+// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "btree_cache.h"
#include "btree_key_cache.h"
#include "btree_locking.h"
#include "btree_update.h"
+#include "errcode.h"
#include "error.h"
#include "journal.h"
#include "journal_reclaim.h"
#include <linux/sched/mm.h>
#include <trace/events/bcachefs.h>
+static inline bool btree_uses_pcpu_readers(enum btree_id id)
+{
+ return id == BTREE_ID_subvolumes;
+}
+
static struct kmem_cache *bch2_key_cache;
static int bch2_btree_key_cache_cmp_fn(struct rhashtable_compare_arg *arg,
ck->btree_trans_barrier_seq =
start_poll_synchronize_srcu(&c->btree_trans_barrier);
- list_move_tail(&ck->list, &bc->freed);
- bc->nr_freed++;
+ if (ck->c.lock.readers)
+ list_move_tail(&ck->list, &bc->freed_pcpu);
+ else
+ list_move_tail(&ck->list, &bc->freed_nonpcpu);
+ atomic_long_inc(&bc->nr_freed);
+
+ kfree(ck->k);
+ ck->k = NULL;
+ ck->u64s = 0;
+
+ six_unlock_write(&ck->c.lock);
+ six_unlock_intent(&ck->c.lock);
+}
+
+static void __bkey_cached_move_to_freelist_ordered(struct btree_key_cache *bc,
+ struct bkey_cached *ck)
+{
+ struct bkey_cached *pos;
+
+ list_for_each_entry_reverse(pos, &bc->freed_nonpcpu, list) {
+ if (ULONG_CMP_GE(ck->btree_trans_barrier_seq,
+ pos->btree_trans_barrier_seq)) {
+ list_move(&ck->list, &pos->list);
+ return;
+ }
+ }
+
+ list_move(&ck->list, &bc->freed_nonpcpu);
+}
+
+static void bkey_cached_move_to_freelist(struct btree_key_cache *bc,
+ struct bkey_cached *ck)
+{
+ struct btree_key_cache_freelist *f;
+ bool freed = false;
+
+ BUG_ON(test_bit(BKEY_CACHED_DIRTY, &ck->flags));
+
+ if (!ck->c.lock.readers) {
+#ifdef __KERNEL__
+ preempt_disable();
+ f = this_cpu_ptr(bc->pcpu_freed);
+
+ if (f->nr < ARRAY_SIZE(f->objs)) {
+ f->objs[f->nr++] = ck;
+ freed = true;
+ }
+ preempt_enable();
+
+ if (!freed) {
+ mutex_lock(&bc->lock);
+ preempt_disable();
+ f = this_cpu_ptr(bc->pcpu_freed);
+
+ while (f->nr > ARRAY_SIZE(f->objs) / 2) {
+ struct bkey_cached *ck2 = f->objs[--f->nr];
+
+ __bkey_cached_move_to_freelist_ordered(bc, ck2);
+ }
+ preempt_enable();
+
+ __bkey_cached_move_to_freelist_ordered(bc, ck);
+ mutex_unlock(&bc->lock);
+ }
+#else
+ mutex_lock(&bc->lock);
+ list_move_tail(&ck->list, &bc->freed_nonpcpu);
+ mutex_unlock(&bc->lock);
+#endif
+ } else {
+ mutex_lock(&bc->lock);
+ list_move_tail(&ck->list, &bc->freed_pcpu);
+ mutex_unlock(&bc->lock);
+ }
+}
+
+static void bkey_cached_free_fast(struct btree_key_cache *bc,
+ struct bkey_cached *ck)
+{
+ struct bch_fs *c = container_of(bc, struct bch_fs, btree_key_cache);
+
+ ck->btree_trans_barrier_seq =
+ start_poll_synchronize_srcu(&c->btree_trans_barrier);
+
+ list_del_init(&ck->list);
+ atomic_long_inc(&bc->nr_freed);
kfree(ck->k);
ck->k = NULL;
ck->u64s = 0;
+ bkey_cached_move_to_freelist(bc, ck);
+
six_unlock_write(&ck->c.lock);
six_unlock_intent(&ck->c.lock);
}
static struct bkey_cached *
-bkey_cached_alloc(struct btree_key_cache *c)
