diff options
| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-11-25 11:44:26 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-12-18 09:54:40 +0100 |
| commit | 488beef1440e845751365202faace2465840ea98 (patch) | |
| tree | f1ef574626d0253813e9436fe7a114cf48af19a5 | |
| parent | af2e7aaed1ccf30e61af3e096ac2c7df2f2d6c2a (diff) | |
| download | op-kernel-dev-488beef1440e845751365202faace2465840ea98.zip op-kernel-dev-488beef1440e845751365202faace2465840ea98.tar.gz | |
arm/spinlock: Replace ACCESS_ONCE with 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>
| -rw-r--r-- | arch/arm/include/asm/spinlock.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h index ac4bfae..0fa4184 100644 --- a/arch/arm/include/asm/spinlock.h +++ b/arch/arm/include/asm/spinlock.h @@ -120,12 +120,12 @@ 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) { - struct __raw_tickets tickets = ACCESS_ONCE(lock->tickets); + struct __raw_tickets tickets = READ_ONCE(lock->tickets); return (tickets.next - tickets.owner) > 1; } #define arch_spin_is_contended arch_spin_is_contended |
