bcachefs: More open buckets

We need a larger open bucket reserve now that the btree interior update
path holds onto open bucket references; filesystems with many high
through devices may need more open buckets now.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/alloc_types.h

@@ -46,16 +46,22 @@ enum alloc_reserve {
 
 typedef FIFO(long)	alloc_fifo;
 
-/* Enough for 16 cache devices, 2 tiers and some left over for pipelining */
-#define OPEN_BUCKETS_COUNT	256
+#define OPEN_BUCKETS_COUNT	1024
 
 #define WRITE_POINT_HASH_NR	32
 #define WRITE_POINT_MAX		32
 
+typedef u16			open_bucket_idx_t;
+
 struct open_bucket {
 	spinlock_t		lock;
 	atomic_t		pin;
-	u8			freelist;
+	open_bucket_idx_t	freelist;
+
+	/*
+	 * When an open bucket has an ec_stripe attached, this is the index of
+	 * the block in the stripe this open_bucket corresponds to:
+	 */
 	u8			ec_idx;
 	u8			type;
 	unsigned		valid:1;
@@ -68,8 +74,8 @@ struct open_bucket {
 #define OPEN_BUCKET_LIST_MAX	15
 
 struct open_buckets {
-	u8			nr;
-	u8			v[OPEN_BUCKET_LIST_MAX];
+	open_bucket_idx_t	nr;
+	open_bucket_idx_t	v[OPEN_BUCKET_LIST_MAX];
 };
 
 struct dev_stripe_state {

fs/bcachefs/bcachefs.h

@@ -428,8 +428,8 @@ struct bch_dev {
 	alloc_fifo		free[RESERVE_NR];
 	alloc_fifo		free_inc;
 
-	u8			open_buckets_partial[OPEN_BUCKETS_COUNT];
-	unsigned		open_buckets_partial_nr;
+	open_bucket_idx_t	open_buckets_partial[OPEN_BUCKETS_COUNT];
+	open_bucket_idx_t	open_buckets_partial_nr;
 
 	size_t			fifo_last_bucket;
 
@@ -690,8 +690,8 @@ struct bch_fs {
 	struct closure_waitlist	freelist_wait;
 	u64			blocked_allocate;
 	u64			blocked_allocate_open_bucket;
-	u8			open_buckets_freelist;
-	u8			open_buckets_nr_free;
+	open_bucket_idx_t	open_buckets_freelist;
+	open_bucket_idx_t	open_buckets_nr_free;
 	struct closure_waitlist	open_buckets_wait;
 	struct open_bucket	open_buckets[OPEN_BUCKETS_COUNT];
 

fs/bcachefs/btree_update_interior.h

@@ -92,9 +92,9 @@ struct btree_update {
 	struct btree			*new_nodes[BTREE_UPDATE_NODES_MAX];
 	unsigned			nr_new_nodes;
 
-	u8				open_buckets[BTREE_UPDATE_NODES_MAX *
+	open_bucket_idx_t		open_buckets[BTREE_UPDATE_NODES_MAX *
 						     BCH_REPLICAS_MAX];
-	u8				nr_open_buckets;
+	open_bucket_idx_t		nr_open_buckets;
 
 	unsigned			journal_u64s;
 	u64				journal_entries[BTREE_UPDATE_JOURNAL_RES];