4 files changed, 404 insertions, 2 deletions

diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 7e958c8..1b7f282 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -232,7 +232,8 @@ __flush_batch(journal_t *journal, struct buffer_head **bhs, int *batch_count)
  * Called under jbd_lock_bh_state(jh2bh(jh)), and drops it
  */
 static int __process_buffer(journal_t *journal, struct journal_head *jh,
-			struct buffer_head **bhs, int *batch_count)
+			struct buffer_head **bhs, int *batch_count,
+			transaction_t *transaction)
 {
 	struct buffer_head *bh = jh2bh(jh);
 	int ret = 0;
@@ -250,6 +251,7 @@ static int __process_buffer(journal_t *journal, struct journal_head *jh,
 		transaction_t *t = jh->b_transaction;
 		tid_t tid = t->t_tid;
 
+		transaction->t_chp_stats.cs_forced_to_close++;
 		spin_unlock(&journal->j_list_lock);
 		jbd_unlock_bh_state(bh);
 		jbd2_log_start_commit(journal, tid);
@@ -279,6 +281,7 @@ static int __process_buffer(journal_t *journal, struct journal_head *jh,
 		bhs[*batch_count] = bh;
 		__buffer_relink_io(jh);
 		jbd_unlock_bh_state(bh);
+		transaction->t_chp_stats.cs_written++;
 		(*batch_count)++;
 		if (*batch_count == NR_BATCH) {
 			spin_unlock(&journal->j_list_lock);
@@ -322,6 +325,8 @@ int jbd2_log_do_checkpoint(journal_t *journal)
 	if (!journal->j_checkpoint_transactions)
 		goto out;
 	transaction = journal->j_checkpoint_transactions;
+	if (transaction->t_chp_stats.cs_chp_time == 0)
+		transaction->t_chp_stats.cs_chp_time = jiffies;
 	this_tid = transaction->t_tid;
 restart:
 	/*
@@ -346,7 +351,8 @@ restart:
 				retry = 1;
 				break;
 			}
-			retry = __process_buffer(journal, jh, bhs,&batch_count);
+			retry = __process_buffer(journal, jh, bhs, &batch_count,
+						 transaction);
 			if (!retry && lock_need_resched(&journal->j_list_lock)){
 				spin_unlock(&journal->j_list_lock);
 				retry = 1;
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 39b5cee..8749a86 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -20,6 +20,7 @@
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/pagemap.h>
+#include <linux/jiffies.h>
 
 /*
  * Default IO end handler for temporary BJ_IO buffer_heads.
@@ -290,6 +291,7 @@ static inline void write_tag_block(int tag_bytes, journal_block_tag_t *tag,
  */
 void jbd2_journal_commit_transaction(journal_t *journal)
 {
+	struct transaction_stats_s stats;
 	transaction_t *commit_transaction;
 	struct journal_head *jh, *new_jh, *descriptor;
 	struct buffer_head **wbuf = journal->j_wbuf;
@@ -337,6 +339,11 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	spin_lock(&journal->j_state_lock);
 	commit_transaction->t_state = T_LOCKED;
 
+	stats.u.run.rs_wait = commit_transaction->t_max_wait;
+	stats.u.run.rs_locked = jiffies;
+	stats.u.run.rs_running = jbd2_time_diff(commit_transaction->t_start,
+						stats.u.run.rs_locked);
+
 	spin_lock(&commit_transaction->t_handle_lock);
 	while (commit_transaction->t_updates) {
 		DEFINE_WAIT(wait);
@@ -407,6 +414,10 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	 */
 	jbd2_journal_switch_revoke_table(journal);
 
+	stats.u.run.rs_flushing = jiffies;
+	stats.u.run.rs_locked = jbd2_time_diff(stats.u.run.rs_locked,
+					       stats.u.run.rs_flushing);
+
 	commit_transaction->t_state = T_FLUSH;
 	journal->j_committing_transaction = commit_transaction;
 	journal->j_running_transaction = NULL;
@@ -498,6 +509,12 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	 */
 	commit_transaction->t_state = T_COMMIT;
 
