bcachefs: Improve trans->extra_journal_entries

Instead of using a darray, we now allocate journal entries for the
transaction commit path with our normal bump allocator - with an inlined
fastpath, and using btree_transaction_stats to remember how much to
initially allocate so as to avoid transaction restarts.

This is prep work for converting write buffer updates to use this
mechanism.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/bcachefs/bcachefs.h b/fs/bcachefs/bcachefs.h
index f33f510463d1..ce66894e6537 100644
--- a/fs/bcachefs/bcachefs.h
+++ b/fs/bcachefs/bcachefs.h
@@ -638,6 +638,7 @@ struct btree_transaction_stats {
 	struct mutex		lock;
 	unsigned		nr_max_paths;
 	unsigned		wb_updates_size;
+	unsigned		journal_entries_size;
 	unsigned		max_mem;
 	char			*max_paths_text;
 };