bcachefs: Convert gc_alloc_start() to for_each_btree_key2()

This eliminates some SRCU warnings: for_each_btree_key2() runs every
loop iteration in a distinct transaction context.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c
index 0b5d09c8475d00bf35ee70c52cd9ae9483a56823..30ab78a24517404b35d3e41d8a86482f7e719096 100644 (file)
--- a/fs/bcachefs/btree_gc.c
+++ b/fs/bcachefs/btree_gc.c
@@ -1541,8 +1541,8 @@ static int bch2_gc_alloc_start(struct bch_fs *c, bool metadata_only)
                rcu_assign_pointer(ca->buckets_gc, buckets);
        }
 
-       for_each_btree_key(trans, iter, BTREE_ID_alloc, POS_MIN,
-                          BTREE_ITER_PREFETCH, k, ret) {
+       ret = for_each_btree_key2(trans, iter, BTREE_ID_alloc, POS_MIN,
+                                 BTREE_ITER_PREFETCH, k, ({
                ca = bch_dev_bkey_exists(c, k.k->p.inode);
                g = gc_bucket(ca, k.k->p.offset);
 
@@ -1561,8 +1561,9 @@ static int bch2_gc_alloc_start(struct bch_fs *c, bool metadata_only)
                        g->stripe               = a->stripe;
                        g->stripe_redundancy    = a->stripe_redundancy;
                }
-       }
-       bch2_trans_iter_exit(trans, &iter);
+
+               0;
+       }));
 err:
        bch2_trans_put(trans);
        if (ret)