+	stats.u.run.rs_logging = jiffies;
+	stats.u.run.rs_flushing = jbd2_time_diff(stats.u.run.rs_flushing,
+						 stats.u.run.rs_logging);
+	stats.u.run.rs_blocks = commit_transaction->t_outstanding_credits;
+	stats.u.run.rs_blocks_logged = 0;
+
 	descriptor = NULL;
 	bufs = 0;
 	while (commit_transaction->t_buffers) {
@@ -646,6 +663,7 @@ start_journal_io:
 				submit_bh(WRITE, bh);
 			}
 			cond_resched();
+			stats.u.run.rs_blocks_logged += bufs;
 
 			/* Force a new descriptor to be generated next
                            time round the loop. */
@@ -816,6 +834,7 @@ restart_loop:
 		cp_transaction = jh->b_cp_transaction;
 		if (cp_transaction) {
 			JBUFFER_TRACE(jh, "remove from old cp transaction");
+			cp_transaction->t_chp_stats.cs_dropped++;
 			__jbd2_journal_remove_checkpoint(jh);
 		}
 
@@ -890,6 +909,36 @@ restart_loop:
 
 	J_ASSERT(commit_transaction->t_state == T_COMMIT);
 
+	commit_transaction->t_start = jiffies;
+	stats.u.run.rs_logging = jbd2_time_diff(stats.u.run.rs_logging,
+						commit_transaction->t_start);
+
+	/*
+	 * File the transaction for history
+	 */
+	stats.ts_type = JBD2_STATS_RUN;
+	stats.ts_tid = commit_transaction->t_tid;
+	stats.u.run.rs_handle_count = commit_transaction->t_handle_count;
+	spin_lock(&journal->j_history_lock);
+	memcpy(journal->j_history + journal->j_history_cur, &stats,
+			sizeof(stats));
+	if (++journal->j_history_cur == journal->j_history_max)
+		journal->j_history_cur = 0;
+
+	/*
+	 * Calculate overall stats
+	 */
+	journal->j_stats.ts_tid++;
+	journal->j_stats.u.run.rs_wait += stats.u.run.rs_wait;
+	journal->j_stats.u.run.rs_running += stats.u.run.rs_running;
+	journal->j_stats.u.run.rs_locked += stats.u.run.rs_locked;
+	journal->j_stats.u.run.rs_flushing += stats.u.run.rs_flushing;
+	journal->j_stats.u.run.rs_logging += stats.u.run.rs_logging;
+	journal->j_stats.u.run.rs_handle_count += stats.u.run.rs_handle_count;
+	journal->j_stats.u.run.rs_blocks += stats.u.run.rs_blocks;
+	journal->j_stats.u.run.rs_blocks_logged += stats.u.run.rs_blocks_logged;
+	spin_unlock(&journal->j_history_lock);
+
 	commit_transaction->t_state = T_FINISHED;
 	J_ASSERT(commit_transaction == journal->j_committing_transaction);
 	journal->j_commit_sequence = commit_transaction->t_tid;
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 6ddc553..3667c91 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -36,6 +36,7 @@
 #include <linux/poison.h>
 #include <linux/proc_fs.h>
 #include <linux/debugfs.h>
+#include <linux/seq_file.h>
 
 #include <asm/uaccess.h>
 #include <asm/page.h>
@@ -640,6 +641,312 @@ struct journal_head *jbd2_journal_get_descriptor_buffer(journal_t *journal)
 	return jbd2_journal_add_journal_head(bh);
 }
 
