1 files changed, 177 insertions, 43 deletions

diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c
index 8944d1e32ab..4fafea1c9ec 100644
--- a/fs/gfs2/lock_dlm.c
+++ b/fs/gfs2/lock_dlm.c
@@ -7,6 +7,8 @@
  * of the GNU General Public License version 2.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/fs.h>
 #include <linux/dlm.h>
 #include <linux/slab.h>
@@ -18,18 +20,110 @@
 #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)
-		memset(gl->gl_lvb, 0, GDLM_LVB_SIZE);
+	if ((gl->gl_lksb.sb_flags & DLM_SBF_VALNOTVALID) && gl->gl_lksb.sb_lvbptr)
+		memset(gl->gl_lksb.sb_lvbptr, 0, GDLM_LVB_SIZE);
 
 	switch (gl->gl_lksb.sb_status) {
 	case -DLM_EUNLOCK: /* Unlocked, so glock can be freed */
@@ -84,7 +178,7 @@ static void gdlm_bast(void *arg, int mode)
 		gfs2_glock_cb(gl, LM_ST_SHARED);
 		break;
 	default:
-		printk(KERN_ERR "unknown bast mode %d", mode);
+		pr_err("unknown bast mode %d\n", mode);
 		BUG();
 	}
 }
@@ -103,16 +197,19 @@ static int make_mode(const unsigned int lmstate)
 	case LM_ST_SHARED:
 		return DLM_LOCK_PR;
 	}
-	printk(KERN_ERR "unknown LM state %d", lmstate);
+	pr_err("unknown LM state %d\n", lmstate);
 	BUG();
 	return -1;
 }
 
-static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
+static u32 make_flags(struct gfs2_glock *gl, const unsigned int gfs_flags,
 		      const int req)
 {
 	u32 lkf = 0;
 
+	if (gl->gl_lksb.sb_lvbptr)
+		lkf |= DLM_LKF_VALBLK;
+
 	if (gfs_flags & LM_FLAG_TRY)
 		lkf |= DLM_LKF_NOQUEUE;
 
@@ -135,29 +232,50 @@ static u32 make_flags(const u32 lkid, const unsigned int gfs_flags,
 			BUG();
 	}
 
-	if (lkid != 0) 
+	if (gl->gl_lksb.sb_lkid != 0) {
 		lkf |= DLM_LKF_CONVERT;
-
-	lkf |= DLM_LKF_VALBLK;
+		if (test_bit(GLF_BLOCKING, &gl->gl_flags))
+			lkf |= DLM_LKF_QUECVT;
+	}
 
 	return lkf;
 }
 
+static void gfs2_reverse_hex(char *c, u64 value)
+{
+	*c = '0';
+	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);
-
+	lkf = make_flags(gl, 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);
 }
 
@@ -165,6 +283,7 @@ static void gdlm_put_lock(struct gfs2_glock *gl)
 {
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	int lvb_needs_unlock = 0;
 	int error;
 
 	if (gl->gl_lksb.sb_lkid == 0) {
@@ -172,10 +291,26 @@ 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);
+
+	/* don't want to skip dlm_unlock writing the lvb when lock is ex */
+
+	if (gl->gl_lksb.sb_lvbptr && (gl->gl_state == LM_ST_EXCLUSIVE))
+		lvb_needs_unlock = 1;
+
+	if (test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags) &&
+	    !lvb_needs_unlock) {
+		gfs2_glock_free(gl);
+		return;
+	}
+
 	error = dlm_unlock(ls->ls_dlm, gl->gl_lksb.sb_lkid, DLM_LKF_VALBLK,
 			   NULL, gl);
 	if (error) {
-		printk(KERN_ERR "gdlm_unlock %x,%llx err=%d\n",
+		pr_err("gdlm_unlock %x,%llx err=%d\n",
 		       gl->gl_name.ln_type,
 		       (unsigned long long)gl->gl_name.ln_number, error);
 		return;
@@ -333,29 +468,25 @@ static void gdlm_cancel(struct gfs2_glock *gl)
 static void control_lvb_read(struct lm_lockstruct *ls, uint32_t *lvb_gen,
 			     char *lvb_bits)
 {
-	uint32_t gen;
+	__le32 gen;
 	memcpy(lvb_bits, ls->ls_control_lvb, GDLM_LVB_SIZE);
-	memcpy(&gen, lvb_bits, sizeof(uint32_t));
+	memcpy(&gen, lvb_bits, sizeof(__le32));
 	*lvb_gen = le32_to_cpu(gen);
 }
 
 static void control_lvb_write(struct lm_lockstruct *ls, uint32_t lvb_gen,
 			      char *lvb_bits)
 {
-	uint32_t gen;
+	__le32 gen;
 	memcpy(ls->ls_control_lvb, lvb_bits, GDLM_LVB_SIZE);
 	gen = cpu_to_le32(lvb_gen);
-	memcpy(ls->ls_control_lvb, &gen, sizeof(uint32_t));
+	memcpy(ls->ls_control_lvb, &gen, sizeof(__le32));
 }
 
