+// SPDX-License-Identifier: GPL-2.0
#include "bcachefs.h"
#include "bkey_methods.h"
+#include "bkey_buf.h"
#include "btree_cache.h"
#include "btree_iter.h"
+#include "btree_key_cache.h"
#include "btree_locking.h"
+#include "btree_update.h"
#include "debug.h"
+#include "error.h"
#include "extents.h"
+#include "journal.h"
+#include "replicas.h"
#include <linux/prefetch.h>
#include <trace/events/bcachefs.h>
-static inline struct bkey_s_c __btree_iter_peek_all(struct btree_iter *,
- struct btree_iter_level *,
- struct bkey *);
+static void btree_iter_set_search_pos(struct btree_iter *, struct bpos);
+static struct btree_iter *btree_iter_child_alloc(struct btree_iter *, unsigned long);
+static struct btree_iter *btree_trans_iter_alloc(struct btree_trans *);
+static void btree_iter_copy(struct btree_iter *, struct btree_iter *);
-#define BTREE_ITER_NOT_END ((struct btree *) 1)
+static inline struct bpos bkey_successor(struct btree_iter *iter, struct bpos p)
+{
+ EBUG_ON(btree_iter_type(iter) == BTREE_ITER_NODES);
+
+ /* Are we iterating over keys in all snapshots? */
+ if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
+ p = bpos_successor(p);
+ } else {
+ p = bpos_nosnap_successor(p);
+ p.snapshot = iter->snapshot;
+ }
+
+ return p;
+}
+
+static inline struct bpos bkey_predecessor(struct btree_iter *iter, struct bpos p)
+{
+ EBUG_ON(btree_iter_type(iter) == BTREE_ITER_NODES);
+
+ /* Are we iterating over keys in all snapshots? */
+ if (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) {
+ p = bpos_predecessor(p);
+ } else {
+ p = bpos_nosnap_predecessor(p);
+ p.snapshot = iter->snapshot;
+ }
+
+ return p;
+}
static inline bool is_btree_node(struct btree_iter *iter, unsigned l)
{
return l < BTREE_MAX_DEPTH &&
- iter->l[l].b &&
- iter->l[l].b != BTREE_ITER_NOT_END;
+ (unsigned long) iter->l[l].b >= 128;
}
-/* Returns < 0 if @k is before iter pos, > 0 if @k is after */
-static inline int __btree_iter_pos_cmp(struct btree_iter *iter,
- const struct btree *b,
- const struct bkey_packed *k,
- bool interior_node)
+static inline struct bpos btree_iter_search_key(struct btree_iter *iter)
{
- int cmp = bkey_cmp_left_packed(b, k, &iter->pos);
+ struct bpos pos = iter->pos;
- if (cmp)
- return cmp;
- if (bkey_deleted(k))
- return -1;
+ if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
+ bkey_cmp(pos, POS_MAX))
+ pos = bkey_successor(iter, pos);
+ return pos;
+}
- /*
- * Normally, for extents we want the first key strictly greater than
- * the iterator position - with the exception that for interior nodes,
- * we don't want to advance past the last key if the iterator position
- * is POS_MAX:
- */
- if (iter->flags & BTREE_ITER_IS_EXTENTS &&
- (!interior_node ||
- bkey_cmp_left_packed_byval(b, k, POS_MAX)))
- return -1;
- return 1;
+static inline bool btree_iter_pos_before_node(struct btree_iter *iter,
+ struct btree *b)
+{
+ return bpos_cmp(iter->real_pos, b->data->min_key) < 0;
+}
+
+static inline bool btree_iter_pos_after_node(struct btree_iter *iter,
+ struct btree *b)
+{
+ return bpos_cmp(b->key.k.p, iter->real_pos) < 0;
}
-static inline int btree_iter_pos_cmp(struct btree_iter *iter,
- const struct btree *b,
- const struct bkey_packed *k)
+static inline bool btree_iter_pos_in_node(struct btree_iter *iter,
+ struct btree *b)
{
- return __btree_iter_pos_cmp(iter, b, k, b->level != 0);
+ return iter->btree_id == b->c.btree_id &&
+ !btree_iter_pos_before_node(iter, b) &&
+ !btree_iter_pos_after_node(iter, b);
}
/* Btree node locking: */
-/*
- * Updates the saved lock sequence number, so that bch2_btree_node_relock() will
- * succeed:
- */
void bch2_btree_node_unlock_write(struct btree *b, struct btree_iter *iter)
{
- struct btree_iter *linked;
-
- EBUG_ON(iter->l[b->level].b != b);
- EBUG_ON(iter->l[b->level].lock_seq + 1 != b->lock.state.seq);
-
- trans_for_each_iter_with_node(iter->trans, b, linked)
- linked->l[b->level].lock_seq += 2;
-
- six_unlock_write(&b->lock);
+ bch2_btree_node_unlock_write_inlined(b, iter);
}
void __bch2_btree_node_lock_write(struct btree *b, struct btree_iter *iter)
struct btree_iter *linked;
unsigned readers = 0;
- EBUG_ON(btree_node_read_locked(iter, b->level));
+ EBUG_ON(!btree_node_intent_locked(iter, b->c.level));
trans_for_each_iter(iter->trans, linked)
- if (linked->l[b->level].b == b &&
- btree_node_read_locked(linked, b->level))
+ if (linked->l[b->c.level].b == b &&
+ btree_node_read_locked(linked, b->c.level))
readers++;
/*
* locked:
*/
atomic64_sub(__SIX_VAL(read_lock, readers),
- &b->lock.state.counter);
+ &b->c.lock.state.counter);
btree_node_lock_type(iter->trans->c, b, SIX_LOCK_write);
atomic64_add(__SIX_VAL(read_lock, readers),
- &b->lock.state.counter);
+ &b->c.lock.state.counter);
}
bool __bch2_btree_node_relock(struct btree_iter *iter, unsigned level)
struct btree *b = btree_iter_node(iter, level);
int want = __btree_lock_want(iter, level);
- if (!b || b == BTREE_ITER_NOT_END)
+ if (!is_btree_node(iter, level))
return false;
if (race_fault())
return false;
- if (!six_relock_type(&b->lock, want, iter->l[level].lock_seq) &&
- !(iter->l[level].lock_seq >> 1 == b->lock.state.seq >> 1 &&
- btree_node_lock_increment(iter, b, level, want)))
+ if (six_relock_type(&b->c.lock, want, iter->l[level].lock_seq) ||
+ (btree_node_lock_seq_matches(iter, b, level) &&
+ btree_node_lock_increment(iter->trans, b, level, want))) {
+ mark_btree_node_locked(iter, level, want);
+ return true;
+ } else {
return false;
-
- mark_btree_node_locked(iter, level, want);
- return true;
+ }
}
static bool bch2_btree_node_upgrade(struct btree_iter *iter, unsigned level)
return false;
if (btree_node_locked(iter, level)
- ? six_lock_tryupgrade(&b->lock)
- : six_relock_type(&b->lock, SIX_LOCK_intent, iter->l[level].lock_seq))
+ ? six_lock_tryupgrade(&b->c.lock)
+ : six_relock_type(&b->c.lock, SIX_LOCK_intent, iter->l[level].lock_seq))
goto success;
- if (iter->l[level].lock_seq >> 1 == b->lock.state.seq >> 1 &&
- btree_node_lock_increment(iter, b, level, BTREE_NODE_INTENT_LOCKED)) {
+ if (btree_node_lock_seq_matches(iter, b, level) &&
+ btree_node_lock_increment(iter->trans, b, level, BTREE_NODE_INTENT_LOCKED)) {
btree_node_unlock(iter, level);
goto success;
}
return true;
}
-static inline bool btree_iter_get_locks(struct btree_iter *iter,
- bool upgrade)
+static inline bool btree_iter_get_locks(struct btree_iter *iter, bool upgrade,
+ unsigned long trace_ip)
{
unsigned l = iter->level;
int fail_idx = -1;
if (!(upgrade
? bch2_btree_node_upgrade(iter, l)
: bch2_btree_node_relock(iter, l))) {
+ (upgrade
+ ? trace_node_upgrade_fail
+ : trace_node_relock_fail)(iter->trans->ip, trace_ip,
+ iter->btree_id, &iter->real_pos,
+ l, iter->l[l].lock_seq,
+ is_btree_node(iter, l)
+ ? 0
+ : (unsigned long) iter->l[l].b,
+ is_btree_node(iter, l)
+ ? iter->l[l].b->c.lock.state.seq
+ : 0);
+
fail_idx = l;
btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
}
*/
while (fail_idx >= 0) {
btree_node_unlock(iter, fail_idx);
- iter->l[fail_idx].b = BTREE_ITER_NOT_END;
+ iter->l[fail_idx].b = BTREE_ITER_NO_NODE_GET_LOCKS;
--fail_idx;
}
return iter->uptodate < BTREE_ITER_NEED_RELOCK;
}
+static struct bpos btree_node_pos(struct btree_bkey_cached_common *_b,
+ enum btree_iter_type type)
+{
+ return type != BTREE_ITER_CACHED
+ ? container_of(_b, struct btree, c)->key.k.p
+ : container_of(_b, struct bkey_cached, c)->key.pos;
+}
+
/* Slowpath: */
bool __bch2_btree_node_lock(struct btree *b, struct bpos pos,
- unsigned level,
- struct btree_iter *iter,
- enum six_lock_type type,
- bool may_drop_locks)
+ unsigned level, struct btree_iter *iter,
+ enum six_lock_type type,
+ six_lock_should_sleep_fn should_sleep_fn, void *p,
+ unsigned long ip)
{
- struct btree_iter *linked;
- bool ret = true;
+ struct btree_trans *trans = iter->trans;
+ struct btree_iter *linked, *deadlock_iter = NULL;
+ u64 start_time = local_clock();
+ unsigned reason = 9;
+ bool ret;
/* Check if it's safe to block: */
- trans_for_each_iter(iter->trans, linked) {
+ trans_for_each_iter(trans, linked) {
if (!linked->nodes_locked)
continue;
- /* * Must lock btree nodes in key order: */
- if (__btree_iter_cmp(iter->btree_id, pos, linked) < 0)
- ret = false;
-
/*
* Can't block taking an intent lock if we have _any_ nodes read
* locked:
*/
if (type == SIX_LOCK_intent &&
linked->nodes_locked != linked->nodes_intent_locked) {
- if (may_drop_locks) {
- linked->locks_want = max_t(unsigned,
- linked->locks_want,
- __fls(linked->nodes_locked) + 1);
- btree_iter_get_locks(linked, true);
+ deadlock_iter = linked;
+ reason = 1;
+ }
+
+ if (linked->btree_id != iter->btree_id) {
+ if (linked->btree_id > iter->btree_id) {
+ deadlock_iter = linked;
+ reason = 3;
+ }
+ continue;
+ }
+
+ /*
+ * Within the same btree, cached iterators come before non
+ * cached iterators:
+ */
+ if (btree_iter_is_cached(linked) != btree_iter_is_cached(iter)) {
+ if (btree_iter_is_cached(iter)) {
+ deadlock_iter = linked;
+ reason = 4;
}
- ret = false;
+ continue;
}
/*
* another iterator has possible descendants locked of the node
* we're about to lock, it must have the ancestors locked too:
*/
- if (linked->btree_id == iter->btree_id &&
- level > __fls(linked->nodes_locked)) {
- if (may_drop_locks) {
- linked->locks_want =
- max(level + 1, max_t(unsigned,
- linked->locks_want,
- iter->locks_want));
- btree_iter_get_locks(linked, true);
- }
- ret = false;
+ if (level > __fls(linked->nodes_locked)) {
+ deadlock_iter = linked;
+ reason = 5;
+ }
+
+ /* Must lock btree nodes in key order: */
+ if (btree_node_locked(linked, level) &&
+ bpos_cmp(pos, btree_node_pos((void *) linked->l[level].b,
+ btree_iter_type(linked))) <= 0) {
+ deadlock_iter = linked;
+ reason = 7;
+ BUG_ON(trans->in_traverse_all);
}
}
- if (ret)
- __btree_node_lock_type(iter->trans->c, b, type);
- else
- trans_restart();
+ if (unlikely(deadlock_iter)) {
+ trace_trans_restart_would_deadlock(iter->trans->ip, ip,
+ trans->in_traverse_all, reason,
+ deadlock_iter->btree_id,
+ btree_iter_type(deadlock_iter),
+ &deadlock_iter->real_pos,
+ iter->btree_id,
+ btree_iter_type(iter),
+ &pos);
+ return false;
+ }
+
+ if (six_trylock_type(&b->c.lock, type))
+ return true;
+
+#ifdef CONFIG_BCACHEFS_DEBUG
+ trans->locking_iter_idx = iter->idx;
+ trans->locking_pos = pos;
+ trans->locking_btree_id = iter->btree_id;
+ trans->locking_level = level;
+ trans->locking = b;
+#endif
+
+ ret = six_lock_type(&b->c.lock, type, should_sleep_fn, p) == 0;
+#ifdef CONFIG_BCACHEFS_DEBUG
+ trans->locking = NULL;
+#endif
+ if (ret)
+ bch2_time_stats_update(&trans->c->times[lock_to_time_stat(type)],
+ start_time);
return ret;
}
/* Btree iterator locking: */
#ifdef CONFIG_BCACHEFS_DEBUG
-void bch2_btree_iter_verify_locks(struct btree_iter *iter)
+static void bch2_btree_iter_verify_locks(struct btree_iter *iter)
{
unsigned l;
- BUG_ON((iter->flags & BTREE_ITER_NOUNLOCK) &&
- !btree_node_locked(iter, 0));
+ if (!(iter->trans->iters_linked & (1ULL << iter->idx))) {
+ BUG_ON(iter->nodes_locked);
+ return;
+ }
- for (l = 0; btree_iter_node(iter, l); l++) {
+ for (l = 0; is_btree_node(iter, l); l++) {
if (iter->uptodate >= BTREE_ITER_NEED_RELOCK &&
!btree_node_locked(iter, l))
continue;
trans_for_each_iter(trans, iter)
bch2_btree_iter_verify_locks(iter);
}
+#else
+static inline void bch2_btree_iter_verify_locks(struct btree_iter *iter) {}
#endif
__flatten
-static bool bch2_btree_iter_relock(struct btree_iter *iter)
+static bool bch2_btree_iter_relock(struct btree_iter *iter, unsigned long trace_ip)
{
- return iter->uptodate >= BTREE_ITER_NEED_RELOCK
- ? btree_iter_get_locks(iter, false)
- : true;
+ return btree_iter_get_locks(iter, false, trace_ip);
}
bool __bch2_btree_iter_upgrade(struct btree_iter *iter,
iter->locks_want = new_locks_want;
- if (btree_iter_get_locks(iter, true))
+ if (btree_iter_get_locks(iter, true, _THIS_IP_))
return true;
/*
- * Ancestor nodes must be locked before child nodes, so set locks_want
- * on iterators that might lock ancestors before us to avoid getting
- * -EINTR later:
+ * XXX: this is ugly - we'd prefer to not be mucking with other
+ * iterators in the btree_trans here.
