diff options
| -rw-r--r-- | fs/dcache.c | 29 |
1 files changed, 12 insertions, 17 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 94749442fa68..beb0523c3304 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2743,38 +2743,33 @@ struct dentry *d_alloc_parallel(struct dentry *parent, spin_unlock(&parent->d_lock); retry: - rcu_read_lock(); seq = smp_load_acquire(&parent->d_inode->i_dir_seq); r_seq = read_seqbegin(&rename_lock); + rcu_read_lock(); dentry = __d_lookup_rcu(parent, name, &d_seq); if (unlikely(dentry)) { if (!lockref_get_not_dead(&dentry->d_lockref)) { rcu_read_unlock(); goto retry; } + rcu_read_unlock(); if (read_seqcount_retry(&dentry->d_seq, d_seq)) { - rcu_read_unlock(); dput(dentry); goto retry; } - rcu_read_unlock(); dput(new); return dentry; } - if (unlikely(read_seqretry(&rename_lock, r_seq))) { - rcu_read_unlock(); + rcu_read_unlock(); + if (unlikely(read_seqretry(&rename_lock, r_seq))) goto retry; - } - if (unlikely(seq & 1)) { - rcu_read_unlock(); + if (unlikely(seq & 1)) goto retry; - } hlist_bl_lock(b); if (unlikely(READ_ONCE(parent->d_inode->i_dir_seq) != seq)) { hlist_bl_unlock(b); - rcu_read_unlock(); goto retry; } /* @@ -2791,19 +2786,20 @@ retry: continue; if (!d_same_name(dentry, parent, name)) continue; + rcu_read_lock(); hlist_bl_unlock(b); + spin_lock(&dentry->d_lock); + rcu_read_unlock(); /* now we can try to grab a reference */ - if (!lockref_get_not_dead(&dentry->d_lockref)) { - rcu_read_unlock(); + if (unlikely(dentry->d_lockref.count < 0)) { + spin_unlock(&dentry->d_lock); goto retry; } - - rcu_read_unlock(); /* * somebody is likely to be still doing lookup for it; - * wait for them to finish + * pin it and wait for them to finish */ - spin_lock(&dentry->d_lock); + dget_dlock(dentry); d_wait_lookup(dentry); /* * it's not in-lookup anymore; in principle we should repeat @@ -2824,7 +2820,6 @@ retry: dput(new); return dentry; } - rcu_read_unlock(); hlist_bl_add_head(&new->d_in_lookup_hash, b); hlist_bl_unlock(b); return new; |