+bkey_cached_alloc(struct btree_trans *trans, struct btree_path *path)
{
- struct bkey_cached *ck;
+ struct bch_fs *c = trans->c;
+ struct btree_key_cache *bc = &c->btree_key_cache;
+ struct bkey_cached *ck = NULL;
+ struct btree_key_cache_freelist *f;
+ bool pcpu_readers = btree_uses_pcpu_readers(path->btree_id);
+
+ if (!pcpu_readers) {
+#ifdef __KERNEL__
+ preempt_disable();
+ f = this_cpu_ptr(bc->pcpu_freed);
+ if (f->nr)
+ ck = f->objs[--f->nr];
+ preempt_enable();
+
+ if (!ck) {
+ mutex_lock(&bc->lock);
+ preempt_disable();
+ f = this_cpu_ptr(bc->pcpu_freed);
+
+ while (!list_empty(&bc->freed_nonpcpu) &&
+ f->nr < ARRAY_SIZE(f->objs) / 2) {
+ ck = list_last_entry(&bc->freed_nonpcpu, struct bkey_cached, list);
+ list_del_init(&ck->list);
+ f->objs[f->nr++] = ck;
+ }
+ ck = f->nr ? f->objs[--f->nr] : NULL;
+ preempt_enable();
+ mutex_unlock(&bc->lock);
+ }
+#else
+ mutex_lock(&bc->lock);
+ if (!list_empty(&bc->freed_nonpcpu)) {
+ ck = list_last_entry(&bc->freed_nonpcpu, struct bkey_cached, list);
+ list_del_init(&ck->list);
+ }
+ mutex_unlock(&bc->lock);
+#endif
+ } else {
+ mutex_lock(&bc->lock);
+ if (!list_empty(&bc->freed_pcpu)) {
+ ck = list_last_entry(&bc->freed_pcpu, struct bkey_cached, list);
+ list_del_init(&ck->list);
+ }
+ mutex_unlock(&bc->lock);
+ }
+
+ if (ck) {
+ int ret;
+
+ ret = btree_node_lock_nopath(trans, &ck->c, SIX_LOCK_intent);
+ if (unlikely(ret)) {
+ bkey_cached_move_to_freelist(bc, ck);
+ return ERR_PTR(ret);
+ }
+
+ path->l[0].b = (void *) ck;
+ path->l[0].lock_seq = ck->c.lock.state.seq;
+ mark_btree_node_locked(trans, path, 0, SIX_LOCK_intent);
+
+ ret = bch2_btree_node_lock_write(trans, path, &ck->c);
+ if (unlikely(ret)) {
+ btree_node_unlock(trans, path, 0);
+ bkey_cached_move_to_freelist(bc, ck);
+ return ERR_PTR(ret);
+ }
+
+ return ck;
+ }
+
+ /* GFP_NOFS because we're holding btree locks: */
ck = kmem_cache_alloc(bch2_key_cache, GFP_NOFS|__GFP_ZERO);
if (likely(ck)) {
INIT_LIST_HEAD(&ck->list);
- six_lock_init(&ck->c.lock);
+ __six_lock_init(&ck->c.lock, "b->c.lock", &bch2_btree_node_lock_key);
+ if (pcpu_readers)
+ six_lock_pcpu_alloc(&ck->c.lock);
+
+ ck->c.cached = true;
BUG_ON(!six_trylock_intent(&ck->c.lock));
BUG_ON(!six_trylock_write(&ck->c.lock));
return ck;
unsigned i;
mutex_lock(&c->lock);
- list_for_each_entry_reverse(ck, &c->freed, list)
- if (bkey_cached_lock_for_evict(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++)
if (!test_bit(BKEY_CACHED_DIRTY, &ck->flags) &&
bkey_cached_lock_for_evict(ck)) {
bkey_cached_evict(c, ck);
- rcu_read_unlock();
- return ck;
+ goto out;
}
}
+ ck = NULL;
+out:
rcu_read_unlock();
-
- return NULL;
+ mutex_unlock(&c->lock);
+ return ck;
}
static struct bkey_cached *
-btree_key_cache_create(struct bch_fs *c,
- enum btree_id btree_id,
- struct bpos pos)
+btree_key_cache_create(struct btree_trans *trans, struct btree_path *path)
