// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
+#include "bkey_buf.h"
#include "btree_cache.h"
#include "btree_io.h"
#include "btree_iter.h"
#include "btree_locking.h"
#include "debug.h"
+#include "error.h"
#include <linux/prefetch.h>
#include <linux/sched/mm.h>
#include <trace/events/bcachefs.h>
-const char * const bch2_btree_ids[] = {
-#define x(kwd, val, name) name,
- BCH_BTREE_IDS()
-#undef x
- NULL
-};
+struct lock_class_key bch2_btree_node_lock_key;
void bch2_recalc_btree_reserve(struct bch_fs *c)
{
for (i = 0; i < BTREE_ID_NR; i++)
if (c->btree_roots[i].b)
reserve += min_t(unsigned, 1,
- c->btree_roots[i].b->level) * 8;
+ c->btree_roots[i].b->c.level) * 8;
c->btree_cache.reserve = reserve;
}
return max_t(int, 0, bc->used - bc->reserve);
}
-static void __btree_node_data_free(struct bch_fs *c, struct btree *b)
+static void btree_node_data_free(struct bch_fs *c, struct btree *b)
{
+ struct btree_cache *bc = &c->btree_cache;
+
EBUG_ON(btree_node_write_in_flight(b));
kvpfree(b->data, btree_bytes(c));
b->data = NULL;
- bch2_btree_keys_free(b);
-}
-
-static void btree_node_data_free(struct bch_fs *c, struct btree *b)
-{
- struct btree_cache *bc = &c->btree_cache;
+#ifdef __KERNEL__
+ vfree(b->aux_data);
+#else
+ munmap(b->aux_data, btree_aux_data_bytes(b));
+#endif
+ b->aux_data = NULL;
- __btree_node_data_free(c, b);
bc->used--;
list_move(&b->list, &bc->freed);
}
.obj_cmpfn = bch2_btree_cache_cmp_fn,
};
-static void btree_node_data_alloc(struct bch_fs *c, struct btree *b, gfp_t gfp)
+static int btree_node_data_alloc(struct bch_fs *c, struct btree *b, gfp_t gfp)
{
- struct btree_cache *bc = &c->btree_cache;
+ BUG_ON(b->data || b->aux_data);
b->data = kvpmalloc(btree_bytes(c), gfp);
if (!b->data)
- goto err;
-
- if (bch2_btree_keys_alloc(b, btree_page_order(c), gfp))
- goto err;
+ return -ENOMEM;
+#ifdef __KERNEL__
+ b->aux_data = vmalloc_exec(btree_aux_data_bytes(b), gfp);
+#else
+ b->aux_data = mmap(NULL, btree_aux_data_bytes(b),
+ PROT_READ|PROT_WRITE|PROT_EXEC,
+ MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
+#endif
+ if (!b->aux_data) {
+ kvpfree(b->data, btree_bytes(c));
+ b->data = NULL;
+ return -ENOMEM;
+ }
- bc->used++;
- list_move(&b->list, &bc->freeable);
- return;
-err:
- kvpfree(b->data, btree_bytes(c));
- b->data = NULL;
- list_move(&b->list, &bc->freed);
+ return 0;
}
-static struct btree *btree_node_mem_alloc(struct bch_fs *c, gfp_t gfp)
+static struct btree *__btree_node_mem_alloc(struct bch_fs *c)
{
- struct btree *b = kzalloc(sizeof(struct btree), gfp);
+ struct btree *b = kzalloc(sizeof(struct btree), GFP_KERNEL);
if (!b)
return NULL;
bkey_btree_ptr_init(&b->key);
- six_lock_init(&b->lock);
+ __six_lock_init(&b->c.lock, "b->c.lock", &bch2_btree_node_lock_key);
INIT_LIST_HEAD(&b->list);
INIT_LIST_HEAD(&b->write_blocked);
+ b->byte_order = ilog2(btree_bytes(c));
+ return b;
+}
- btree_node_data_alloc(c, b, gfp);
- return b->data ? b : NULL;
+struct btree *__bch2_btree_node_mem_alloc(struct bch_fs *c)
+{
+ struct btree_cache *bc = &c->btree_cache;
