baa6502905
We're seeing livelocks that appear to be due to bch2_btree_key_cache_scan repeatedly scanning and blocking other tasks from using the key cache lock - we probably shouldn't be reporting objects that can't actually be freed yet. Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
743 lines
17 KiB
C
743 lines
17 KiB
C
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#include "bcachefs.h"
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#include "btree_cache.h"
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#include "btree_iter.h"
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#include "btree_key_cache.h"
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#include "btree_locking.h"
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#include "btree_update.h"
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#include "error.h"
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#include "journal.h"
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#include "journal_reclaim.h"
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#include "trace.h"
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#include <linux/sched/mm.h>
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static struct kmem_cache *bch2_key_cache;
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static int bch2_btree_key_cache_cmp_fn(struct rhashtable_compare_arg *arg,
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const void *obj)
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{
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const struct bkey_cached *ck = obj;
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const struct bkey_cached_key *key = arg->key;
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return cmp_int(ck->key.btree_id, key->btree_id) ?:
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bpos_cmp(ck->key.pos, key->pos);
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}
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static const struct rhashtable_params bch2_btree_key_cache_params = {
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.head_offset = offsetof(struct bkey_cached, hash),
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.key_offset = offsetof(struct bkey_cached, key),
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.key_len = sizeof(struct bkey_cached_key),
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.obj_cmpfn = bch2_btree_key_cache_cmp_fn,
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};
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__flatten
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inline struct bkey_cached *
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bch2_btree_key_cache_find(struct bch_fs *c, enum btree_id btree_id, struct bpos pos)
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{
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struct bkey_cached_key key = {
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.btree_id = btree_id,
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.pos = pos,
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};
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return rhashtable_lookup_fast(&c->btree_key_cache.table, &key,
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bch2_btree_key_cache_params);
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}
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static bool bkey_cached_lock_for_evict(struct bkey_cached *ck)
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{
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if (!six_trylock_intent(&ck->c.lock))
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return false;
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if (!six_trylock_write(&ck->c.lock)) {
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six_unlock_intent(&ck->c.lock);
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return false;
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}
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if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
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six_unlock_write(&ck->c.lock);
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six_unlock_intent(&ck->c.lock);
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return false;
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}
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return true;
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}
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static void bkey_cached_evict(struct btree_key_cache *c,
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struct bkey_cached *ck)
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{
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BUG_ON(rhashtable_remove_fast(&c->table, &ck->hash,
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bch2_btree_key_cache_params));
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memset(&ck->key, ~0, sizeof(ck->key));
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atomic_long_dec(&c->nr_keys);
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}
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static void bkey_cached_free(struct btree_key_cache *bc,
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struct bkey_cached *ck)
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{
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struct bch_fs *c = container_of(bc, struct bch_fs, btree_key_cache);
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BUG_ON(test_bit(BKEY_CACHED_DIRTY, &ck->flags));
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ck->btree_trans_barrier_seq =
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start_poll_synchronize_srcu(&c->btree_trans_barrier);
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list_move_tail(&ck->list, &bc->freed);
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bc->nr_freed++;
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kfree(ck->k);
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ck->k = NULL;
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ck->u64s = 0;
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six_unlock_write(&ck->c.lock);
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six_unlock_intent(&ck->c.lock);
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}
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static struct bkey_cached *
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bkey_cached_alloc(struct btree_key_cache *c)
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{
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struct bkey_cached *ck;
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ck = kmem_cache_alloc(bch2_key_cache, GFP_NOFS|__GFP_ZERO);
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if (likely(ck)) {
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INIT_LIST_HEAD(&ck->list);
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six_lock_init(&ck->c.lock);
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lockdep_set_novalidate_class(&ck->c.lock);
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BUG_ON(!six_trylock_intent(&ck->c.lock));
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BUG_ON(!six_trylock_write(&ck->c.lock));
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return ck;
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}
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return NULL;
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}
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static struct bkey_cached *
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bkey_cached_reuse(struct btree_key_cache *c)
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{
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struct bucket_table *tbl;
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struct rhash_head *pos;
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struct bkey_cached *ck;
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unsigned i;
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mutex_lock(&c->lock);
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list_for_each_entry_reverse(ck, &c->freed, list)
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if (bkey_cached_lock_for_evict(ck)) {
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c->nr_freed--;
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list_del(&ck->list);
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mutex_unlock(&c->lock);
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return ck;
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}
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mutex_unlock(&c->lock);
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rcu_read_lock();
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tbl = rht_dereference_rcu(c->table.tbl, &c->table);
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for (i = 0; i < tbl->size; i++)
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rht_for_each_entry_rcu(ck, pos, tbl, i, hash) {
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if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags) &&
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bkey_cached_lock_for_evict(ck)) {
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bkey_cached_evict(c, ck);
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rcu_read_unlock();
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return ck;
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}
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}
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rcu_read_unlock();
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return NULL;
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}
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static struct bkey_cached *
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btree_key_cache_create(struct btree_key_cache *c,
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enum btree_id btree_id,
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struct bpos pos)
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{
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struct bkey_cached *ck;
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bool was_new = true;
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ck = bkey_cached_alloc(c);
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if (unlikely(!ck)) {
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ck = bkey_cached_reuse(c);
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if (unlikely(!ck))
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return ERR_PTR(-ENOMEM);
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was_new = false;
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}
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ck->c.level = 0;
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ck->c.btree_id = btree_id;
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ck->key.btree_id = btree_id;
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ck->key.pos = pos;
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ck->valid = false;
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ck->flags = 1U << BKEY_CACHED_ACCESSED;
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if (unlikely(rhashtable_lookup_insert_fast(&c->table,
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&ck->hash,
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bch2_btree_key_cache_params))) {
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/* We raced with another fill: */
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if (likely(was_new)) {
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six_unlock_write(&ck->c.lock);
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six_unlock_intent(&ck->c.lock);
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kfree(ck);
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} else {
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mutex_lock(&c->lock);
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bkey_cached_free(c, ck);
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mutex_unlock(&c->lock);
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}
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return NULL;
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}
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atomic_long_inc(&c->nr_keys);
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six_unlock_write(&ck->c.lock);
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return ck;
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}
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static int btree_key_cache_fill(struct btree_trans *trans,
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struct btree_iter *ck_iter,
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struct bkey_cached *ck)
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{
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struct btree_iter *iter;
