[PATCH 1/3] fold d_kill() and d_free()

From: Al Viro
Date: Tue Apr 29 2014 - 15:45:28 EST


Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/dcache.c | 76 +++++++++++++++++++----------------------------------------
1 file changed, 24 insertions(+), 52 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index 494a9def..9b15c5c 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -246,23 +246,6 @@ static void __d_free(struct rcu_head *head)
kmem_cache_free(dentry_cache, dentry);
}

-/*
- * no locks, please.
- */
-static void d_free(struct dentry *dentry)
-{
- BUG_ON((int)dentry->d_lockref.count > 0);
- this_cpu_dec(nr_dentry);
- if (dentry->d_op && dentry->d_op->d_release)
- dentry->d_op->d_release(dentry);
-
- /* if dentry was never visible to RCU, immediate free is OK */
- if (!(dentry->d_flags & DCACHE_RCUACCESS))
- __d_free(&dentry->d_u.d_rcu);
- else
- call_rcu(&dentry->d_u.d_rcu, __d_free);
-}
-
/**
* dentry_rcuwalk_barrier - invalidate in-progress rcu-walk lookups
* @dentry: the target dentry
@@ -420,40 +403,6 @@ static void dentry_lru_del(struct dentry *dentry)
}

/**
- * d_kill - kill dentry and return parent
- * @dentry: dentry to kill
- * @parent: parent dentry
- *
- * The dentry must already be unhashed and removed from the LRU.
- *
- * If this is the root of the dentry tree, return NULL.
- *
- * dentry->d_lock and parent->d_lock must be held by caller, and are dropped by
- * d_kill.
- */
-static struct dentry *d_kill(struct dentry *dentry, struct dentry *parent)
- __releases(dentry->d_lock)
- __releases(parent->d_lock)
- __releases(dentry->d_inode->i_lock)
-{
- list_del(&dentry->d_u.d_child);
- /*
- * Inform d_walk() that we are no longer attached to the
- * dentry tree
- */
- dentry->d_flags |= DCACHE_DENTRY_KILLED;
- if (parent)
- spin_unlock(&parent->d_lock);
- dentry_iput(dentry);
- /*
- * dentry_iput drops the locks, at which point nobody (except
- * transient RCU lookups) can reach this dentry.
- */
- d_free(dentry);
- return parent;
-}
-
-/**
* d_drop - drop a dentry
* @dentry: dentry to drop
*
@@ -546,7 +495,30 @@ relock:
dentry_lru_del(dentry);
/* if it was on the hash then remove it */
__d_drop(dentry);
- return d_kill(dentry, parent);
+ list_del(&dentry->d_u.d_child);
+ /*
+ * Inform d_walk() that we are no longer attached to the
+ * dentry tree
+ */
+ dentry->d_flags |= DCACHE_DENTRY_KILLED;
+ if (parent)
+ spin_unlock(&parent->d_lock);
+ dentry_iput(dentry);
+ /*
+ * dentry_iput drops the locks, at which point nobody (except
+ * transient RCU lookups) can reach this dentry.
+ */
+ BUG_ON((int)dentry->d_lockref.count > 0);
+ this_cpu_dec(nr_dentry);
+ if (dentry->d_op && dentry->d_op->d_release)
+ dentry->d_op->d_release(dentry);
+
+ /* if dentry was never visible to RCU, immediate free is OK */
+ if (!(dentry->d_flags & DCACHE_RCUACCESS))
+ __d_free(&dentry->d_u.d_rcu);
+ else
+ call_rcu(&dentry->d_u.d_rcu, __d_free);
+ return parent;
}

/*
--
1.7.10.4