{
+ struct bch_fs *c = trans->c;
struct btree_key_cache *bc = &c->btree_key_cache;
struct bkey_cached *ck;
bool was_new = true;
- ck = bkey_cached_alloc(bc);
+ ck = bkey_cached_alloc(trans, path);
+ if (IS_ERR(ck))
+ return ck;
if (unlikely(!ck)) {
ck = bkey_cached_reuse(bc);
if (unlikely(!ck)) {
bch_err(c, "error allocating memory for key cache item, btree %s",
- bch2_btree_ids[btree_id]);
+ bch2_btree_ids[path->btree_id]);
return ERR_PTR(-ENOMEM);
}
+ mark_btree_node_locked(trans, path, 0, SIX_LOCK_intent);
was_new = false;
+ } else {
+ if (path->btree_id == BTREE_ID_subvolumes)
+ six_lock_pcpu_alloc(&ck->c.lock);
}
- if (btree_id == BTREE_ID_subvolumes)
- six_lock_pcpu_alloc(&ck->c.lock);
- else
- six_lock_pcpu_free(&ck->c.lock);
-
ck->c.level = 0;
- ck->c.btree_id = btree_id;
- ck->key.btree_id = btree_id;
- ck->key.pos = pos;
+ ck->c.btree_id = path->btree_id;
+ ck->key.btree_id = path->btree_id;
+ ck->key.pos = path->pos;
ck->valid = false;
ck->flags = 1U << BKEY_CACHED_ACCESSED;
if (likely(was_new)) {
six_unlock_write(&ck->c.lock);
six_unlock_intent(&ck->c.lock);
+ mark_btree_node_locked(trans, path, 0, BTREE_NODE_UNLOCKED);
kfree(ck);
} else {
- mutex_lock(&bc->lock);
- bkey_cached_free(bc, ck);
- mutex_unlock(&bc->lock);
+ bkey_cached_free_fast(bc, ck);
}
return NULL;
k = bch2_btree_path_peek_slot(path, &u);
if (!bch2_btree_node_relock(trans, ck_path, 0)) {
- trace_trans_restart_relock_key_cache_fill(trans->fn,
- _THIS_IP_, ck_path->btree_id, &ck_path->pos);
- ret = btree_trans_restart(trans);
+ trace_and_count(trans->c, trans_restart_relock_key_cache_fill, trans, _THIS_IP_, ck_path);
+ ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_key_cache_raced);
goto err;
}
*/
new_u64s = k.k->u64s + 1;
+ /*
+ * Allocate some extra space so that the transaction commit path is less
+ * likely to have to reallocate, since that requires a transaction
+ * restart:
+ */
+ new_u64s = min(256U, (new_u64s * 3) / 2);
+
if (new_u64s > ck->u64s) {
new_u64s = roundup_pow_of_two(new_u64s);
new_k = kmalloc(new_u64s * sizeof(u64), GFP_NOFS);
}
}
- /*
- * XXX: not allowed to be holding read locks when we take a write lock,
- * currently
- */
- bch2_btree_node_lock_write(trans, ck_path, ck_path->l[0].b);
+ ret = bch2_btree_node_lock_write(trans, ck_path, &ck_path->l[0].b->c);
+ if (ret) {
+ kfree(new_k);
+ goto err;
+ }
+
if (new_k) {
kfree(ck->k);
ck->u64s = new_u64s;
return ret;
}
-static int bkey_cached_check_fn(struct six_lock *lock, void *p)
-{
- struct bkey_cached *ck = container_of(lock, struct bkey_cached, c.lock);
- const struct btree_path *path = p;
-
- return ck->key.btree_id == path->btree_id &&
- !bpos_cmp(ck->key.pos, path->pos) ? 0 : -1;
-}
-
-__flatten
-int bch2_btree_path_traverse_cached(struct btree_trans *trans, struct btree_path *path,
- unsigned flags)
+static noinline int