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struct bkey_s_c k;
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unsigned new_u64s = 0;
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struct bkey_i *new_k = NULL;
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int ret;
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iter = bch2_trans_get_iter(trans, ck->key.btree_id,
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ck->key.pos, BTREE_ITER_SLOTS);
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k = bch2_btree_iter_peek_slot(iter);
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ret = bkey_err(k);
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if (ret)
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goto err;
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if (!bch2_btree_node_relock(ck_iter, 0)) {
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trace_transaction_restart_ip(trans->ip, _THIS_IP_);
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ret = -EINTR;
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goto err;
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}
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/*
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* bch2_varint_decode can read past the end of the buffer by at
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* most 7 bytes (it won't be used):
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*/
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new_u64s = k.k->u64s + 1;
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if (new_u64s > ck->u64s) {
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new_u64s = roundup_pow_of_two(new_u64s);
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new_k = kmalloc(new_u64s * sizeof(u64), GFP_NOFS);
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if (!new_k) {
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ret = -ENOMEM;
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goto err;
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}
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}
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bch2_btree_node_lock_write(ck_iter->l[0].b, ck_iter);
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if (new_k) {
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kfree(ck->k);
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ck->u64s = new_u64s;
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ck->k = new_k;
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}
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bkey_reassemble(ck->k, k);
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ck->valid = true;
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bch2_btree_node_unlock_write(ck_iter->l[0].b, ck_iter);
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/* We're not likely to need this iterator again: */
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set_btree_iter_dontneed(trans, iter);
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err:
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bch2_trans_iter_put(trans, iter);
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return ret;
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}
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static int bkey_cached_check_fn(struct six_lock *lock, void *p)
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{
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struct bkey_cached *ck = container_of(lock, struct bkey_cached, c.lock);
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const struct btree_iter *iter = p;
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return ck->key.btree_id == iter->btree_id &&
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!bpos_cmp(ck->key.pos, iter->pos) ? 0 : -1;
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}
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__flatten
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int bch2_btree_iter_traverse_cached(struct btree_iter *iter)
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{
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struct btree_trans *trans = iter->trans;
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struct bch_fs *c = trans->c;
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struct bkey_cached *ck;
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int ret = 0;
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BUG_ON(iter->level);
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if (btree_node_locked(iter, 0)) {
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ck = (void *) iter->l[0].b;
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goto fill;
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}
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retry:
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ck = bch2_btree_key_cache_find(c, iter->btree_id, iter->pos);
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if (!ck) {
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if (iter->flags & BTREE_ITER_CACHED_NOCREATE) {
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iter->l[0].b = NULL;
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return 0;
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}
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ck = btree_key_cache_create(&c->btree_key_cache,
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iter->btree_id, iter->pos);
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ret = PTR_ERR_OR_ZERO(ck);
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if (ret)
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goto err;
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if (!ck)
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goto retry;
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mark_btree_node_locked(iter, 0, SIX_LOCK_intent);
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iter->locks_want = 1;
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} else {
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enum six_lock_type lock_want = __btree_lock_want(iter, 0);
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if (!btree_node_lock((void *) ck, iter->pos, 0, iter, lock_want,
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bkey_cached_check_fn, iter, _THIS_IP_)) {
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if (ck->key.btree_id != iter->btree_id ||
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bpos_cmp(ck->key.pos, iter->pos)) {
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goto retry;
