linux/fs/bcachefs/btree_cache.h
Kent Overstreet f270667a7f bcachefs: Slightly reduce btree split threshold
2/3rds performs a lot better than 3/4ths on the tested workloda, leading
to significanly fewer btree node compactions.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:38 -04:00

110 lines
3.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_BTREE_CACHE_H
#define _BCACHEFS_BTREE_CACHE_H
#include "bcachefs.h"
#include "btree_types.h"
struct btree_iter;
extern const char * const bch2_btree_ids[];
void bch2_recalc_btree_reserve(struct bch_fs *);
void bch2_btree_node_hash_remove(struct btree_cache *, struct btree *);
int __bch2_btree_node_hash_insert(struct btree_cache *, struct btree *);
int bch2_btree_node_hash_insert(struct btree_cache *, struct btree *,
unsigned, enum btree_id);
void bch2_btree_cache_cannibalize_unlock(struct bch_fs *);
int bch2_btree_cache_cannibalize_lock(struct bch_fs *, struct closure *);
struct btree *bch2_btree_node_mem_alloc(struct bch_fs *);
struct btree *bch2_btree_node_get(struct bch_fs *, struct btree_iter *,
const struct bkey_i *, unsigned,
enum six_lock_type);
struct btree *bch2_btree_node_get_noiter(struct bch_fs *, const struct bkey_i *,
enum btree_id, unsigned);
struct btree *bch2_btree_node_get_sibling(struct bch_fs *, struct btree_iter *,
struct btree *, enum btree_node_sibling);
void bch2_btree_node_prefetch(struct bch_fs *, struct btree_iter *,
const struct bkey_i *, unsigned);
void bch2_fs_btree_cache_exit(struct bch_fs *);
int bch2_fs_btree_cache_init(struct bch_fs *);
void bch2_fs_btree_cache_init_early(struct btree_cache *);
static inline u64 btree_ptr_hash_val(const struct bkey_i *k)
{
switch (k->k.type) {
case KEY_TYPE_btree_ptr:
return *((u64 *) bkey_i_to_btree_ptr_c(k)->v.start);
case KEY_TYPE_btree_ptr_v2:
return bkey_i_to_btree_ptr_v2_c(k)->v.seq;
default:
return 0;
}
}
static inline struct btree *btree_node_mem_ptr(const struct bkey_i *k)
{
return k->k.type == KEY_TYPE_btree_ptr_v2
? (void *)(unsigned long)bkey_i_to_btree_ptr_v2_c(k)->v.mem_ptr
: NULL;
}
/* is btree node in hash table? */
static inline bool btree_node_hashed(struct btree *b)
{
return b->hash_val != 0;
}
#define for_each_cached_btree(_b, _c, _tbl, _iter, _pos) \
for ((_tbl) = rht_dereference_rcu((_c)->btree_cache.table.tbl, \
&(_c)->btree_cache.table), \
_iter = 0; _iter < (_tbl)->size; _iter++) \
rht_for_each_entry_rcu((_b), (_pos), _tbl, _iter, hash)
static inline size_t btree_bytes(struct bch_fs *c)
{
return c->opts.btree_node_size << 9;
}
static inline size_t btree_max_u64s(struct bch_fs *c)
{
return (btree_bytes(c) - sizeof(struct btree_node)) / sizeof(u64);
}
static inline size_t btree_page_order(struct bch_fs *c)
{
return get_order(btree_bytes(c));
}
static inline size_t btree_pages(struct bch_fs *c)
{
return 1 << btree_page_order(c);
}
static inline unsigned btree_blocks(struct bch_fs *c)
{
return c->opts.btree_node_size >> c->block_bits;
}
#define BTREE_SPLIT_THRESHOLD(c) (btree_max_u64s(c) * 2 / 3)
#define BTREE_FOREGROUND_MERGE_THRESHOLD(c) (btree_max_u64s(c) * 1 / 3)
#define BTREE_FOREGROUND_MERGE_HYSTERESIS(c) \
(BTREE_FOREGROUND_MERGE_THRESHOLD(c) + \
(BTREE_FOREGROUND_MERGE_THRESHOLD(c) << 2))
#define btree_node_root(_c, _b) ((_c)->btree_roots[(_b)->c.btree_id].b)
void bch2_btree_node_to_text(struct printbuf *, struct bch_fs *,
struct btree *);
#endif /* _BCACHEFS_BTREE_CACHE_H */