bcache: Refactor bset_tree sysfs stats

We're in the process of turning bset.c into library code, so none of the code in
that file should know about struct cache_set or struct btree - so, move the
btree traversal part of the stats code to sysfs.c.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>

drivers/md/bcache/bset.c

@@ -1122,29 +1122,16 @@ void bch_btree_sort_lazy(struct btree *b, struct bset_sort_state *state)
 }
 EXPORT_SYMBOL(bch_btree_sort_lazy);
 
-/* Sysfs stuff */
-
-struct bset_stats {
-	struct btree_op op;
-	size_t nodes;
-	size_t sets_written, sets_unwritten;
-	size_t bytes_written, bytes_unwritten;
-	size_t floats, failed;
-};
-
-static int btree_bset_stats(struct btree_op *op, struct btree *b)
+void bch_btree_keys_stats(struct btree_keys *b, struct bset_stats *stats)
 {
-	struct bset_stats *stats = container_of(op, struct bset_stats, op);
 	unsigned i;
 
-	stats->nodes++;
-
-	for (i = 0; i <= b->keys.nsets; i++) {
-		struct bset_tree *t = &b->keys.set[i];
+	for (i = 0; i <= b->nsets; i++) {
+		struct bset_tree *t = &b->set[i];
 		size_t bytes = t->data->keys * sizeof(uint64_t);
 		size_t j;
 
-		if (bset_written(&b->keys, t)) {
+		if (bset_written(b, t)) {
 			stats->sets_written++;
 			stats->bytes_written += bytes;
 
@@ -1158,32 +1145,4 @@ static int btree_bset_stats(struct btree_op *op, struct btree *b)
 			stats->bytes_unwritten += bytes;
 		}
 	}
-
-	return MAP_CONTINUE;
-}
-
-int bch_bset_print_stats(struct cache_set *c, char *buf)
-{
-	struct bset_stats t;
-	int ret;
-
-	memset(&t, 0, sizeof(struct bset_stats));
-	bch_btree_op_init(&t.op, -1);
-
-	ret = bch_btree_map_nodes(&t.op, c, &ZERO_KEY, btree_bset_stats);
-	if (ret < 0)
-		return ret;
-
-	return snprintf(buf, PAGE_SIZE,
-			"btree nodes:		%zu\n"
-			"written sets:		%zu\n"
-			"unwritten sets:		%zu\n"
-			"written key bytes:	%zu\n"
-			"unwritten key bytes:	%zu\n"
-			"floats:			%zu\n"
-			"failed:			%zu\n",
-			t.nodes,
-			t.sets_written, t.sets_unwritten,
-			t.bytes_written, t.bytes_unwritten,
-			t.floats, t.failed);
 }

drivers/md/bcache/bset.h

@@ -365,6 +365,14 @@ static inline void bch_btree_sort(struct btree *b,
 	bch_btree_sort_partial(b, 0, state);
 }
 
+struct bset_stats {
+	size_t sets_written, sets_unwritten;
+	size_t bytes_written, bytes_unwritten;
+	size_t floats, failed;
+};
+
+void bch_btree_keys_stats(struct btree_keys *, struct bset_stats *);
+
 /* Bkey utility code */
 
 #define bset_bkey_last(i)	bkey_idx((struct bkey *) (i)->d, (i)->keys)
@@ -495,6 +503,4 @@ int __bch_keylist_realloc(struct keylist *, unsigned);
 struct cache_set;
 const char *bch_ptr_status(struct cache_set *, const struct bkey *);
 
-int bch_bset_print_stats(struct cache_set *, char *);
-
 #endif

drivers/md/bcache/sysfs.c

@@ -400,6 +400,48 @@ static struct attribute *bch_flash_dev_files[] = {
 };
 KTYPE(bch_flash_dev);
 
+struct bset_stats_op {
+	struct btree_op op;
+	size_t nodes;
+	struct bset_stats stats;
+};
+
+static int btree_bset_stats(struct btree_op *b_op, struct btree *b)
+{
+	struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
+
+	op->nodes++;
+	bch_btree_keys_stats(&b->keys, &op->stats);
+
+	return MAP_CONTINUE;
+}
+
+int bch_bset_print_stats(struct cache_set *c, char *buf)
+{
+	struct bset_stats_op op;
+	int ret;
+
+	memset(&op, 0, sizeof(op));
+	bch_btree_op_init(&op.op, -1);
+
+	ret = bch_btree_map_nodes(&op.op, c, &ZERO_KEY, btree_bset_stats);
+	if (ret < 0)
+		return ret;
+
+	return snprintf(buf, PAGE_SIZE,
+			"btree nodes:		%zu\n"
+			"written sets:		%zu\n"
+			"unwritten sets:		%zu\n"
+			"written key bytes:	%zu\n"
+			"unwritten key bytes:	%zu\n"
+			"floats:			%zu\n"
+			"failed:			%zu\n",
+			op.nodes,
+			op.stats.sets_written, op.stats.sets_unwritten,
+			op.stats.bytes_written, op.stats.bytes_unwritten,
+			op.stats.floats, op.stats.failed);
+}
+
 SHOW(__bch_cache_set)
 {
 	unsigned root_usage(struct cache_set *c)