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}
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trace_transaction_restart_ip(trans->ip, _THIS_IP_);
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ret = -EINTR;
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goto err;
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}
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if (ck->key.btree_id != iter->btree_id ||
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bpos_cmp(ck->key.pos, iter->pos)) {
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six_unlock_type(&ck->c.lock, lock_want);
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goto retry;
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}
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mark_btree_node_locked(iter, 0, lock_want);
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}
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iter->l[0].lock_seq = ck->c.lock.state.seq;
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iter->l[0].b = (void *) ck;
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fill:
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if (!ck->valid && !(iter->flags & BTREE_ITER_CACHED_NOFILL)) {
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if (!btree_node_intent_locked(iter, 0))
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bch2_btree_iter_upgrade(iter, 1);
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if (!btree_node_intent_locked(iter, 0)) {
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trace_transaction_restart_ip(trans->ip, _THIS_IP_);
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ret = -EINTR;
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goto err;
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}
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ret = btree_key_cache_fill(trans, iter, ck);
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if (ret)
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goto err;
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}
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if (!test_bit(BKEY_CACHED_ACCESSED, &ck->flags))
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set_bit(BKEY_CACHED_ACCESSED, &ck->flags);
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iter->uptodate = BTREE_ITER_NEED_PEEK;
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if (!(iter->flags & BTREE_ITER_INTENT))
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bch2_btree_iter_downgrade(iter);
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else if (!iter->locks_want) {
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if (!__bch2_btree_iter_upgrade(iter, 1))
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ret = -EINTR;
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}
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return ret;
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err:
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if (ret != -EINTR) {
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btree_node_unlock(iter, 0);
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iter->flags |= BTREE_ITER_ERROR;
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iter->l[0].b = BTREE_ITER_NO_NODE_ERROR;
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}
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return ret;
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}
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static int btree_key_cache_flush_pos(struct btree_trans *trans,
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struct bkey_cached_key key,
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u64 journal_seq,
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unsigned commit_flags,
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bool evict)
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{
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struct bch_fs *c = trans->c;
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struct journal *j = &c->journal;
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struct btree_iter *c_iter = NULL, *b_iter = NULL;
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struct bkey_cached *ck = NULL;
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int ret;
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b_iter = bch2_trans_get_iter(trans, key.btree_id, key.pos,
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BTREE_ITER_SLOTS|
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BTREE_ITER_INTENT);
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c_iter = bch2_trans_get_iter(trans, key.btree_id, key.pos,
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BTREE_ITER_CACHED|
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BTREE_ITER_CACHED_NOFILL|
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BTREE_ITER_CACHED_NOCREATE|
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BTREE_ITER_INTENT);
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retry:
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ret = bch2_btree_iter_traverse(c_iter);
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if (ret)
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goto err;
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ck = (void *) c_iter->l[0].b;
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if (!ck ||
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(journal_seq && ck->journal.seq != journal_seq))
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goto out;
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if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
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if (!evict)
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goto out;
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goto evict;
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}
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/*
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* Since journal reclaim depends on us making progress here, and the
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* allocator/copygc depend on journal reclaim making progress, we need
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* to be using alloc reserves:
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* */
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ret = bch2_btree_iter_traverse(b_iter) ?:
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bch2_trans_update(trans, b_iter, ck->k, BTREE_TRIGGER_NORUN) ?:
