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| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-11-24 09:53:11 (GMT) |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-12-18 08:54:40 (GMT) |
| commit | af2e7aaed1ccf30e61af3e096ac2c7df2f2d6c2a (patch) | |
| tree | 6e9e15b79431ca3f4be281e98491b86205f1fa7f /arch/arm64/include | |
| parent | 4218091cb45f601b889cd032e39fe6878a426e70 (diff) | |
| download | linux-af2e7aaed1ccf30e61af3e096ac2c7df2f2d6c2a.tar.xz | |
arm64/spinlock: Replace ACCESS_ONCE READ_ONCE
ACCESS_ONCE does not work reliably on non-scalar types. For
example gcc 4.6 and 4.7 might remove the volatile tag for such
accesses during the SRA (scalar replacement of aggregates) step
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)
Change the spinlock code to replace ACCESS_ONCE with READ_ONCE.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'arch/arm64/include')
| -rw-r--r-- | arch/arm64/include/asm/spinlock.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/spinlock.h b/arch/arm64/include/asm/spinlock.h index c45b7b1..cee1287 100644 --- a/arch/arm64/include/asm/spinlock.h +++ b/arch/arm64/include/asm/spinlock.h @@ -99,12 +99,12 @@ static inline int arch_spin_value_unlocked(arch_spinlock_t lock) static inline int arch_spin_is_locked(arch_spinlock_t *lock) { - return !arch_spin_value_unlocked(ACCESS_ONCE(*lock)); + return !arch_spin_value_unlocked(READ_ONCE(*lock)); } static inline int arch_spin_is_contended(arch_spinlock_t *lock) { - arch_spinlock_t lockval = ACCESS_ONCE(*lock); + arch_spinlock_t lockval = READ_ONCE(*lock); return (lockval.next - lockval.owner) > 1; } #define arch_spin_is_contended arch_spin_is_contended |