5 files changed, 431 insertions, 19 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 351a3e797789..dab2526071cc 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -29,6 +29,7 @@
 #include <linux/rcupdate.h>
 #include <linux/rculist_bl.h>
 #include <linux/bit_spinlock.h>
+#include <linux/percpu.h>
 
 #include "gfs2.h"
 #include "incore.h"
@@ -543,6 +544,11 @@ __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);
@@ -744,6 +750,7 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 		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);
@@ -752,12 +759,17 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 	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);
+	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;
 	memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
 	gl->gl_lksb.sb_lvbptr = gl->gl_lvb;
 	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);
@@ -999,6 +1011,8 @@ 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))
@@ -1658,6 +1672,8 @@ static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
 		*p++ = 'L';
 	if (gl->gl_object)
 		*p++ = 'o';
+	if (test_bit(GLF_BLOCKING, gflags))
+		*p++ = 'b';
 	*p = 0;
 	return buf;
 }
@@ -1714,8 +1730,78 @@ out:
 	return error;
 }
 
+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)
 {
@@ -1828,6 +1914,35 @@ static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
 	return dump_glock(seq, iter_ptr);
 }
 
+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 = {
 	.start = gfs2_glock_seq_start,
 	.next  = gfs2_glock_seq_next,
@@ -1835,7 +1950,21 @@ 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,
+};
+
+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));
@@ -1847,9 +1976,49 @@ static int gfs2_debugfs_open(struct inode *inode, struct file *file)
 	return ret;
 }
 
-static const struct file_operations gfs2_debug_fops = {
+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;
+	}
+	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_glocks_fops = {
+	.owner   = THIS_MODULE,
+	.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_debugfs_open,
+	.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,
@@ -1863,20 +2032,45 @@ 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;
 	}
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 97742a7ea9cc..4d546df58ac9 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -19,6 +19,8 @@
 #include <linux/rculist_bl.h>
 #include <linux/completion.h>
 #include <linux/rbtree.h>
+#include <linux/ktime.h>
+#include <linux/percpu.h>
 
 #define DIO_WAIT	0x00000010
 #define DIO_METADATA	0x00000020
@@ -205,6 +207,22 @@ struct gfs2_glock_operations {
 };
 
 enum {
+	GFS2_LKS_SRTT = 0,	/* Non blocking smoothed round trip time */
+	GFS2_LKS_SRTTVAR = 1,	/* Non blocking smoothed variance */
+	GFS2_LKS_SRTTB = 2,	/* Blocking smoothed round trip time */
+	GFS2_LKS_SRTTVARB = 3,	/* Blocking smoothed variance */
+	GFS2_LKS_SIRT = 4,	/* Smoothed Inter-request time */
+	GFS2_LKS_SIRTVAR = 5,	/* Smoothed Inter-request variance */
+	GFS2_LKS_DCOUNT = 6,	/* Count of dlm requests */
+	GFS2_LKS_QCOUNT = 7,	/* Count of gfs2_holder queues */
+	GFS2_NR_LKSTATS
+};
+
+struct gfs2_lkstats {
+	s64 stats[GFS2_NR_LKSTATS];
+};
+
+enum {
 	/* States */
 	HIF_HOLDER		= 6,  /* Set for gh that "holds" the glock */
 	HIF_FIRST		= 7,
@@ -238,10 +256,12 @@ enum {
 	GLF_QUEUED			= 12,
 	GLF_LRU				= 13,
 	GLF_OBJECT			= 14, /* Used only for tracing */
+	GLF_BLOCKING			= 15,
 };
 
 struct gfs2_glock {
 	struct hlist_bl_node gl_list;
+	struct gfs2_sbd *gl_sbd;
 	unsigned long gl_flags;		/* GLF_... */
 	struct lm_lockname gl_name;
 	atomic_t gl_ref;
@@ -261,16 +281,14 @@ struct gfs2_glock {
 	struct list_head gl_holders;
 
 	const struct gfs2_glock_operations *gl_ops;
-	char gl_strname[GDLM_STRNAME_BYTES];
+	ktime_t gl_dstamp;
+	struct gfs2_lkstats gl_stats;
 	struct dlm_lksb gl_lksb;
 	char gl_lvb[32];
 	unsigned long gl_tchange;
 	void *gl_object;
 
 	struct list_head gl_lru;
-
-	struct gfs2_sbd *gl_sbd;
-
 	struct list_head gl_ail_list;
 	atomic_t gl_ail_count;
 	atomic_t gl_revokes;
@@ -560,8 +578,14 @@ struct lm_lockstruct {
 	uint32_t *ls_recover_result; /* result of last jid recovery */
 };
 