+ struct btree *b = __btree_node_mem_alloc(c);
+ if (!b)
+ return NULL;
+
+ if (btree_node_data_alloc(c, b, GFP_KERNEL)) {
+ kfree(b);
+ return NULL;
+ }
+
+ bc->used++;
+ list_add(&b->list, &bc->freeable);
+ return b;
}
/* Btree in memory cache - hash table */
/* Cause future lookups for this node to fail: */
b->hash_val = 0;
+
+ six_lock_wakeup_all(&b->c.lock);
}
int __bch2_btree_node_hash_insert(struct btree_cache *bc, struct btree *b)
{
int ret;
- b->level = level;
- b->btree_id = id;
+ b->c.level = level;
+ b->c.btree_id = id;
+
+ if (level)
+ six_lock_pcpu_alloc(&b->c.lock);
+ else
+ six_lock_pcpu_free_rcu(&b->c.lock);
mutex_lock(&bc->lock);
ret = __bch2_btree_node_hash_insert(bc, b);
int ret = 0;
lockdep_assert_held(&bc->lock);
+wait_on_io:
+ if (b->flags & ((1U << BTREE_NODE_dirty)|
+ (1U << BTREE_NODE_read_in_flight)|
+ (1U << BTREE_NODE_write_in_flight))) {
+ if (!flush)
+ return -ENOMEM;
- if (!six_trylock_intent(&b->lock))
+ /* XXX: waiting on IO with btree cache lock held */
+ bch2_btree_node_wait_on_read(b);
+ bch2_btree_node_wait_on_write(b);
+ }
+
+ if (!six_trylock_intent(&b->c.lock))
return -ENOMEM;
- if (!six_trylock_write(&b->lock))
+ if (!six_trylock_write(&b->c.lock))
goto out_unlock_intent;
+ /* recheck under lock */
+ if (b->flags & ((1U << BTREE_NODE_read_in_flight)|
+ (1U << BTREE_NODE_write_in_flight))) {
+ if (!flush)
+ goto out_unlock;
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
+ goto wait_on_io;
+ }
+
if (btree_node_noevict(b))
goto out_unlock;
if (!btree_node_may_write(b))
goto out_unlock;
- if (btree_node_dirty(b) &&
- test_bit(BCH_FS_HOLD_BTREE_WRITES, &c->flags))
- goto out_unlock;
-
- if (btree_node_dirty(b) ||
- btree_node_write_in_flight(b) ||
- btree_node_read_in_flight(b)) {
- if (!flush)
+ if (btree_node_dirty(b)) {
+ if (!flush ||
+ test_bit(BCH_FS_HOLD_BTREE_WRITES, &c->flags))
goto out_unlock;
-
- wait_on_bit_io(&b->flags, BTREE_NODE_read_in_flight,
- TASK_UNINTERRUPTIBLE);
-
/*
* Using the underscore version because we don't want to compact
* bsets after the write, since this node is about to be evicted
* - unless btree verify mode is enabled, since it runs out of
* the post write cleanup:
*/
- if (verify_btree_ondisk(c))
+ if (bch2_verify_btree_ondisk)
bch2_btree_node_write(c, b, SIX_LOCK_intent);
else
- __bch2_btree_node_write(c, b, SIX_LOCK_read);
+ __bch2_btree_node_write(c, b, false);
- /* wait for any in flight btree write */
- btree_node_wait_on_io(b);
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
+ goto wait_on_io;
}
out:
if (b->hash_val && !ret)
trace_btree_node_reap(c, b);
return ret;
out_unlock:
- six_unlock_write(&b->lock);
+ six_unlock_write(&b->c.lock);
out_unlock_intent:
- six_unlock_intent(&b->lock);
+ six_unlock_intent(&b->c.lock);
ret = -ENOMEM;
goto out;
}
unsigned long can_free;
unsigned long touched = 0;
unsigned long freed = 0;
- unsigned i;
+ unsigned i, flags;
- if (btree_shrinker_disabled(c))
+ if (bch2_btree_shrinker_disabled)
return SHRINK_STOP;
/* Return -1 if we can't do anything right now */
- if (sc->gfp_mask & __GFP_IO)
