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authorOlof Johansson <olof@lixom.net>2013-12-29 00:37:03 -0500
committerOlof Johansson <olof@lixom.net>2013-12-29 00:38:16 -0500
commitfe5a365cdb9cc925d5ce86a5bb4509dca57f3894 (patch)
tree8dd536be0e16e86109295142edd1ef1fd18c2e98 /drivers/tty/tty_ldsem.c
parent4d77ce6c1fcae189dcd6fb0c7342f1c901b50a70 (diff)
parent413541dd66d51f791a0b169d9b9014e4f56be13c (diff)
Merge tag 'v3.13-rc5' into next/boards
Need a newer base version to get a regulator fix for Samsung platforms that they enable building in a defconfig. Linux 3.13-rc5
Diffstat (limited to 'drivers/tty/tty_ldsem.c')
-rw-r--r--drivers/tty/tty_ldsem.c16
1 files changed, 13 insertions, 3 deletions
diff --git a/drivers/tty/tty_ldsem.c b/drivers/tty/tty_ldsem.c
index 22fad8ad5ac2..d8a55e87877f 100644
--- a/drivers/tty/tty_ldsem.c
+++ b/drivers/tty/tty_ldsem.c
@@ -86,11 +86,21 @@ static inline long ldsem_atomic_update(long delta, struct ld_semaphore *sem)
86 return atomic_long_add_return(delta, (atomic_long_t *)&sem->count); 86 return atomic_long_add_return(delta, (atomic_long_t *)&sem->count);
87} 87}
88 88
89/*
90 * ldsem_cmpxchg() updates @*old with the last-known sem->count value.
91 * Returns 1 if count was successfully changed; @*old will have @new value.
92 * Returns 0 if count was not changed; @*old will have most recent sem->count
93 */
89static inline int ldsem_cmpxchg(long *old, long new, struct ld_semaphore *sem) 94static inline int ldsem_cmpxchg(long *old, long new, struct ld_semaphore *sem)
90{ 95{
91 long tmp = *old; 96 long tmp = atomic_long_cmpxchg(&sem->count, *old, new);
92 *old = atomic_long_cmpxchg(&sem->count, *old, new); 97 if (tmp == *old) {
93 return *old == tmp; 98 *old = new;
99 return 1;
100 } else {
101 *old = tmp;
102 return 0;
103 }
94} 104}
95 105
96/* 106/*