+bch2_btree_path_traverse_cached_slowpath(struct btree_trans *trans, struct btree_path *path,
+ unsigned flags)
{
struct bch_fs *c = trans->c;
struct bkey_cached *ck;
retry:
ck = bch2_btree_key_cache_find(c, path->btree_id, path->pos);
if (!ck) {
- if (flags & BTREE_ITER_CACHED_NOCREATE) {
- path->l[0].b = NULL;
- return 0;
- }
-
- ck = btree_key_cache_create(c, path->btree_id, path->pos);
+ ck = btree_key_cache_create(trans, path);
ret = PTR_ERR_OR_ZERO(ck);
if (ret)
goto err;
if (!ck)
goto retry;
- mark_btree_node_locked(path, 0, SIX_LOCK_intent);
+ mark_btree_node_locked(trans, path, 0, SIX_LOCK_intent);
path->locks_want = 1;
} else {
enum six_lock_type lock_want = __btree_lock_want(path, 0);
- if (!btree_node_lock(trans, path, (void *) ck, path->pos, 0,
- lock_want,
- bkey_cached_check_fn, path, _THIS_IP_)) {
- if (!trans->restarted)
- goto retry;
-
- ret = -EINTR;
+ ret = btree_node_lock(trans, path, (void *) ck, 0,
+ lock_want, _THIS_IP_);
+ if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
goto err;
- }
+
+ BUG_ON(ret);
if (ck->key.btree_id != path->btree_id ||
bpos_cmp(ck->key.pos, path->pos)) {
goto retry;
}
- mark_btree_node_locked(path, 0, lock_want);
+ mark_btree_node_locked(trans, path, 0, lock_want);
}
path->l[0].lock_seq = ck->c.lock.state.seq;
path->l[0].b = (void *) ck;
fill:
- if (!ck->valid && !(flags & BTREE_ITER_CACHED_NOFILL)) {
+ if (!ck->valid) {
+ /*
+ * Using the underscore version because we haven't set
+ * path->uptodate yet:
+ */
if (!path->locks_want &&
!__bch2_btree_path_upgrade(trans, path, 1)) {
- trace_transaction_restart_ip(trans->fn, _THIS_IP_);
- ret = btree_trans_restart(trans);
+ trace_and_count(trans->c, trans_restart_key_cache_upgrade, trans, _THIS_IP_);
+ ret = btree_trans_restart(trans, BCH_ERR_transaction_restart_key_cache_upgrade);
goto err;
}
set_bit(BKEY_CACHED_ACCESSED, &ck->flags);
path->uptodate = BTREE_ITER_UPTODATE;
+ BUG_ON(!ck->valid);
BUG_ON(btree_node_locked_type(path, 0) != btree_lock_want(path, 0));
return ret;
err:
- if (ret != -EINTR) {
- btree_node_unlock(path, 0);
- path->l[0].b = BTREE_ITER_NO_NODE_ERROR;
+ if (!bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
+ btree_node_unlock(trans, path, 0);
+ path->l[0].b = ERR_PTR(ret);
}
return ret;
}
+int bch2_btree_path_traverse_cached(struct btree_trans *trans, struct btree_path *path,
+ unsigned flags)
+{
+ struct bch_fs *c = trans->c;
+ struct bkey_cached *ck;
+ int ret = 0;
+
+ EBUG_ON(path->level);
+
+ path->l[1].b = NULL;
+
+ if (bch2_btree_node_relock(trans, path, 0)) {
+ ck = (void *) path->l[0].b;
+ goto fill;
+ }
+retry:
+ ck = bch2_btree_key_cache_find(c, path->btree_id, path->pos);
+ if (!ck) {
+ return bch2_btree_path_traverse_cached_slowpath(trans, path, flags);
+ } else {
+ enum six_lock_type lock_want = __btree_lock_want(path, 0);
+
+ ret = btree_node_lock(trans, path, (void *) ck, 0,
+ lock_want, _THIS_IP_);