+ if (sc->gfp_mask & __GFP_FS)
mutex_lock(&bc->lock);
else if (!mutex_trylock(&bc->lock))
return -1;
+ flags = memalloc_nofs_save();
+
/*
* It's _really_ critical that we don't free too many btree nodes - we
* have to always leave ourselves a reserve. The reserve is how we
if (++i > 3 &&
!btree_node_reclaim(c, b)) {
btree_node_data_free(c, b);
- six_unlock_write(&b->lock);
- six_unlock_intent(&b->lock);
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
freed++;
}
}
mutex_unlock(&bc->lock);
bch2_btree_node_hash_remove(bc, b);
- six_unlock_write(&b->lock);
- six_unlock_intent(&b->lock);
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
if (freed >= nr)
goto out;
- if (sc->gfp_mask & __GFP_IO)
+ if (sc->gfp_mask & __GFP_FS)
mutex_lock(&bc->lock);
else if (!mutex_trylock(&bc->lock))
goto out;
mutex_unlock(&bc->lock);
out:
+ memalloc_nofs_restore(flags);
return (unsigned long) freed * btree_pages(c);
}
btree_cache.shrink);
struct btree_cache *bc = &c->btree_cache;
- if (btree_shrinker_disabled(c))
+ if (bch2_btree_shrinker_disabled)
return 0;
return btree_cache_can_free(bc) * btree_pages(c);
{
struct btree_cache *bc = &c->btree_cache;
struct btree *b;
- unsigned i;
+ unsigned i, flags;
if (bc->shrink.list.next)
unregister_shrinker(&bc->shrink);
+ /* vfree() can allocate memory: */
+ flags = memalloc_nofs_save();
mutex_lock(&bc->lock);
-#ifdef CONFIG_BCACHEFS_DEBUG
if (c->verify_data)
list_move(&c->verify_data->list, &bc->live);
kvpfree(c->verify_ondisk, btree_bytes(c));
-#endif
for (i = 0; i < BTREE_ID_NR; i++)
if (c->btree_roots[i].b)
if (btree_node_dirty(b))
bch2_btree_complete_write(c, b, btree_current_write(b));
- clear_btree_node_dirty(b);
+ clear_btree_node_dirty(c, b);
btree_node_data_free(c, b);
}
+ BUG_ON(atomic_read(&c->btree_cache.dirty));
+
while (!list_empty(&bc->freed)) {
b = list_first_entry(&bc->freed, struct btree, list);
list_del(&b->list);
+ six_lock_pcpu_free(&b->c.lock);
kfree(b);
}
mutex_unlock(&bc->lock);
+ memalloc_nofs_restore(flags);
if (bc->table_init_done)
rhashtable_destroy(&bc->table);
bch2_recalc_btree_reserve(c);
for (i = 0; i < bc->reserve; i++)
- if (!btree_node_mem_alloc(c, GFP_KERNEL)) {
+ if (!__bch2_btree_node_mem_alloc(c)) {
ret = -ENOMEM;
goto out;
}
list_splice_init(&bc->live, &bc->freeable);
-#ifdef CONFIG_BCACHEFS_DEBUG
mutex_init(&c->verify_lock);
- c->verify_ondisk = kvpmalloc(btree_bytes(c), GFP_KERNEL);
- if (!c->verify_ondisk) {
- ret = -ENOMEM;
- goto out;
- }
-
- c->verify_data = btree_node_mem_alloc(c, GFP_KERNEL);
- if (!c->verify_data) {
- ret = -ENOMEM;
- goto out;
- }
-
- list_del_init(&c->verify_data->list);
-#endif
-
bc->shrink.count_objects = bch2_btree_cache_count;
bc->shrink.scan_objects = bch2_btree_cache_scan;
bc->shrink.seeks = 4;
bc->shrink.batch = btree_pages(c) * 2;
- register_shrinker(&bc->shrink);
+ ret = register_shrinker(&bc->shrink);
out:
pr_verbose_init(c->opts, "ret %i", ret);
return ret;
*/
list_for_each_entry(b, &bc->freeable, list)
if (!btree_node_reclaim(c, b))
- goto out_unlock;
+ goto got_node;
/*
* We never free struct btree itself, just the memory that holds the on
