave a ref to the glock outstanding,
- * so this has to result in the ref count being dropped by one.
  */
 
 static void thaw_glock(struct gfs2_glock *gl)
 {
 	if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
-		return;
+		goto out;
 	set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
-	gfs2_glock_hold(gl);
-	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
+	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) {
+out:
 		gfs2_glock_put(gl);
+	}
 }
 
 /**
@@ -1461,18 +1541,12 @@ static void thaw_glock(struct gfs2_glock *gl)
 
 static void clear_glock(struct gfs2_glock *gl)
 {
-	spin_lock(&lru_lock);
-	if (!list_empty(&gl->gl_lru)) {
-		list_del_init(&gl->gl_lru);
-		atomic_dec(&lru_count);
-	}
-	spin_unlock(&lru_lock);
+	gfs2_glock_remove_from_lru(gl);
 
 	spin_lock(&gl->gl_spin);
 	if (gl->gl_state != LM_ST_UNLOCKED)
-		handle_callback(gl, LM_ST_UNLOCKED, 0);
+		handle_callback(gl, LM_ST_UNLOCKED, 0, false);
 	spin_unlock(&gl->gl_spin);
-	gfs2_glock_hold(gl);
 	if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0)
 		gfs2_glock_put(gl);
 }
@@ -1488,13 +1562,11 @@ void gfs2_glock_thaw(struct gfs2_sbd *sdp)
 	glock_hash_walk(thaw_glock, sdp);
 }
 
-static int dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
+static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
 {
-	int ret;
 	spin_lock(&gl->gl_spin);
-	ret = __dump_glock(seq, gl);
+	gfs2_dump_glock(seq, gl);
 	spin_unlock(&gl->gl_spin);
-	return ret;
 }
 
 static void dump_glock_func(struct gfs2_glock *gl)
@@ -1512,6 +1584,8 @@ static void dump_glock_func(struct gfs2_glock *gl)
 
 void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
 {
+	set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
+	flush_workqueue(glock_workqueue);
 	glock_hash_walk(clear_glock, sdp);
 	flush_workqueue(glock_workqueue);
 	wait_event(sdp->sd_glock_wait, atomic_read(&sdp->sd_glock_disposal) == 0);
@@ -1581,14 +1655,14 @@ static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags)
  * @seq: the seq_file struct
  * @gh: the glock holder
  *
- * Returns: 0 on success, -ENOBUFS when we run out of space
  */
 
-static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
+static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
 {
 	struct task_struct *gh_owner = NULL;
 	char flags_buf[32];
 
+	rcu_read_lock();
 	if (gh->gh_owner_pid)
 		gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
 	gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n",
@@ -1598,12 +1672,14 @@ static int dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
 		       gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1,
 		       gh_owner ? gh_owner->comm : "(ended)",
 		       (void *)gh->gh_ip);
-	return 0;
+	rcu_read_unlock();
 }
 
-static const char *gflags2str(char *buf, const unsigned long *gflags)
+static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
 {
+	const unsigned long *gflags = &gl->gl_flags;
 	char *p = buf;
+
 	if (test_bit(GLF_LOCK, gflags))
 		*p++ = 'l';
 	if (test_bit(GLF_DEMOTE, gflags))
@@ -1626,12 +1702,18 @@ static const char *gflags2str(char *buf, const unsigned long *gflags)
 		*p++ = 'F';
 	if (test_bit(GLF_QUEUED, gflags))
 		*p++ = 'q';
+	if (test_bit(GLF_LRU, gflags))
+		*p++ = 'L';
+	if (gl->gl_object)
+		*p++ = 'o';
+	if (test_bit(GLF_BLOCKING, gflags))
+		*p++ = 'b';
 	*p = 0;
 	return buf;
 }
 
 /**
- * __dump_glock - print information about a glock
+ * gfs2_dump_glock - print information about a glock
  * @seq: The seq_file struct
  * @gl: the glock
  *
@@ -1645,44 +1727,109 @@ static const char *gflags2str(char *buf, const unsigned long *gflags)
  * example. The field's are n = number (id of the object), f = flags,
  * t = type, s = state, r = refcount, e = error, p = pid.
  *
- * Returns: 0 on success, -ENOBUFS when we run out of space
  */
 