+ EBUG_ON(ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart));
+
+ if (ret)
+ return ret;
+
+ if (ck->key.btree_id != path->btree_id ||
+ bpos_cmp(ck->key.pos, path->pos)) {
+ six_unlock_type(&ck->c.lock, lock_want);
+ goto retry;
+ }
+
+ mark_btree_node_locked(trans, path, 0, lock_want);
+ }
+
+ path->l[0].lock_seq = ck->c.lock.state.seq;
+ path->l[0].b = (void *) ck;
+fill:
+ if (!ck->valid)
+ return bch2_btree_path_traverse_cached_slowpath(trans, path, flags);
+
+ if (!test_bit(BKEY_CACHED_ACCESSED, &ck->flags))
+ set_bit(BKEY_CACHED_ACCESSED, &ck->flags);
+
+ path->uptodate = BTREE_ITER_UPTODATE;
+ EBUG_ON(!ck->valid);
+ EBUG_ON(btree_node_locked_type(path, 0) != btree_lock_want(path, 0));
+
+ return ret;
+}
+
static int btree_key_cache_flush_pos(struct btree_trans *trans,
struct bkey_cached_key key,
u64 journal_seq,
BTREE_ITER_ALL_SNAPSHOTS);
bch2_trans_iter_init(trans, &c_iter, key.btree_id, key.pos,
BTREE_ITER_CACHED|
- BTREE_ITER_CACHED_NOFILL|
- BTREE_ITER_CACHED_NOCREATE|
BTREE_ITER_INTENT);
b_iter.flags &= ~BTREE_ITER_WITH_KEY_CACHE;
* Since journal reclaim depends on us making progress here, and the
* allocator/copygc depend on journal reclaim making progress, we need
* to be using alloc reserves:
- * */
+ */
ret = bch2_btree_iter_traverse(&b_iter) ?:
bch2_trans_update(trans, &b_iter, ck->k,
BTREE_UPDATE_KEY_CACHE_RECLAIM|
BTREE_INSERT_NOFAIL|
BTREE_INSERT_USE_RESERVE|
(ck->journal.seq == journal_last_seq(j)
- ? BTREE_INSERT_JOURNAL_RESERVED
+ ? JOURNAL_WATERMARK_reserved
: 0)|
commit_flags);
- if (ret) {
- bch2_fs_fatal_err_on(ret != -EINTR &&
- ret != -EAGAIN &&
- !bch2_journal_error(j), c,
- "error flushing key cache: %i", ret);
+
+ bch2_fs_fatal_err_on(ret &&
+ !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
+ !bch2_err_matches(ret, BCH_ERR_journal_reclaim_would_deadlock) &&
+ !bch2_journal_error(j), c,
+ "error flushing key cache: %s", bch2_err_str(ret));
+ if (ret)
goto out;
- }
bch2_journal_pin_drop(j, &ck->journal);
bch2_journal_preres_put(j, &ck->res);
atomic_long_dec(&c->btree_key_cache.nr_dirty);
}
} else {
+ struct btree_path *path2;
evict:
- BUG_ON(!btree_node_intent_locked(c_iter.path, 0));
+ trans_for_each_path(trans, path2)
+ if (path2 != c_iter.path)
+ __bch2_btree_path_unlock(trans, path2);
- mark_btree_node_unlocked(c_iter.path, 0);
- c_iter.path->l[0].b = NULL;
-
- six_lock_write(&ck->c.lock, NULL, NULL);
+ bch2_btree_node_lock_write_nofail(trans, c_iter.path, &ck->c);
if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
clear_bit(BKEY_CACHED_DIRTY, &ck->flags);
atomic_long_dec(&c->btree_key_cache.nr_dirty);
}
+ mark_btree_node_locked_noreset(c_iter.path, 0, BTREE_NODE_UNLOCKED);
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);
+ bkey_cached_free_fast(&c->btree_key_cache, ck);
}
out:
bch2_trans_iter_exit(trans, &b_iter);
struct bkey_cached *ck =
container_of(pin, struct bkey_cached, journal);