+struct gfs2_pcpu_lkstats {
+	/* One struct for each glock type */
+	struct gfs2_lkstats lkstats[10];
+};
+
 struct gfs2_sbd {
 	struct super_block *sd_vfs;
+	struct gfs2_pcpu_lkstats __percpu *sd_lkstats;
 	struct kobject sd_kobj;
 	unsigned long sd_flags;	/* SDF_... */
 	struct gfs2_sb_host sd_sb;
@@ -725,8 +749,23 @@ struct gfs2_sbd {
 
 	unsigned long sd_last_warning;
 	struct dentry *debugfs_dir;    /* debugfs directory */
-	struct dentry *debugfs_dentry_glocks; /* for debugfs */
+	struct dentry *debugfs_dentry_glocks;
+	struct dentry *debugfs_dentry_glstats;
+	struct dentry *debugfs_dentry_sbstats;
 };
 
+static inline void gfs2_glstats_inc(struct gfs2_glock *gl, int which)
+{
+	gl->gl_stats.stats[which]++;
+}
+
+static inline void gfs2_sbstats_inc(const struct gfs2_glock *gl, int which)
+{
+	const struct gfs2_sbd *sdp = gl->gl_sbd;
+	preempt_disable();
+	this_cpu_ptr(sdp->sd_lkstats)->lkstats[gl->gl_name.ln_type].stats[which]++;
+	preempt_enable();
+}
+
 #endif /* __INCORE_DOT_H__ */
 
diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c
index 8944d1e32ab5..f8411bd1b805 100644
--- a/fs/gfs2/lock_dlm.c
+++ b/fs/gfs2/lock_dlm.c
@@ -18,14 +18,106 @@
 #include "glock.h"
 #include "util.h"
 #include "sys.h"
+#include "trace_gfs2.h"
 
 extern struct workqueue_struct *gfs2_control_wq;
 
+/**
+ * gfs2_update_stats - Update time based stats
+ * @mv: Pointer to mean/variance structure to update
+ * @sample: New data to include
+ *
+ * @delta is the difference between the current rtt sample and the
+ * running average srtt. We add 1/8 of that to the srtt in order to
+ * update the current srtt estimate. The varience estimate is a bit
+ * more complicated. We subtract the abs value of the @delta from
+ * the current variance estimate and add 1/4 of that to the running
+ * total.
+ *
+ * Note that the index points at the array entry containing the smoothed
+ * mean value, and the variance is always in the following entry
+ *
+ * Reference: TCP/IP Illustrated, vol 2, p. 831,832
+ * All times are in units of integer nanoseconds. Unlike the TCP/IP case,
+ * they are not scaled fixed point.
+ */
+
+static inline void gfs2_update_stats(struct gfs2_lkstats *s, unsigned index,
+				     s64 sample)
+{
+	s64 delta = sample - s->stats[index];
+	s->stats[index] += (delta >> 3);
+	index++;
+	s->stats[index] += ((abs64(delta) - s->stats[index]) >> 2);
+}
+
+/**
+ * gfs2_update_reply_times - Update locking statistics
+ * @gl: The glock to update
+ *
+ * This assumes that gl->gl_dstamp has been set earlier.
+ *
+ * The rtt (lock round trip time) is an estimate of the time
+ * taken to perform a dlm lock request. We update it on each
+ * reply from the dlm.
+ *
+ * The blocking flag is set on the glock for all dlm requests
+ * which may potentially block due to lock requests from other nodes.
+ * DLM requests where the current lock state is exclusive, the
+ * requested state is null (or unlocked) or where the TRY or
+ * TRY_1CB flags are set are classified as non-blocking. All
+ * other DLM requests are counted as (potentially) blocking.
+ */
+static inline void gfs2_update_reply_times(struct gfs2_glock *gl)
+{
+	struct gfs2_pcpu_lkstats *lks;
+	const unsigned gltype = gl->gl_name.ln_type;
+	unsigned index = test_bit(GLF_BLOCKING, &gl->gl_flags) ?
+			 GFS2_LKS_SRTTB : GFS2_LKS_SRTT;
+	s64 rtt;
+
+	preempt_disable();
+	rtt = ktime_to_ns(ktime_sub(ktime_get_real(), gl->gl_dstamp));
+	lks = this_cpu_ptr(gl->gl_sbd->sd_lkstats);
+	gfs2_update_stats(&gl->gl_stats, index, rtt);		/* Local */
+	gfs2_update_stats(&lks->lkstats[gltype], index, rtt);	/* Global */
+	preempt_enable();
+
+	trace_gfs2_glock_lock_time(gl, rtt);
+}
+
+/**
+ * gfs2_update_request_times - Update locking statistics
+ * @gl: The glock to update
+ *
+ * The irt (lock inter-request times) measures the average time
+ * between requests to the dlm. It is updated immediately before
+ * each dlm call.
+ */
+
+static inline void gfs2_update_request_times(struct gfs2_glock *gl)
+{
+	struct gfs2_pcpu_lkstats *lks;
+	const unsigned gltype = gl->gl_name.ln_type;
+	ktime_t dstamp;
+	s64 irt;
+
+	preempt_disable();
+	dstamp = gl->gl_dstamp;
+	gl->gl_dstamp = ktime_get_real();
+	irt = ktime_to_ns(ktime_sub(gl->gl_dstamp, dstamp));
+	lks = this_cpu_ptr(gl->gl_sbd->sd_lkstats);
+	gfs2_update_stats(&gl->gl_stats, GFS2_LKS_SIRT, irt);		/* Local */
+	gfs2_update_stats(&lks->lkstats[gltype], GFS2_LKS_SIRT, irt);	/* Global */
+	preempt_enable();
+}
+ 
 static void gdlm_ast(void *arg)
 {
 	struct gfs2_glock *gl = arg;
 	unsigned ret = gl->gl_state;
 