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bch2_trans_commit(trans, NULL, NULL,
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BTREE_INSERT_NOUNLOCK|
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BTREE_INSERT_NOCHECK_RW|
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BTREE_INSERT_NOFAIL|
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BTREE_INSERT_USE_RESERVE|
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(ck->journal.seq == journal_last_seq(j)
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? BTREE_INSERT_JOURNAL_RESERVED
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: 0)|
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commit_flags);
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err:
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if (ret == -EINTR)
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goto retry;
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if (ret == -EAGAIN)
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goto out;
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if (ret) {
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bch2_fs_fatal_err_on(!bch2_journal_error(j), c,
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"error flushing key cache: %i", ret);
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goto out;
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}
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bch2_journal_pin_drop(j, &ck->journal);
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bch2_journal_preres_put(j, &ck->res);
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BUG_ON(!btree_node_locked(c_iter, 0));
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if (!evict) {
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if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
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clear_bit(BKEY_CACHED_DIRTY, &ck->flags);
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atomic_long_dec(&c->btree_key_cache.nr_dirty);
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}
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} else {
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evict:
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BUG_ON(!btree_node_intent_locked(c_iter, 0));
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mark_btree_node_unlocked(c_iter, 0);
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c_iter->l[0].b = NULL;
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six_lock_write(&ck->c.lock, NULL, NULL);
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if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
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clear_bit(BKEY_CACHED_DIRTY, &ck->flags);
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atomic_long_dec(&c->btree_key_cache.nr_dirty);
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}
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bkey_cached_evict(&c->btree_key_cache, ck);
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mutex_lock(&c->btree_key_cache.lock);
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bkey_cached_free(&c->btree_key_cache, ck);
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mutex_unlock(&c->btree_key_cache.lock);
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}
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out:
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bch2_trans_iter_put(trans, b_iter);
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bch2_trans_iter_put(trans, c_iter);
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return ret;
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}
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|
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int bch2_btree_key_cache_journal_flush(struct journal *j,
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struct journal_entry_pin *pin, u64 seq)
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{
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struct bch_fs *c = container_of(j, struct bch_fs, journal);
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struct bkey_cached *ck =
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container_of(pin, struct bkey_cached, journal);
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struct bkey_cached_key key;
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struct btree_trans trans;
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int ret = 0;
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int srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
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six_lock_read(&ck->c.lock, NULL, NULL);
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key = ck->key;
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if (ck->journal.seq != seq ||
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!test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
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six_unlock_read(&ck->c.lock);
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goto unlock;
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}
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six_unlock_read(&ck->c.lock);
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bch2_trans_init(&trans, c, 0, 0);
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ret = btree_key_cache_flush_pos(&trans, key, seq,
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BTREE_INSERT_JOURNAL_RECLAIM, false);
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bch2_trans_exit(&trans);
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unlock:
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srcu_read_unlock(&c->btree_trans_barrier, srcu_idx);
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return ret;
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}
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|
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/*
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* Flush and evict a key from the key cache:
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*/
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int bch2_btree_key_cache_flush(struct btree_trans *trans,
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enum btree_id id, struct bpos pos)
|
|
{
|
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struct bch_fs *c = trans->c;
|
|
struct bkey_cached_key key = { id, pos };
|
|
|
|
/* Fastpath - assume it won't be found: */
|
|