struct bkey_cached_key key;
+ struct btree_trans trans;
+ int srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
int ret = 0;
- int srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
+ bch2_trans_init(&trans, c, 0, 0);
- six_lock_read(&ck->c.lock, NULL, NULL);
+ btree_node_lock_nopath_nofail(&trans, &ck->c, SIX_LOCK_read);
key = ck->key;
if (ck->journal.seq != seq ||
}
six_unlock_read(&ck->c.lock);
- ret = bch2_trans_do(c, NULL, NULL, 0,
+ ret = commit_do(&trans, NULL, NULL, 0,
btree_key_cache_flush_pos(&trans, key, seq,
BTREE_INSERT_JOURNAL_RECLAIM, false));
unlock:
srcu_read_unlock(&c->btree_trans_barrier, srcu_idx);
+ bch2_trans_exit(&trans);
return ret;
}
return true;
}
-#ifdef CONFIG_BCACHEFS_DEBUG
-void bch2_btree_key_cache_verify_clean(struct btree_trans *trans,
- enum btree_id id, struct bpos pos)
+void bch2_btree_key_cache_drop(struct btree_trans *trans,
+ struct btree_path *path)
{
- BUG_ON(bch2_btree_key_cache_find(trans->c, id, pos));
+ struct bch_fs *c = trans->c;
+ struct bkey_cached *ck = (void *) path->l[0].b;
+
+ BUG_ON(!ck->valid);
+
+ /*
+ * We just did an update to the btree, bypassing the key cache: the key
+ * cache key is now stale and must be dropped, even if dirty:
+ */
+ if (test_bit(BKEY_CACHED_DIRTY, &ck->flags)) {
+ clear_bit(BKEY_CACHED_DIRTY, &ck->flags);
+ atomic_long_dec(&c->btree_key_cache.nr_dirty);
+ bch2_journal_pin_drop(&c->journal, &ck->journal);
+ }
+
+ ck->valid = false;
}
-#endif
static unsigned long bch2_btree_key_cache_scan(struct shrinker *shrink,
struct shrink_control *sc)
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;
-
+ mutex_lock(&bc->lock);
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) {
+ list_for_each_entry_safe(ck, t, &bc->freed_nonpcpu, list) {
if (!poll_state_synchronize_srcu(&c->btree_trans_barrier,
ck->btree_trans_barrier_seq))
break;
list_del(&ck->list);
+ six_lock_pcpu_free(&ck->c.lock);
kmem_cache_free(bch2_key_cache, ck);
- bc->nr_freed--;
+ atomic_long_dec(&bc->nr_freed);
+ scanned++;
+ freed++;
+ }
+
+ if (scanned >= nr)
+ goto out;
+
+ list_for_each_entry_safe(ck, t, &bc->freed_pcpu, list) {
+ if (!poll_state_synchronize_srcu(&c->btree_trans_barrier,
+ ck->btree_trans_barrier_seq))
+ break;
+
+ list_del(&ck->list);
+ six_lock_pcpu_free(&ck->c.lock);
+ kmem_cache_free(bch2_key_cache, ck);
+ atomic_long_dec(&bc->nr_freed);
scanned++;
freed++;
}
struct bkey_cached *ck, *n;
struct rhash_head *pos;
unsigned i;
+#ifdef __KERNEL__
+ int cpu;
+#endif
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);
- if (tbl)
- 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();
+ /*
+ * The loop is needed to guard against racing with rehash:
+ */
+ while (atomic_long_read(&bc->nr_keys)) {
+ rcu_read_lock();
+ tbl = rht_dereference_rcu(bc->table.tbl, &bc->table);
+ if (tbl)
+ 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_nonpcpu);
+ }
+ rcu_read_unlock();