* disk node. Check the freed list before allocating a new one:
*/
list_for_each_entry(b, &bc->freed, list)
- if (!btree_node_reclaim(c, b)) {
- btree_node_data_alloc(c, b, __GFP_NOWARN|GFP_NOIO);
- if (b->data)
- goto out_unlock;
+ if (!btree_node_reclaim(c, b))
+ goto got_node;
- six_unlock_write(&b->lock);
- six_unlock_intent(&b->lock);
+ b = NULL;
+got_node:
+ if (b)
+ list_del_init(&b->list);
+ mutex_unlock(&bc->lock);
+
+ if (!b) {
+ b = __btree_node_mem_alloc(c);
+ if (!b)
goto err;
- }
- b = btree_node_mem_alloc(c, __GFP_NOWARN|GFP_NOIO);
- if (!b)
- goto err;
+ BUG_ON(!six_trylock_intent(&b->c.lock));
+ BUG_ON(!six_trylock_write(&b->c.lock));
+ }
+
+ if (!b->data) {
+ if (btree_node_data_alloc(c, b, __GFP_NOWARN|GFP_KERNEL))
+ goto err;
+
+ mutex_lock(&bc->lock);
+ bc->used++;
+ mutex_unlock(&bc->lock);
+ }
- BUG_ON(!six_trylock_intent(&b->lock));
- BUG_ON(!six_trylock_write(&b->lock));
-out_unlock:
BUG_ON(btree_node_hashed(b));
+ BUG_ON(btree_node_dirty(b));
BUG_ON(btree_node_write_in_flight(b));
-
- list_del_init(&b->list);
- mutex_unlock(&bc->lock);
- memalloc_nofs_restore(flags);
out:
b->flags = 0;
b->written = 0;
b->sib_u64s[0] = 0;
b->sib_u64s[1] = 0;
b->whiteout_u64s = 0;
- bch2_btree_keys_init(b, &c->expensive_debug_checks);
+ bch2_btree_keys_init(b);
+ set_btree_node_accessed(b);
bch2_time_stats_update(&c->times[BCH_TIME_btree_node_mem_alloc],
start_time);
+ memalloc_nofs_restore(flags);
return b;
err:
+ mutex_lock(&bc->lock);
+
+ if (b) {
+ list_add(&b->list, &bc->freed);
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
+ }
+
/* Try to cannibalize another cached btree node: */
if (bc->alloc_lock == current) {
b = btree_node_cannibalize(c);
}
mutex_unlock(&bc->lock);
+ memalloc_nofs_restore(flags);
return ERR_PTR(-ENOMEM);
}
static noinline struct btree *bch2_btree_node_fill(struct bch_fs *c,
struct btree_iter *iter,
const struct bkey_i *k,
+ enum btree_id btree_id,
unsigned level,
enum six_lock_type lock_type,
bool sync)
{
struct btree_cache *bc = &c->btree_cache;
struct btree *b;
+ u32 seq;
+ BUG_ON(level + 1 >= BTREE_MAX_DEPTH);
/*
* Parent node must be locked, else we could read in a btree node that's
* been freed:
*/
- BUG_ON(!btree_node_locked(iter, level + 1));
- BUG_ON(level >= BTREE_MAX_DEPTH);
+ if (iter && !bch2_btree_node_relock(iter, level + 1))
+ return ERR_PTR(-EINTR);
b = bch2_btree_node_mem_alloc(c);
if (IS_ERR(b))
return b;
bkey_copy(&b->key, k);
- if (bch2_btree_node_hash_insert(bc, b, level, iter->btree_id)) {
+ if (bch2_btree_node_hash_insert(bc, b, level, btree_id)) {
/* raced with another fill: */
/* mark as unhashed... */
list_add(&b->list, &bc->freeable);
mutex_unlock(&bc->lock);
- six_unlock_write(&b->lock);
- six_unlock_intent(&b->lock);
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
return NULL;
}
- /*
- * If the btree node wasn't cached, we can't drop our lock on
- * the parent until after it's added to the cache - because
- * otherwise we could race with a btree_split() freeing the node
- * we're trying to lock.
