[PATCH] convert hugetlbfs_counter to atomic

Implementation of hugetlbfs_counter() is functionally equivalent to
atomic_inc_return().  Use the simpler atomic form.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 1a1c2fc..25fa8bb 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -737,21 +737,6 @@ static struct file_system_type hugetlbfs_fs_type = {
 
 static struct vfsmount *hugetlbfs_vfsmount;
 
-/*
- * Return the next identifier for a shm file
- */
-static unsigned long hugetlbfs_counter(void)
-{
-       static DEFINE_SPINLOCK(lock);
-       static unsigned long counter;
-       unsigned long ret;
-
-       spin_lock(&lock);
-       ret = ++counter;
-       spin_unlock(&lock);
-       return ret;
-}
-
 static int can_do_hugetlb_shm(void)
 {
        return likely(capable(CAP_IPC_LOCK) ||
@@ -767,6 +752,7 @@ struct file *hugetlb_zero_setup(size_t size)
        struct dentry *dentry, *root;
        struct qstr quick_string;
        char buf[16];
+       static atomic_t counter;
 
        if (!can_do_hugetlb_shm())
                return ERR_PTR(-EPERM);
@@ -775,7 +761,7 @@ struct file *hugetlb_zero_setup(size_t size)
                return ERR_PTR(-ENOMEM);
 
        root = hugetlbfs_vfsmount->mnt_root;
-       snprintf(buf, 16, "%lu", hugetlbfs_counter());
+       snprintf(buf, 16, "%u", atomic_inc_return(&counter));
        quick_string.name = buf;
        quick_string.len = strlen(quick_string.name);
        quick_string.hash = 0;