 static int all_jid_bits_clear(char *lvb)
 {
-	int i;
-	for (i = JID_BITMAP_OFFSET; i < GDLM_LVB_SIZE; i++) {
-		if (lvb[i])
-			return 0;
-	}
-	return 1;
+	return !memchr_inv(lvb + JID_BITMAP_OFFSET, 0,
+			GDLM_LVB_SIZE - JID_BITMAP_OFFSET);
 }
 
 static void sync_wait_cb(void *arg)
@@ -447,7 +578,6 @@ static void gfs2_control_func(struct work_struct *work)
 {
 	struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_control_work.work);
 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
-	char lvb_bits[GDLM_LVB_SIZE];
 	uint32_t block_gen, start_gen, lvb_gen, flags;
 	int recover_set = 0;
 	int write_lvb = 0;
@@ -501,7 +631,7 @@ static void gfs2_control_func(struct work_struct *work)
 		return;
 	}
 
-	control_lvb_read(ls, &lvb_gen, lvb_bits);
+	control_lvb_read(ls, &lvb_gen, ls->ls_lvb_bits);
 
 	spin_lock(&ls->ls_recover_spin);
 	if (block_gen != ls->ls_recover_block ||
@@ -531,10 +661,10 @@ static void gfs2_control_func(struct work_struct *work)
 
 			ls->ls_recover_result[i] = 0;
 
-			if (!test_bit_le(i, lvb_bits + JID_BITMAP_OFFSET))
+			if (!test_bit_le(i, ls->ls_lvb_bits + JID_BITMAP_OFFSET))
 				continue;
 
-			__clear_bit_le(i, lvb_bits + JID_BITMAP_OFFSET);
+			__clear_bit_le(i, ls->ls_lvb_bits + JID_BITMAP_OFFSET);
 			write_lvb = 1;
 		}
 	}
@@ -558,7 +688,7 @@ static void gfs2_control_func(struct work_struct *work)
 				continue;
 			if (ls->ls_recover_submit[i] < start_gen) {
 				ls->ls_recover_submit[i] = 0;
-				__set_bit_le(i, lvb_bits + JID_BITMAP_OFFSET);
+				__set_bit_le(i, ls->ls_lvb_bits + JID_BITMAP_OFFSET);
 			}
 		}
 		/* even if there are no bits to set, we need to write the
@@ -572,7 +702,7 @@ static void gfs2_control_func(struct work_struct *work)
 	spin_unlock(&ls->ls_recover_spin);
 
 	if (write_lvb) {
-		control_lvb_write(ls, start_gen, lvb_bits);
+		control_lvb_write(ls, start_gen, ls->ls_lvb_bits);
 		flags = DLM_LKF_CONVERT | DLM_LKF_VALBLK;
 	} else {
 		flags = DLM_LKF_CONVERT;
@@ -592,7 +722,7 @@ static void gfs2_control_func(struct work_struct *work)
 	 */
 
 	for (i = 0; i < recover_size; i++) {
-		if (test_bit_le(i, lvb_bits + JID_BITMAP_OFFSET)) {
+		if (test_bit_le(i, ls->ls_lvb_bits + JID_BITMAP_OFFSET)) {
 			fs_info(sdp, "recover generation %u jid %d\n",
 				start_gen, i);
 			gfs2_recover_set(sdp, i);
@@ -625,7 +755,6 @@ static void gfs2_control_func(struct work_struct *work)
 static int control_mount(struct gfs2_sbd *sdp)
 {
 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
-	char lvb_bits[GDLM_LVB_SIZE];
 	uint32_t start_gen, block_gen, mount_gen, lvb_gen;
 	int mounted_mode;
 	int retries = 0;
@@ -724,7 +853,7 @@ locks_done:
 	 * lvb_gen will be non-zero.
 	 */
 
-	control_lvb_read(ls, &lvb_gen, lvb_bits);
+	control_lvb_read(ls, &lvb_gen, ls->ls_lvb_bits);
 
 	if (lvb_gen == 0xFFFFFFFF) {
 		/* special value to force mount attempts to fail */
@@ -754,7 +883,7 @@ locks_done:
 	 * and all lvb bits to be clear (no pending journal recoveries.)
 	 */
 
-	if (!all_jid_bits_clear(lvb_bits)) {
+	if (!all_jid_bits_clear(ls->ls_lvb_bits)) {
 		/* journals need recovery, wait until all are clear */
 		fs_info(sdp, "control_mount wait for journal recovery\n");
 		goto restart;
@@ -816,7 +945,6 @@ static int dlm_recovery_wait(void *word)
 static int control_first_done(struct gfs2_sbd *sdp)
 {
 	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
-	char lvb_bits[GDLM_LVB_SIZE];
 	uint32_t start_gen, block_gen;
 	int error;
 
@@ -858,8 +986,8 @@ restart:
 	memset(ls->ls_recover_result, 0, ls->ls_recover_size*sizeof(uint32_t));
 	spin_unlock(&ls->ls_recover_spin);
 
-	memset(lvb_bits, 0, sizeof(lvb_bits));
-	control_lvb_write(ls, start_gen, lvb_bits);
+	memset(ls->ls_lvb_bits, 0, GDLM_LVB_SIZE);
+	control_lvb_write(ls, start_gen, ls->ls_lvb_bits);
 
 	error = mounted_lock(sdp, DLM_LOCK_PR, DLM_LKF_CONVERT);
 	if (error)
@@ -889,6 +1017,12 @@ static int set_recover_size(struct gfs2_sbd *sdp, struct dlm_slot *slots,
 	uint32_t old_size, new_size;
 	int i, max_jid;
 
+	if (!ls->ls_lvb_bits) {
+		ls->ls_lvb_bits = kzalloc(GDLM_LVB_SIZE, GFP_NOFS);
+		if (!ls->ls_lvb_bits)
+			return -ENOMEM;
+	}
+
 	max_jid = 0;
 	for (i = 0; i < num_slots; i++) {
 		if (max_jid < slots[i].slot - 1)
@@ -902,8 +1036,8 @@ static int set_recover_size(struct gfs2_sbd *sdp, struct dlm_slot *slots,
 
 	new_size = old_size + RECOVER_SIZE_INC;
 
-	submit = kzalloc(new_size * sizeof(uint32_t), GFP_NOFS);
-	result = kzalloc(new_size * sizeof(uint32_t), GFP_NOFS);
+	submit = kcalloc(new_size, sizeof(uint32_t), GFP_NOFS);
+	result = kcalloc(new_size, sizeof(uint32_t), GFP_NOFS);
 	if (!submit || !result) {
 		kfree(submit);
 		kfree(result);
@@ -924,6 +1058,7 @@ static int set_recover_size(struct gfs2_sbd *sdp, struct dlm_slot *slots,
 
 static void free_recover_size(struct lm_lockstruct *ls)
 {
+	kfree(ls->ls_lvb_bits);
 	kfree(ls->ls_recover_submit);
 	kfree(ls->ls_recover_result);
 	ls->ls_recover_submit = NULL;
@@ -969,7 +1104,7 @@ static void gdlm_recover_slot(void *arg, struct dlm_slot *slot)
 	}
 
 	if (ls->ls_recover_submit[jid]) {
-		fs_info(sdp, "recover_slot jid %d gen %u prev %u",
+		fs_info(sdp, "recover_slot jid %d gen %u prev %u\n",
 			jid, ls->ls_recover_block, ls->ls_recover_submit[jid]);
 	}
 	ls->ls_recover_submit[jid] = ls->ls_recover_block;
@@ -999,7 +1134,7 @@ static void gdlm_recover_done(void *arg, struct dlm_slot *slots, int num_slots,
 		queue_delayed_work(gfs2_control_wq, &sdp->sd_control_work, 0);
 
 	clear_bit(DFL_DLM_RECOVERY, &ls->ls_recover_flags);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 	wake_up_bit(&ls->ls_recover_flags, DFL_DLM_RECOVERY);
 	spin_unlock(&ls->ls_recover_spin);
 }
@@ -1072,6 +1207,7 @@ static int gdlm_mount(struct gfs2_sbd *sdp, const char *table)
 	ls->ls_recover_size = 0;
 	ls->ls_recover_submit = NULL;
 	ls->ls_recover_result = NULL;
+	ls->ls_lvb_bits = NULL;
 
 	error = set_recover_size(sdp, NULL, 0);
 	if (error)
@@ -1092,8 +1228,6 @@ static int gdlm_mount(struct gfs2_sbd *sdp, const char *table)
 	fsname++;
 
 	flags = DLM_LSFL_FS | DLM_LSFL_NEWEXCL;
-	if (ls->ls_nodir)
-		flags |= DLM_LSFL_NODIR;
 
 	/*
 	 * create/join lockspace
@@ -1137,7 +1271,7 @@ static int gdlm_mount(struct gfs2_sbd *sdp, const char *table)
 
 	ls->ls_first = !!test_bit(DFL_FIRST_MOUNT, &ls->ls_recover_flags);
 	clear_bit(SDF_NOJOURNALID, &sdp->sd_flags);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 	wake_up_bit(&sdp->sd_flags, SDF_NOJOURNALID);
 	return 0;
 
@@ -1174,7 +1308,7 @@ static void gdlm_unmount(struct gfs2_sbd *sdp)
 	spin_lock(&ls->ls_recover_spin);
 	set_bit(DFL_UNMOUNT, &ls->ls_recover_flags);
 	spin_unlock(&ls->ls_recover_spin);
-	flush_delayed_work_sync(&sdp->sd_control_work);
+	flush_delayed_work(&sdp->sd_control_work);
 
 	/* mounted_lock and control_lock will be purged in dlm recovery */
 release: