bcachefs: do_rebalance_scan() now only updates bch_extent_rebalance

This ensures that our pending rebalance work accounting is accurate
quickly.

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

diff --git a/fs/bcachefs/move.c b/fs/bcachefs/move.c
index 3a92eced2e67b11eb93f5cd2dea18ac986a2f142..49898d5743d4b8ff68467864692d4f0b0a304d1a 100644 (file)
--- a/fs/bcachefs/move.c
+++ b/fs/bcachefs/move.c
@@ -412,7 +412,7 @@ err:
        return ret;
 }
 
-static struct bch_io_opts *bch2_move_get_io_opts(struct btree_trans *trans,
+struct bch_io_opts *bch2_move_get_io_opts(struct btree_trans *trans,
                          struct per_snapshot_io_opts *io_opts,
                          struct bpos extent_pos, /* extent_iter, extent_k may be in reflink btree */
                          struct btree_iter *extent_iter,

diff --git a/fs/bcachefs/move.h b/fs/bcachefs/move.h
index fb38383ffc7b7d769bd8491b970fc502016e1ce3..86b80499ac55f221c15d7107bbfe0fa4c2187871 100644 (file)
--- a/fs/bcachefs/move.h
+++ b/fs/bcachefs/move.h
@@ -122,6 +122,10 @@ int bch2_move_extent(struct moving_context *,
                     struct bch_io_opts,
                     struct data_update_opts);
 
+struct bch_io_opts *bch2_move_get_io_opts(struct btree_trans *,
+                         struct per_snapshot_io_opts *, struct bpos,
+                         struct btree_iter *, struct bkey_s_c);
+
 int bch2_move_data_btree(struct moving_context *, struct bpos, struct bpos,
                         move_pred_fn, void *, enum btree_id, unsigned);
 int __bch2_move_data(struct moving_context *,

diff --git a/fs/bcachefs/rebalance.c b/fs/bcachefs/rebalance.c
index 8fefe2b174c2af0d89c826f0abaad56e73c7473c..c223bb092d33010c6993071d2214755a0d6b4471 100644 (file)
--- a/fs/bcachefs/rebalance.c
+++ b/fs/bcachefs/rebalance.c
@@ -459,22 +459,11 @@ out:
        return ret;
 }
 
-static bool rebalance_pred(struct bch_fs *c, void *arg,
-                          enum btree_id btree, struct bkey_s_c k,
-                          struct bch_io_opts *io_opts,
-                          struct data_update_opts *data_opts)
-{
-       data_opts->rewrite_ptrs         = bch2_bkey_ptrs_need_rebalance(c, io_opts, k);
-       data_opts->target               = io_opts->background_target;
-       data_opts->write_flags          |= BCH_WRITE_only_specified_devs;
-       return data_opts->rewrite_ptrs != 0;
-}
-
 static int do_rebalance_scan(struct moving_context *ctxt, u64 inum, u64 cookie)
 {
        struct btree_trans *trans = ctxt->trans;
+       struct bch_fs *c = trans->c;
        struct bch_fs_rebalance *r = &trans->c->rebalance;
-       int ret;
 
        bch2_move_stats_init(&r->scan_stats, "rebalance_scan");
        ctxt->stats = &r->scan_stats;
@@ -489,11 +478,34 @@ static int do_rebalance_scan(struct moving_context *ctxt, u64 inum, u64 cookie)
 
        r->state = BCH_REBALANCE_scanning;
 
-       ret = __bch2_move_data(ctxt, r->scan_start, r->scan_end, rebalance_pred, NULL) ?:
-               commit_do(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
-                         bch2_clear_rebalance_needs_scan(trans, inum, cookie));
+       struct per_snapshot_io_opts snapshot_io_opts;
+       per_snapshot_io_opts_init(&snapshot_io_opts, c);
+
+       int ret = for_each_btree_key_max(trans, iter, BTREE_ID_extents,
+                                     r->scan_start.pos, r->scan_end.pos,
+                                     BTREE_ITER_all_snapshots|
+                                     BTREE_ITER_not_extents|
+                                     BTREE_ITER_prefetch, k, ({
+               ctxt->stats->pos = BBPOS(iter.btree_id, iter.pos);
 
+               struct bch_io_opts *io_opts = bch2_move_get_io_opts(trans,
+                                       &snapshot_io_opts, iter.pos, &iter, k);
+               PTR_ERR_OR_ZERO(io_opts);
+       })) ?:
+       commit_do(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
+                 bch2_clear_rebalance_needs_scan(trans, inum, cookie));
+
+       per_snapshot_io_opts_exit(&snapshot_io_opts);
        bch2_move_stats_exit(&r->scan_stats, trans->c);
+
+       /*
+        * Ensure that the rebalance_work entries we created are seen by the
+        * next iteration of do_rebalance(), so we don't end up stuck in
+        * rebalance_wait():
+        */
+       atomic64_inc(&r->scan_stats.sectors_seen);
+       bch2_btree_write_buffer_flush_sync(trans);
+
        return ret;
 }