5 files changed, 20 insertions, 13 deletions

diff --git a/fs/bcachefs/bcachefs.h b/fs/bcachefs/bcachefs.h
index bc27e2cfc8a7..5e6620c0889f 100644
--- a/fs/bcachefs/bcachefs.h
+++ b/fs/bcachefs/bcachefs.h
@@ -533,6 +533,7 @@ struct btree_transaction_stats {
 	struct mutex		lock;
 	struct bch2_time_stats       lock_hold_times;
 	unsigned		nr_max_paths;
+	unsigned		max_mem;
 	char			*max_paths_text;
 };
 
diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index 1ae860ffd3cb..10bce0540261 100644
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -2747,9 +2747,11 @@ void bch2_trans_copy_iter(struct btree_iter *dst, struct btree_iter *src)
 
 void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
 {
-	size_t new_top = trans->mem_top + size;
+	unsigned new_top = trans->mem_top + size;
 	void *p;
 
+	trans->mem_max = max(trans->mem_max, new_top);
+
 	if (new_top > trans->mem_bytes) {
 		size_t old_bytes = trans->mem_bytes;
 		size_t new_bytes = roundup_pow_of_two(new_top);
@@ -2887,10 +2889,7 @@ static inline unsigned bch2_trans_get_fn_idx(struct btree_trans *trans, struct b
 	return i;
 }
 
-void __bch2_trans_init(struct btree_trans *trans, struct bch_fs *c,
-		       unsigned expected_nr_iters,
-		       size_t expected_mem_bytes,
-		       const char *fn)
+void __bch2_trans_init(struct btree_trans *trans, struct bch_fs *c, const char *fn)
 	__acquires(&c->btree_trans_barrier)
 {
 	struct btree_transaction_stats *s;
@@ -2908,8 +2907,10 @@ void __bch2_trans_init(struct btree_trans *trans, struct bch_fs *c,
 
 	bch2_trans_alloc_paths(trans, c);
 
-	if (expected_mem_bytes) {
-		expected_mem_bytes = roundup_pow_of_two(expected_mem_bytes);
+	s = btree_trans_stats(trans);
+	if (s) {
+		unsigned expected_mem_bytes = roundup_pow_of_two(s->max_mem);
+
 		trans->mem = kmalloc(expected_mem_bytes, GFP_KERNEL);
 
 		if (!unlikely(trans->mem)) {
@@ -2918,11 +2919,9 @@ void __bch2_trans_init(struct btree_trans *trans, struct bch_fs *c,
 		} else {
 			trans->mem_bytes = expected_mem_bytes;
 		}
-	}
 
-	s = btree_trans_stats(trans);
-	if (s)
 		trans->nr_max_paths = s->nr_max_paths;
+	}
 
 	trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
 
@@ -2969,9 +2968,13 @@ void bch2_trans_exit(struct btree_trans *trans)
 {
 	struct btree_insert_entry *i;
 	struct bch_fs *c = trans->c;
+	struct btree_transaction_stats *s = btree_trans_stats(trans);
 
 	bch2_trans_unlock(trans);
 
+	if (s)
+		s->max_mem = max(s->max_mem, trans->mem_max);
+
 	trans_for_each_update(trans, i)
 		__btree_path_put(i->path, true);
 	trans->nr_updates		= 0;
diff --git a/fs/bcachefs/btree_iter.h b/fs/bcachefs/btree_iter.h
index c25ad7728cd1..ab680e14a6cc 100644
--- a/fs/bcachefs/btree_iter.h
+++ b/fs/bcachefs/btree_iter.h
@@ -565,11 +565,10 @@ void bch2_btree_path_to_text(struct printbuf *, struct btree_path *);
 void bch2_trans_paths_to_text(struct printbuf *, struct btree_trans *);
 void bch2_dump_trans_updates(struct btree_trans *);
 void bch2_dump_trans_paths_updates(struct btree_trans *);
-void __bch2_trans_init(struct btree_trans *, struct bch_fs *,
-		       unsigned, size_t, const char *);
+void __bch2_trans_init(struct btree_trans *, struct bch_fs *, const char *);
 void bch2_trans_exit(struct btree_trans *);
 
-#define bch2_trans_init(...)	__bch2_trans_init(__VA_ARGS__, __func__)
+#define bch2_trans_init(_trans, _c, _nr_iters, _mem) __bch2_trans_init(_trans, _c, __func__)
 
 void bch2_btree_trans_to_text(struct printbuf *, struct btree_trans *);
 
diff --git a/fs/bcachefs/btree_types.h b/fs/bcachefs/btree_types.h
index 98479d5be66f..dc46afbd9798 100644
--- a/fs/bcachefs/btree_types.h
+++ b/fs/bcachefs/btree_types.h
@@ -421,6 +421,7 @@ struct btree_trans {
 	u64			paths_allocated;
 
 	unsigned		mem_top;
+	unsigned		mem_max;
 	unsigned		mem_bytes;
 	void			*mem;
 
diff --git a/fs/bcachefs/debug.c b/fs/bcachefs/debug.c
index 86c4b023ac7c..4fe20d36212e 100644
--- a/fs/bcachefs/debug.c
+++ b/fs/bcachefs/debug.c
@@ -667,6 +667,9 @@ static ssize_t lock_held_stats_read(struct file *file, char __user *buf,
 
 		mutex_lock(&s->lock);
 
+		prt_printf(&i->buf, "Max mem used: %u", s->max_mem);
+		prt_newline(&i->buf);
+
 		if (IS_ENABLED(CONFIG_BCACHEFS_LOCK_TIME_STATS)) {
 			prt_printf(&i->buf, "Lock hold times:");
 			prt_newline(&i->buf);