bcachefs: Improved btree write statistics

This replaces sysfs btree_avg_write_size with btree_write_stats, which
now breaks out statistics by the source of the btree write.

Btree writes that are too small are a source of inefficiency, and
excessive btree resort overhead - this will let us see what's causing
them.

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

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/bcachefs/btree_types.h b/fs/bcachefs/btree_types.h
index ea844dd7a16b..38c4754dbd7e 100644
--- a/fs/bcachefs/btree_types.h
+++ b/fs/bcachefs/btree_types.h
@@ -77,6 +77,7 @@ struct btree {
 	u8			nsets;
 	u8			nr_key_bits;
 	u16			version_ondisk;
+	u8			write_type;
 
 	struct bkey_format	format;