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authorFelipe Balbi <balbi@ti.com>2013-12-23 12:22:46 -0500
committerFelipe Balbi <balbi@ti.com>2013-12-23 12:22:46 -0500
commite90b8417af0d01cf8c64da6937c914c89ccf6dc1 (patch)
treecbc5e3b975b2efbb786e12b91714f8c3c3979316 /drivers/tty/tty_ldsem.c
parent845c071b7853c0046693022f4e95c9cdd043e2db (diff)
parent413541dd66d51f791a0b169d9b9014e4f56be13c (diff)
Merge tag 'v3.13-rc5' into next
Linux 3.13-rc5 * tag 'v3.13-rc5': (231 commits) Linux 3.13-rc5 aio: clean up and fix aio_setup_ring page mapping aio/migratepages: make aio migrate pages sane aio: fix kioctx leak introduced by "aio: Fix a trinity splat" Don't set the INITRD_COMPRESS environment variable automatically mm: fix build of split ptlock code pstore: Don't allow high traffic options on fragile devices mm: do not allocate page->ptl dynamically, if spinlock_t fits to long mm: page_alloc: revert NUMA aspect of fair allocation policy Revert "mm: page_alloc: exclude unreclaimable allocations from zone fairness policy" mm: Fix NULL pointer dereference in madvise(MADV_WILLNEED) support qla2xxx: Fix scsi_host leak on qlt_lport_register callback failure target: Remove extra percpu_ref_init arm64: ptrace: avoid using HW_BREAKPOINT_EMPTY for disabled events ARC: Allow conditional multiple inclusion of uapi/asm/unistd.h target/file: Update hw_max_sectors based on current block_size iser-target: Move INIT_WORK setup into isert_create_device_ib_res iscsi-target: Fix incorrect np->np_thread NULL assignment mm/hugetlb: check for pte NULL pointer in __page_check_address() fix build with make 3.80 ... Conflicts: drivers/usb/phy/Kconfig
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/*