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bcachefs: Kill normalize_read_intent_locks()

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Before we had the deadlock cycle detector, we didn't want to be holding
read locks when taking intent locks, because blocking on an intent lock
while holding a read lock was a lock ordering violation that could
cause a deadlock.

With the cycle detector this is no longer an issue, so this code can be
deleted.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
This commit is contained in:
Kent Overstreet 2022-08-22 15:29:53 -04:00 committed by Kent Overstreet
parent 2ec254c098
commit 8b31e4fc7d
1 changed files with 0 additions and 58 deletions
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58
fs/bcachefs/btree_update_leaf.c
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@ -740,62 +740,6 @@ bch2_trans_commit_write_locked(struct btree_trans *trans,
return ret;
}
static inline void path_upgrade_readers(struct btree_trans *trans, struct btree_path *path)
{
unsigned l;
for (l = 0; l < BTREE_MAX_DEPTH; l++)
if (btree_node_read_locked(path, l))
BUG_ON(!bch2_btree_node_upgrade(trans, path, l));
}
static inline void upgrade_readers(struct btree_trans *trans, struct btree_path *path)
{
struct btree *b = path_l(path)->b;
unsigned l;
do {
for (l = 0; l < BTREE_MAX_DEPTH; l++)
if (btree_node_read_locked(path, l))
path_upgrade_readers(trans, path);
} while ((path = prev_btree_path(trans, path)) &&
path_l(path)->b == b);
}
/*
* Check for nodes that we have both read and intent locks on, and upgrade the
* readers to intent:
*/
static inline void normalize_read_intent_locks(struct btree_trans *trans)
{
struct btree_path *path;
unsigned i, nr_read = 0, nr_intent = 0;
trans_for_each_path_inorder(trans, path, i) {
struct btree_path *next = i + 1 < trans->nr_sorted
? trans->paths + trans->sorted[i + 1]
: NULL;
switch (btree_node_locked_type(path, path->level)) {
case BTREE_NODE_READ_LOCKED:
nr_read++;
break;
case BTREE_NODE_INTENT_LOCKED:
nr_intent++;
break;
}
if (!next || path_l(path)->b != path_l(next)->b) {
if (nr_read && nr_intent)
upgrade_readers(trans, path);
nr_read = nr_intent = 0;
}
}
bch2_trans_verify_locks(trans);
}
static inline int trans_lock_write(struct btree_trans *trans)
{
struct btree_insert_entry *i;
@ -899,8 +843,6 @@ static inline int do_bch2_trans_commit(struct btree_trans *trans,
if (unlikely(ret))
return ret;
normalize_read_intent_locks(trans);
ret = trans_lock_write(trans);
if (unlikely(ret))
return ret;