- *
- * But the deadlock described below doesn't exist in this case,
- * so it's safe to not drop the parent lock until here:
- */
- if (btree_node_read_locked(iter, level + 1))
- btree_node_unlock(iter, level + 1);
+ set_btree_node_read_in_flight(b);
- bch2_btree_node_read(c, b, sync);
+ six_unlock_write(&b->c.lock);
+ seq = b->c.lock.state.seq;
+ six_unlock_intent(&b->c.lock);
- six_unlock_write(&b->lock);
+ /* Unlock before doing IO: */
+ if (iter && sync)
+ bch2_trans_unlock(iter->trans);
- if (!sync) {
- six_unlock_intent(&b->lock);
+ bch2_btree_node_read(c, b, sync);
+
+ if (!sync)
return NULL;
- }
- if (lock_type == SIX_LOCK_read)
- six_lock_downgrade(&b->lock);
+ /*
+ * XXX: this will probably always fail because btree_iter_relock()
+ * currently fails for iterators that aren't pointed at a valid btree
+ * node
+ */
+ if (iter &&
+ (!bch2_trans_relock(iter->trans) ||
+ !bch2_btree_iter_relock(iter, _THIS_IP_)))
+ return ERR_PTR(-EINTR);
+
+ if (!six_relock_type(&b->c.lock, lock_type, seq))
+ return ERR_PTR(-EINTR);
return b;
}
+static int lock_node_check_fn(struct six_lock *lock, void *p)
+{
+ struct btree *b = container_of(lock, struct btree, c.lock);
+ const struct bkey_i *k = p;
+
+ return b->hash_val == btree_ptr_hash_val(k) ? 0 : -1;
+}
+
+static noinline void btree_bad_header(struct bch_fs *c, struct btree *b)
+{
+ char buf1[100], buf2[100], buf3[100], buf4[100];
+
+ if (!test_bit(BCH_FS_INITIAL_GC_DONE, &c->flags))
+ return;
+
+ bch2_bpos_to_text(&PBUF(buf1), b->key.k.type == KEY_TYPE_btree_ptr_v2
+ ? bkey_i_to_btree_ptr_v2(&b->key)->v.min_key
+ : POS_MIN);
+ bch2_bpos_to_text(&PBUF(buf2), b->data->min_key);
+
+ bch2_bpos_to_text(&PBUF(buf3), b->key.k.p);
+ bch2_bpos_to_text(&PBUF(buf4), b->data->max_key);
+ bch2_fs_inconsistent(c, "btree node header doesn't match ptr\n"
+ "btree: ptr %u header %llu\n"
+ "level: ptr %u header %llu\n"
+ "min ptr %s node header %s\n"
+ "max ptr %s node header %s",
+ b->c.btree_id, BTREE_NODE_ID(b->data),
+ b->c.level, BTREE_NODE_LEVEL(b->data),
+ buf1, buf2, buf3, buf4);
+}
+
+static inline void btree_check_header(struct bch_fs *c, struct btree *b)
+{
+ if (b->c.btree_id != BTREE_NODE_ID(b->data) ||
+ b->c.level != BTREE_NODE_LEVEL(b->data) ||
+ bpos_cmp(b->data->max_key, b->key.k.p) ||
+ (b->key.k.type == KEY_TYPE_btree_ptr_v2 &&
+ bpos_cmp(b->data->min_key,
+ bkey_i_to_btree_ptr_v2(&b->key)->v.min_key)))
+ btree_bad_header(c, b);
+}
+
/**
* bch_btree_node_get - find a btree node in the cache and lock it, reading it
* in from disk if necessary.
