[PATCH v3 17/21] to_shrink_list(): call only if refcount is 0

From: Al Viro
Date: Fri Nov 24 2023 - 01:05:50 EST


The only thing it does if refcount is not zero is d_lru_del(); no
point, IMO, seeing that plain dput() does nothing of that sort...

Note that 2 of 3 current callers are guaranteed that refcount is 0.

Acked-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/dcache.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index 5284b02747cd..704676bf06fd 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -915,8 +915,7 @@ __must_hold(&dentry->d_lock)
if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) {
if (dentry->d_flags & DCACHE_LRU_LIST)
d_lru_del(dentry);
- if (!dentry->d_lockref.count)
- d_shrink_add(dentry, list);
+ d_shrink_add(dentry, list);
}
}

@@ -1115,10 +1114,8 @@ EXPORT_SYMBOL(d_prune_aliases);
static inline void shrink_kill(struct dentry *victim, struct list_head *list)
{
struct dentry *parent = victim->d_parent;
- if (parent != victim) {
- --parent->d_lockref.count;
+ if (parent != victim && !--parent->d_lockref.count)
to_shrink_list(parent, list);
- }
__dentry_kill(victim);
}

--
2.39.2