+struct jbd2_stats_proc_session {
+	journal_t *journal;
+	struct transaction_stats_s *stats;
+	int start;
+	int max;
+};
+
+static void *jbd2_history_skip_empty(struct jbd2_stats_proc_session *s,
+					struct transaction_stats_s *ts,
+					int first)
+{
+	if (ts == s->stats + s->max)
+		ts = s->stats;
+	if (!first && ts == s->stats + s->start)
+		return NULL;
+	while (ts->ts_type == 0) {
+		ts++;
+		if (ts == s->stats + s->max)
+			ts = s->stats;
+		if (ts == s->stats + s->start)
+			return NULL;
+	}
+	return ts;
+
+}
+
+static void *jbd2_seq_history_start(struct seq_file *seq, loff_t *pos)
+{
+	struct jbd2_stats_proc_session *s = seq->private;
+	struct transaction_stats_s *ts;
+	int l = *pos;
+
+	if (l == 0)
+		return SEQ_START_TOKEN;
+	ts = jbd2_history_skip_empty(s, s->stats + s->start, 1);
+	if (!ts)
+		return NULL;
+	l--;
+	while (l) {
+		ts = jbd2_history_skip_empty(s, ++ts, 0);
+		if (!ts)
+			break;
+		l--;
+	}
+	return ts;
+}
+
+static void *jbd2_seq_history_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct jbd2_stats_proc_session *s = seq->private;
+	struct transaction_stats_s *ts = v;
+
+	++*pos;
+	if (v == SEQ_START_TOKEN)
+		return jbd2_history_skip_empty(s, s->stats + s->start, 1);
+	else
+		return jbd2_history_skip_empty(s, ++ts, 0);
+}
+
+static int jbd2_seq_history_show(struct seq_file *seq, void *v)
+{
+	struct transaction_stats_s *ts = v;
+	if (v == SEQ_START_TOKEN) {
+		seq_printf(seq, "%-4s %-5s %-5s %-5s %-5s %-5s %-5s %-6s %-5s "
+				"%-5s %-5s %-5s %-5s %-5s\n", "R/C", "tid",
+				"wait", "run", "lock", "flush", "log", "hndls",
+				"block", "inlog", "ctime", "write", "drop",
+				"close");
+		return 0;
+	}
+	if (ts->ts_type == JBD2_STATS_RUN)
+		seq_printf(seq, "%-4s %-5lu %-5u %-5u %-5u %-5u %-5u "
+				"%-6lu %-5lu %-5lu\n", "R", ts->ts_tid,
+				jiffies_to_msecs(ts->u.run.rs_wait),
+				jiffies_to_msecs(ts->u.run.rs_running),
+				jiffies_to_msecs(ts->u.run.rs_locked),
+				jiffies_to_msecs(ts->u.run.rs_flushing),
+				jiffies_to_msecs(ts->u.run.rs_logging),
+				ts->u.run.rs_handle_count,
+				ts->u.run.rs_blocks,
+				ts->u.run.rs_blocks_logged);
+	else if (ts->ts_type == JBD2_STATS_CHECKPOINT)
+		seq_printf(seq, "%-4s %-5lu %48s %-5u %-5lu %-5lu %-5lu\n",
+				"C", ts->ts_tid, " ",
+				jiffies_to_msecs(ts->u.chp.cs_chp_time),
+				ts->u.chp.cs_written, ts->u.chp.cs_dropped,
+				ts->u.chp.cs_forced_to_close);
+	else
+		J_ASSERT(0);
+	return 0;
+}
+
+static void jbd2_seq_history_stop(struct seq_file *seq, void *v)
+{
+}
+
+static struct seq_operations jbd2_seq_history_ops = {
+	.start  = jbd2_seq_history_start,
+	.next   = jbd2_seq_history_next,
+	.stop   = jbd2_seq_history_stop,
+	.show   = jbd2_seq_history_show,
+};
+
+static int jbd2_seq_history_open(struct inode *inode, struct file *file)
+{
+	journal_t *journal = PDE(inode)->data;
+	struct jbd2_stats_proc_session *s;
+	int rc, size;
+
+	s = kmalloc(sizeof(*s), GFP_KERNEL);
+	if (s == NULL)
+		return -ENOMEM;
