diff options
author | Will Deacon <will.deacon@arm.com> | 2013-08-12 13:03:26 -0400 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-08-13 15:22:43 -0400 |
commit | afa31d8eb86fc2f25083e675d57ac8173a98f999 (patch) | |
tree | b266adc9aebcda0a7eccd7adbd07a4a5aab3ceee /arch | |
parent | e35ac62d2202e31307c0f9b278a61e484c4727f2 (diff) |
ARM: 7811/1: locks: use early clobber in arch_spin_trylock
The res variable is written before we've finished with the input
operands (namely the lock address), so ensure that we mark it as `early
clobber' to avoid unintended register sharing.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm/include/asm/spinlock.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h index f8b8965666e9..7ed43f68e044 100644 --- a/arch/arm/include/asm/spinlock.h +++ b/arch/arm/include/asm/spinlock.h | |||
@@ -107,7 +107,7 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock) | |||
107 | " subs %1, %0, %0, ror #16\n" | 107 | " subs %1, %0, %0, ror #16\n" |
108 | " addeq %0, %0, %4\n" | 108 | " addeq %0, %0, %4\n" |
109 | " strexeq %2, %0, [%3]" | 109 | " strexeq %2, %0, [%3]" |
110 | : "=&r" (slock), "=&r" (contended), "=r" (res) | 110 | : "=&r" (slock), "=&r" (contended), "=&r" (res) |
111 | : "r" (&lock->slock), "I" (1 << TICKET_SHIFT) | 111 | : "r" (&lock->slock), "I" (1 << TICKET_SHIFT) |
112 | : "cc"); | 112 | : "cc"); |
113 | } while (res); | 113 | } while (res); |