Commit 9ab55df5 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Walk leaf to root in btree_gc 



Next change will move gc_alloc_start initialization into the alloc
trigger, so we have to mark those first.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 86d46471

fs/bcachefs/btree_gc.c

+17 −20
Original line number Diff line number Diff line
@@ -635,13 +635,27 @@ static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id, 
static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree, bool initial)

{

	struct bch_fs *c = trans->c;

	int level = 0, target_depth = btree_node_type_needs_gc(__btree_node_type(0, btree)) ? 0 : 1;

	unsigned target_depth = btree_node_type_needs_gc(__btree_node_type(0, btree)) ? 0 : 1;

	int ret = 0;



	/* We need to make sure every leaf node is readable before going RW */

	if (initial)

		target_depth = 0;



	for (unsigned level = target_depth; level < BTREE_MAX_DEPTH; level++) {

		struct btree *prev = NULL;

		struct btree_iter iter;

		bch2_trans_node_iter_init(trans, &iter, btree, POS_MIN, 0, level,

					  BTREE_ITER_prefetch);



		ret = for_each_btree_key_continue(trans, iter, 0, k, ({

			gc_pos_set(c, gc_pos_btree(btree, level, k.k->p));

			bch2_gc_mark_key(trans, btree, level, &prev, &iter, k, initial);

		}));

		if (ret)

			goto err;

	}



	/* root */

	do {

retry_root:
@@ -663,28 +677,11 @@ static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree, bool in 
		gc_pos_set(c, gc_pos_btree(btree, b->c.level + 1, SPOS_MAX));

		struct bkey_s_c k = bkey_i_to_s_c(&b->key);

		ret = bch2_gc_mark_key(trans, btree, b->c.level + 1, NULL, NULL, k, initial);

		level = b->c.level;

err_root:

		bch2_trans_iter_exit(trans, &iter);

	} while (bch2_err_matches(ret, BCH_ERR_transaction_restart));



	if (ret)

		return ret;



	for (; level >= target_depth; --level) {

		struct btree *prev = NULL;

		struct btree_iter iter;

		bch2_trans_node_iter_init(trans, &iter, btree, POS_MIN, 0, level,

					  BTREE_ITER_prefetch);



		ret = for_each_btree_key_continue(trans, iter, 0, k, ({

			gc_pos_set(c, gc_pos_btree(btree, level, k.k->p));

			bch2_gc_mark_key(trans, btree, level, &prev, &iter, k, initial);

		}));

		if (ret)

			break;

	}



err:

	bch_err_fn(c, ret);

	return ret;

}

fs/bcachefs/btree_gc.h

+7 −5
Original line number Diff line number Diff line
@@ -58,6 +58,8 @@ static inline struct gc_pos gc_pos_btree_node(struct btree *b) 


static inline int gc_btree_order(enum btree_id btree)

{

	if (btree == BTREE_ID_alloc)

		return -2;

	if (btree == BTREE_ID_stripes)

		return -1;

	return btree;
@@ -68,7 +70,7 @@ static inline int gc_pos_cmp(struct gc_pos l, struct gc_pos r) 
	return  cmp_int(l.phase, r.phase) ?:

		cmp_int(gc_btree_order(l.btree),

			gc_btree_order(r.btree)) ?:

		-cmp_int(l.level, r.level) ?:

		cmp_int(l.level, r.level) ?:

		bpos_cmp(l.pos, r.pos);

}