+	size = sizeof(struct transaction_stats_s) * journal->j_history_max;
+	s->stats = kmalloc(size, GFP_KERNEL);
+	if (s->stats == NULL) {
+		kfree(s);
+		return -ENOMEM;
+	}
+	spin_lock(&journal->j_history_lock);
+	memcpy(s->stats, journal->j_history, size);
+	s->max = journal->j_history_max;
+	s->start = journal->j_history_cur % s->max;
+	spin_unlock(&journal->j_history_lock);
+
+	rc = seq_open(file, &jbd2_seq_history_ops);
+	if (rc == 0) {
+		struct seq_file *m = file->private_data;
+		m->private = s;
+	} else {
+		kfree(s->stats);
+		kfree(s);
+	}
+	return rc;
+
+}
+
+static int jbd2_seq_history_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq = file->private_data;
+	struct jbd2_stats_proc_session *s = seq->private;
+
+	kfree(s->stats);
+	kfree(s);
+	return seq_release(inode, file);
+}
+
+static struct file_operations jbd2_seq_history_fops = {
+	.owner		= THIS_MODULE,
+	.open           = jbd2_seq_history_open,
+	.read           = seq_read,
+	.llseek         = seq_lseek,
+	.release        = jbd2_seq_history_release,
+};
+
+static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos)
+{
+	return *pos ? NULL : SEQ_START_TOKEN;
+}
+
+static void *jbd2_seq_info_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	return NULL;
+}
+
+static int jbd2_seq_info_show(struct seq_file *seq, void *v)
+{
+	struct jbd2_stats_proc_session *s = seq->private;
+
+	if (v != SEQ_START_TOKEN)
+		return 0;
+	seq_printf(seq, "%lu transaction, each upto %u blocks\n",
+			s->stats->ts_tid,
+			s->journal->j_max_transaction_buffers);
+	if (s->stats->ts_tid == 0)
+		return 0;
+	seq_printf(seq, "average: \n  %ums waiting for transaction\n",
+	    jiffies_to_msecs(s->stats->u.run.rs_wait / s->stats->ts_tid));
+	seq_printf(seq, "  %ums running transaction\n",
+	    jiffies_to_msecs(s->stats->u.run.rs_running / s->stats->ts_tid));
+	seq_printf(seq, "  %ums transaction was being locked\n",
+	    jiffies_to_msecs(s->stats->u.run.rs_locked / s->stats->ts_tid));
+	seq_printf(seq, "  %ums flushing data (in ordered mode)\n",
+	    jiffies_to_msecs(s->stats->u.run.rs_flushing / s->stats->ts_tid));
+	seq_printf(seq, "  %ums logging transaction\n",
+	    jiffies_to_msecs(s->stats->u.run.rs_logging / s->stats->ts_tid));
+	seq_printf(seq, "  %lu handles per transaction\n",
+	    s->stats->u.run.rs_handle_count / s->stats->ts_tid);
+	seq_printf(seq, "  %lu blocks per transaction\n",
+	    s->stats->u.run.rs_blocks / s->stats->ts_tid);
+	seq_printf(seq, "  %lu logged blocks per transaction\n",
+	    s->stats->u.run.rs_blocks_logged / s->stats->ts_tid);
+	return 0;
+}
+
+static void jbd2_seq_info_stop(struct seq_file *seq, void *v)
+{
+}
+
+static struct seq_operations jbd2_seq_info_ops = {
+	.start  = jbd2_seq_info_start,
+	.next   = jbd2_seq_info_next,
+	.stop   = jbd2_seq_info_stop,
+	.show   = jbd2_seq_info_show,
+};
+
+static int jbd2_seq_info_open(struct inode *inode, struct file *file)
+{
+	journal_t *journal = PDE(inode)->data;