+ *
+ * On failure to upgrade the iterator, setting iter->locks_want and
+ * calling get_locks() is sufficient to make bch2_btree_iter_traverse()
+ * get the locks we want on transaction restart.
+ *
+ * But if this iterator was a clone, on transaction restart what we did
+ * to this iterator isn't going to be preserved.
+ *
+ * Possibly we could add an iterator field for the parent iterator when
+ * an iterator is a copy - for now, we'll just upgrade any other
+ * iterators with the same btree id.
+ *
+ * The code below used to be needed to ensure ancestor nodes get locked
+ * before interior nodes - now that's handled by
+ * bch2_btree_iter_traverse_all().
*/
trans_for_each_iter(iter->trans, linked)
if (linked != iter &&
+ btree_iter_type(linked) == btree_iter_type(iter) &&
linked->btree_id == iter->btree_id &&
- btree_iter_cmp(linked, iter) <= 0 &&
linked->locks_want < new_locks_want) {
linked->locks_want = new_locks_want;
- btree_iter_get_locks(linked, true);
+ btree_iter_get_locks(linked, true, _THIS_IP_);
}
return false;
}
-bool __bch2_btree_iter_upgrade_nounlock(struct btree_iter *iter,
- unsigned new_locks_want)
-{
- unsigned l = iter->level;
-
- EBUG_ON(iter->locks_want >= new_locks_want);
-
- iter->locks_want = new_locks_want;
-
- do {
- if (!btree_iter_node(iter, l))
- break;
-
- if (!bch2_btree_node_upgrade(iter, l)) {
- iter->locks_want = l;
- return false;
- }
-
- l++;
- } while (l < iter->locks_want);
-
- return true;
-}
-
void __bch2_btree_iter_downgrade(struct btree_iter *iter,
- unsigned downgrade_to)
+ unsigned new_locks_want)
{
- struct btree_iter *linked;
unsigned l;
- /*
- * We downgrade linked iterators as well because btree_iter_upgrade
- * might have had to modify locks_want on linked iterators due to lock
- * ordering:
- */
- trans_for_each_iter(iter->trans, linked) {
- unsigned new_locks_want = downgrade_to ?:
- (linked->flags & BTREE_ITER_INTENT ? 1 : 0);
-
- if (linked->locks_want <= new_locks_want)
- continue;
+ EBUG_ON(iter->locks_want < new_locks_want);
- linked->locks_want = new_locks_want;
+ iter->locks_want = new_locks_want;
- while (linked->nodes_locked &&
- (l = __fls(linked->nodes_locked)) >= linked->locks_want) {
- if (l > linked->level) {
- btree_node_unlock(linked, l);
- } else {
- if (btree_node_intent_locked(linked, l)) {
- six_lock_downgrade(&linked->l[l].b->lock);
- linked->nodes_intent_locked ^= 1 << l;
- }
- break;
+ while (iter->nodes_locked &&
+ (l = __fls(iter->nodes_locked)) >= iter->locks_want) {
+ if (l > iter->level) {
+ btree_node_unlock(iter, l);
+ } else {
+ if (btree_node_intent_locked(iter, l)) {
+ six_lock_downgrade(&iter->l[l].b->c.lock);
+ iter->nodes_intent_locked ^= 1 << l;
}
+ break;
}
}
bch2_btree_trans_verify_locks(iter->trans);
}
-int bch2_btree_iter_unlock(struct btree_iter *iter)
+void bch2_trans_downgrade(struct btree_trans *trans)
{
- struct btree_iter *linked;
+ struct btree_iter *iter;
- trans_for_each_iter(iter->trans, linked)
- __bch2_btree_iter_unlock(linked);
+ trans_for_each_iter(trans, iter)
+ bch2_btree_iter_downgrade(iter);
+}
- return btree_iter_err(iter);
+/* Btree transaction locking: */
+
+static inline bool btree_iter_should_be_locked(struct btree_trans *trans,
+ struct btree_iter *iter)
+{
+ return (iter->flags & BTREE_ITER_KEEP_UNTIL_COMMIT) ||
+ iter->should_be_locked;
}
-bool bch2_btree_trans_relock(struct btree_trans *trans)
+bool bch2_trans_relock(struct btree_trans *trans)
{
struct btree_iter *iter;
- bool ret = true;
trans_for_each_iter(trans, iter)
- ret &= bch2_btree_iter_relock(iter);
-
- return ret;
+ if (!bch2_btree_iter_relock(iter, _RET_IP_) &&
+ btree_iter_should_be_locked(trans, iter)) {
+ trace_trans_restart_relock(trans->ip, _RET_IP_,
+ iter->btree_id, &iter->real_pos);
+ return false;
+ }
+ return true;
}
-void bch2_btree_trans_unlock(struct btree_trans *trans)
+void bch2_trans_unlock(struct btree_trans *trans)
{
struct btree_iter *iter;
__bch2_btree_iter_unlock(iter);
}
-/* Btree transaction locking: */
-
/* Btree iterator: */
#ifdef CONFIG_BCACHEFS_DEBUG
-static void __bch2_btree_iter_verify(struct btree_iter *iter,
- struct btree *b)
+static void bch2_btree_iter_verify_cached(struct btree_iter *iter)
{
- struct btree_iter_level *l = &iter->l[b->level];
- struct btree_node_iter tmp = l->iter;
- struct bkey_packed *k;
+ struct bkey_cached *ck;
+ bool locked = btree_node_locked(iter, 0);
+
+ if (!bch2_btree_node_relock(iter, 0))
+ return;
+
+ ck = (void *) iter->l[0].b;
+ BUG_ON(ck->key.btree_id != iter->btree_id ||
+ bkey_cmp(ck->key.pos, iter->pos));
+
+ if (!locked)
+ btree_node_unlock(iter, 0);
+}
- if (!debug_check_iterators(iter->trans->c))
+static void bch2_btree_iter_verify_level(struct btree_iter *iter,
+ unsigned level)
+{
+ struct btree_iter_level *l;
+ struct btree_node_iter tmp;
+ bool locked;
+ struct bkey_packed *p, *k;
+ char buf1[100], buf2[100], buf3[100];
+ const char *msg;
+
+ if (!bch2_debug_check_iterators)
+ return;
+
+ l = &iter->l[level];
+ tmp = l->iter;
+ locked = btree_node_locked(iter, level);
+
+ if (btree_iter_type(iter) == BTREE_ITER_CACHED) {
+ if (!level)
+ bch2_btree_iter_verify_cached(iter);
+ return;
+ }
+
+ BUG_ON(iter->level < iter->min_depth);
+
+ if (!btree_iter_node(iter, level))
return;
- if (iter->uptodate > BTREE_ITER_NEED_PEEK)
+ if (!bch2_btree_node_relock(iter, level))
return;
- bch2_btree_node_iter_verify(&l->iter, b);
+ BUG_ON(!btree_iter_pos_in_node(iter, l->b));
+
+ /*
+ * node iterators don't use leaf node iterator:
+ */
+ if (btree_iter_type(iter) == BTREE_ITER_NODES &&
+ level <= iter->min_depth)
+ goto unlock;
+
+ bch2_btree_node_iter_verify(&l->iter, l->b);
/*
* For interior nodes, the iterator will have skipped past
* For extents, the iterator may have skipped past deleted keys (but not
* whiteouts)
*/
- k = b->level || iter->flags & BTREE_ITER_IS_EXTENTS
- ? bch2_btree_node_iter_prev_filter(&tmp, b, KEY_TYPE_discard)
- : bch2_btree_node_iter_prev_all(&tmp, b);
- if (k && btree_iter_pos_cmp(iter, b, k) > 0) {
- char buf[100];
- struct bkey uk = bkey_unpack_key(b, k);
+ p = level || btree_node_type_is_extents(iter->btree_id)
+ ? bch2_btree_node_iter_prev(&tmp, l->b)
+ : bch2_btree_node_iter_prev_all(&tmp, l->b);
+ k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
- bch2_bkey_to_text(&PBUF(buf), &uk);
- panic("prev key should be before iter pos:\n%s\n%llu:%llu\n",
- buf, iter->pos.inode, iter->pos.offset);
+ if (p && bkey_iter_pos_cmp(l->b, p, &iter->real_pos) >= 0) {
+ msg = "before";
+ goto err;
}
- k = bch2_btree_node_iter_peek_all(&l->iter, b);
- if (k && btree_iter_pos_cmp(iter, b, k) < 0) {
- char buf[100];
- struct bkey uk = bkey_unpack_key(b, k);
+ if (k && bkey_iter_pos_cmp(l->b, k, &iter->real_pos) < 0) {
+ msg = "after";
+ goto err;
+ }
+unlock:
+ if (!locked)
+ btree_node_unlock(iter, level);
+ return;
+err:
+ strcpy(buf2, "(none)");
+ strcpy(buf3, "(none)");
- bch2_bkey_to_text(&PBUF(buf), &uk);
- panic("iter should be after current key:\n"
- "iter pos %llu:%llu\n"
- "cur key %s\n",
- iter->pos.inode, iter->pos.offset, buf);
+ bch2_bpos_to_text(&PBUF(buf1), iter->real_pos);
+
+ if (p) {
+ struct bkey uk = bkey_unpack_key(l->b, p);
+ bch2_bkey_to_text(&PBUF(buf2), &uk);
+ }
+
+ if (k) {
+ struct bkey uk = bkey_unpack_key(l->b, k);
+ bch2_bkey_to_text(&PBUF(buf3), &uk);
}
- BUG_ON(iter->uptodate == BTREE_ITER_UPTODATE &&
- (iter->flags & BTREE_ITER_TYPE) == BTREE_ITER_KEYS &&
- !bkey_whiteout(&iter->k) &&
- bch2_btree_node_iter_end(&l->iter));
+ panic("iterator should be %s key at level %u:\n"
+ "iter pos %s\n"
+ "prev key %s\n"
+ "cur key %s\n",
+ msg, level, buf1, buf2, buf3);
}
-void bch2_btree_iter_verify(struct btree_iter *iter, struct btree *b)
+static void bch2_btree_iter_verify(struct btree_iter *iter)
{
- struct btree_iter *linked;
+ enum btree_iter_type type = btree_iter_type(iter);
+ unsigned i;
+
+ EBUG_ON(iter->btree_id >= BTREE_ID_NR);
+
+ BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
+ iter->pos.snapshot != iter->snapshot);
+
+ BUG_ON((iter->flags & BTREE_ITER_IS_EXTENTS) &&
+ (iter->flags & BTREE_ITER_ALL_SNAPSHOTS));
+
+ BUG_ON(type == BTREE_ITER_NODES &&
+ !(iter->flags & BTREE_ITER_ALL_SNAPSHOTS));
+
+ BUG_ON(type != BTREE_ITER_NODES &&
+ (iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
+ !btree_type_has_snapshots(iter->btree_id));
+
+ bch2_btree_iter_verify_locks(iter);
- if (!debug_check_iterators(iter->trans->c))
+ for (i = 0; i < BTREE_MAX_DEPTH; i++)
+ bch2_btree_iter_verify_level(iter, i);
+}
+
+static void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter)
+{
+ enum btree_iter_type type = btree_iter_type(iter);
+
+ BUG_ON(!(iter->flags & BTREE_ITER_ALL_SNAPSHOTS) &&
+ iter->pos.snapshot != iter->snapshot);
+
+ BUG_ON((type == BTREE_ITER_KEYS ||
+ type == BTREE_ITER_CACHED) &&
+ (bkey_cmp(iter->pos, bkey_start_pos(&iter->k)) < 0 ||
+ bkey_cmp(iter->pos, iter->k.p) > 0));
+}
+
+void bch2_btree_trans_verify_iters(struct btree_trans *trans, struct btree *b)
+{
+ struct btree_iter *iter;
+
+ if (!bch2_debug_check_iterators)
return;
- trans_for_each_iter_with_node(iter->trans, b, linked)
- __bch2_btree_iter_verify(linked, b);
+ trans_for_each_iter_with_node(trans, b, iter)
+ bch2_btree_iter_verify_level(iter, b->c.level);
}
#else
-static inline void __bch2_btree_iter_verify(struct btree_iter *iter,
- struct btree *b) {}
+static inline void bch2_btree_iter_verify_level(struct btree_iter *iter, unsigned l) {}
+static inline void bch2_btree_iter_verify(struct btree_iter *iter) {}
+static inline void bch2_btree_iter_verify_entry_exit(struct btree_iter *iter) {}
#endif
+static void btree_node_iter_set_set_pos(struct btree_node_iter *iter,
+ struct btree *b,
+ struct bset_tree *t,
+ struct bkey_packed *k)
+{
+ struct btree_node_iter_set *set;
+
+ btree_node_iter_for_each(iter, set)
+ if (set->end == t->end_offset) {
+ set->k = __btree_node_key_to_offset(b, k);
+ bch2_btree_node_iter_sort(iter, b);
+ return;
+ }
+
+ bch2_btree_node_iter_push(iter, b, k, btree_bkey_last(b, t));
+}
+
+static void __bch2_btree_iter_fix_key_modified(struct btree_iter *iter,
+ struct btree *b,
+ struct bkey_packed *where)
+{
+ struct btree_iter_level *l = &iter->l[b->c.level];
+
+ if (where != bch2_btree_node_iter_peek_all(&l->iter, l->b))
+ return;
+
+ if (bkey_iter_pos_cmp(l->b, where, &iter->real_pos) < 0)
+ bch2_btree_node_iter_advance(&l->iter, l->b);
+
+ btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
+}
+
+void bch2_btree_iter_fix_key_modified(struct btree_iter *iter,
+ struct btree *b,
+ struct bkey_packed *where)
+{
+ struct btree_iter *linked;
+
+ trans_for_each_iter_with_node(iter->trans, b, linked) {
+ __bch2_btree_iter_fix_key_modified(linked, b, where);
+ bch2_btree_iter_verify_level(linked, b->c.level);
+ }
+}
+
static void __bch2_btree_node_iter_fix(struct btree_iter *iter,
struct btree *b,
struct btree_node_iter *node_iter,
unsigned offset = __btree_node_key_to_offset(b, where);
int shift = new_u64s - clobber_u64s;
unsigned old_end = t->end_offset - shift;
+ unsigned orig_iter_pos = node_iter->data[0].k;
+ bool iter_current_key_modified =
+ orig_iter_pos >= offset &&
+ orig_iter_pos <= offset + clobber_u64s;
btree_node_iter_for_each(node_iter, set)
if (set->end == old_end)
/* didn't find the bset in the iterator - might have to readd it: */
if (new_u64s &&
- btree_iter_pos_cmp(iter, b, where) > 0) {
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
-
+ bkey_iter_pos_cmp(b, where, &iter->real_pos) >= 0) {
bch2_btree_node_iter_push(node_iter, b, where, end);
-
- if (!b->level &&
- node_iter == &iter->l[0].iter)
- bkey_disassemble(b,
- bch2_btree_node_iter_peek_all(node_iter, b),
- &iter->k);
+ goto fixup_done;
+ } else {
+ /* Iterator is after key that changed */
+ return;
}
- return;
found:
set->end = t->end_offset;
return;
if (new_u64s &&
- btree_iter_pos_cmp(iter, b, where) > 0) {
+ bkey_iter_pos_cmp(b, where, &iter->real_pos) >= 0) {
set->k = offset;
} else if (set->k < offset + clobber_u64s) {
set->k = offset + new_u64s;
if (set->k == set->end)
bch2_btree_node_iter_set_drop(node_iter, set);
} else {
+ /* Iterator is after key that changed */
set->k = (int) set->k + shift;
- goto iter_current_key_not_modified;
+ return;
}
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
-
bch2_btree_node_iter_sort(node_iter, b);
- if (!b->level && node_iter == &iter->l[0].iter) {
- /*
- * not legal to call bkey_debugcheck() here, because we're
- * called midway through the update path after update has been
- * marked but before deletes have actually happened:
- */
-#if 0
- __btree_iter_peek_all(iter, &iter->l[0], &iter->k);
-#endif
- struct btree_iter_level *l = &iter->l[0];
- struct bkey_packed *k =
- bch2_btree_node_iter_peek_all(&l->iter, l->b);
-
- if (unlikely(!k))
- iter->k.type = KEY_TYPE_deleted;
- else
- bkey_disassemble(l->b, k, &iter->k);
- }
-iter_current_key_not_modified:
+fixup_done:
+ if (node_iter->data[0].k != orig_iter_pos)
+ iter_current_key_modified = true;
/*
- * Interior nodes are special because iterators for interior nodes don't
- * obey the usual invariants regarding the iterator position:
- *
- * We may have whiteouts that compare greater than the iterator
- * position, and logically should be in the iterator, but that we
- * skipped past to find the first live key greater than the iterator
- * position. This becomes an issue when we insert a new key that is
- * greater than the current iterator position, but smaller than the
- * whiteouts we've already skipped past - this happens in the course of
- * a btree split.
- *
- * We have to rewind the iterator past to before those whiteouts here,
- * else bkey_node_iter_prev() is not going to work and who knows what
- * else would happen. And we have to do it manually, because here we've
- * already done the insert and the iterator is currently inconsistent:
- *
- * We've got multiple competing invariants, here - we have to be careful
- * about rewinding iterators for interior nodes, because they should
- * always point to the key for the child node the btree iterator points
- * to.
+ * When a new key is added, and the node iterator now points to that
+ * key, the iterator might have skipped past deleted keys that should
+ * come after the key the iterator now points to. We have to rewind to
+ * before those deleted keys - otherwise
+ * bch2_btree_node_iter_prev_all() breaks:
*/
- if (b->level && new_u64s &&
- btree_iter_pos_cmp(iter, b, where) > 0) {
+ if (!bch2_btree_node_iter_end(node_iter) &&
+ iter_current_key_modified &&
+ (b->c.level ||
+ btree_node_type_is_extents(iter->btree_id))) {
struct bset_tree *t;
- struct bkey_packed *k;
+ struct bkey_packed *k, *k2, *p;
+
+ k = bch2_btree_node_iter_peek_all(node_iter, b);
for_each_bset(b, t) {
- if (bch2_bkey_to_bset(b, where) == t)
+ bool set_pos = false;
+
+ if (node_iter->data[0].end == t->end_offset)
continue;
- k = bch2_bkey_prev_all(b, t,
- bch2_btree_node_iter_bset_pos(node_iter, b, t));
- if (k &&
- bkey_iter_cmp(b, k, where) > 0) {
- struct btree_node_iter_set *set;
- unsigned offset =
- __btree_node_key_to_offset(b, bkey_next(k));
-
- btree_node_iter_for_each(node_iter, set)
- if (set->k == offset) {
- set->k = __btree_node_key_to_offset(b, k);
- bch2_btree_node_iter_sort(node_iter, b);
- goto next_bset;
- }
-
- bch2_btree_node_iter_push(node_iter, b, k,
- btree_bkey_last(b, t));
+ k2 = bch2_btree_node_iter_bset_pos(node_iter, b, t);
+
+ while ((p = bch2_bkey_prev_all(b, t, k2)) &&
+ bkey_iter_cmp(b, k, p) < 0) {
+ k2 = p;
+ set_pos = true;
}
-next_bset:
- t = t;
+
+ if (set_pos)
+ btree_node_iter_set_set_pos(node_iter,
+ b, t, k2);
}
}
+
+ if (!b->c.level &&
+ node_iter == &iter->l[0].iter &&
+ iter_current_key_modified)
+ btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
}
void bch2_btree_node_iter_fix(struct btree_iter *iter,
struct bset_tree *t = bch2_bkey_to_bset(b, where);
struct btree_iter *linked;
- if (node_iter != &iter->l[b->level].iter)
+ if (node_iter != &iter->l[b->c.level].iter) {
__bch2_btree_node_iter_fix(iter, b, node_iter, t,
- where, clobber_u64s, new_u64s);
+ where, clobber_u64s, new_u64s);
- trans_for_each_iter_with_node(iter->trans, b, linked)
+ if (bch2_debug_check_iterators)
+ bch2_btree_node_iter_verify(node_iter, b);
+ }
+
+ trans_for_each_iter_with_node(iter->trans, b, linked) {
__bch2_btree_node_iter_fix(linked, b,
- &linked->l[b->level].iter, t,
- where, clobber_u64s, new_u64s);
+ &linked->l[b->c.level].iter, t,
+ where, clobber_u64s, new_u64s);
+ bch2_btree_iter_verify_level(linked, b->c.level);
+ }
}
static inline struct bkey_s_c __btree_iter_unpack(struct btree_iter *iter,
ret = bkey_disassemble(l->b, k, u);
- if (debug_check_bkeys(iter->trans->c))
+ /*
+ * XXX: bch2_btree_bset_insert_key() generates invalid keys when we
+ * overwrite extents - it sets k->type = KEY_TYPE_deleted on the key
+ * being overwritten but doesn't change k->size. But this is ok, because
+ * those keys are never written out, we just have to avoid a spurious
+ * assertion here:
+ */
+ if (bch2_debug_check_bkeys && !bkey_deleted(ret.k))
bch2_bkey_debugcheck(iter->trans->c, l->b, ret);
return ret;
}
/* peek_all() doesn't skip deleted keys */
-static inline struct bkey_s_c __btree_iter_peek_all(struct btree_iter *iter,
- struct btree_iter_level *l,
- struct bkey *u)
+static inline struct bkey_s_c btree_iter_level_peek_all(struct btree_iter *iter,
+ struct btree_iter_level *l)
{
- return __btree_iter_unpack(iter, l, u,
+ return __btree_iter_unpack(iter, l, &iter->k,
bch2_btree_node_iter_peek_all(&l->iter, l->b));
}
-static inline struct bkey_s_c __btree_iter_peek(struct btree_iter *iter,
- struct btree_iter_level *l)
+static inline struct bkey_s_c btree_iter_level_peek(struct btree_iter *iter,
+ struct btree_iter_level *l)
{
- return __btree_iter_unpack(iter, l, &iter->k,
+ struct bkey_s_c k = __btree_iter_unpack(iter, l, &iter->k,
bch2_btree_node_iter_peek(&l->iter, l->b));
+
+ iter->real_pos = k.k ? k.k->p : l->b->key.k.p;
+ return k;
+}
+
+static inline struct bkey_s_c btree_iter_level_prev(struct btree_iter *iter,
+ struct btree_iter_level *l)
+{
+ struct bkey_s_c k = __btree_iter_unpack(iter, l, &iter->k,
+ bch2_btree_node_iter_prev(&l->iter, l->b));
+
+ iter->real_pos = k.k ? k.k->p : l->b->data->min_key;
+ return k;
}
static inline bool btree_iter_advance_to_pos(struct btree_iter *iter,
int nr_advanced = 0;
while ((k = bch2_btree_node_iter_peek_all(&l->iter, l->b)) &&
- btree_iter_pos_cmp(iter, l->b, k) < 0) {
+ bkey_iter_pos_cmp(l->b, k, &iter->real_pos) < 0) {
if (max_advance > 0 && nr_advanced >= max_advance)
return false;
if (!IS_ENABLED(CONFIG_BCACHEFS_DEBUG))
return;
- plevel = b->level + 1;
+ plevel = b->c.level + 1;
if (!btree_iter_node(iter, plevel))
return;
if (!k ||
bkey_deleted(k) ||
bkey_cmp_left_packed(l->b, k, &b->key.k.p)) {
- char buf[100];
+ char buf1[100];
+ char buf2[100];
+ char buf3[100];
+ char buf4[100];
struct bkey uk = bkey_unpack_key(b, k);
- bch2_bkey_to_text(&PBUF(buf), &uk);
- panic("parent iter doesn't point to new node:\n%s\n%llu:%llu\n",
- buf, b->key.k.p.inode, b->key.k.p.offset);
+ bch2_dump_btree_node(iter->trans->c, l->b);
+ bch2_bpos_to_text(&PBUF(buf1), iter->real_pos);
+ bch2_bkey_to_text(&PBUF(buf2), &uk);
+ bch2_bpos_to_text(&PBUF(buf3), b->data->min_key);
+ bch2_bpos_to_text(&PBUF(buf3), b->data->max_key);
+ panic("parent iter doesn't point to new node:\n"
+ "iter pos %s %s\n"
+ "iter key %s\n"
+ "new node %s-%s\n",
+ bch2_btree_ids[iter->btree_id], buf1,
+ buf2, buf3, buf4);
}
if (!parent_locked)
- btree_node_unlock(iter, b->level + 1);
-}
-
-static inline bool btree_iter_pos_after_node(struct btree_iter *iter,
- struct btree *b)
-{
- return __btree_iter_pos_cmp(iter, NULL,
- bkey_to_packed(&b->key), true) < 0;
-}
-
-static inline bool btree_iter_pos_in_node(struct btree_iter *iter,
- struct btree *b)
-{
- return iter->btree_id == b->btree_id &&
- bkey_cmp(iter->pos, b->data->min_key) >= 0 &&
- !btree_iter_pos_after_node(iter, b);
+ btree_node_unlock(iter, b->c.level + 1);
}
static inline void __btree_iter_init(struct btree_iter *iter,
{
struct btree_iter_level *l = &iter->l[level];
- bch2_btree_node_iter_init(&l->iter, l->b, &iter->pos);
+ bch2_btree_node_iter_init(&l->iter, l->b, &iter->real_pos);
- if (iter->flags & BTREE_ITER_IS_EXTENTS)
- btree_iter_advance_to_pos(iter, l, -1);
-
- /* Skip to first non whiteout: */
+ /*
+ * Iterators to interior nodes should always be pointed at the first non
+ * whiteout:
+ */
if (level)
bch2_btree_node_iter_peek(&l->iter, l->b);
static inline void btree_iter_node_set(struct btree_iter *iter,
struct btree *b)
{
+ BUG_ON(btree_iter_type(iter) == BTREE_ITER_CACHED);
+
btree_iter_verify_new_node(iter, b);
EBUG_ON(!btree_iter_pos_in_node(iter, b));
- EBUG_ON(b->lock.state.seq & 1);
+ EBUG_ON(b->c.lock.state.seq & 1);
- iter->l[b->level].lock_seq = b->lock.state.seq;
- iter->l[b->level].b = b;
- __btree_iter_init(iter, b->level);
+ iter->l[b->c.level].lock_seq = b->c.lock.state.seq;
+ iter->l[b->c.level].b = b;
+ __btree_iter_init(iter, b->c.level);
}
/*
struct btree_iter *linked;
trans_for_each_iter(iter->trans, linked)
- if (btree_iter_pos_in_node(linked, b)) {
+ if (btree_iter_type(linked) != BTREE_ITER_CACHED &&
+ btree_iter_pos_in_node(linked, b)) {
/*
* bch2_btree_iter_node_drop() has already been called -
* the old node we're replacing has already been
* unlocked and the pointer invalidated
*/
- BUG_ON(btree_node_locked(linked, b->level));
+ BUG_ON(btree_node_locked(linked, b->c.level));
- t = btree_lock_want(linked, b->level);
+ t = btree_lock_want(linked, b->c.level);
if (t != BTREE_NODE_UNLOCKED) {
- six_lock_increment(&b->lock, t);
- mark_btree_node_locked(linked, b->level, t);
+ six_lock_increment(&b->c.lock, t);
+ mark_btree_node_locked(linked, b->c.level, t);
}
btree_iter_node_set(linked, b);
}
-
- six_unlock_intent(&b->lock);
}
void bch2_btree_iter_node_drop(struct btree_iter *iter, struct btree *b)
{
struct btree_iter *linked;
- unsigned level = b->level;
+ unsigned level = b->c.level;
trans_for_each_iter(iter->trans, linked)
if (linked->l[level].b == b) {
- __btree_node_unlock(linked, level);
- linked->l[level].b = BTREE_ITER_NOT_END;
+ btree_node_unlock(linked, level);
+ linked->l[level].b = BTREE_ITER_NO_NODE_DROP;
}
}
struct btree_iter *linked;
trans_for_each_iter_with_node(iter->trans, b, linked)
- __btree_iter_init(linked, b->level);
+ __btree_iter_init(linked, b->c.level);
+}
+
+static int lock_root_check_fn(struct six_lock *lock, void *p)
+{
+ struct btree *b = container_of(lock, struct btree, c.lock);
+ struct btree **rootp = p;
+
+ return b == *rootp ? 0 : -1;
}
static inline int btree_iter_lock_root(struct btree_iter *iter,
- unsigned depth_want)
+ unsigned depth_want,
+ unsigned long trace_ip)
{
struct bch_fs *c = iter->trans->c;
- struct btree *b;
+ struct btree *b, **rootp = &c->btree_roots[iter->btree_id].b;
enum six_lock_type lock_type;
unsigned i;
EBUG_ON(iter->nodes_locked);
while (1) {
- b = READ_ONCE(c->btree_roots[iter->btree_id].b);
- iter->level = READ_ONCE(b->level);
+ b = READ_ONCE(*rootp);
+ iter->level = READ_ONCE(b->c.level);
if (unlikely(iter->level < depth_want)) {
/*
* that depth
*/
iter->level = depth_want;
- iter->l[iter->level].b = NULL;
+ for (i = iter->level; i < BTREE_MAX_DEPTH; i++)
+ iter->l[i].b = NULL;
return 1;
}
lock_type = __btree_lock_want(iter, iter->level);
if (unlikely(!btree_node_lock(b, POS_MAX, iter->level,
- iter, lock_type, true)))
+ iter, lock_type,
+ lock_root_check_fn, rootp,
+ trace_ip)))
return -EINTR;
- if (likely(b == c->btree_roots[iter->btree_id].b &&
- b->level == iter->level &&
+ if (likely(b == READ_ONCE(*rootp) &&
+ b->c.level == iter->level &&
!race_fault())) {
for (i = 0; i < iter->level; i++)
- iter->l[i].b = BTREE_ITER_NOT_END;
+ iter->l[i].b = BTREE_ITER_NO_NODE_LOCK_ROOT;
iter->l[iter->level].b = b;
+ for (i = iter->level + 1; i < BTREE_MAX_DEPTH; i++)
+ iter->l[i].b = NULL;
mark_btree_node_locked(iter, iter->level, lock_type);
btree_iter_node_set(iter, b);
return 0;
-
}
- six_unlock_type(&b->lock, lock_type);
+ six_unlock_type(&b->c.lock, lock_type);
}
}
struct btree_iter_level *l = &iter->l[iter->level];
struct btree_node_iter node_iter = l->iter;
struct bkey_packed *k;
- BKEY_PADDED(k) tmp;
+ struct bkey_buf tmp;
unsigned nr = test_bit(BCH_FS_STARTED, &c->flags)
? (iter->level > 1 ? 0 : 2)
: (iter->level > 1 ? 1 : 16);
bool was_locked = btree_node_locked(iter, iter->level);
+ bch2_bkey_buf_init(&tmp);
+
while (nr) {
if (!bch2_btree_node_relock(iter, iter->level))
- return;
+ break;
bch2_btree_node_iter_advance(&node_iter, l->b);
k = bch2_btree_node_iter_peek(&node_iter, l->b);
if (!k)
break;
- bch2_bkey_unpack(l->b, &tmp.k, k);
- bch2_btree_node_prefetch(c, iter, &tmp.k, iter->level - 1);
+ bch2_bkey_buf_unpack(&tmp, c, l->b, k);
+ bch2_btree_node_prefetch(c, iter, tmp.k, iter->btree_id,
+ iter->level - 1);
}
if (!was_locked)
btree_node_unlock(iter, iter->level);
+
+ bch2_bkey_buf_exit(&tmp, c);
+}
+
+static noinline void btree_node_mem_ptr_set(struct btree_iter *iter,
+ unsigned plevel, struct btree *b)
+{
+ struct btree_iter_level *l = &iter->l[plevel];
+ bool locked = btree_node_locked(iter, plevel);
+ struct bkey_packed *k;
+ struct bch_btree_ptr_v2 *bp;
+
+ if (!bch2_btree_node_relock(iter, plevel))
+ return;
+
+ k = bch2_btree_node_iter_peek_all(&l->iter, l->b);
+ BUG_ON(k->type != KEY_TYPE_btree_ptr_v2);
+
+ bp = (void *) bkeyp_val(&l->b->format, k);
+ bp->mem_ptr = (unsigned long)b;
+
+ if (!locked)
+ btree_node_unlock(iter, plevel);
}
-static inline int btree_iter_down(struct btree_iter *iter)
+static __always_inline int btree_iter_down(struct btree_iter *iter,
+ unsigned long trace_ip)
{
struct bch_fs *c = iter->trans->c;
struct btree_iter_level *l = &iter->l[iter->level];
struct btree *b;
unsigned level = iter->level - 1;
enum six_lock_type lock_type = __btree_lock_want(iter, level);
- BKEY_PADDED(k) tmp;
+ struct bkey_buf tmp;
+ int ret;
- BUG_ON(!btree_node_locked(iter, iter->level));
+ EBUG_ON(!btree_node_locked(iter, iter->level));
- bch2_bkey_unpack(l->b, &tmp.k,
+ bch2_bkey_buf_init(&tmp);
+ bch2_bkey_buf_unpack(&tmp, c, l->b,
bch2_btree_node_iter_peek(&l->iter, l->b));
- b = bch2_btree_node_get(c, iter, &tmp.k, level, lock_type, true);
- if (unlikely(IS_ERR(b)))
- return PTR_ERR(b);
+ b = bch2_btree_node_get(c, iter, tmp.k, level, lock_type, trace_ip);
+ ret = PTR_ERR_OR_ZERO(b);
+ if (unlikely(ret))
+ goto err;
mark_btree_node_locked(iter, level, lock_type);
btree_iter_node_set(iter, b);
+ if (tmp.k->k.type == KEY_TYPE_btree_ptr_v2 &&
+ unlikely(b != btree_node_mem_ptr(tmp.k)))
+ btree_node_mem_ptr_set(iter, level + 1, b);
+
if (iter->flags & BTREE_ITER_PREFETCH)
btree_iter_prefetch(iter);
+ if (btree_node_read_locked(iter, level + 1))
+ btree_node_unlock(iter, level + 1);
iter->level = level;
- return 0;
-}
-
-static void btree_iter_up(struct btree_iter *iter)
-{
- btree_node_unlock(iter, iter->level++);
+ bch2_btree_iter_verify_locks(iter);
+err:
+ bch2_bkey_buf_exit(&tmp, c);
+ return ret;
}
-int __must_check __bch2_btree_iter_traverse(struct btree_iter *);
+static int btree_iter_traverse_one(struct btree_iter *, unsigned long);
-static int __btree_iter_traverse_all(struct btree_trans *trans,
- struct btree_iter *iter, int ret)
+static int __btree_iter_traverse_all(struct btree_trans *trans, int ret,
+ unsigned long trace_ip)
{
struct bch_fs *c = trans->c;
+ struct btree_iter *iter;
u8 sorted[BTREE_ITER_MAX];
- unsigned i, nr_sorted = 0;
+ int i, nr_sorted = 0;
+ bool relock_fail;
- trans_for_each_iter(trans, iter)
- sorted[nr_sorted++] = iter - trans->iters;
+ if (trans->in_traverse_all)
+ return -EINTR;
+
+ trans->in_traverse_all = true;
+retry_all:
+ nr_sorted = 0;
+ relock_fail = false;
+
+ trans_for_each_iter(trans, iter) {
+ if (!bch2_btree_iter_relock(iter, _THIS_IP_))
+ relock_fail = true;
+ sorted[nr_sorted++] = iter->idx;
+ }
+
+ if (!relock_fail) {
+ trans->in_traverse_all = false;
+ return 0;
+ }
#define btree_iter_cmp_by_idx(_l, _r) \
- btree_iter_cmp(&trans->iters[_l], &trans->iters[_r])
+ btree_iter_lock_cmp(&trans->iters[_l], &trans->iters[_r])
bubble_sort(sorted, nr_sorted, btree_iter_cmp_by_idx);
#undef btree_iter_cmp_by_idx
-retry_all:
- bch2_btree_trans_unlock(trans);
+ for (i = nr_sorted - 2; i >= 0; --i) {
+ struct btree_iter *iter1 = trans->iters + sorted[i];
+ struct btree_iter *iter2 = trans->iters + sorted[i + 1];
+
+ if (iter1->btree_id == iter2->btree_id &&
+ iter1->locks_want < iter2->locks_want)
+ __bch2_btree_iter_upgrade(iter1, iter2->locks_want);
+ else if (!iter1->locks_want && iter2->locks_want)
+ __bch2_btree_iter_upgrade(iter1, 1);
+ }
+
+ bch2_trans_unlock(trans);
+ cond_resched();
if (unlikely(ret == -ENOMEM)) {
struct closure cl;
if (unlikely(ret == -EIO)) {
trans->error = true;
- iter->flags |= BTREE_ITER_ERROR;
- iter->l[iter->level].b = BTREE_ITER_NOT_END;
goto out;
}
/* Now, redo traversals in correct order: */
for (i = 0; i < nr_sorted; i++) {
- iter = &trans->iters[sorted[i]];
+ unsigned idx = sorted[i];
- do {
- ret = __bch2_btree_iter_traverse(iter);
- } while (ret == -EINTR);
+ /*
+ * sucessfully traversing one iterator can cause another to be
+ * unlinked, in btree_key_cache_fill()
+ */
+ if (!(trans->iters_linked & (1ULL << idx)))
+ continue;
+ ret = btree_iter_traverse_one(&trans->iters[idx], _THIS_IP_);
if (ret)
goto retry_all;
}
- ret = hweight64(trans->iters_live) > 1 ? -EINTR : 0;
+ if (hweight64(trans->iters_live) > 1)
+ ret = -EINTR;
+ else
+ trans_for_each_iter(trans, iter)
+ if (iter->flags & BTREE_ITER_KEEP_UNTIL_COMMIT) {
+ ret = -EINTR;
+ break;
+ }
out:
bch2_btree_cache_cannibalize_unlock(c);
+
+ trans->in_traverse_all = false;
+
+ trace_trans_traverse_all(trans->ip, trace_ip);
return ret;
}
int bch2_btree_iter_traverse_all(struct btree_trans *trans)
{
- return __btree_iter_traverse_all(trans, NULL, 0);
+ return __btree_iter_traverse_all(trans, 0, _RET_IP_);
}
-static unsigned btree_iter_up_until_locked(struct btree_iter *iter,
- bool check_pos)
+static inline bool btree_iter_good_node(struct btree_iter *iter,
+ unsigned l, int check_pos)
+{
+ if (!is_btree_node(iter, l) ||
+ !bch2_btree_node_relock(iter, l))
+ return false;
+
+ if (check_pos < 0 && btree_iter_pos_before_node(iter, iter->l[l].b))
+ return false;
+ if (check_pos > 0 && btree_iter_pos_after_node(iter, iter->l[l].b))
+ return false;
+ return true;
+}
+
+static inline unsigned btree_iter_up_until_good_node(struct btree_iter *iter,
+ int check_pos)
{
unsigned l = iter->level;
while (btree_iter_node(iter, l) &&
- !(is_btree_node(iter, l) &&
- bch2_btree_node_relock(iter, l) &&
- (!check_pos ||
- btree_iter_pos_in_node(iter, iter->l[l].b)))) {
+ !btree_iter_good_node(iter, l, check_pos)) {
btree_node_unlock(iter, l);
- iter->l[l].b = BTREE_ITER_NOT_END;
+ iter->l[l].b = BTREE_ITER_NO_NODE_UP;
l++;
}
* Returns 0 on success, -EIO on error (error reading in a btree node).
*
* On error, caller (peek_node()/peek_key()) must return NULL; the error is
- * stashed in the iterator and returned from bch2_btree_iter_unlock().
+ * stashed in the iterator and returned from bch2_trans_exit().
*/
-int __must_check __bch2_btree_iter_traverse(struct btree_iter *iter)
+static int btree_iter_traverse_one(struct btree_iter *iter,
+ unsigned long trace_ip)
{
unsigned depth_want = iter->level;
-
- if (unlikely(iter->level >= BTREE_MAX_DEPTH))
- return 0;
-
- if (bch2_btree_iter_relock(iter))
- return 0;
+ int ret = 0;
/*
- * XXX: correctly using BTREE_ITER_UPTODATE should make using check_pos
- * here unnecessary
+ * if we need interior nodes locked, call btree_iter_relock() to make
+ * sure we walk back up enough that we lock them:
*/
- iter->level = btree_iter_up_until_locked(iter, true);
+ if (iter->uptodate == BTREE_ITER_NEED_RELOCK ||
+ iter->locks_want > 1)
+ bch2_btree_iter_relock(iter, _THIS_IP_);
- /*
- * If we've got a btree node locked (i.e. we aren't about to relock the
- * root) - advance its node iterator if necessary:
- *
- * XXX correctly using BTREE_ITER_UPTODATE should make this unnecessary
- */
- if (btree_iter_node(iter, iter->level))
- btree_iter_advance_to_pos(iter, &iter->l[iter->level], -1);
+ if (btree_iter_type(iter) == BTREE_ITER_CACHED) {
+ ret = bch2_btree_iter_traverse_cached(iter);
+ goto out;
+ }
+
+ if (iter->uptodate < BTREE_ITER_NEED_RELOCK)
+ goto out;
+
+ if (unlikely(iter->level >= BTREE_MAX_DEPTH))
+ goto out;
+
+ iter->level = btree_iter_up_until_good_node(iter, 0);
/*
* Note: iter->nodes[iter->level] may be temporarily NULL here - that
* btree_iter_lock_root() comes next and that it can't fail
*/
while (iter->level > depth_want) {
- int ret = btree_iter_node(iter, iter->level)
- ? btree_iter_down(iter)
- : btree_iter_lock_root(iter, depth_want);
+ ret = btree_iter_node(iter, iter->level)
+ ? btree_iter_down(iter, trace_ip)
+ : btree_iter_lock_root(iter, depth_want, trace_ip);
if (unlikely(ret)) {
- if (ret == 1)
- return 0;
+ if (ret == 1) {
+ /*
+ * Got to the end of the btree (in
+ * BTREE_ITER_NODES mode)
+ */
+ ret = 0;
+ goto out;
+ }
iter->level = depth_want;
- iter->l[iter->level].b = BTREE_ITER_NOT_END;
- return ret;
+
+ if (ret == -EIO) {
+ iter->flags |= BTREE_ITER_ERROR;
+ iter->l[iter->level].b =
+ BTREE_ITER_NO_NODE_ERROR;
+ } else {
+ iter->l[iter->level].b =
+ BTREE_ITER_NO_NODE_DOWN;
+ }
+ goto out;
}
}
iter->uptodate = BTREE_ITER_NEED_PEEK;
-
- bch2_btree_trans_verify_locks(iter->trans);
- __bch2_btree_iter_verify(iter, iter->l[iter->level].b);
- return 0;
+out:
+ trace_iter_traverse(iter->trans->ip, trace_ip,
+ iter->btree_id, &iter->real_pos, ret);
+ bch2_btree_iter_verify(iter);
+ return ret;
}
-int __must_check bch2_btree_iter_traverse(struct btree_iter *iter)
+static int __must_check __bch2_btree_iter_traverse(struct btree_iter *iter)
{
+ struct btree_trans *trans = iter->trans;
int ret;
- ret = __bch2_btree_iter_traverse(iter);
+ ret = bch2_trans_cond_resched(trans) ?:
+ btree_iter_traverse_one(iter, _RET_IP_);
if (unlikely(ret))
- ret = __btree_iter_traverse_all(iter->trans, iter, ret);
+ ret = __btree_iter_traverse_all(trans, ret, _RET_IP_);
return ret;
}
-static inline void bch2_btree_iter_checks(struct btree_iter *iter,
- enum btree_iter_type type)
+/*
+ * Note:
+ * bch2_btree_iter_traverse() is for external users, btree_iter_traverse() is
+ * for internal btree iterator users
+ *
+ * bch2_btree_iter_traverse sets iter->real_pos to iter->pos,
+ * btree_iter_traverse() does not:
+ */
+static inline int __must_check
+btree_iter_traverse(struct btree_iter *iter)
{
- EBUG_ON(iter->btree_id >= BTREE_ID_NR);
- EBUG_ON(!!(iter->flags & BTREE_ITER_IS_EXTENTS) !=
- (iter->btree_id == BTREE_ID_EXTENTS &&
- type != BTREE_ITER_NODES));
+ return iter->uptodate >= BTREE_ITER_NEED_RELOCK
+ ? __bch2_btree_iter_traverse(iter)
+ : 0;
+}
- bch2_btree_trans_verify_locks(iter->trans);
+int __must_check
+bch2_btree_iter_traverse(struct btree_iter *iter)
+{
+ int ret;
+
+ btree_iter_set_search_pos(iter, btree_iter_search_key(iter));
+
+ ret = btree_iter_traverse(iter);
+ if (ret)
+ return ret;
+
+ iter->should_be_locked = true;
+ return 0;
}
/* Iterate across nodes (leaf and interior nodes) */
struct btree *b;
int ret;
- bch2_btree_iter_checks(iter, BTREE_ITER_NODES);
-
- if (iter->uptodate == BTREE_ITER_UPTODATE)
- return iter->l[iter->level].b;
+ EBUG_ON(btree_iter_type(iter) != BTREE_ITER_NODES);
+ bch2_btree_iter_verify(iter);
- ret = bch2_btree_iter_traverse(iter);
+ ret = btree_iter_traverse(iter);
if (ret)
return NULL;
if (!b)
return NULL;
- BUG_ON(bkey_cmp(b->key.k.p, iter->pos) < 0);
+ BUG_ON(bpos_cmp(b->key.k.p, iter->pos) < 0);
- iter->pos = b->key.k.p;
- iter->uptodate = BTREE_ITER_UPTODATE;
+ iter->pos = iter->real_pos = b->key.k.p;
+
+ bch2_btree_iter_verify(iter);
+ iter->should_be_locked = true;
return b;
}
-struct btree *bch2_btree_iter_next_node(struct btree_iter *iter, unsigned depth)
+struct btree *bch2_btree_iter_next_node(struct btree_iter *iter)
{
struct btree *b;
int ret;
- bch2_btree_iter_checks(iter, BTREE_ITER_NODES);
+ EBUG_ON(btree_iter_type(iter) != BTREE_ITER_NODES);
+ bch2_btree_iter_verify(iter);
/* already got to end? */
if (!btree_iter_node(iter, iter->level))
bch2_trans_cond_resched(iter->trans);
- btree_iter_up(iter);
-
- if (!bch2_btree_node_relock(iter, iter->level))
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_RELOCK);
+ btree_node_unlock(iter, iter->level);
+ iter->l[iter->level].b = BTREE_ITER_NO_NODE_UP;
+ iter->level++;
- ret = bch2_btree_iter_traverse(iter);
+ btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
+ ret = btree_iter_traverse(iter);
if (ret)
return NULL;
if (!b)
return NULL;
- if (bkey_cmp(iter->pos, b->key.k.p) < 0) {
+ if (bpos_cmp(iter->pos, b->key.k.p) < 0) {
/*
* Haven't gotten to the end of the parent node: go back down to
* the next child node
*/
+ btree_iter_set_search_pos(iter, bpos_successor(iter->pos));
- /*
- * We don't really want to be unlocking here except we can't
- * directly tell btree_iter_traverse() "traverse to this level"
- * except by setting iter->level, so we have to unlock so we
- * don't screw up our lock invariants:
- */
- if (btree_node_read_locked(iter, iter->level))
- btree_node_unlock(iter, iter->level);
-
- /* ick: */
- iter->pos = iter->btree_id == BTREE_ID_INODES
- ? btree_type_successor(iter->btree_id, iter->pos)
- : bkey_successor(iter->pos);
- iter->level = depth;
+ /* Unlock to avoid screwing up our lock invariants: */
+ btree_node_unlock(iter, iter->level);
+ iter->level = iter->min_depth;
btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
- ret = bch2_btree_iter_traverse(iter);
+ bch2_btree_iter_verify(iter);
+
+ ret = btree_iter_traverse(iter);
if (ret)
return NULL;
b = iter->l[iter->level].b;
}
- iter->pos = b->key.k.p;
- iter->uptodate = BTREE_ITER_UPTODATE;
+ iter->pos = iter->real_pos = b->key.k.p;
+
+ bch2_btree_iter_verify(iter);
+ iter->should_be_locked = true;
return b;
}
/* Iterate across keys (in leaf nodes only) */
-void bch2_btree_iter_set_pos_same_leaf(struct btree_iter *iter, struct bpos new_pos)
+static void btree_iter_set_search_pos(struct btree_iter *iter, struct bpos new_pos)
{
- struct btree_iter_level *l = &iter->l[0];
-
- EBUG_ON(iter->level != 0);
- EBUG_ON(bkey_cmp(new_pos, iter->pos) < 0);
- EBUG_ON(!btree_node_locked(iter, 0));
- EBUG_ON(bkey_cmp(new_pos, l->b->key.k.p) > 0);
+#ifdef CONFIG_BCACHEFS_DEBUG
+ struct bpos old_pos = iter->real_pos;
+#endif
+ int cmp = bpos_cmp(new_pos, iter->real_pos);
+ unsigned l = iter->level;
- iter->pos = new_pos;
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
+ if (!cmp)
+ goto out;
- btree_iter_advance_to_pos(iter, l, -1);
+ iter->real_pos = new_pos;
+ iter->should_be_locked = false;
- if (bch2_btree_node_iter_end(&l->iter) &&
- btree_iter_pos_after_node(iter, l->b))
+ if (unlikely(btree_iter_type(iter) == BTREE_ITER_CACHED)) {
+ btree_node_unlock(iter, 0);
+ iter->l[0].b = BTREE_ITER_NO_NODE_CACHED;
btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
-}
-
-void bch2_btree_iter_set_pos(struct btree_iter *iter, struct bpos new_pos)
-{
- int cmp = bkey_cmp(new_pos, iter->pos);
- unsigned level;
-
- if (!cmp)
return;
+ }
- iter->pos = new_pos;
-
- level = btree_iter_up_until_locked(iter, true);
+ l = btree_iter_up_until_good_node(iter, cmp);
- if (btree_iter_node(iter, level)) {
+ if (btree_iter_node(iter, l)) {
/*
* We might have to skip over many keys, or just a few: try
* advancing the node iterator, and if we have to skip over too
* is expensive).
*/
if (cmp < 0 ||
- !btree_iter_advance_to_pos(iter, &iter->l[level], 8))
- __btree_iter_init(iter, level);
+ !btree_iter_advance_to_pos(iter, &iter->l[l], 8))
+ __btree_iter_init(iter, l);
/* Don't leave it locked if we're not supposed to: */
- if (btree_lock_want(iter, level) == BTREE_NODE_UNLOCKED)
- btree_node_unlock(iter, level);
+ if (btree_lock_want(iter, l) == BTREE_NODE_UNLOCKED)
+ btree_node_unlock(iter, l);
}
-
- if (level != iter->level)
+out:
+ if (l != iter->level)
btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
else
btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
+
+ bch2_btree_iter_verify(iter);
+#ifdef CONFIG_BCACHEFS_DEBUG
+ trace_iter_set_search_pos(iter->trans->ip, _RET_IP_,
+ iter->btree_id,
+ &old_pos, &new_pos, l);
+#endif
}
-static inline struct bkey_s_c btree_iter_peek_uptodate(struct btree_iter *iter)
+inline bool bch2_btree_iter_advance(struct btree_iter *iter)
{
- struct btree_iter_level *l = &iter->l[0];
- struct bkey_s_c ret = { .k = &iter->k };
-
- if (!bkey_deleted(&iter->k)) {
- EBUG_ON(bch2_btree_node_iter_end(&l->iter));
- ret.v = bkeyp_val(&l->b->format,
- __bch2_btree_node_iter_peek_all(&l->iter, l->b));
- }
+ struct bpos pos = iter->k.p;
+ bool ret = bpos_cmp(pos, POS_MAX) != 0;
- if (debug_check_bkeys(iter->trans->c) &&
- !bkey_deleted(ret.k))
- bch2_bkey_debugcheck(iter->trans->c, l->b, ret);
+ if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
+ pos = bkey_successor(iter, pos);
+ bch2_btree_iter_set_pos(iter, pos);
return ret;
}
-struct bkey_s_c bch2_btree_iter_peek(struct btree_iter *iter)
+inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
{
- struct btree_iter_level *l = &iter->l[0];
- struct bkey_s_c k;
- int ret;
-
- bch2_btree_iter_checks(iter, BTREE_ITER_KEYS);
-
- if (iter->uptodate == BTREE_ITER_UPTODATE)
- return btree_iter_peek_uptodate(iter);
-
- while (1) {
- ret = bch2_btree_iter_traverse(iter);
- if (unlikely(ret))
- return bkey_s_c_err(ret);
+ struct bpos pos = bkey_start_pos(&iter->k);
+ bool ret = bpos_cmp(pos, POS_MIN) != 0;
- k = __btree_iter_peek(iter, l);
- if (likely(k.k))
- break;
-
- /* got to the end of the leaf, iterator needs to be traversed: */
- iter->pos = l->b->key.k.p;
- iter->uptodate = BTREE_ITER_NEED_TRAVERSE;
-
- if (!bkey_cmp(iter->pos, POS_MAX))
- return bkey_s_c_null;
+ if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
+ pos = bkey_predecessor(iter, pos);
+ bch2_btree_iter_set_pos(iter, pos);
+ return ret;
+}
- iter->pos = btree_type_successor(iter->btree_id, iter->pos);
- }
+static inline bool btree_iter_set_pos_to_next_leaf(struct btree_iter *iter)
+{
+ struct bpos next_pos = iter->l[0].b->key.k.p;
+ bool ret = bpos_cmp(next_pos, POS_MAX) != 0;
/*
- * iter->pos should always be equal to the key we just
- * returned - except extents can straddle iter->pos:
+ * Typically, we don't want to modify iter->pos here, since that
+ * indicates where we searched from - unless we got to the end of the
+ * btree, in that case we want iter->pos to reflect that:
*/
- if (!(iter->flags & BTREE_ITER_IS_EXTENTS) ||
- bkey_cmp(bkey_start_pos(k.k), iter->pos) > 0)
- iter->pos = bkey_start_pos(k.k);
+ if (ret)
+ btree_iter_set_search_pos(iter, bpos_successor(next_pos));
+ else
+ bch2_btree_iter_set_pos(iter, POS_MAX);
- iter->uptodate = BTREE_ITER_UPTODATE;
- return k;
+ return ret;
}
-static noinline
-struct bkey_s_c bch2_btree_iter_peek_next_leaf(struct btree_iter *iter)
+static inline bool btree_iter_set_pos_to_prev_leaf(struct btree_iter *iter)
{
- struct btree_iter_level *l = &iter->l[0];
-
- iter->pos = l->b->key.k.p;
- iter->uptodate = BTREE_ITER_NEED_TRAVERSE;
+ struct bpos next_pos = iter->l[0].b->data->min_key;
+ bool ret = bpos_cmp(next_pos, POS_MIN) != 0;
- if (!bkey_cmp(iter->pos, POS_MAX))
- return bkey_s_c_null;
-
- iter->pos = btree_type_successor(iter->btree_id, iter->pos);
+ if (ret)
+ btree_iter_set_search_pos(iter, bpos_predecessor(next_pos));
+ else
+ bch2_btree_iter_set_pos(iter, POS_MIN);
- return bch2_btree_iter_peek(iter);
+ return ret;
}
-struct bkey_s_c bch2_btree_iter_next(struct btree_iter *iter)
+static inline struct bkey_i *btree_trans_peek_updates(struct btree_iter *iter,
+ struct bpos pos)
{
- struct btree_iter_level *l = &iter->l[0];
- struct bkey_packed *p;
- struct bkey_s_c k;
-
- bch2_btree_iter_checks(iter, BTREE_ITER_KEYS);
-
- if (unlikely(iter->uptodate != BTREE_ITER_UPTODATE)) {
- k = bch2_btree_iter_peek(iter);
- if (IS_ERR_OR_NULL(k.k))
- return k;
- }
+ struct btree_insert_entry *i;
- do {
- bch2_btree_node_iter_advance(&l->iter, l->b);
- p = bch2_btree_node_iter_peek_all(&l->iter, l->b);
- if (unlikely(!p))
- return bch2_btree_iter_peek_next_leaf(iter);
- } while (bkey_whiteout(p));
+ if (!(iter->flags & BTREE_ITER_WITH_UPDATES))
+ return NULL;
- k = __btree_iter_unpack(iter, l, &iter->k, p);
+ trans_for_each_update(iter->trans, i)
+ if ((cmp_int(iter->btree_id, i->iter->btree_id) ?:
+ bkey_cmp(pos, i->k->k.p)) <= 0) {
+ if (iter->btree_id == i->iter->btree_id)
+ return i->k;
+ break;
+ }
- EBUG_ON(bkey_cmp(bkey_start_pos(k.k), iter->pos) < 0);
- iter->pos = bkey_start_pos(k.k);
- return k;
+ return NULL;
}
-struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *iter)
+/**
+ * bch2_btree_iter_peek: returns first key greater than or equal to iterator's
+ * current position
+ */
+struct bkey_s_c bch2_btree_iter_peek(struct btree_iter *iter)
{
- struct btree_iter_level *l = &iter->l[0];
- struct bkey_packed *p;
+ struct bpos search_key = btree_iter_search_key(iter);
+ struct bkey_i *next_update;
struct bkey_s_c k;
int ret;
- bch2_btree_iter_checks(iter, BTREE_ITER_KEYS);
-
- if (unlikely(iter->uptodate != BTREE_ITER_UPTODATE)) {
- k = bch2_btree_iter_peek(iter);
- if (IS_ERR(k.k))
- return k;
- }
+ EBUG_ON(btree_iter_type(iter) != BTREE_ITER_KEYS);
+ bch2_btree_iter_verify(iter);
+ bch2_btree_iter_verify_entry_exit(iter);
+start:
+ next_update = btree_trans_peek_updates(iter, search_key);
+ btree_iter_set_search_pos(iter, search_key);
while (1) {
- p = bch2_btree_node_iter_prev(&l->iter, l->b);
- if (likely(p))
- break;
+ ret = btree_iter_traverse(iter);
+ if (unlikely(ret))
+ return bkey_s_c_err(ret);
- iter->pos = l->b->data->min_key;
- if (!bkey_cmp(iter->pos, POS_MIN))
- return bkey_s_c_null;
+ k = btree_iter_level_peek(iter, &iter->l[0]);
- bch2_btree_iter_set_pos(iter,
- btree_type_predecessor(iter->btree_id, iter->pos));
+ if (next_update &&
+ bpos_cmp(next_update->k.p, iter->real_pos) <= 0) {
+ iter->k = next_update->k;
+ k = bkey_i_to_s_c(next_update);
+ }
- ret = bch2_btree_iter_traverse(iter);
- if (unlikely(ret))
- return bkey_s_c_err(ret);
+ if (likely(k.k)) {
+ if (bkey_deleted(k.k)) {
+ search_key = bkey_successor(iter, k.k->p);
+ goto start;
+ }
- p = bch2_btree_node_iter_peek(&l->iter, l->b);
- if (p)
break;
- }
+ }
- k = __btree_iter_unpack(iter, l, &iter->k, p);
+ if (!btree_iter_set_pos_to_next_leaf(iter))
+ return bkey_s_c_null;
+ }
- EBUG_ON(bkey_cmp(bkey_start_pos(k.k), iter->pos) > 0);
+ /*
+ * iter->pos should be mononotically increasing, and always be equal to
+ * the key we just returned - except extents can straddle iter->pos:
+ */
+ if (!(iter->flags & BTREE_ITER_IS_EXTENTS))
+ iter->pos = k.k->p;
+ else if (bkey_cmp(bkey_start_pos(k.k), iter->pos) > 0)
+ iter->pos = bkey_start_pos(k.k);
- iter->pos = bkey_start_pos(k.k);
- iter->uptodate = BTREE_ITER_UPTODATE;
+ bch2_btree_iter_verify_entry_exit(iter);
+ bch2_btree_iter_verify(iter);
+ iter->should_be_locked = true;
return k;
}
-static inline struct bkey_s_c
-__bch2_btree_iter_peek_slot_extents(struct btree_iter *iter)
+/**
+ * bch2_btree_iter_next: returns first key greater than iterator's current
+ * position
+ */
+struct bkey_s_c bch2_btree_iter_next(struct btree_iter *iter)
+{
+ if (!bch2_btree_iter_advance(iter))
+ return bkey_s_c_null;
+
+ return bch2_btree_iter_peek(iter);
+}
+
+/**
+ * bch2_btree_iter_peek_prev: returns first key less than or equal to
+ * iterator's current position
+ */
+struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter)
{
struct btree_iter_level *l = &iter->l[0];
- struct btree_node_iter node_iter;
struct bkey_s_c k;
- struct bkey n;
int ret;
-recheck:
- while ((k = __btree_iter_peek_all(iter, l, &iter->k)).k &&
- bkey_deleted(k.k) &&
- bkey_cmp(bkey_start_pos(k.k), iter->pos) == 0)
- bch2_btree_node_iter_advance(&l->iter, l->b);
+ EBUG_ON(btree_iter_type(iter) != BTREE_ITER_KEYS);
+ EBUG_ON(iter->flags & BTREE_ITER_WITH_UPDATES);
+ bch2_btree_iter_verify(iter);
+ bch2_btree_iter_verify_entry_exit(iter);
- /*
- * iterator is now at the correct position for inserting at iter->pos,
- * but we need to keep iterating until we find the first non whiteout so
- * we know how big a hole we have, if any:
- */
+ btree_iter_set_search_pos(iter, iter->pos);
+
+ while (1) {
+ ret = btree_iter_traverse(iter);
+ if (unlikely(ret)) {
+ k = bkey_s_c_err(ret);
+ goto no_key;
+ }
+
+ k = btree_iter_level_peek(iter, l);
+ if (!k.k ||
+ ((iter->flags & BTREE_ITER_IS_EXTENTS)
+ ? bkey_cmp(bkey_start_pos(k.k), iter->pos) >= 0
+ : bkey_cmp(k.k->p, iter->pos) > 0))
+ k = btree_iter_level_prev(iter, l);
+
+ if (likely(k.k))
+ break;
- node_iter = l->iter;
- if (k.k && bkey_whiteout(k.k))
- k = __btree_iter_unpack(iter, l, &iter->k,
- bch2_btree_node_iter_peek(&node_iter, l->b));
+ if (!btree_iter_set_pos_to_prev_leaf(iter)) {
+ k = bkey_s_c_null;
+ goto no_key;
+ }
+ }
+
+ EBUG_ON(bkey_cmp(bkey_start_pos(k.k), iter->pos) > 0);
+ /* Extents can straddle iter->pos: */
+ if (bkey_cmp(k.k->p, iter->pos) < 0)
+ iter->pos = k.k->p;
+out:
+ bch2_btree_iter_verify_entry_exit(iter);
+ bch2_btree_iter_verify(iter);
+ iter->should_be_locked = true;
+ return k;
+no_key:
/*
- * If we got to the end of the node, check if we need to traverse to the
- * next node:
+ * btree_iter_level_peek() may have set iter->k to a key we didn't want, and
+ * then we errored going to the previous leaf - make sure it's
+ * consistent with iter->pos:
*/
- if (unlikely(!k.k && btree_iter_pos_after_node(iter, l->b))) {
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
- ret = bch2_btree_iter_traverse(iter);
- if (unlikely(ret))
- return bkey_s_c_err(ret);
+ bkey_init(&iter->k);
+ iter->k.p = iter->pos;
+ goto out;
+}
- goto recheck;
- }
+/**
+ * bch2_btree_iter_prev: returns first key less than iterator's current
+ * position
+ */
+struct bkey_s_c bch2_btree_iter_prev(struct btree_iter *iter)
+{
+ if (!bch2_btree_iter_rewind(iter))
+ return bkey_s_c_null;
- if (k.k &&
- !bkey_whiteout(k.k) &&
- bkey_cmp(bkey_start_pos(k.k), iter->pos) <= 0) {
- /*
- * if we skipped forward to find the first non whiteout and
- * there _wasn't_ actually a hole, we want the iterator to be
- * pointed at the key we found:
- */
- l->iter = node_iter;
+ return bch2_btree_iter_peek_prev(iter);
+}
- EBUG_ON(bkey_cmp(k.k->p, iter->pos) < 0);
- EBUG_ON(bkey_deleted(k.k));
- iter->uptodate = BTREE_ITER_UPTODATE;
- return k;
- }
+struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter)
+{
+ struct bpos search_key;
+ struct bkey_s_c k;
+ int ret;
- /* hole */
+ EBUG_ON(btree_iter_type(iter) != BTREE_ITER_KEYS &&
+ btree_iter_type(iter) != BTREE_ITER_CACHED);
+ bch2_btree_iter_verify(iter);
+ bch2_btree_iter_verify_entry_exit(iter);
- /* holes can't span inode numbers: */
- if (iter->pos.offset == KEY_OFFSET_MAX) {
+ /* extents can't span inode numbers: */
+ if ((iter->flags & BTREE_ITER_IS_EXTENTS) &&
+ unlikely(iter->pos.offset == KEY_OFFSET_MAX)) {
if (iter->pos.inode == KEY_INODE_MAX)
return bkey_s_c_null;
- iter->pos = bkey_successor(iter->pos);
- goto recheck;
+ bch2_btree_iter_set_pos(iter, bpos_nosnap_successor(iter->pos));
}
- if (!k.k)
- k.k = &l->b->key.k;
+ search_key = btree_iter_search_key(iter);
+ btree_iter_set_search_pos(iter, search_key);
- bkey_init(&n);
- n.p = iter->pos;
- bch2_key_resize(&n,
- min_t(u64, KEY_SIZE_MAX,
- (k.k->p.inode == n.p.inode
- ? bkey_start_offset(k.k)
- : KEY_OFFSET_MAX) -
- n.p.offset));
+ ret = btree_iter_traverse(iter);
+ if (unlikely(ret))
+ return bkey_s_c_err(ret);
- EBUG_ON(!n.size);
+ if (btree_iter_type(iter) == BTREE_ITER_CACHED ||
+ !(iter->flags & BTREE_ITER_IS_EXTENTS)) {
+ struct bkey_i *next_update;
+ struct bkey_cached *ck;
- iter->k = n;
- iter->uptodate = BTREE_ITER_UPTODATE;
- return (struct bkey_s_c) { &iter->k, NULL };
-}
+ switch (btree_iter_type(iter)) {
+ case BTREE_ITER_KEYS:
+ k = btree_iter_level_peek_all(iter, &iter->l[0]);
+ EBUG_ON(k.k && bkey_deleted(k.k) && bkey_cmp(k.k->p, iter->pos) == 0);
+ break;
+ case BTREE_ITER_CACHED:
+ ck = (void *) iter->l[0].b;
+ EBUG_ON(iter->btree_id != ck->key.btree_id ||
+ bkey_cmp(iter->pos, ck->key.pos));
+ BUG_ON(!ck->valid);
-static inline struct bkey_s_c
-__bch2_btree_iter_peek_slot(struct btree_iter *iter)
-{
- struct btree_iter_level *l = &iter->l[0];
- struct bkey_s_c k;
- int ret;
+ k = bkey_i_to_s_c(ck->k);
+ break;
+ case BTREE_ITER_NODES:
+ BUG();
+ }
- if (iter->flags & BTREE_ITER_IS_EXTENTS)
- return __bch2_btree_iter_peek_slot_extents(iter);
+ next_update = btree_trans_peek_updates(iter, search_key);
+ if (next_update &&
+ (!k.k || bpos_cmp(next_update->k.p, k.k->p) <= 0)) {
+ iter->k = next_update->k;
+ k = bkey_i_to_s_c(next_update);
+ }
+ } else {
+ if ((iter->flags & BTREE_ITER_INTENT)) {
+ struct btree_iter *child =
+ btree_iter_child_alloc(iter, _THIS_IP_);
-recheck:
- while ((k = __btree_iter_peek_all(iter, l, &iter->k)).k &&
- bkey_deleted(k.k) &&
- bkey_cmp(k.k->p, iter->pos) == 0)
- bch2_btree_node_iter_advance(&l->iter, l->b);
+ btree_iter_copy(child, iter);
+ k = bch2_btree_iter_peek(child);
- /*
- * If we got to the end of the node, check if we need to traverse to the
- * next node:
- */
- if (unlikely(!k.k && btree_iter_pos_after_node(iter, l->b))) {
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
- ret = bch2_btree_iter_traverse(iter);
- if (unlikely(ret))
- return bkey_s_c_err(ret);
+ if (k.k && !bkey_err(k))
+ iter->k = child->k;
+ } else {
+ struct bpos pos = iter->pos;
+
+ k = bch2_btree_iter_peek(iter);
+ iter->pos = pos;
+ }
- goto recheck;
+ if (unlikely(bkey_err(k)))
+ return k;
}
- if (k.k &&
- !bkey_deleted(k.k) &&
- !bkey_cmp(iter->pos, k.k->p)) {
- iter->uptodate = BTREE_ITER_UPTODATE;
- return k;
+ if (!(iter->flags & BTREE_ITER_IS_EXTENTS)) {
+ if (!k.k ||
+ ((iter->flags & BTREE_ITER_ALL_SNAPSHOTS)
+ ? bpos_cmp(iter->pos, k.k->p)
+ : bkey_cmp(iter->pos, k.k->p))) {
+ bkey_init(&iter->k);
+ iter->k.p = iter->pos;
+ k = (struct bkey_s_c) { &iter->k, NULL };
+ }
} else {
- /* hole */
- bkey_init(&iter->k);
- iter->k.p = iter->pos;
-
- iter->uptodate = BTREE_ITER_UPTODATE;
- return (struct bkey_s_c) { &iter->k, NULL };
+ struct bpos next = k.k ? bkey_start_pos(k.k) : POS_MAX;
+
+ if (bkey_cmp(iter->pos, next) < 0) {
+ bkey_init(&iter->k);
+ iter->k.p = iter->pos;
+ bch2_key_resize(&iter->k,
+ min_t(u64, KEY_SIZE_MAX,
+ (next.inode == iter->pos.inode
+ ? next.offset
+ : KEY_OFFSET_MAX) -
+ iter->pos.offset));
+
+ k = (struct bkey_s_c) { &iter->k, NULL };
+ EBUG_ON(!k.k->size);
+ }
}
-}
-
-struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter)
-{
- int ret;
-
- bch2_btree_iter_checks(iter, BTREE_ITER_SLOTS);
-
- if (iter->uptodate == BTREE_ITER_UPTODATE)
- return btree_iter_peek_uptodate(iter);
- ret = bch2_btree_iter_traverse(iter);
- if (unlikely(ret))
- return bkey_s_c_err(ret);
+ bch2_btree_iter_verify_entry_exit(iter);
+ bch2_btree_iter_verify(iter);
+ iter->should_be_locked = true;
- return __bch2_btree_iter_peek_slot(iter);
+ return k;
}
struct bkey_s_c bch2_btree_iter_next_slot(struct btree_iter *iter)
{
- bch2_btree_iter_checks(iter, BTREE_ITER_SLOTS);
-
- iter->pos = btree_type_successor(iter->btree_id, iter->k.p);
-
- if (unlikely(iter->uptodate != BTREE_ITER_UPTODATE)) {
- /*
- * XXX: when we just need to relock we should be able to avoid
- * calling traverse, but we need to kill BTREE_ITER_NEED_PEEK
- * for that to work
- */
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_TRAVERSE);
-
- return bch2_btree_iter_peek_slot(iter);
- }
+ if (!bch2_btree_iter_advance(iter))
+ return bkey_s_c_null;
- if (!bkey_deleted(&iter->k))
- bch2_btree_node_iter_advance(&iter->l[0].iter, iter->l[0].b);
+ return bch2_btree_iter_peek_slot(iter);
+}
- btree_iter_set_dirty(iter, BTREE_ITER_NEED_PEEK);
+struct bkey_s_c bch2_btree_iter_prev_slot(struct btree_iter *iter)
+{
+ if (!bch2_btree_iter_rewind(iter))
+ return bkey_s_c_null;
- return __bch2_btree_iter_peek_slot(iter);
+ return bch2_btree_iter_peek_slot(iter);
}
static inline void bch2_btree_iter_init(struct btree_trans *trans,
- struct btree_iter *iter, enum btree_id btree_id,
- struct bpos pos, unsigned flags)
+ struct btree_iter *iter, enum btree_id btree_id)
{
struct bch_fs *c = trans->c;
unsigned i;
- if (btree_id == BTREE_ID_EXTENTS &&
- !(flags & BTREE_ITER_NODES))
- flags |= BTREE_ITER_IS_EXTENTS;
-
iter->trans = trans;
- iter->pos = pos;
- bkey_init(&iter->k);
- iter->k.p = pos;
- iter->flags = flags;
iter->uptodate = BTREE_ITER_NEED_TRAVERSE;
iter->btree_id = btree_id;
+ iter->real_pos = POS_MIN;
iter->level = 0;
- iter->locks_want = flags & BTREE_ITER_INTENT ? 1 : 0;
+ iter->min_depth = 0;
+ iter->locks_want = 0;
iter->nodes_locked = 0;
iter->nodes_intent_locked = 0;
for (i = 0; i < ARRAY_SIZE(iter->l); i++)
- iter->l[i].b = NULL;
- iter->l[iter->level].b = BTREE_ITER_NOT_END;
+ iter->l[i].b = BTREE_ITER_NO_NODE_INIT;
prefetch(c->btree_roots[btree_id].b);
}
/* new transactional stuff: */
-int bch2_trans_iter_put(struct btree_trans *trans,
- struct btree_iter *iter)
+static void btree_iter_child_free(struct btree_iter *iter)
{
- int ret = btree_iter_err(iter);
+ struct btree_iter *child = btree_iter_child(iter);
- trans->iters_live &= ~(1ULL << iter->idx);
- return ret;
+ if (child) {
+ bch2_trans_iter_free(iter->trans, child);
+ iter->child_idx = U8_MAX;
+ }
+}
+
+static struct btree_iter *btree_iter_child_alloc(struct btree_iter *iter,
+ unsigned long ip)
+{
+ struct btree_trans *trans = iter->trans;
+ struct btree_iter *child = btree_iter_child(iter);
+
+ if (!child) {
+ child = btree_trans_iter_alloc(trans);
+ child->ip_allocated = ip;
+ iter->child_idx = child->idx;
+
+ trans->iters_live |= 1ULL << child->idx;
+ trans->iters_touched |= 1ULL << child->idx;
+ }
+
+ return child;
}
static inline void __bch2_trans_iter_free(struct btree_trans *trans,
unsigned idx)
{
+ btree_iter_child_free(&trans->iters[idx]);
+
__bch2_btree_iter_unlock(&trans->iters[idx]);
trans->iters_linked &= ~(1ULL << idx);
trans->iters_live &= ~(1ULL << idx);
trans->iters_touched &= ~(1ULL << idx);
- trans->iters_unlink_on_restart &= ~(1ULL << idx);
- trans->iters_unlink_on_commit &= ~(1ULL << idx);
+}
+
+int bch2_trans_iter_put(struct btree_trans *trans,
+ struct btree_iter *iter)
+{
+ int ret;
+
+ if (IS_ERR_OR_NULL(iter))
+ return 0;
+
+ BUG_ON(trans->iters + iter->idx != iter);
+ BUG_ON(!btree_iter_live(trans, iter));
+
+ ret = btree_iter_err(iter);
+
+ if (!(trans->iters_touched & (1ULL << iter->idx)) &&
+ !(iter->flags & BTREE_ITER_KEEP_UNTIL_COMMIT))
+ __bch2_trans_iter_free(trans, iter->idx);
+
+ trans->iters_live &= ~(1ULL << iter->idx);
+ return ret;
}
int bch2_trans_iter_free(struct btree_trans *trans,
struct btree_iter *iter)
{
- int ret = btree_iter_err(iter);
+ if (IS_ERR_OR_NULL(iter))
+ return 0;
- __bch2_trans_iter_free(trans, iter->idx);
- return ret;
+ set_btree_iter_dontneed(trans, iter);
+
+ return bch2_trans_iter_put(trans, iter);
}
-int bch2_trans_iter_free_on_commit(struct btree_trans *trans,
- struct btree_iter *iter)
+noinline __cold
+static void btree_trans_iter_alloc_fail(struct btree_trans *trans)
{
- int ret = btree_iter_err(iter);
- trans->iters_unlink_on_commit |= 1ULL << iter->idx;
- return ret;
+ struct btree_iter *iter;
+ struct btree_insert_entry *i;
+ char buf[100];
+
+ trans_for_each_iter(trans, iter)
+ printk(KERN_ERR "iter: btree %s pos %s%s%s%s %pS\n",
+ bch2_btree_ids[iter->btree_id],
+ (bch2_bpos_to_text(&PBUF(buf), iter->pos), buf),
+ btree_iter_live(trans, iter) ? " live" : "",
+ (trans->iters_touched & (1ULL << iter->idx)) ? " touched" : "",
+ iter->flags & BTREE_ITER_KEEP_UNTIL_COMMIT ? " keep" : "",
+ (void *) iter->ip_allocated);
+
+ trans_for_each_update(trans, i) {
+ char buf[300];
+
+ bch2_bkey_val_to_text(&PBUF(buf), trans->c, bkey_i_to_s_c(i->k));
+ printk(KERN_ERR "update: btree %s %s\n",
+ bch2_btree_ids[i->iter->btree_id], buf);
+ }
+ panic("trans iter oveflow\n");
}
-static int btree_trans_realloc_iters(struct btree_trans *trans,
- unsigned new_size)
+static struct btree_iter *btree_trans_iter_alloc(struct btree_trans *trans)
{
- void *new_iters, *new_updates;
+ struct btree_iter *iter;
+ unsigned idx;
- BUG_ON(new_size > BTREE_ITER_MAX);
+ if (unlikely(trans->iters_linked ==
+ ~((~0ULL << 1) << (BTREE_ITER_MAX - 1))))
+ btree_trans_iter_alloc_fail(trans);
- if (new_size <= trans->size)
- return 0;
+ idx = __ffs64(~trans->iters_linked);
+ iter = &trans->iters[idx];
- BUG_ON(trans->used_mempool);
+ iter->trans = trans;
+ iter->idx = idx;
+ iter->child_idx = U8_MAX;
+ iter->flags = 0;
+ iter->nodes_locked = 0;
+ iter->nodes_intent_locked = 0;
+ trans->iters_linked |= 1ULL << idx;
+ return iter;
+}
- bch2_trans_unlock(trans);
+static void btree_iter_copy(struct btree_iter *dst, struct btree_iter *src)
+{
+ unsigned i;
- new_iters = kmalloc(sizeof(struct btree_iter) * new_size +
- sizeof(struct btree_insert_entry) * (new_size + 4),
- GFP_NOFS);
- if (new_iters)
- goto success;
+ __bch2_btree_iter_unlock(dst);
+ btree_iter_child_free(dst);
- new_iters = mempool_alloc(&trans->c->btree_iters_pool, GFP_NOFS);
- new_size = BTREE_ITER_MAX;
+ memcpy(&dst->flags, &src->flags,
+ sizeof(struct btree_iter) - offsetof(struct btree_iter, flags));
- trans->used_mempool = true;
-success:
- new_updates = new_iters + sizeof(struct btree_iter) * new_size;
+ for (i = 0; i < BTREE_MAX_DEPTH; i++)
+ if (btree_node_locked(dst, i))
+ six_lock_increment(&dst->l[i].b->c.lock,
+ __btree_lock_want(dst, i));
- memcpy(new_iters, trans->iters,
- sizeof(struct btree_iter) * trans->nr_iters);
- memcpy(new_updates, trans->updates,
- sizeof(struct btree_insert_entry) * trans->nr_updates);
+ dst->flags &= ~BTREE_ITER_KEEP_UNTIL_COMMIT;
+ dst->flags &= ~BTREE_ITER_SET_POS_AFTER_COMMIT;
+}
- if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG))
- memset(trans->iters, POISON_FREE,
- sizeof(struct btree_iter) * trans->nr_iters +
- sizeof(struct btree_insert_entry) * trans->nr_iters);
+struct btree_iter *__bch2_trans_get_iter(struct btree_trans *trans,
+ unsigned btree_id, struct bpos pos,
+ unsigned locks_want,
+ unsigned depth,
+ unsigned flags)
+{
+ struct btree_iter *iter, *best = NULL;
+ struct bpos real_pos, pos_min = POS_MIN;
+
+ if ((flags & BTREE_ITER_TYPE) != BTREE_ITER_NODES &&
+ btree_node_type_is_extents(btree_id) &&
+ !(flags & BTREE_ITER_NOT_EXTENTS) &&
+ !(flags & BTREE_ITER_ALL_SNAPSHOTS))
+ flags |= BTREE_ITER_IS_EXTENTS;
- if (trans->iters != trans->iters_onstack)
- kfree(trans->iters);
+ if ((flags & BTREE_ITER_TYPE) != BTREE_ITER_NODES &&
+ !btree_type_has_snapshots(btree_id))
+ flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
- trans->iters = new_iters;
- trans->updates = new_updates;
- trans->size = new_size;
+ if (!(flags & BTREE_ITER_ALL_SNAPSHOTS))
+ pos.snapshot = btree_type_has_snapshots(btree_id)
+ ? U32_MAX : 0;
- if (trans->iters_live) {
- trans_restart();
- return -EINTR;
- }
+ real_pos = pos;
- return 0;
-}
+ if ((flags & BTREE_ITER_IS_EXTENTS) &&
+ bkey_cmp(pos, POS_MAX))
+ real_pos = bpos_nosnap_successor(pos);
-void bch2_trans_preload_iters(struct btree_trans *trans)
-{
- btree_trans_realloc_iters(trans, BTREE_ITER_MAX);
-}
+ trans_for_each_iter(trans, iter) {
+ if (btree_iter_type(iter) != (flags & BTREE_ITER_TYPE))
+ continue;
-static int btree_trans_iter_alloc(struct btree_trans *trans)
-{
- unsigned idx = __ffs64(~trans->iters_linked);
+ if (iter->btree_id != btree_id)
+ continue;
- if (idx < trans->nr_iters)
- goto got_slot;
+ if (best) {
+ int cmp = bkey_cmp(bpos_diff(best->real_pos, real_pos),
+ bpos_diff(iter->real_pos, real_pos));
- if (trans->nr_iters == trans->size) {
- int ret = btree_trans_realloc_iters(trans, trans->size * 2);
- if (ret)
- return ret;
+ if (cmp < 0 ||
+ ((cmp == 0 && btree_iter_keep(trans, iter))))
+ continue;
+ }
+
+ best = iter;
}
- idx = trans->nr_iters++;
- BUG_ON(trans->nr_iters > trans->size);
+ if (!best) {
+ iter = btree_trans_iter_alloc(trans);
+ bch2_btree_iter_init(trans, iter, btree_id);
+ } else if (btree_iter_keep(trans, best)) {
+ iter = btree_trans_iter_alloc(trans);
+ btree_iter_copy(iter, best);
+ } else {
+ iter = best;
+ }
- trans->iters[idx].idx = idx;
-got_slot:
- BUG_ON(trans->iters_linked & (1ULL << idx));
- trans->iters_linked |= 1ULL << idx;
- return idx;
-}
+ trans->iters_live |= 1ULL << iter->idx;
+ trans->iters_touched |= 1ULL << iter->idx;
-static struct btree_iter *__btree_trans_get_iter(struct btree_trans *trans,
- unsigned btree_id, struct bpos pos,
- unsigned flags, u64 iter_id)
-{
- struct btree_iter *iter;
- int idx;
+ iter->flags = flags;
- BUG_ON(trans->nr_iters > BTREE_ITER_MAX);
+ iter->snapshot = pos.snapshot;
- for (idx = 0; idx < trans->nr_iters; idx++) {
- if (!(trans->iters_linked & (1ULL << idx)))
- continue;
+ /*
+ * If the iterator has locks_want greater than requested, we explicitly
+ * do not downgrade it here - on transaction restart because btree node
+ * split needs to upgrade locks, we might be putting/getting the
+ * iterator again. Downgrading iterators only happens via an explicit
+ * bch2_trans_downgrade().
