From: John Ogness <john.ogness@linutronix.de>
To: linux-fsdevel@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>,
Linus Torvalds <torvalds@linux-foundation.org>,
Christoph Hellwig <hch@lst.de>,
Thomas Gleixner <tglx@linutronix.de>,
Peter Zijlstra <peterz@infradead.org>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
linux-kernel@vger.kernel.org
Subject: [PATCH 2/4] fs/dcache: Move dentry_kill() below lock_parent()
Date: Fri, 16 Feb 2018 16:09:31 +0100 [thread overview]
Message-ID: <20180216150933.971-3-john.ogness@linutronix.de> (raw)
In-Reply-To: <20180216150933.971-1-john.ogness@linutronix.de>
A subsequent patch will modify dentry_kill() to call lock_parent().
Move the dentry_kill() implementation "as is" below lock_parent()
first. This will help simplify the review of the subsequent patch
with dentry_kill() changes.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
---
fs/dcache.c | 62 ++++++++++++++++++++++++++++++-------------------------------
1 file changed, 31 insertions(+), 31 deletions(-)
diff --git a/fs/dcache.c b/fs/dcache.c
index 3c7e0148b453..9fed398687c9 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -589,37 +589,6 @@ static void __dentry_kill(struct dentry *dentry)
dentry_free(dentry);
}
-/*
- * Finish off a dentry we've decided to kill.
- * dentry->d_lock must be held, returns with it unlocked.
- * Returns dentry requiring refcount drop, or NULL if we're done.
- */
-static struct dentry *dentry_kill(struct dentry *dentry)
- __releases(dentry->d_lock)
-{
- struct inode *inode = dentry->d_inode;
- struct dentry *parent = NULL;
-
- if (inode && unlikely(!spin_trylock(&inode->i_lock)))
- goto failed;
-
- if (!IS_ROOT(dentry)) {
- parent = dentry->d_parent;
- if (unlikely(!spin_trylock(&parent->d_lock))) {
- if (inode)
- spin_unlock(&inode->i_lock);
- goto failed;
- }
- }
-
- __dentry_kill(dentry);
- return parent;
-
-failed:
- spin_unlock(&dentry->d_lock);
- return dentry; /* try again with same dentry */
-}
-
static inline struct dentry *lock_parent(struct dentry *dentry)
{
struct dentry *parent = dentry->d_parent;
@@ -655,6 +624,37 @@ static inline struct dentry *lock_parent(struct dentry *dentry)
}
/*
+ * Finish off a dentry we've decided to kill.
+ * dentry->d_lock must be held, returns with it unlocked.
+ * Returns dentry requiring refcount drop, or NULL if we're done.
+ */
+static struct dentry *dentry_kill(struct dentry *dentry)
+ __releases(dentry->d_lock)
+{
+ struct inode *inode = dentry->d_inode;
+ struct dentry *parent = NULL;
+
+ if (inode && unlikely(!spin_trylock(&inode->i_lock)))
+ goto failed;
+
+ if (!IS_ROOT(dentry)) {
+ parent = dentry->d_parent;
+ if (unlikely(!spin_trylock(&parent->d_lock))) {
+ if (inode)
+ spin_unlock(&inode->i_lock);
+ goto failed;
+ }
+ }
+
+ __dentry_kill(dentry);
+ return parent;
+
+failed:
+ spin_unlock(&dentry->d_lock);
+ return dentry; /* try again with same dentry */
+}
+
+/*
* Try to do a lockless dput(), and return whether that was successful.
*
* If unsuccessful, we return false, having already taken the dentry lock.
--
2.11.0
next prev parent reply other threads:[~2018-02-16 15:10 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-16 15:09 [PATCH 0/4] fs/dcache: avoid trylock loops John Ogness
2018-02-16 15:09 ` [PATCH 1/4] fs/dcache: Remove stale comment from dentry_kill() John Ogness
2018-02-16 15:09 ` John Ogness [this message]
2018-02-16 15:09 ` [PATCH 3/4] fs/dcache: Avoid the try_lock loop in d_delete() John Ogness
2018-02-16 17:10 ` Peter Zijlstra
2018-02-16 17:30 ` Peter Zijlstra
2018-02-22 5:18 ` Al Viro
2018-02-22 8:35 ` John Ogness
2018-02-16 15:09 ` [PATCH 4/4] fs/dcache: Avoid the try_lock loops in dentry_kill() John Ogness
2018-02-16 18:03 ` Linus Torvalds
2018-02-16 22:32 ` John Ogness
2018-02-16 22:42 ` Linus Torvalds
2018-02-16 23:05 ` John Ogness
2018-02-16 23:31 ` Linus Torvalds
2018-02-16 23:49 ` John Ogness
2018-02-17 0:06 ` Linus Torvalds
2018-02-19 23:34 ` John Ogness
2018-02-20 0:42 ` Linus Torvalds
2018-02-20 8:39 ` Peter Zijlstra
2018-02-20 8:43 ` Peter Zijlstra
2018-02-22 5:29 ` Al Viro
2018-02-22 5:40 ` Al Viro
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