+	struct jbd2_stats_proc_session *s;
+	int rc, size;
+
+	s = kmalloc(sizeof(*s), GFP_KERNEL);
+	if (s == NULL)
+		return -ENOMEM;
+	size = sizeof(struct transaction_stats_s);
+	s->stats = kmalloc(size, GFP_KERNEL);
+	if (s->stats == NULL) {
+		kfree(s);
+		return -ENOMEM;
+	}
+	spin_lock(&journal->j_history_lock);
+	memcpy(s->stats, &journal->j_stats, size);
+	s->journal = journal;
+	spin_unlock(&journal->j_history_lock);
+
+	rc = seq_open(file, &jbd2_seq_info_ops);
+	if (rc == 0) {
+		struct seq_file *m = file->private_data;
+		m->private = s;
+	} else {
+		kfree(s->stats);
+		kfree(s);
+	}
+	return rc;
+
+}
+
+static int jbd2_seq_info_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq = file->private_data;
+	struct jbd2_stats_proc_session *s = seq->private;
+	kfree(s->stats);
+	kfree(s);
+	return seq_release(inode, file);
+}
+
+static struct file_operations jbd2_seq_info_fops = {
+	.owner		= THIS_MODULE,
+	.open           = jbd2_seq_info_open,
+	.read           = seq_read,
+	.llseek         = seq_lseek,
+	.release        = jbd2_seq_info_release,
+};
+
+static struct proc_dir_entry *proc_jbd2_stats;
+
+static void jbd2_stats_proc_init(journal_t *journal)
+{
+	char name[BDEVNAME_SIZE];
+
+	snprintf(name, sizeof(name) - 1, "%s", bdevname(journal->j_dev, name));
+	journal->j_proc_entry = proc_mkdir(name, proc_jbd2_stats);
+	if (journal->j_proc_entry) {
+		struct proc_dir_entry *p;
+		p = create_proc_entry("history", S_IRUGO,
+				journal->j_proc_entry);
+		if (p) {
+			p->proc_fops = &jbd2_seq_history_fops;
+			p->data = journal;
+			p = create_proc_entry("info", S_IRUGO,
+						journal->j_proc_entry);
+			if (p) {
+				p->proc_fops = &jbd2_seq_info_fops;
+				p->data = journal;
+			}
+		}
+	}
+}
+
+static void jbd2_stats_proc_exit(journal_t *journal)
+{
+	char name[BDEVNAME_SIZE];
+
+	snprintf(name, sizeof(name) - 1, "%s", bdevname(journal->j_dev, name));
+	remove_proc_entry("info", journal->j_proc_entry);
+	remove_proc_entry("history", journal->j_proc_entry);
+	remove_proc_entry(name, proc_jbd2_stats);
+}
+
+static void journal_init_stats(journal_t *journal)
+{
+	int size;
+
+	if (!proc_jbd2_stats)
+		return;
+
+	journal->j_history_max = 100;
+	size = sizeof(struct transaction_stats_s) * journal->j_history_max;
+	journal->j_history = kzalloc(size, GFP_KERNEL);
+	if (!journal->j_history) {
+		journal->j_history_max = 0;
+		return;
+	}
+	spin_lock_init(&journal->j_history_lock);
+}
+
 /*
  * Management for journal control blocks: functions to create and
  * destroy journal_t structures, and to initialise and read existing
@@ -681,6 +988,9 @@ static journal_t * journal_init_common (void)
 		kfree(journal);
 		goto fail;
 	}
+
+	journal_init_stats(journal);
+
 	return journal;
 fail:
 	return NULL;
@@ -735,6 +1045,7 @@ journal_t * jbd2_journal_init_dev(struct block_device *bdev,
 	journal->j_fs_dev = fs_dev;
 	journal->j_blk_offset = start;
 	journal->j_maxlen = len;
+	jbd2_stats_proc_init(journal);
 