*/
struct btree *bch2_btree_node_get(struct bch_fs *c, struct btree_iter *iter,
const struct bkey_i *k, unsigned level,
- enum six_lock_type lock_type)
+ enum six_lock_type lock_type,
+ unsigned long trace_ip)
{
struct btree_cache *bc = &c->btree_cache;
struct btree *b;
struct bset_tree *t;
- /*
- * XXX: locking optimization
- *
- * we can make the locking looser here - caller can drop lock on parent
- * node before locking child node (and potentially blocking): we just
- * have to have bch2_btree_node_fill() call relock on the parent and
- * return -EINTR if that fails
- */
- EBUG_ON(!btree_node_locked(iter, level + 1));
EBUG_ON(level >= BTREE_MAX_DEPTH);
+
+ b = btree_node_mem_ptr(k);
+ if (b)
+ goto lock_node;
retry:
b = btree_cache_find(bc, k);
if (unlikely(!b)) {
* else we could read in a btree node from disk that's been
* freed:
*/
- b = bch2_btree_node_fill(c, iter, k, level, lock_type, true);
+ b = bch2_btree_node_fill(c, iter, k, iter->btree_id,
+ level, lock_type, true);
/* We raced and found the btree node in the cache */
if (!b)
if (IS_ERR(b))
return b;
} else {
+lock_node:
/*
* There's a potential deadlock with splits and insertions into
* interior nodes we have to avoid:
if (btree_node_read_locked(iter, level + 1))
btree_node_unlock(iter, level + 1);
- if (!btree_node_lock(b, k->k.p, level, iter, lock_type))
+ if (!btree_node_lock(b, k->k.p, level, iter, lock_type,
+ lock_node_check_fn, (void *) k, trace_ip)) {
+ if (b->hash_val != btree_ptr_hash_val(k))
+ goto retry;
return ERR_PTR(-EINTR);
+ }
if (unlikely(b->hash_val != btree_ptr_hash_val(k) ||
- b->level != level ||
+ b->c.level != level ||
race_fault())) {
- six_unlock_type(&b->lock, lock_type);
+ six_unlock_type(&b->c.lock, lock_type);
if (bch2_btree_node_relock(iter, level + 1))
goto retry;
- trace_trans_restart_btree_node_reused(iter->trans->ip);
+ trace_trans_restart_btree_node_reused(iter->trans->ip,
+ trace_ip,
+ iter->btree_id,
+ &iter->real_pos);
return ERR_PTR(-EINTR);
}
}
- wait_on_bit_io(&b->flags, BTREE_NODE_read_in_flight,
- TASK_UNINTERRUPTIBLE);
+ if (unlikely(btree_node_read_in_flight(b))) {
+ u32 seq = b->c.lock.state.seq;
+
+ six_unlock_type(&b->c.lock, lock_type);
+ bch2_trans_unlock(iter->trans);
+
+ bch2_btree_node_wait_on_read(b);
+
+ /*
+ * XXX: check if this always fails - btree_iter_relock()
+ * currently fails for iterators that aren't pointed at a valid
+ * btree node
+ */
+ if (iter &&
+ (!bch2_trans_relock(iter->trans) ||
+ !bch2_btree_iter_relock(iter, _THIS_IP_)))
+ return ERR_PTR(-EINTR);
+
+ if (!six_relock_type(&b->c.lock, lock_type, seq))
+ goto retry;
+ }
prefetch(b->aux_data);
}
/* avoid atomic set bit if it's not needed: */
- if (btree_node_accessed(b))
+ if (!btree_node_accessed(b))
set_btree_node_accessed(b);
if (unlikely(btree_node_read_error(b))) {
- six_unlock_type(&b->lock, lock_type);
+ six_unlock_type(&b->c.lock, lock_type);
return ERR_PTR(-EIO);
}
- EBUG_ON(b->btree_id != iter->btree_id ||
- BTREE_NODE_LEVEL(b->data) != level ||
- bkey_cmp(b->data->max_key, k->k.p));
+ EBUG_ON(b->c.btree_id != iter->btree_id);
+ EBUG_ON(BTREE_NODE_LEVEL(b->data) != level);
+ btree_check_header(c, b);
return b;
}
-struct btree *bch2_btree_node_get_sibling(struct bch_fs *c,
- struct btree_iter *iter,
- struct btree *b,
- enum btree_node_sibling sib)
