diff options
| author | John David Anglin <dave.anglin@bell.net> | 2018-10-17 04:07:59 +0300 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2018-10-17 09:18:01 +0300 |
| commit | d27dfa13b9f77ae7e6ed09d70a0426ed26c1a8f9 (patch) | |
| tree | c5cf891ba797b92a699bc6c3da95016ffc057c88 /arch/parisc/include/asm/spinlock.h | |
| parent | 2e37787df0ed0047848dba2eba53510a9185b991 (diff) | |
| download | linux-d27dfa13b9f77ae7e6ed09d70a0426ed26c1a8f9.tar.xz | |
parisc: Release spinlocks using ordered store
This patch updates the spin unlock code to use an ordered store with
release semanatics. All prior accesses are guaranteed to be performed
before an ordered store is performed.
Using an ordered store is significantly faster than using the sync
memory barrier.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc/include/asm/spinlock.h')
| -rw-r--r-- | arch/parisc/include/asm/spinlock.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/parisc/include/asm/spinlock.h b/arch/parisc/include/asm/spinlock.h index 8a63515f03bf..16aec9ba2580 100644 --- a/arch/parisc/include/asm/spinlock.h +++ b/arch/parisc/include/asm/spinlock.h @@ -37,8 +37,8 @@ static inline void arch_spin_unlock(arch_spinlock_t *x) volatile unsigned int *a; a = __ldcw_align(x); - mb(); - *a = 1; + /* Release with ordered store. */ + __asm__ __volatile__("stw,ma %0,0(%1)" : : "r"(1), "r"(a) : "memory"); } static inline int arch_spin_trylock(arch_spinlock_t *x) |