bcachefs: Disk space accounting rewrite

Main part of the disk accounting rewrite.

This is a wholesale rewrite of the existing disk space accounting, which
relies on percepu counters that are sharded by journal buffer, and
rolled up and added to each journal write.

With the new scheme, every set of counters is a distinct key in the
accounting btree; this fixes scaling limitations of the old scheme,
where counters took up space in each journal entry and required multiple
percpu counters.

Now, in memory accounting requires a single set of percpu counters - not
multiple for each in flight journal buffer - and in the future we'll
probably also have counters that don't use in memory percpu counters,
they're not strictly required.

An accounting update is now a normal btree update, using the btree write
buffer path. At transaction commit time, we apply accounting updates to
the in memory counters, which are percpu counters indexed in an
eytzinger tree by the accounting key.

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

1 files changed, 1 insertions, 25 deletions

diff --git a/fs/bcachefs/buckets.h b/fs/bcachefs/buckets.h
index 05a1c98754f2..b61942fc3090 100644
--- a/fs/bcachefs/buckets.h
+++ b/fs/bcachefs/buckets.h
@@ -212,7 +212,6 @@ static inline struct bch_dev_usage bch2_dev_usage_read(struct bch_dev *ca)
 	return ret;
 }
 
-void bch2_dev_usage_init(struct bch_dev *);
 void bch2_dev_usage_to_text(struct printbuf *, struct bch_dev_usage *);
 
 static inline u64 bch2_dev_buckets_reserved(struct bch_dev *ca, enum bch_watermark watermark)
@@ -315,29 +314,9 @@ bch2_fs_usage_read_short(struct bch_fs *);
 
 void bch2_dev_usage_update(struct bch_fs *, struct bch_dev *,
 			   const struct bch_alloc_v4 *,
-			   const struct bch_alloc_v4 *, u64, bool);
-
-/* key/bucket marking: */
-
-static inline struct bch_fs_usage *fs_usage_ptr(struct bch_fs *c,
-						unsigned journal_seq,
-						bool gc)
-{
-	percpu_rwsem_assert_held(&c->mark_lock);
-	BUG_ON(!gc && !journal_seq);
-
-	return this_cpu_ptr(gc
-			    ? c->usage_gc
-			    : c->usage[journal_seq & JOURNAL_BUF_MASK]);
-}
-
+			   const struct bch_alloc_v4 *);
 int bch2_update_replicas(struct bch_fs *, struct bkey_s_c,
-			 struct bch_replicas_entry_v1 *, s64,
-			 unsigned, bool);
-int bch2_update_replicas_list(struct btree_trans *,
 			 struct bch_replicas_entry_v1 *, s64);
-int bch2_update_cached_sectors_list(struct btree_trans *, unsigned, s64);
-int bch2_replicas_deltas_realloc(struct btree_trans *, unsigned);
 
 void bch2_fs_usage_initialize(struct bch_fs *);
 
@@ -369,9 +348,6 @@ int bch2_trigger_reservation(struct btree_trans *, enum btree_id, unsigned,
 
 void bch2_trans_account_disk_usage_change(struct btree_trans *);
 
-void bch2_trans_fs_usage_revert(struct btree_trans *, struct replicas_delta_list *);
-int bch2_trans_fs_usage_apply(struct btree_trans *, struct replicas_delta_list *);
-
 int bch2_trans_mark_metadata_bucket(struct btree_trans *, struct bch_dev *, u64,
 				    enum bch_data_type, unsigned,
 				    enum btree_iter_update_trigger_flags);