 	bh = __getblk(journal->j_dev, start, journal->j_blocksize);
 	J_ASSERT(bh != NULL);
@@ -773,6 +1084,7 @@ journal_t * jbd2_journal_init_inode (struct inode *inode)
 
 	journal->j_maxlen = inode->i_size >> inode->i_sb->s_blocksize_bits;
 	journal->j_blocksize = inode->i_sb->s_blocksize;
+	jbd2_stats_proc_init(journal);
 
 	/* journal descriptor can store up to n blocks -bzzz */
 	n = journal->j_blocksize / sizeof(journal_block_tag_t);
@@ -1153,6 +1465,8 @@ void jbd2_journal_destroy(journal_t *journal)
 		brelse(journal->j_sb_buffer);
 	}
 
+	if (journal->j_proc_entry)
+		jbd2_stats_proc_exit(journal);
 	if (journal->j_inode)
 		iput(journal->j_inode);
 	if (journal->j_revoke)
@@ -1900,6 +2214,28 @@ static void __exit jbd2_remove_debugfs_entry(void)
 
 #endif
 
+#ifdef CONFIG_PROC_FS
+
+#define JBD2_STATS_PROC_NAME "fs/jbd2"
+
+static void __init jbd2_create_jbd_stats_proc_entry(void)
+{
+	proc_jbd2_stats = proc_mkdir(JBD2_STATS_PROC_NAME, NULL);
+}
+
+static void __exit jbd2_remove_jbd_stats_proc_entry(void)
+{
+	if (proc_jbd2_stats)
+		remove_proc_entry(JBD2_STATS_PROC_NAME, NULL);
+}
+
+#else
+
+#define jbd2_create_jbd_stats_proc_entry() do {} while (0)
+#define jbd2_remove_jbd_stats_proc_entry() do {} while (0)
+
+#endif
+
 struct kmem_cache *jbd2_handle_cache;
 
 static int __init journal_init_handle_cache(void)
@@ -1955,6 +2291,7 @@ static int __init journal_init(void)
 	if (ret != 0)
 		jbd2_journal_destroy_caches();
 	jbd2_create_debugfs_entry();
+	jbd2_create_jbd_stats_proc_entry();
 	return ret;
 }
 
@@ -1966,6 +2303,7 @@ static void __exit journal_exit(void)
 		printk(KERN_EMERG "JBD: leaked %d journal_heads!\n", n);
 #endif
 	jbd2_remove_debugfs_entry();
+	jbd2_remove_jbd_stats_proc_entry();
 	jbd2_journal_destroy_caches();
 }
 
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index b1fcf2b..f30802a 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -59,6 +59,8 @@ jbd2_get_transaction(journal_t *journal, transaction_t *transaction)
 
 	J_ASSERT(journal->j_running_transaction == NULL);
 	journal->j_running_transaction = transaction;
+	transaction->t_max_wait = 0;
+	transaction->t_start = jiffies;
 
 	return transaction;
 }
@@ -85,6 +87,7 @@ static int start_this_handle(journal_t *journal, handle_t *handle)
 	int nblocks = handle->h_buffer_credits;
 	transaction_t *new_transaction = NULL;
 	int ret = 0;
+	unsigned long ts = jiffies;
 
 	if (nblocks > journal->j_max_transaction_buffers) {
 		printk(KERN_ERR "JBD: %s wants too many credits (%d > %d)\n",
@@ -217,6 +220,12 @@ repeat_locked:
 	/* OK, account for the buffers that this operation expects to
 	 * use and add the handle to the running transaction. */
 
+	if (time_after(transaction->t_start, ts)) {
+		ts = jbd2_time_diff(ts, transaction->t_start);
+		if (ts > transaction->t_max_wait)
+			transaction->t_max_wait = ts;
+	}
+
 	handle->h_transaction = transaction;
 	transaction->t_outstanding_credits += nblocks;
 	transaction->t_updates++;