+	gfs2_update_reply_times(gl);
 	BUG_ON(gl->gl_lksb.sb_flags & DLM_SBF_DEMOTED);
 
 	if (gl->gl_lksb.sb_flags & DLM_SBF_VALNOTVALID)
@@ -111,7 +203,7 @@ static int make_mode(const unsigned int lmstate)
 static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
 		      const int req)
 {
-	u32 lkf = 0;
+	u32 lkf = DLM_LKF_VALBLK;
 
 	if (gfs_flags & LM_FLAG_TRY)
 		lkf |= DLM_LKF_NOQUEUE;
@@ -138,26 +230,43 @@ static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
 	if (lkid != 0) 
 		lkf |= DLM_LKF_CONVERT;
 
-	lkf |= DLM_LKF_VALBLK;
-
 	return lkf;
 }
 
+static void gfs2_reverse_hex(char *c, u64 value)
+{
+	while (value) {
+		*c-- = hex_asc[value & 0x0f];
+		value >>= 4;
+	}
+}
+
 static int gdlm_lock(struct gfs2_glock *gl, unsigned int req_state,
 		     unsigned int flags)
 {
 	struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct;
 	int req;
 	u32 lkf;
+	char strname[GDLM_STRNAME_BYTES] = "";
 
 	req = make_mode(req_state);
 	lkf = make_flags(gl->gl_lksb.sb_lkid, flags, req);
-
+	gfs2_glstats_inc(gl, GFS2_LKS_DCOUNT);
+	gfs2_sbstats_inc(gl, GFS2_LKS_DCOUNT);
+	if (gl->gl_lksb.sb_lkid) {
+		gfs2_update_request_times(gl);
+	} else {
+		memset(strname, ' ', GDLM_STRNAME_BYTES - 1);
+		strname[GDLM_STRNAME_BYTES - 1] = '\0';
+		gfs2_reverse_hex(strname + 7, gl->gl_name.ln_type);
+		gfs2_reverse_hex(strname + 23, gl->gl_name.ln_number);
+		gl->gl_dstamp = ktime_get_real();
+	}
 	/*
 	 * Submit the actual lock request.
 	 */
 
-	return dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, gl->gl_strname,
+	return dlm_lock(ls->ls_dlm, req, &gl->gl_lksb, lkf, strname,
 			GDLM_STRNAME_BYTES - 1, 0, gdlm_ast, gl, gdlm_bast);
 }
 
@@ -172,6 +281,10 @@ static void gdlm_put_lock(struct gfs2_glock *gl)
 		return;
 	}
 
+	clear_bit(GLF_BLOCKING, &gl->gl_flags);
+	gfs2_glstats_inc(gl, GFS2_LKS_DCOUNT);
+	gfs2_sbstats_inc(gl, GFS2_LKS_DCOUNT);
+	gfs2_update_request_times(gl);
 	error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK,
 			   NULL, gl);
 	if (error) {
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 24f609c9ef91..a55baa7f3239 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -68,6 +68,12 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb)
 
 	sb->s_fs_info = sdp;
 	sdp->sd_vfs = sb;
+	sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
+	if (!sdp->sd_lkstats) {
+		kfree(sdp);
+		return NULL;
+	}
+
 	set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
 	gfs2_tune_init(&sdp->sd_tune);
 