-static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl)
+void gfs2_dump_glock(struct seq_file *seq, const struct gfs2_glock *gl)
 {
 	const struct gfs2_glock_operations *glops = gl->gl_ops;
 	unsigned long long dtime;
 	const struct gfs2_holder *gh;
 	char gflags_buf[32];
-	int error = 0;
 
 	dtime = jiffies - gl->gl_demote_time;
 	dtime *= 1000000/HZ; /* demote time in uSec */
 	if (!test_bit(GLF_DEMOTE, &gl->gl_flags))
 		dtime = 0;
-	gfs2_print_dbg(seq, "G:  s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d r:%d\n",
+	gfs2_print_dbg(seq, "G:  s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d v:%d r:%d m:%ld\n",
 		  state2str(gl->gl_state),
 		  gl->gl_name.ln_type,
 		  (unsigned long long)gl->gl_name.ln_number,
-		  gflags2str(gflags_buf, &gl->gl_flags),
+		  gflags2str(gflags_buf, gl),
 		  state2str(gl->gl_target),
 		  state2str(gl->gl_demote_state), dtime,
 		  atomic_read(&gl->gl_ail_count),
-		  atomic_read(&gl->gl_ref));
+		  atomic_read(&gl->gl_revokes),
+		  (int)gl->gl_lockref.count, gl->gl_hold_time);
+
+	list_for_each_entry(gh, &gl->gl_holders, gh_list)
+		dump_holder(seq, gh);
 
-	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
-		error = dump_holder(seq, gh);
-		if (error)
-			goto out;
-	}
 	if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
-		error = glops->go_dump(seq, gl);
-out:
-	return error;
+		glops->go_dump(seq, gl);
+}
+
+static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr)
+{
+	struct gfs2_glock *gl = iter_ptr;
+
+	seq_printf(seq, "G: n:%u/%llx rtt:%lld/%lld rttb:%lld/%lld irt:%lld/%lld dcnt: %lld qcnt: %lld\n",
+		   gl->gl_name.ln_type,
+		   (unsigned long long)gl->gl_name.ln_number,
+		   (long long)gl->gl_stats.stats[GFS2_LKS_SRTT],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_SRTTB],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_SIRT],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT],
+		   (long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]);
+	return 0;
 }
 
+static const char *gfs2_gltype[] = {
+	"type",
+	"reserved",
+	"nondisk",
+	"inode",
+	"rgrp",
+	"meta",
+	"iopen",
+	"flock",
+	"plock",
+	"quota",
+	"journal",
+};
+
+static const char *gfs2_stype[] = {
+	[GFS2_LKS_SRTT]		= "srtt",
+	[GFS2_LKS_SRTTVAR]	= "srttvar",
+	[GFS2_LKS_SRTTB]	= "srttb",
+	[GFS2_LKS_SRTTVARB]	= "srttvarb",
+	[GFS2_LKS_SIRT]		= "sirt",
+	[GFS2_LKS_SIRTVAR]	= "sirtvar",
+	[GFS2_LKS_DCOUNT]	= "dlm",
+	[GFS2_LKS_QCOUNT]	= "queue",
+};
+
+#define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype))
 
+static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr)
+{
+	struct gfs2_glock_iter *gi = seq->private;
+	struct gfs2_sbd *sdp = gi->sdp;
+	unsigned index = gi->hash >> 3;
+	unsigned subindex = gi->hash & 0x07;
+	s64 value;
+	int i;
+
+	if (index == 0 && subindex != 0)
+		return 0;
 
+	seq_printf(seq, "%-10s %8s:", gfs2_gltype[index],
+		   (index == 0) ? "cpu": gfs2_stype[subindex]);
+
+	for_each_possible_cpu(i) {
+                const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i);
+		if (index == 0) {
+			value = i;
+		} else {
+			value = lkstats->lkstats[index - 1].stats[subindex];
+		}
+		seq_printf(seq, " %15lld", (long long)value);
+	}
+	seq_putc(seq, '\n');
+	return 0;
+}
 
 int __init gfs2_glock_init(void)
 {
@@ -1693,14 +1840,14 @@ int __init gfs2_glock_init(void)
 
 	glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
 					  WQ_HIGHPRI | WQ_FREEZABLE, 0);
-	if (IS_ERR(glock_workqueue))
-		return PTR_ERR(glock_workqueue);
+	if (!glock_workqueue)
+		return -ENOMEM;
 	gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
 						WQ_MEM_RECLAIM | WQ_FREEZABLE,
 						0);
-	if (IS_ERR(gfs2_delete_workqueue)) {
+	if (!gfs2_delete_workqueue) {
 		destroy_workqueue(glock_workqueue);
-		return PTR_ERR(gfs2_delete_workqueue);
+		return -ENOMEM;
 	}
 
 	register_shrinker(&glock_shrinker);
@@ -1735,8 +1882,14 @@ static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi)
 		gl = gi->gl;
 		if (gl) {
 			gi->gl = glock_hash_next(gl);
+			gi->nhash++;
 		} else {
+			if (gi->hash >= GFS2_GL_HASH_SIZE) {
+				rcu_read_unlock();
+				return 1;
+			}
 			gi->gl = glock_hash_chain(gi->hash);
+			gi->nhash = 0;
 		}
 		while (gi->gl == NULL) {
 			gi->hash++;
@@ -1745,9 +1898,11 @@ static int gfs2_glock_iter_next(struct gfs2_glock_iter *gi)
 				return 1;
 			}
 			gi->gl = glock_hash_chain(gi->hash);
+			gi->nhash = 0;
 		}
 	/* Skip entries for other sb and dead entries */
-	} while (gi->sdp != gi->gl->gl_sbd || atomic_read(&gi->gl->gl_ref) == 0);
+	} while (gi->sdp != gi->gl->gl_sbd ||
+		 __lockref_is_dead(&gi->gl->gl_lockref));
 
 	return 0;
 }
@@ -1757,7 +1912,12 @@ static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
 	struct gfs2_glock_iter *gi = seq->private;
 	loff_t n = *pos;
 
-	gi->hash = 0;
+	if (gi->last_pos <= *pos)
+		n = gi->nhash + (*pos - gi->last_pos);
+	else
+		gi->hash = 0;
+
+	gi->nhash = 0;
 	rcu_read_lock();
 
 	do {
@@ -1765,6 +1925,7 @@ static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
 			return NULL;
 	} while (n--);
 
+	gi->last_pos = *pos;
 	return gi->gl;
 }
 
@@ -1774,7 +1935,7 @@ static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
 	struct gfs2_glock_iter *gi = seq->private;
 
 	(*pos)++;
-
+	gi->last_pos = *pos;
 	if (gfs2_glock_iter_next(gi))
 		return NULL;
 
@@ -1792,7 +1953,37 @@ static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
 
 static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
 {
-	return dump_glock(seq, iter_ptr);
+	dump_glock(seq, iter_ptr);
+	return 0;
+}
+
+static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	struct gfs2_glock_iter *gi = seq->private;
+
+	gi->hash = *pos;
+	if (*pos >= GFS2_NR_SBSTATS)
+		return NULL;
+	preempt_disable();
+	return SEQ_START_TOKEN;
+}
+
+static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr,
+				   loff_t *pos)
+{
+	struct gfs2_glock_iter *gi = seq->private;
+	(*pos)++;
+	gi->hash++;
+	if (gi->hash >= GFS2_NR_SBSTATS) {
+		preempt_enable();
+		return NULL;
+	}
+	return SEQ_START_TOKEN;
+}
+
+static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr)
+{
+	preempt_enable();
 }
 
 static const struct seq_operations gfs2_glock_seq_ops = {
@@ -1802,7 +1993,23 @@ static const struct seq_operations gfs2_glock_seq_ops = {
 	.show  = gfs2_glock_seq_show,
 };
 
-static int gfs2_debugfs_open(struct inode *inode, struct file *file)
+static const struct seq_operations gfs2_glstats_seq_ops = {
+	.start = gfs2_glock_seq_start,
+	.next  = gfs2_glock_seq_next,
+	.stop  = gfs2_glock_seq_stop,
+	.show  = gfs2_glstats_seq_show,
+};
+
+static const struct seq_operations gfs2_sbstats_seq_ops = {
+	.start = gfs2_sbstats_seq_start,
+	.next  = gfs2_sbstats_seq_next,
+	.stop  = gfs2_sbstats_seq_stop,
+	.show  = gfs2_sbstats_seq_show,
+};
+
+#define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL)
+
+static int gfs2_glocks_open(struct inode *inode, struct file *file)
 {
 	int ret = seq_open_private(file, &gfs2_glock_seq_ops,
 				   sizeof(struct gfs2_glock_iter));
@@ -1810,13 +2017,59 @@ static int gfs2_debugfs_open(struct inode *inode, struct file *file)
 		struct seq_file *seq = file->private_data;
 		struct gfs2_glock_iter *gi = seq->private;
 		gi->sdp = inode->i_private;
+		seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
+		if (seq->buf)
+			seq->size = GFS2_SEQ_GOODSIZE;
+	}
+	return ret;
+}
+
+static int gfs2_glstats_open(struct inode *inode, struct file *file)
+{
+	int ret = seq_open_private(file, &gfs2_glstats_seq_ops,
+				   sizeof(struct gfs2_glock_iter));
+	if (ret == 0) {
+		struct seq_file *seq = file->private_data;
+		struct gfs2_glock_iter *gi = seq->private;
+		gi->sdp = inode->i_private;
+		seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
+		if (seq->buf)
+			seq->size = GFS2_SEQ_GOODSIZE;
+	}
+	return ret;
+}
+
+static int gfs2_sbstats_open(struct inode *inode, struct file *file)
+{
+	int ret = seq_open_private(file, &gfs2_sbstats_seq_ops,
+				   sizeof(struct gfs2_glock_iter));
+	if (ret == 0) {
+		struct seq_file *seq = file->private_data;
+		struct gfs2_glock_iter *gi = seq->private;
+		gi->sdp = inode->i_private;
 	}
 	return ret;
 }
 
-static const struct file_operations gfs2_debug_fops = {
+static const struct file_operations gfs2_glocks_fops = {
 	.owner   = THIS_MODULE,
-	.open    = gfs2_debugfs_open,
+	.open    = gfs2_glocks_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release_private,
+};
+
+static const struct file_operations gfs2_glstats_fops = {
+	.owner   = THIS_MODULE,
+	.open    = gfs2_glstats_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release_private,
+};
+
+static const struct file_operations gfs2_sbstats_fops = {
+	.owner   = THIS_MODULE,
+	.open	 = gfs2_sbstats_open,
 	.read    = seq_read,
 	.llseek  = seq_lseek,
 	.release = seq_release_private,
@@ -1830,20 +2083,45 @@ int gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
 	sdp->debugfs_dentry_glocks = debugfs_create_file("glocks",
 							 S_IFREG | S_IRUGO,
 							 sdp->debugfs_dir, sdp,
-							 &gfs2_debug_fops);
+							 &gfs2_glocks_fops);
 	if (!sdp->debugfs_dentry_glocks)
-		return -ENOMEM;
+		goto fail;
+
+	sdp->debugfs_dentry_glstats = debugfs_create_file("glstats",
+							S_IFREG | S_IRUGO,
+							sdp->debugfs_dir, sdp,
+							&gfs2_glstats_fops);
+	if (!sdp->debugfs_dentry_glstats)
+		goto fail;
+
+	sdp->debugfs_dentry_sbstats = debugfs_create_file("sbstats",
+							S_IFREG | S_IRUGO,
+							sdp->debugfs_dir, sdp,
+							&gfs2_sbstats_fops);
+	if (!sdp->debugfs_dentry_sbstats)
+		goto fail;
 
 	return 0;
+fail:
+	gfs2_delete_debugfs_file(sdp);
+	return -ENOMEM;
 }
 
 void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
 {
-	if (sdp && sdp->debugfs_dir) {
+	if (sdp->debugfs_dir) {
 		if (sdp->debugfs_dentry_glocks) {
 			debugfs_remove(sdp->debugfs_dentry_glocks);
 			sdp->debugfs_dentry_glocks = NULL;
 		}
+		if (sdp->debugfs_dentry_glstats) {
+			debugfs_remove(sdp->debugfs_dentry_glstats);
+			sdp->debugfs_dentry_glstats = NULL;
+		}
+		if (sdp->debugfs_dentry_sbstats) {
+			debugfs_remove(sdp->debugfs_dentry_sbstats);
+			sdp->debugfs_dentry_sbstats = NULL;
+		}
 		debugfs_remove(sdp->debugfs_dir);
 		sdp->debugfs_dir = NULL;
 	}