[tip:timers/core] seqcount: Rename write_seqcount_barrier()

tip-bot for Peter Zijlstra
2015-06-18T22:20:04Z

Commit-ID: a7c6f571ff51cc77d90dd54968f7c5c938c43998
Gitweb: http://git.kernel.org/tip/a7c6f571ff51cc77d90dd54968f7c5c938c43998
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Thu, 11 Jun 2015 14:46:46 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Fri, 19 Jun 2015 00:09:56 +0200

seqcount: Rename write_seqcount_barrier()

I'll shortly be introducing another seqcount primitive that's useful
to provide ordering semantics and would like to use the
write_seqcount_barrier() name for that.

Seeing how there's only one user of the current primitive, lets rename
it to invalidate, as that appears what its doing.

While there, employ lockdep_assert_held() instead of
assert_spin_locked() to not generate debug code for regular kernels.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: ktkhai@parallels.com
Cc: rostedt@goodmis.org
Cc: juri.lelli@gmail.com
Cc: pang.xunlei@linaro.org
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: wanpeng.li@linux.intel.com
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: umgwanakikbuti@gmail.com
Link: http://lkml.kernel.org/r/20150611124743.279926217@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
fs/dcache.c | 16 ++++++++--------
include/linux/seqlock.h | 6 +++---
2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/fs/dcache.c b/fs/dcache.c
index 656ce52..b43a169 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -322,17 +322,17 @@ static void dentry_free(struct dentry *dentry)
}

/**
- * dentry_rcuwalk_barrier - invalidate in-progress rcu-walk lookups
+ * dentry_rcuwalk_invalidate - invalidate in-progress rcu-walk lookups
* @dentry: the target dentry
* After this call, in-progress rcu-walk path lookup will fail. This
* should be called after unhashing, and after changing d_inode (if
* the dentry has not already been unhashed).
*/
-static inline void dentry_rcuwalk_barrier(struct dentry *dentry)
+static inline void dentry_rcuwalk_invalidate(struct dentry *dentry)
{
- assert_spin_locked(&dentry->d_lock);
- /* Go through a barrier */
- write_seqcount_barrier(&dentry->d_seq);
+ lockdep_assert_held(&dentry->d_lock);
+ /* Go through am invalidation barrier */
+ write_seqcount_invalidate(&dentry->d_seq);
}

/*
@@ -372,7 +372,7 @@ static void dentry_unlink_inode(struct dentry * dentry)
struct inode *inode = dentry->d_inode;
__d_clear_type_and_inode(dentry);
hlist_del_init(&dentry->d_u.d_alias);
- dentry_rcuwalk_barrier(dentry);
+ dentry_rcuwalk_invalidate(dentry);
spin_unlock(&dentry->d_lock);
spin_unlock(&inode->i_lock);
if (!inode->i_nlink)
@@ -494,7 +494,7 @@ void __d_drop(struct dentry *dentry)
__hlist_bl_del(&dentry->d_hash);
dentry->d_hash.pprev = NULL;
hlist_bl_unlock(b);
- dentry_rcuwalk_barrier(dentry);
+ dentry_rcuwalk_invalidate(dentry);
}
}
EXPORT_SYMBOL(__d_drop);
@@ -1752,7 +1752,7 @@ static void __d_instantiate(struct dentry *dentry, struct inode *inode)
if (inode)
hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry);
__d_set_inode_and_type(dentry, inode, add_flags);
- dentry_rcuwalk_barrier(dentry);
+ dentry_rcuwalk_invalidate(dentry);
spin_unlock(&dentry->d_lock);
fsnotify_d_instantiate(dentry, inode);
}
diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 5f68d0a..c07e3a5 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -266,13 +266,13 @@ static inline void write_seqcount_end(seqcount_t *s)
}

/**
- * write_seqcount_barrier - invalidate in-progress read-side seq operations
+ * write_seqcount_invalidate - invalidate in-progress read-side seq operations
* @s: pointer to seqcount_t
*
- * After write_seqcount_barrier, no read-side seq operations will complete
+ * After write_seqcount_invalidate, no read-side seq operations will complete
* successfully and see data older than this.
*/
-static inline void write_seqcount_barrier(seqcount_t *s)
+static inline void write_seqcount_invalidate(seqcount_t *s)
{
smp_wmb();
s->sequence+=2;