@@ -1221,6 +1227,7 @@ fail_sys:
 	gfs2_sys_fs_del(sdp);
 fail:
 	gfs2_delete_debugfs_file(sdp);
+	free_percpu(sdp->sd_lkstats);
 	kfree(sdp);
 	sb->s_fs_info = NULL;
 	return error;
@@ -1393,6 +1400,7 @@ static void gfs2_kill_sb(struct super_block *sb)
 	shrink_dcache_sb(sb);
 	kill_block_super(sb);
 	gfs2_delete_debugfs_file(sdp);
+	free_percpu(sdp->sd_lkstats);
 	kfree(sdp);
 }
 
diff --git a/fs/gfs2/trace_gfs2.h b/fs/gfs2/trace_gfs2.h
index 5d07609ec57d..dfa89cd75534 100644
--- a/fs/gfs2/trace_gfs2.h
+++ b/fs/gfs2/trace_gfs2.h
@@ -11,6 +11,7 @@
 #include <linux/dlmconstants.h>
 #include <linux/gfs2_ondisk.h>
 #include <linux/writeback.h>
+#include <linux/ktime.h>
 #include "incore.h"
 #include "glock.h"
 
@@ -43,7 +44,8 @@
 	{(1UL << GLF_FROZEN),			"F" },		\
 	{(1UL << GLF_QUEUED),			"q" },		\
 	{(1UL << GLF_LRU),			"L" },		\
-	{(1UL << GLF_OBJECT),			"o" })
+	{(1UL << GLF_OBJECT),			"o" },		\
+	{(1UL << GLF_BLOCKING),			"b" })
 
 #ifndef NUMPTY
 #define NUMPTY
@@ -236,6 +238,62 @@ TRACE_EVENT(gfs2_glock_queue,
 		  glock_trace_name(__entry->state))
 );
 
+/* DLM sends a reply to GFS2 */
+TRACE_EVENT(gfs2_glock_lock_time,
+
+	TP_PROTO(const struct gfs2_glock *gl, s64 tdiff),
+
+	TP_ARGS(gl, tdiff),
+
+	TP_STRUCT__entry(
+		__field(	dev_t,	dev		)
+		__field(	u64,	glnum		)
+		__field(	u32,	gltype		)
+		__field(	int,	status		)
+		__field(	char,	flags		)
+		__field(	s64,	tdiff		)
+		__field(	s64,	srtt		)
+		__field(	s64,	srttvar		)
+		__field(	s64,	srttb		)
+		__field(	s64,	srttvarb	)
+		__field(	s64,	sirt		)
+		__field(	s64,	sirtvar		)
+		__field(	s64,	dcount		)
+		__field(	s64,	qcount		)
+	),
+
+	TP_fast_assign(
+		__entry->dev            = gl->gl_sbd->sd_vfs->s_dev;
+		__entry->glnum          = gl->gl_name.ln_number;
+		__entry->gltype         = gl->gl_name.ln_type;
+		__entry->status		= gl->gl_lksb.sb_status;
+		__entry->flags		= gl->gl_lksb.sb_flags;
+		__entry->tdiff		= tdiff;
+		__entry->srtt		= gl->gl_stats.stats[GFS2_LKS_SRTT];
+		__entry->srttvar	= gl->gl_stats.stats[GFS2_LKS_SRTTVAR];
+		__entry->srttb		= gl->gl_stats.stats[GFS2_LKS_SRTTB];
+		__entry->srttvarb	= gl->gl_stats.stats[GFS2_LKS_SRTTVARB];
+		__entry->sirt		= gl->gl_stats.stats[GFS2_LKS_SIRT];
+		__entry->sirtvar	= gl->gl_stats.stats[GFS2_LKS_SIRTVAR];
+		__entry->dcount		= gl->gl_stats.stats[GFS2_LKS_DCOUNT];
+		__entry->qcount		= gl->gl_stats.stats[GFS2_LKS_QCOUNT];
+	),
+
+	TP_printk("%u,%u glock %d:%lld status:%d flags:%02x tdiff:%lld srtt:%lld/%lld srttb:%lld/%lld sirt:%lld/%lld dcnt:%lld qcnt:%lld",
+		  MAJOR(__entry->dev), MINOR(__entry->dev), __entry->gltype,
+		  (unsigned long long)__entry->glnum,
+		  __entry->status, __entry->flags,
+		  (long long)__entry->tdiff,
+		  (long long)__entry->srtt,
+		  (long long)__entry->srttvar,
+		  (long long)__entry->srttb,
+		  (long long)__entry->srttvarb,
+		  (long long)__entry->sirt,
+		  (long long)__entry->sirtvar,
+		  (long long)__entry->dcount,
+		  (long long)__entry->qcount)
+);
+
 /* Section 2 - Log/journal
  *
  * Objectives: