bcache: Add bch_btree_keys_u64s_remaining()

Helper function to explicitly check how much space is free in a btree node

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
This commit is contained in:
Kent Overstreet 2013-11-11 19:03:54 -08:00
parent a85e968e66
commit 59158fde42
3 changed files with 31 additions and 13 deletions

View File

@ -260,6 +260,21 @@ static inline bool btree_keys_expensive_checks(struct btree_keys *b)
#define set_blocks(i, block_bytes) \
__set_blocks(i, (i)->keys, block_bytes)
static inline size_t bch_btree_keys_u64s_remaining(struct btree_keys *b)
{
struct bset_tree *t = bset_tree_last(b);
BUG_ON((PAGE_SIZE << b->page_order) <
(bset_byte_offset(b, t->data) + set_bytes(t->data)));
if (!b->last_set_unwritten)
return 0;
return ((PAGE_SIZE << b->page_order) -
(bset_byte_offset(b, t->data) + set_bytes(t->data))) /
sizeof(u64);
}
static inline struct bset *bset_next_set(struct btree_keys *b,
unsigned block_bytes)
{

View File

@ -179,14 +179,6 @@ static inline struct bset *write_block(struct btree *b)
return ((void *) btree_bset_first(b)) + b->written * block_bytes(b->c);
}
static inline bool should_split(struct btree *b)
{
struct bset *i = write_block(b);
return b->written >= btree_blocks(b) ||
(b->written + __set_blocks(i, i->keys + 15, block_bytes(b->c))
> btree_blocks(b));
}
/* Btree key manipulation */
void bkey_put(struct cache_set *c, struct bkey *k)
@ -2026,6 +2018,19 @@ merged:
return true;
}
static size_t insert_u64s_remaining(struct btree *b)
{
ssize_t ret = bch_btree_keys_u64s_remaining(&b->keys);
/*
* Might land in the middle of an existing extent and have to split it
*/
if (b->keys.ops->is_extents)
ret -= KEY_MAX_U64S;
return max(ret, 0L);
}
static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op,
struct keylist *insert_keys,
struct bkey *replace_key)
@ -2034,12 +2039,9 @@ static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op,
int oldsize = bch_count_data(b);
while (!bch_keylist_empty(insert_keys)) {
struct bset *i = write_block(b);
struct bkey *k = insert_keys->keys;
if (b->written +
__set_blocks(i, i->keys + bkey_u64s(k),
block_bytes(b->c)) > btree_blocks(b))
if (bkey_u64s(k) > insert_u64s_remaining(b))
break;
if (bkey_cmp(k, &b->key) <= 0) {
@ -2203,7 +2205,7 @@ static int bch_btree_insert_node(struct btree *b, struct btree_op *op,
{
BUG_ON(b->level && replace_key);
if (should_split(b)) {
if (bch_keylist_nkeys(insert_keys) > insert_u64s_remaining(b)) {
if (current->bio_list) {
op->lock = b->c->root->level + 1;
return -EAGAIN;

View File

@ -39,6 +39,7 @@ static inline void SET_##name(struct bkey *k, unsigned i, __u64 v) \
}
#define KEY_SIZE_BITS 16
#define KEY_MAX_U64S 8
KEY_FIELD(KEY_PTRS, high, 60, 3)
KEY_FIELD(HEADER_SIZE, high, 58, 2)