if (!bch2_btree_key_cache_find(c, id, pos))
|
|
return 0;
|
|
|
|
return btree_key_cache_flush_pos(trans, key, 0, 0, true);
|
|
}
|
|
|
|
bool bch2_btree_insert_key_cached(struct btree_trans *trans,
|
|
struct btree_iter *iter,
|
|
struct bkey_i *insert)
|
|
{
|
|
struct bch_fs *c = trans->c;
|
|
struct bkey_cached *ck = (void *) iter->l[0].b;
|
|
bool kick_reclaim = false;
|
|
|
|
BUG_ON(insert->u64s > ck->u64s);
|
|
|
|
if (likely(!(trans->flags & BTREE_INSERT_JOURNAL_REPLAY))) {
|
|
int difference;
|
|
|
|
BUG_ON(jset_u64s(insert->u64s) > trans->journal_preres.u64s);
|
|
|
|
difference = jset_u64s(insert->u64s) - ck->res.u64s;
|
|
if (difference > 0) {
|
|
trans->journal_preres.u64s -= difference;
|
|
ck->res.u64s += difference;
|
|
}
|
|
}
|
|
|
|
bkey_copy(ck->k, insert);
|
|
ck->valid = true;
|
|
|
|
if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
|
|
set_bit(BKEY_CACHED_DIRTY, &ck->flags);
|
|
atomic_long_inc(&c->btree_key_cache.nr_dirty);
|
|
|
|
if (bch2_nr_btree_keys_need_flush(c))
|
|
kick_reclaim = true;
|
|
}
|
|
|
|
bch2_journal_pin_update(&c->journal, trans->journal_res.seq,
|
|
&ck->journal, bch2_btree_key_cache_journal_flush);
|
|
|
|
if (kick_reclaim)
|
|
journal_reclaim_kick(&c->journal);
|
|
return true;
|
|
}
|
|
|
|
#ifdef CONFIG_BCACHEFS_DEBUG
|
|
void bch2_btree_key_cache_verify_clean(struct btree_trans *trans,
|
|
enum btree_id id, struct bpos pos)
|
|
{
|
|
BUG_ON(bch2_btree_key_cache_find(trans->c, id, pos));
|
|
}
|
|
#endif
|
|
|
|
static unsigned long bch2_btree_key_cache_scan(struct shrinker *shrink,
|
|
struct shrink_control *sc)
|
|
{
|
|
struct bch_fs *c = container_of(shrink, struct bch_fs,
|
|
btree_key_cache.shrink);
|
|
struct btree_key_cache *bc = &c->btree_key_cache;
|
|
struct bucket_table *tbl;
|
|
struct bkey_cached *ck, *t;
|
|
size_t scanned = 0, freed = 0, nr = sc->nr_to_scan;
|
|
unsigned start, flags;
|
|
int srcu_idx;
|
|
|
|
/* Return -1 if we can't do anything right now */
|
|
if (sc->gfp_mask & __GFP_FS)
|
|
mutex_lock(&bc->lock);
|
|
else if (!mutex_trylock(&bc->lock))
|
|
return -1;
|
|
|
|
srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
|
|
flags = memalloc_nofs_save();
|
|
|
|
/*
|
|
* Newest freed entries are at the end of the list - once we hit one
|
|
* that's too new to be freed, we can bail out:
|
|
*/
|
|
list_for_each_entry_safe(ck, t, &bc->freed, list) {
|
|
if (!poll_state_synchronize_srcu(&c->btree_trans_barrier,
|
|
ck->btree_trans_barrier_seq))
|
|
break;
|
|
|
|
list_del(&ck->list);
|
|
kmem_cache_free(bch2_key_cache, ck);
|
|
bc->nr_freed--;
|
|
scanned++;
|
|
freed++;
|
|
}
|
|
|
|
if (scanned >= nr)
|
|
goto out;
|
|
|
|
rcu_read_lock();
|
|
tbl = rht_dereference_rcu(bc->table.tbl, &bc->table);
|
|
if (bc->shrink_iter >= tbl->size)
|
|
bc->shrink_iter = 0;
|
|
start = bc->shrink_iter;
|
|
|
|
do {
|
|
struct rhash_head *pos, *next;
|
|
|
|
pos = rht_ptr_rcu(rht_bucket(tbl, bc->shrink_iter));
|
|
|
|
while (!rht_is_a_nulls(pos)) {
|
|
next = rht_dereference_bucket_rcu(pos->next, tbl, bc->shrink_iter);
|
|
ck = container_of(pos, struct bkey_cached, hash);
|
|
|
|
if (test_bit(BKEY_CACHED_DIRTY, &ck->flags))
|
|
goto next;
|
|
|
|
if (test_bit(BKEY_CACHED_ACCESSED, &ck->flags))
|
|
clear_bit(BKEY_CACHED_ACCESSED, &ck->flags);
|
|
else if (bkey_cached_lock_for_evict(ck)) {
|
|
bkey_cached_evict(bc, ck);
|
|
bkey_cached_free(bc, ck);
|
|
}
|
|
|
|
scanned++;
|
|
if (scanned >= nr)
|
|
break;
|
|
next:
|
|
pos = next;
|
|
}
|
|
|
|
bc->shrink_iter++;
|
|
if (bc->shrink_iter >= tbl->size)
|
|
bc->shrink_iter = 0;
|
|
} while (scanned < nr && bc->shrink_iter != start);
|
|
|
|
rcu_read_unlock();
|
|
out:
|
|
memalloc_nofs_restore(flags);
|
|
srcu_read_unlock(&c->btree_trans_barrier, srcu_idx);
|
|
mutex_unlock(&bc->lock);
|
|
|
|
return freed;
|
|
}
|
|
|
|
static unsigned long bch2_btree_key_cache_count(struct shrinker *shrink,
|
|
struct shrink_control *sc)
|
|
{
|
|
struct bch_fs *c = container_of(shrink, struct bch_fs,
|
|
btree_key_cache.shrink);
|
|
struct btree_key_cache *bc = &c->btree_key_cache;
|
|
long nr = atomic_long_read(&bc->nr_keys) -
|
|
atomic_long_read(&bc->nr_dirty);
|
|
|
|
return max(0L, nr);
|
|
}
|
|
|
|
void bch2_fs_btree_key_cache_exit(struct btree_key_cache *bc)
|
|
{
|
|
struct bch_fs *c = container_of(bc, struct bch_fs, btree_key_cache);
|
|
struct bucket_table *tbl;
|
|
struct bkey_cached *ck, *n;
|
|
struct rhash_head *pos;
|
|
unsigned i;
|
|
|
|
if (bc->shrink.list.next)
|
|
unregister_shrinker(&bc->shrink);
|
|
|
|
mutex_lock(&bc->lock);
|
|
|
|
rcu_read_lock();
|
|
tbl = rht_dereference_rcu(bc->table.tbl, &bc->table);
|
|
for (i = 0; i < tbl->size; i++)
|
|
rht_for_each_entry_rcu(ck, pos, tbl, i, hash) {
|
|
bkey_cached_evict(bc, ck);
|
|
list_add(&ck->list, &bc->freed);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
list_for_each_entry_safe(ck, n, &bc->freed, list) {
|
|
cond_resched();
|
|
|
|
bch2_journal_pin_drop(&c->journal, &ck->journal);
|
|
bch2_journal_preres_put(&c->journal, &ck->res);
|
|
|
|
list_del(&ck->list);
|
|
kfree(ck->k);
|
|
kmem_cache_free(bch2_key_cache, ck);
|
|
}
|
|
|
|
BUG_ON(atomic_long_read(&bc->nr_dirty) &&
|
|
!bch2_journal_error(&c->journal) &&
|
|
test_bit(BCH_FS_WAS_RW, &c->flags));
|
|
BUG_ON(atomic_long_read(&bc->nr_keys));
|
|
|
|
mutex_unlock(&bc->lock);
|
|
|
|
if (bc->table_init_done)
|
|
rhashtable_destroy(&bc->table);
|
|
}
|
|
|
|
void bch2_fs_btree_key_cache_init_early(struct btree_key_cache *c)
|
|
{
|
|
mutex_init(&c->lock);
|
|
INIT_LIST_HEAD(&c->freed);
|
|
}
|
|
|
|
int bch2_fs_btree_key_cache_init(struct btree_key_cache *bc)
|
|
{
|
|
struct bch_fs *c = container_of(bc, struct bch_fs, btree_key_cache);
|
|
int ret;
|
|
|
|
ret = rhashtable_init(&bc->table, &bch2_btree_key_cache_params);
|
|
if (ret)
|
|
return ret;
|
|
|
|
bc->table_init_done = true;
|
|
|
|
bc->shrink.seeks = 1;
|
|
bc->shrink.count_objects = bch2_btree_key_cache_count;
|
|
bc->shrink.scan_objects = bch2_btree_key_cache_scan;
|
|
return register_shrinker(&bc->shrink, "%s/btree_key_cache", c->name);
|
|
}
|
|
|
|
void bch2_btree_key_cache_to_text(struct printbuf *out, struct btree_key_cache *c)
|
|
{
|
|
pr_buf(out, "nr_freed:\t%zu\n", c->nr_freed);
|
|
pr_buf(out, "nr_keys:\t%zu\n", atomic_long_read(&c->nr_keys));
|
|
pr_buf(out, "nr_dirty:\t%zu\n", atomic_long_read(&c->nr_dirty));
|
|
}
|
|
|
|
void bch2_btree_key_cache_exit(void)
|
|
{
|
|
if (bch2_key_cache)
|
|
kmem_cache_destroy(bch2_key_cache);
|
|
}
|
|
|
|
int __init bch2_btree_key_cache_init(void)
|
|
{
|
|
bch2_key_cache = KMEM_CACHE(bkey_cached, 0);
|
|
if (!bch2_key_cache)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|