51 lines
1.5 KiB
Diff
51 lines
1.5 KiB
Diff
From: Al Viro <viro@zeniv.linux.org.uk>
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Date: Fri, 23 Feb 2018 22:11:34 -0500
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Subject: [PATCH 03/17] split the slow part of lock_parent() off
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Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.16/older/patches-4.16.7-rt1.tar.xz
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Upstream commit 8b987a46a1e0e93d4cb4babea06ea274e2e2b658
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Turn the "trylock failed" part into uninlined __lock_parent().
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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fs/dcache.c | 18 ++++++++++++------
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1 file changed, 12 insertions(+), 6 deletions(-)
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--- a/fs/dcache.c
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+++ b/fs/dcache.c
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@@ -588,13 +588,9 @@ static void __dentry_kill(struct dentry
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dentry_free(dentry);
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}
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-static inline struct dentry *lock_parent(struct dentry *dentry)
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+static struct dentry *__lock_parent(struct dentry *dentry)
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{
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- struct dentry *parent = dentry->d_parent;
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- if (IS_ROOT(dentry))
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- return NULL;
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- if (likely(spin_trylock(&parent->d_lock)))
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- return parent;
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+ struct dentry *parent;
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rcu_read_lock();
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spin_unlock(&dentry->d_lock);
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again:
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@@ -620,6 +616,16 @@ static inline struct dentry *lock_parent
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return parent;
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}
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+static inline struct dentry *lock_parent(struct dentry *dentry)
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+{
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+ struct dentry *parent = dentry->d_parent;
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+ if (IS_ROOT(dentry))
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+ return NULL;
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+ if (likely(spin_trylock(&parent->d_lock)))
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+ return parent;
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+ return __lock_parent(dentry);
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+}
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+
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/*
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* Finish off a dentry we've decided to kill.
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* dentry->d_lock must be held, returns with it unlocked.
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