+ */
- iter = &trans->iters[idx];
- if (iter_id
- ? iter->id == iter_id
- : (iter->btree_id == btree_id &&
- !bkey_cmp(iter->pos, pos)))
- goto found;
+ locks_want = min(locks_want, BTREE_MAX_DEPTH);
+ if (locks_want > iter->locks_want) {
+ iter->locks_want = locks_want;
+ btree_iter_get_locks(iter, true, _THIS_IP_);
}
- idx = -1;
-found:
- if (idx < 0) {
- idx = btree_trans_iter_alloc(trans);
- if (idx < 0)
- return ERR_PTR(idx);
-
- iter = &trans->iters[idx];
- iter->id = iter_id;
- bch2_btree_iter_init(trans, iter, btree_id, pos, flags);
- } else {
- iter = &trans->iters[idx];
-
- iter->flags &= ~(BTREE_ITER_INTENT|BTREE_ITER_PREFETCH);
- iter->flags |= flags & (BTREE_ITER_INTENT|BTREE_ITER_PREFETCH);
+ while (iter->level != depth) {
+ btree_node_unlock(iter, iter->level);
+ iter->l[iter->level].b = BTREE_ITER_NO_NODE_INIT;
+ iter->uptodate = BTREE_ITER_NEED_TRAVERSE;
+ if (iter->level < depth)
+ iter->level++;
+ else
+ iter->level--;
}
- BUG_ON(iter->btree_id != btree_id);
- BUG_ON(trans->iters_live & (1ULL << idx));
- trans->iters_live |= 1ULL << idx;
- trans->iters_touched |= 1ULL << idx;
+ iter->min_depth = depth;
- BUG_ON(iter->btree_id != btree_id);
- BUG_ON((iter->flags ^ flags) & BTREE_ITER_TYPE);
+ bch2_btree_iter_set_pos(iter, pos);
+ btree_iter_set_search_pos(iter, real_pos);
- return iter;
-}
+ trace_trans_get_iter(_RET_IP_, trans->ip,
+ btree_id,
+ &real_pos, locks_want, iter->uptodate,
+ best ? &best->real_pos : &pos_min,
+ best ? best->locks_want : U8_MAX,
+ best ? best->uptodate : U8_MAX);
-struct btree_iter *__bch2_trans_get_iter(struct btree_trans *trans,
- enum btree_id btree_id,
- struct bpos pos, unsigned flags,
- u64 iter_id)
-{
- struct btree_iter *iter =
- __btree_trans_get_iter(trans, btree_id, pos, flags, iter_id);
-
- if (!IS_ERR(iter))
- bch2_btree_iter_set_pos(iter, pos);
return iter;
}
unsigned flags)
{
struct btree_iter *iter =
- __btree_trans_get_iter(trans, btree_id, pos,
- flags|BTREE_ITER_NODES, 0);
- unsigned i;
+ __bch2_trans_get_iter(trans, btree_id, pos,
+ locks_want, depth,
+ BTREE_ITER_NODES|
+ BTREE_ITER_NOT_EXTENTS|
+ BTREE_ITER_ALL_SNAPSHOTS|
+ flags);
- BUG_ON(IS_ERR(iter));
BUG_ON(bkey_cmp(iter->pos, pos));
-
- iter->locks_want = locks_want;
- iter->level = depth;
-
- for (i = 0; i < ARRAY_SIZE(iter->l); i++)
- iter->l[i].b = NULL;
- iter->l[iter->level].b = BTREE_ITER_NOT_END;
+ BUG_ON(iter->locks_want != min(locks_want, BTREE_MAX_DEPTH));
+ BUG_ON(iter->level != depth);
+ BUG_ON(iter->min_depth != depth);
+ iter->ip_allocated = _RET_IP_;
return iter;
}
-struct btree_iter *bch2_trans_copy_iter(struct btree_trans *trans,
+struct btree_iter *__bch2_trans_copy_iter(struct btree_trans *trans,
struct btree_iter *src)
{
struct btree_iter *iter;
- int i, idx;
-
- idx = btree_trans_iter_alloc(trans);
- if (idx < 0)
- return ERR_PTR(idx);
- trans->iters_live |= 1ULL << idx;
- trans->iters_touched |= 1ULL << idx;
- trans->iters_unlink_on_restart |= 1ULL << idx;
+ iter = btree_trans_iter_alloc(trans);
+ btree_iter_copy(iter, src);
- iter = &trans->iters[idx];
-
- memcpy(&iter->trans,
- &src->trans,
- (void *) &iter[1] - (void *) &iter->trans);
-
- for (i = 0; i < BTREE_MAX_DEPTH; i++)
- if (btree_node_locked(iter, i))
- six_lock_increment(&iter->l[i].b->lock,
- __btree_lock_want(iter, i));
+ trans->iters_live |= 1ULL << iter->idx;
+ /*
+ * We don't need to preserve this iter since it's cheap to copy it
+ * again - this will cause trans_iter_put() to free it right away:
+ */
+ set_btree_iter_dontneed(trans, iter);
- return &trans->iters[idx];
+ return iter;
}
-void *bch2_trans_kmalloc(struct btree_trans *trans,
- size_t size)
+void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
{
- void *ret;
+ size_t new_top = trans->mem_top + size;
+ void *p;
- if (trans->mem_top + size > trans->mem_bytes) {
+ if (new_top > trans->mem_bytes) {
size_t old_bytes = trans->mem_bytes;
- size_t new_bytes = roundup_pow_of_two(trans->mem_top + size);
- void *new_mem = krealloc(trans->mem, new_bytes, GFP_NOFS);
+ size_t new_bytes = roundup_pow_of_two(new_top);
+ void *new_mem;
+
+ WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX);
+
+ new_mem = krealloc(trans->mem, new_bytes, GFP_NOFS);
+ if (!new_mem && new_bytes <= BTREE_TRANS_MEM_MAX) {
+ new_mem = mempool_alloc(&trans->c->btree_trans_mem_pool, GFP_KERNEL);
+ new_bytes = BTREE_TRANS_MEM_MAX;
+ kfree(trans->mem);
+ }
if (!new_mem)
return ERR_PTR(-ENOMEM);
trans->mem_bytes = new_bytes;
if (old_bytes) {
- trans_restart();
+ trace_trans_restart_mem_realloced(trans->ip, _RET_IP_, new_bytes);
return ERR_PTR(-EINTR);
}
}
- ret = trans->mem + trans->mem_top;
+ p = trans->mem + trans->mem_top;
trans->mem_top += size;
- return ret;
-}
-
-int bch2_trans_unlock(struct btree_trans *trans)
-{
- u64 iters = trans->iters_linked;
- int ret = 0;
-
- while (iters) {
- unsigned idx = __ffs64(iters);
- struct btree_iter *iter = &trans->iters[idx];
-
- ret = ret ?: btree_iter_err(iter);
-
- __bch2_btree_iter_unlock(iter);
- iters ^= 1ULL << idx;
- }
-
- return ret;
+ memset(p, 0, size);
+ return p;
}
-inline void bch2_trans_unlink_iters(struct btree_trans *trans, u64 iters)
+inline void bch2_trans_unlink_iters(struct btree_trans *trans)
{
- iters &= trans->iters_linked;
- iters &= ~trans->iters_live;
+ u64 iters = trans->iters_linked &
+ ~trans->iters_touched &
+ ~trans->iters_live;
while (iters) {
unsigned idx = __ffs64(iters);
}
}
-void __bch2_trans_begin(struct btree_trans *trans)
+void bch2_trans_reset(struct btree_trans *trans, unsigned flags)
{
- u64 iters_to_unlink;
-
- /*
- * On transaction restart, the transaction isn't required to allocate
- * all the same iterators it on the last iteration:
- *
- * Unlink any iterators it didn't use this iteration, assuming it got
- * further (allocated an iter with a higher idx) than where the iter
- * was originally allocated:
- */
- iters_to_unlink = ~trans->iters_live &
- ((1ULL << fls64(trans->iters_live)) - 1);
+ struct btree_iter *iter;
- iters_to_unlink |= trans->iters_unlink_on_restart;
- iters_to_unlink |= trans->iters_unlink_on_commit;
+ trans_for_each_iter(trans, iter) {
+ iter->flags &= ~(BTREE_ITER_KEEP_UNTIL_COMMIT|
+ BTREE_ITER_SET_POS_AFTER_COMMIT);
+ iter->should_be_locked = false;
+ }
- trans->iters_live = 0;
+ bch2_trans_unlink_iters(trans);
- bch2_trans_unlink_iters(trans, iters_to_unlink);
+ trans->iters_touched &= trans->iters_live;
- trans->iters_touched = 0;
- trans->iters_unlink_on_restart = 0;
- trans->iters_unlink_on_commit = 0;
+ trans->extra_journal_res = 0;
trans->nr_updates = 0;
trans->mem_top = 0;
- bch2_btree_iter_traverse_all(trans);
+ trans->hooks = NULL;
+ trans->extra_journal_entries = NULL;
+ trans->extra_journal_entry_u64s = 0;
+
+ if (trans->fs_usage_deltas) {
+ trans->fs_usage_deltas->used = 0;
+ memset(&trans->fs_usage_deltas->memset_start, 0,
+ (void *) &trans->fs_usage_deltas->memset_end -
+ (void *) &trans->fs_usage_deltas->memset_start);
+ }
+
+ if (!(flags & TRANS_RESET_NOUNLOCK))
+ bch2_trans_cond_resched(trans);
+
+ if (!(flags & TRANS_RESET_NOTRAVERSE) &&
+ trans->iters_linked)
+ bch2_btree_iter_traverse_all(trans);
}
-void bch2_trans_init(struct btree_trans *trans, struct bch_fs *c)
+static void bch2_trans_alloc_iters(struct btree_trans *trans, struct bch_fs *c)
{
- memset(trans, 0, offsetof(struct btree_trans, iters_onstack));
+ size_t iters_bytes = sizeof(struct btree_iter) * BTREE_ITER_MAX;
+ size_t updates_bytes = sizeof(struct btree_insert_entry) * BTREE_ITER_MAX;
+ void *p = NULL;
+
+ BUG_ON(trans->used_mempool);
+
+#ifdef __KERNEL__
+ p = this_cpu_xchg(c->btree_iters_bufs->iter, NULL);
+#endif
+ if (!p)
+ p = mempool_alloc(&trans->c->btree_iters_pool, GFP_NOFS);
+ trans->iters = p; p += iters_bytes;
+ trans->updates = p; p += updates_bytes;
+}
+
+void bch2_trans_init(struct btree_trans *trans, struct bch_fs *c,
+ unsigned expected_nr_iters,
+ size_t expected_mem_bytes)
+ __acquires(&c->btree_trans_barrier)
+{
+ memset(trans, 0, sizeof(*trans));
trans->c = c;
- trans->size = ARRAY_SIZE(trans->iters_onstack);
- trans->iters = trans->iters_onstack;
- trans->updates = trans->updates_onstack;
+ trans->ip = _RET_IP_;
+
+ /*
+ * reallocating iterators currently completely breaks
+ * bch2_trans_iter_put(), we always allocate the max:
+ */
+ bch2_trans_alloc_iters(trans, c);
+
+ if (expected_mem_bytes) {
+ trans->mem_bytes = roundup_pow_of_two(expected_mem_bytes);
+ trans->mem = kmalloc(trans->mem_bytes, GFP_KERNEL|__GFP_NOFAIL);
+
+ if (!unlikely(trans->mem)) {
+ trans->mem = mempool_alloc(&c->btree_trans_mem_pool, GFP_KERNEL);
+ trans->mem_bytes = BTREE_TRANS_MEM_MAX;
+ }
+ }
+
+ trans->srcu_idx = srcu_read_lock(&c->btree_trans_barrier);
+
+#ifdef CONFIG_BCACHEFS_DEBUG
+ trans->pid = current->pid;
+ mutex_lock(&c->btree_trans_lock);
+ list_add(&trans->list, &c->btree_trans_list);
+ mutex_unlock(&c->btree_trans_lock);
+#endif
}
int bch2_trans_exit(struct btree_trans *trans)
+ __releases(&c->btree_trans_barrier)
{
+ struct bch_fs *c = trans->c;
+
bch2_trans_unlock(trans);
- kfree(trans->mem);
- if (trans->used_mempool)
+#ifdef CONFIG_BCACHEFS_DEBUG
+ if (trans->iters_live) {
+ struct btree_iter *iter;
+
+ trans_for_each_iter(trans, iter)
+ btree_iter_child_free(iter);
+ }
+
+ if (trans->iters_live) {
+ struct btree_iter *iter;
+
+ bch_err(c, "btree iterators leaked!");
+ trans_for_each_iter(trans, iter)
+ if (btree_iter_live(trans, iter))
+ printk(KERN_ERR " btree %s allocated at %pS\n",
+ bch2_btree_ids[iter->btree_id],
+ (void *) iter->ip_allocated);
+ /* Be noisy about this: */
+ bch2_fatal_error(c);
+ }
+
+ mutex_lock(&trans->c->btree_trans_lock);
+ list_del(&trans->list);
+ mutex_unlock(&trans->c->btree_trans_lock);
+#endif
+
+ srcu_read_unlock(&c->btree_trans_barrier, trans->srcu_idx);
+
+ bch2_journal_preres_put(&trans->c->journal, &trans->journal_preres);
+
+ if (trans->fs_usage_deltas) {
+ if (trans->fs_usage_deltas->size + sizeof(trans->fs_usage_deltas) ==
+ REPLICAS_DELTA_LIST_MAX)
+ mempool_free(trans->fs_usage_deltas,
+ &trans->c->replicas_delta_pool);
+ else
+ kfree(trans->fs_usage_deltas);
+ }
+
+ if (trans->mem_bytes == BTREE_TRANS_MEM_MAX)
+ mempool_free(trans->mem, &trans->c->btree_trans_mem_pool);
+ else
+ kfree(trans->mem);
+
+#ifdef __KERNEL__
+ /*
+ * Userspace doesn't have a real percpu implementation:
+ */
+ trans->iters = this_cpu_xchg(c->btree_iters_bufs->iter, trans->iters);
+#endif
+
+ if (trans->iters)
mempool_free(trans->iters, &trans->c->btree_iters_pool);
- else if (trans->iters != trans->iters_onstack)
- kfree(trans->iters);
+
trans->mem = (void *) 0x1;
trans->iters = (void *) 0x1;
return trans->error ? -EIO : 0;
}
+
+static void __maybe_unused
+bch2_btree_iter_node_to_text(struct printbuf *out,
+ struct btree_bkey_cached_common *_b,
+ enum btree_iter_type type)
+{
+ pr_buf(out, " l=%u %s:",
+ _b->level, bch2_btree_ids[_b->btree_id]);
+ bch2_bpos_to_text(out, btree_node_pos(_b, type));
+}
+
+#ifdef CONFIG_BCACHEFS_DEBUG
+static bool trans_has_btree_nodes_locked(struct btree_trans *trans)
+{
+ struct btree_iter *iter;
+
+ trans_for_each_iter(trans, iter)
+ if (btree_iter_type(iter) != BTREE_ITER_CACHED &&
+ iter->nodes_locked)
+ return true;
+ return false;
+}
+#endif
+
+void bch2_btree_trans_to_text(struct printbuf *out, struct bch_fs *c)
+{
+#ifdef CONFIG_BCACHEFS_DEBUG
+ struct btree_trans *trans;
+ struct btree_iter *iter;
+ struct btree *b;
+ unsigned l;
+
+ mutex_lock(&c->btree_trans_lock);
+ list_for_each_entry(trans, &c->btree_trans_list, list) {
+ if (!trans_has_btree_nodes_locked(trans))
+ continue;
+
+ pr_buf(out, "%i %ps\n", trans->pid, (void *) trans->ip);
+
+ trans_for_each_iter(trans, iter) {
+ if (!iter->nodes_locked)
+ continue;
+
+ pr_buf(out, " iter %u %c %s:",
+ iter->idx,
+ btree_iter_type(iter) == BTREE_ITER_CACHED ? 'c' : 'b',
+ bch2_btree_ids[iter->btree_id]);
+ bch2_bpos_to_text(out, iter->pos);
+ pr_buf(out, "\n");
+
+ for (l = 0; l < BTREE_MAX_DEPTH; l++) {
+ if (btree_node_locked(iter, l)) {
+ pr_buf(out, " %s l=%u ",
+ btree_node_intent_locked(iter, l) ? "i" : "r", l);
+ bch2_btree_iter_node_to_text(out,
+ (void *) iter->l[l].b,
+ btree_iter_type(iter));
+ pr_buf(out, "\n");
+ }
+ }
+ }
+
+ b = READ_ONCE(trans->locking);
+ if (b) {
+ iter = &trans->iters[trans->locking_iter_idx];
+ pr_buf(out, " locking iter %u %c l=%u %s:",
+ trans->locking_iter_idx,
+ btree_iter_type(iter) == BTREE_ITER_CACHED ? 'c' : 'b',
+ trans->locking_level,
+ bch2_btree_ids[trans->locking_btree_id]);
+ bch2_bpos_to_text(out, trans->locking_pos);
+
+ pr_buf(out, " node ");
+ bch2_btree_iter_node_to_text(out,
+ (void *) b,
+ btree_iter_type(iter));
+ pr_buf(out, "\n");
+ }
+ }
+ mutex_unlock(&c->btree_trans_lock);
+#endif
+}
+
+void bch2_fs_btree_iter_exit(struct bch_fs *c)
+{
+ mempool_exit(&c->btree_trans_mem_pool);
+ mempool_exit(&c->btree_iters_pool);
+ cleanup_srcu_struct(&c->btree_trans_barrier);
+}
+
+int bch2_fs_btree_iter_init(struct bch_fs *c)
+{
+ unsigned nr = BTREE_ITER_MAX;
+
+ INIT_LIST_HEAD(&c->btree_trans_list);
+ mutex_init(&c->btree_trans_lock);
+
+ return init_srcu_struct(&c->btree_trans_barrier) ?:
+ mempool_init_kmalloc_pool(&c->btree_iters_pool, 1,
+ sizeof(struct btree_iter) * nr +
+ sizeof(struct btree_insert_entry) * nr) ?:
+ mempool_init_kmalloc_pool(&c->btree_trans_mem_pool, 1,
+ BTREE_TRANS_MEM_MAX);
+}
projects / bcachefs-tools-debian / blobdiff