+struct btree *bch2_btree_node_get_noiter(struct bch_fs *c,
+ const struct bkey_i *k,
+ enum btree_id btree_id,
+ unsigned level,
+ bool nofill)
{
- struct btree_trans *trans = iter->trans;
- struct btree *parent;
- struct btree_node_iter node_iter;
- struct bkey_packed *k;
- BKEY_PADDED(k) tmp;
- struct btree *ret = NULL;
- unsigned level = b->level;
-
- parent = btree_iter_node(iter, level + 1);
- if (!parent)
- return NULL;
-
- if (!bch2_btree_node_relock(iter, level + 1)) {
- ret = ERR_PTR(-EINTR);
- goto out;
- }
-
- node_iter = iter->l[parent->level].iter;
-
- k = bch2_btree_node_iter_peek_all(&node_iter, parent);
- BUG_ON(bkey_cmp_left_packed(parent, k, &b->key.k.p));
-
- k = sib == btree_prev_sib
- ? bch2_btree_node_iter_prev(&node_iter, parent)
- : (bch2_btree_node_iter_advance(&node_iter, parent),
- bch2_btree_node_iter_peek(&node_iter, parent));
- if (!k)
- goto out;
-
- bch2_bkey_unpack(parent, &tmp.k, k);
-
- ret = bch2_btree_node_get(c, iter, &tmp.k, level,
- SIX_LOCK_intent);
+ struct btree_cache *bc = &c->btree_cache;
+ struct btree *b;
+ struct bset_tree *t;
+ int ret;
- if (PTR_ERR_OR_ZERO(ret) == -EINTR && !trans->nounlock) {
- struct btree_iter *linked;
+ EBUG_ON(level >= BTREE_MAX_DEPTH);
- if (!bch2_btree_node_relock(iter, level + 1))
+ b = btree_node_mem_ptr(k);
+ if (b)
+ goto lock_node;
+retry:
+ b = btree_cache_find(bc, k);
+ if (unlikely(!b)) {
+ if (nofill)
goto out;
- /*
- * We might have got -EINTR because trylock failed, and we're
- * holding other locks that would cause us to deadlock:
- */
- trans_for_each_iter(trans, linked)
- if (btree_iter_cmp(iter, linked) < 0)
- __bch2_btree_iter_unlock(linked);
-
- if (sib == btree_prev_sib)
- btree_node_unlock(iter, level);
+ b = bch2_btree_node_fill(c, NULL, k, btree_id,
+ level, SIX_LOCK_read, true);
- ret = bch2_btree_node_get(c, iter, &tmp.k, level,
- SIX_LOCK_intent);
+ /* We raced and found the btree node in the cache */
+ if (!b)
+ goto retry;
- /*
- * before btree_iter_relock() calls btree_iter_verify_locks():
- */
- if (btree_lock_want(iter, level + 1) == BTREE_NODE_UNLOCKED)
- btree_node_unlock(iter, level + 1);
+ if (IS_ERR(b) &&
+ !bch2_btree_cache_cannibalize_lock(c, NULL))
+ goto retry;
- if (!bch2_btree_node_relock(iter, level)) {
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_RELOCK);
+ if (IS_ERR(b))
+ goto out;
+ } else {
+lock_node:
+ ret = six_lock_read(&b->c.lock, lock_node_check_fn, (void *) k);
+ if (ret)
+ goto retry;
- if (!IS_ERR(ret)) {
- six_unlock_intent(&ret->lock);
- ret = ERR_PTR(-EINTR);
- }
+ if (unlikely(b->hash_val != btree_ptr_hash_val(k) ||
+ b->c.btree_id != btree_id ||
+ b->c.level != level)) {
+ six_unlock_read(&b->c.lock);
+ goto retry;
}
-
- bch2_trans_relock(trans);
}
-out:
- if (btree_lock_want(iter, level + 1) == BTREE_NODE_UNLOCKED)
- btree_node_unlock(iter, level + 1);
-
- if (PTR_ERR_OR_ZERO(ret) == -EINTR)
- bch2_btree_iter_upgrade(iter, level + 2);
- BUG_ON(!IS_ERR(ret) && !btree_node_locked(iter, level));
+ /* XXX: waiting on IO with btree locks held: */
+ __bch2_btree_node_wait_on_read(b);
- if (!IS_ERR_OR_NULL(ret)) {
- struct btree *n1 = ret, *n2 = b;
+ prefetch(b->aux_data);
- if (sib != btree_prev_sib)
- swap(n1, n2);
+ for_each_bset(b, t) {
+ void *p = (u64 *) b->aux_data + t->aux_data_offset;
- BUG_ON(bkey_cmp(btree_type_successor(n1->btree_id,
- n1->key.k.p),
- n2->data->min_key));
+ prefetch(p + L1_CACHE_BYTES * 0);
+ prefetch(p + L1_CACHE_BYTES * 1);
+ prefetch(p + L1_CACHE_BYTES * 2);
}
- bch2_btree_trans_verify_locks(trans);
+ /* avoid atomic set bit if it's not needed: */
+ if (!btree_node_accessed(b))
+ set_btree_node_accessed(b);
- return ret;
+ if (unlikely(btree_node_read_error(b))) {
+ six_unlock_read(&b->c.lock);
+ b = ERR_PTR(-EIO);
+ goto out;
+ }
+
+ EBUG_ON(b->c.btree_id != btree_id);
+ EBUG_ON(BTREE_NODE_LEVEL(b->data) != level);
+ btree_check_header(c, b);
+out:
+ bch2_btree_cache_cannibalize_unlock(c);
+ return b;
}
void bch2_btree_node_prefetch(struct bch_fs *c, struct btree_iter *iter,
- const struct bkey_i *k, unsigned level)
+ const struct bkey_i *k,
+ enum btree_id btree_id, unsigned level)
{
struct btree_cache *bc = &c->btree_cache;
struct btree *b;
- BUG_ON(!btree_node_locked(iter, level + 1));
+ BUG_ON(iter && !btree_node_locked(iter, level + 1));
BUG_ON(level >= BTREE_MAX_DEPTH);
b = btree_cache_find(bc, k);
if (b)
return;
- bch2_btree_node_fill(c, iter, k, level, SIX_LOCK_read, false);
+ bch2_btree_node_fill(c, iter, k, btree_id, level, SIX_LOCK_read, false);
+}
+
+void bch2_btree_node_evict(struct bch_fs *c, const struct bkey_i *k)
+{
+ struct btree_cache *bc = &c->btree_cache;
+ struct btree *b;
+
+ b = btree_cache_find(bc, k);
+ if (!b)
+ return;
+wait_on_io:
+ /* not allowed to wait on io with btree locks held: */
+
+ /* XXX we're called from btree_gc which will be holding other btree
+ * nodes locked
+ * */
+ __bch2_btree_node_wait_on_read(b);
+ __bch2_btree_node_wait_on_write(b);
+
+ six_lock_intent(&b->c.lock, NULL, NULL);
+ six_lock_write(&b->c.lock, NULL, NULL);
+
+ if (btree_node_dirty(b)) {
+ __bch2_btree_node_write(c, b, false);
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
+ goto wait_on_io;
+ }
+
+ BUG_ON(btree_node_dirty(b));
+
+ mutex_lock(&bc->lock);
+ btree_node_data_free(c, b);
+ bch2_btree_node_hash_remove(bc, b);
+ mutex_unlock(&bc->lock);
+
+ six_unlock_write(&b->c.lock);
+ six_unlock_intent(&b->c.lock);
}
void bch2_btree_node_to_text(struct printbuf *out, struct bch_fs *c,
bch2_btree_keys_stats(b, &stats);
- pr_buf(out,
- "l %u %llu:%llu - %llu:%llu:\n"
- " ptrs: ",
- b->level,
- b->data->min_key.inode,
- b->data->min_key.offset,
- b->data->max_key.inode,
- b->data->max_key.offset);
+ pr_buf(out, "l %u ", b->c.level);
+ bch2_bpos_to_text(out, b->data->min_key);
+ pr_buf(out, " - ");
+ bch2_bpos_to_text(out, b->data->max_key);
+ pr_buf(out, ":\n"
+ " ptrs: ");
bch2_val_to_text(out, c, bkey_i_to_s_c(&b->key));
+
pr_buf(out, "\n"
" format: u64s %u fields %u %u %u %u %u\n"
" unpack fn len: %u\n"
" bytes used %zu/%zu (%zu%% full)\n"
- " sib u64s: %u, %u (merge threshold %zu)\n"
+ " sib u64s: %u, %u (merge threshold %u)\n"
" nr packed keys %u\n"
" nr unpacked keys %u\n"
" floats %zu\n"
b->nr.live_u64s * 100 / btree_max_u64s(c),
b->sib_u64s[0],
b->sib_u64s[1],
- BTREE_FOREGROUND_MERGE_THRESHOLD(c),
+ c->btree_foreground_merge_threshold,
b->nr.packed_keys,
b->nr.unpacked_keys,
stats.floats,
stats.failed);
}
+
+void bch2_btree_cache_to_text(struct printbuf *out, struct bch_fs *c)
+{
+ pr_buf(out, "nr nodes:\t\t%u\n", c->btree_cache.used);
+ pr_buf(out, "nr dirty:\t\t%u\n", atomic_read(&c->btree_cache.dirty));
+ pr_buf(out, "cannibalize lock:\t%p\n", c->btree_cache.alloc_lock);
+}