+ }
+
+#ifdef __KERNEL__
+ for_each_possible_cpu(cpu) {
+ struct btree_key_cache_freelist *f =
+ per_cpu_ptr(bc->pcpu_freed, cpu);
- list_for_each_entry_safe(ck, n, &bc->freed, list) {
+ for (i = 0; i < f->nr; i++) {
+ ck = f->objs[i];
+ list_add(&ck->list, &bc->freed_nonpcpu);
+ }
+ }
+#endif
+
+ list_splice(&bc->freed_pcpu, &bc->freed_nonpcpu);
+
+ list_for_each_entry_safe(ck, n, &bc->freed_nonpcpu, list) {
cond_resched();
bch2_journal_pin_drop(&c->journal, &ck->journal);
list_del(&ck->list);
kfree(ck->k);
+ six_lock_pcpu_free(&ck->c.lock);
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));
+ if (atomic_long_read(&bc->nr_dirty) &&
+ !bch2_journal_error(&c->journal) &&
+ test_bit(BCH_FS_WAS_RW, &c->flags))
+ panic("btree key cache shutdown error: nr_dirty nonzero (%li)\n",
+ atomic_long_read(&bc->nr_dirty));
+
+ if (atomic_long_read(&bc->nr_keys))
+ panic("btree key cache shutdown error: nr_keys nonzero (%li)\n",
+ atomic_long_read(&bc->nr_keys));
mutex_unlock(&bc->lock);
if (bc->table_init_done)
rhashtable_destroy(&bc->table);
+
+ free_percpu(bc->pcpu_freed);
}
void bch2_fs_btree_key_cache_init_early(struct btree_key_cache *c)
{
mutex_init(&c->lock);
- INIT_LIST_HEAD(&c->freed);
+ INIT_LIST_HEAD(&c->freed_pcpu);
+ INIT_LIST_HEAD(&c->freed_nonpcpu);
}
-int bch2_fs_btree_key_cache_init(struct btree_key_cache *c)
+static void bch2_btree_key_cache_shrinker_to_text(struct printbuf *out, struct shrinker *shrink)
{
+ struct btree_key_cache *bc =
+ container_of(shrink, struct btree_key_cache, shrink);
+
+ bch2_btree_key_cache_to_text(out, bc);
+}
+
+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(&c->table, &bch2_btree_key_cache_params);
+#ifdef __KERNEL__
+ bc->pcpu_freed = alloc_percpu(struct btree_key_cache_freelist);
+ if (!bc->pcpu_freed)
+ return -ENOMEM;
+#endif
+
+ ret = rhashtable_init(&bc->table, &bch2_btree_key_cache_params);
if (ret)
return ret;
- c->table_init_done = true;
+ bc->table_init_done = true;
- c->shrink.seeks = 1;
- c->shrink.count_objects = bch2_btree_key_cache_count;
- c->shrink.scan_objects = bch2_btree_key_cache_scan;
- return register_shrinker(&c->shrink);
+ bc->shrink.seeks = 0;
+ bc->shrink.count_objects = bch2_btree_key_cache_count;
+ bc->shrink.scan_objects = bch2_btree_key_cache_scan;
+ bc->shrink.to_text = bch2_btree_key_cache_shrinker_to_text;
+ 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));
+ prt_printf(out, "nr_freed:\t%zu", atomic_long_read(&c->nr_freed));
+ prt_newline(out);
+ prt_printf(out, "nr_keys:\t%lu", atomic_long_read(&c->nr_keys));
+ prt_newline(out);
+ prt_printf(out, "nr_dirty:\t%lu", atomic_long_read(&c->nr_dirty));
+ prt_newline(out);
}
void bch2_btree_key_cache_exit(void)
{
- if (bch2_key_cache)
- kmem_cache_destroy(bch2_key_cache);
+ kmem_cache_destroy(bch2_key_cache);
}
int __init bch2_btree_key_cache_init(void)
projects / bcachefs-tools-debian / blobdiff