bch2_btree_key_cache_params));
memset(&ck->key, ~0, sizeof(ck->key));
- c->nr_keys--;
+ atomic_long_dec(&c->nr_keys);
}
static void bkey_cached_free(struct btree_key_cache *bc,
{
struct bkey_cached *ck;
- list_for_each_entry_reverse(ck, &c->freed, list)
- if (bkey_cached_lock_for_evict(ck)) {
- c->nr_freed--;
- return ck;
- }
-
ck = kmem_cache_alloc(bch2_key_cache, GFP_NOFS|__GFP_ZERO);
if (likely(ck)) {
INIT_LIST_HEAD(&ck->list);
return ck;
}
- list_for_each_entry(ck, &c->clean, list)
+ return NULL;
+}
+
+static struct bkey_cached *
+bkey_cached_reuse(struct btree_key_cache *c)
+{
+ struct bucket_table *tbl;
+ struct rhash_head *pos;
+ struct bkey_cached *ck;
+ unsigned i;
+
+ mutex_lock(&c->lock);
+ list_for_each_entry_reverse(ck, &c->freed, list)
if (bkey_cached_lock_for_evict(ck)) {
- bkey_cached_evict(c, ck);
+ c->nr_freed--;
+ list_del(&ck->list);
+ mutex_unlock(&c->lock);
return ck;
}
+ mutex_unlock(&c->lock);
+
+ rcu_read_lock();
+ tbl = rht_dereference_rcu(c->table.tbl, &c->table);
+ for (i = 0; i < tbl->size; i++)
+ rht_for_each_entry_rcu(ck, pos, tbl, i, hash) {
+ if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags) &&
+ bkey_cached_lock_for_evict(ck)) {
+ bkey_cached_evict(c, ck);
+ rcu_read_unlock();
+ return ck;
+ }
+ }
+ rcu_read_unlock();
return NULL;
}
struct bpos pos)
{
struct bkey_cached *ck;
+ bool was_new = true;
ck = bkey_cached_alloc(c);
- if (!ck)
- return ERR_PTR(-ENOMEM);
+
+ if (unlikely(!ck)) {
+ ck = bkey_cached_reuse(c);
+ if (unlikely(!ck))
+ return ERR_PTR(-ENOMEM);
+
+ was_new = false;
+ }
ck->c.level = 0;
ck->c.btree_id = btree_id;
ck->valid = false;
ck->flags = 1U << BKEY_CACHED_ACCESSED;
- if (rhashtable_lookup_insert_fast(&c->table,
+ if (unlikely(rhashtable_lookup_insert_fast(&c->table,
&ck->hash,
- bch2_btree_key_cache_params)) {
+ bch2_btree_key_cache_params))) {
/* We raced with another fill: */
- bkey_cached_free(c, ck);
+
+ if (likely(was_new)) {
+ six_unlock_write(&ck->c.lock);
+ six_unlock_intent(&ck->c.lock);
+ kfree(ck);
+ } else {
+ mutex_lock(&c->lock);
+ bkey_cached_free(c, ck);
+ mutex_unlock(&c->lock);
+ }
+
return NULL;
}
- c->nr_keys++;
+ atomic_long_inc(&c->nr_keys);
- list_move(&ck->list, &c->clean);
six_unlock_write(&ck->c.lock);
return ck;
return 0;
}
- mutex_lock(&c->btree_key_cache.lock);
ck = btree_key_cache_create(&c->btree_key_cache,
iter->btree_id, iter->pos);
- mutex_unlock(&c->btree_key_cache.lock);
-
ret = PTR_ERR_OR_ZERO(ck);
if (ret)
goto err;
bch2_journal_pin_drop(j, &ck->journal);
bch2_journal_preres_put(j, &ck->res);
+ BUG_ON(!btree_node_locked(c_iter, 0));
+
if (!evict) {
- mutex_lock(&c->btree_key_cache.lock);
if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
clear_bit(BKEY_CACHED_DIRTY, &ck->flags);
- c->btree_key_cache.nr_dirty--;
+ atomic_long_dec(&c->btree_key_cache.nr_dirty);
}
-
- list_move_tail(&ck->list, &c->btree_key_cache.clean);
- mutex_unlock(&c->btree_key_cache.lock);
} else {
evict:
BUG_ON(!btree_node_intent_locked(c_iter, 0));
six_lock_write(&ck->c.lock, NULL, NULL);
- mutex_lock(&c->btree_key_cache.lock);
if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
clear_bit(BKEY_CACHED_DIRTY, &ck->flags);
- c->btree_key_cache.nr_dirty--;
+ atomic_long_dec(&c->btree_key_cache.nr_dirty);
}
bkey_cached_evict(&c->btree_key_cache, ck);
+
+ mutex_lock(&c->btree_key_cache.lock);
bkey_cached_free(&c->btree_key_cache, ck);
mutex_unlock(&c->btree_key_cache.lock);
}
ck->valid = true;
if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
- mutex_lock(&c->btree_key_cache.lock);
- list_move(&ck->list, &c->btree_key_cache.dirty);
-
set_bit(BKEY_CACHED_DIRTY, &ck->flags);
- c->btree_key_cache.nr_dirty++;
+ atomic_long_inc(&c->btree_key_cache.nr_dirty);
if (bch2_nr_btree_keys_need_flush(c))
kick_reclaim = true;
-
- mutex_unlock(&c->btree_key_cache.lock);
}
bch2_journal_pin_update(&c->journal, trans->journal_res.seq,
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 flags;
+ unsigned start, flags;
+ int srcu_idx;
/* Return -1 if we can't do anything right now */
if (sc->gfp_mask & __GFP_FS)
else if (!mutex_trylock(&bc->lock))
return -1;
+ srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
flags = memalloc_nofs_save();
/*
if (scanned >= nr)
goto out;
- list_for_each_entry_safe(ck, t, &bc->clean, list) {
- 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);
- }
+ 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;
- scanned++;
- if (scanned >= nr) {
- if (&t->list != &bc->clean)
- list_move_tail(&bc->clean, &t->list);
- goto out;
+ 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;
btree_key_cache.shrink);
struct btree_key_cache *bc = &c->btree_key_cache;
- return bc->nr_keys;
+ return atomic_long_read(&bc->nr_keys);
}
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);
- list_splice(&bc->dirty, &bc->clean);
- list_for_each_entry_safe(ck, n, &bc->clean, list) {
+ 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);
- kfree(ck->k);
list_del(&ck->list);
+ kfree(ck->k);
kmem_cache_free(bch2_key_cache, ck);
- bc->nr_keys--;
}
- BUG_ON(bc->nr_dirty && !bch2_journal_error(&c->journal));
- BUG_ON(bc->nr_keys);
-
- list_for_each_entry_safe(ck, n, &bc->freed, list) {
- cond_resched();
+ BUG_ON(atomic_long_read(&bc->nr_dirty) && !bch2_journal_error(&c->journal));
+ BUG_ON(atomic_long_read(&bc->nr_keys));
- list_del(&ck->list);
- kmem_cache_free(bch2_key_cache, ck);
- }
mutex_unlock(&bc->lock);
if (bc->table_init_done)
{
mutex_init(&c->lock);
INIT_LIST_HEAD(&c->freed);
- INIT_LIST_HEAD(&c->clean);
- INIT_LIST_HEAD(&c->dirty);
}
int bch2_fs_btree_key_cache_init(struct btree_key_cache *bc)
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", c->nr_keys);
- pr_buf(out, "nr_dirty:\t%zu\n", c->nr_dirty);
+ 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)
projects / linux.git / commitdiff