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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-10-11 10:55:04 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2012-10-11 10:55:04 +0100 |
| commit | a0f0dd57f4a85310d9936f1770a0424b49fef876 (patch) | |
| tree | 2f85b8b67dda13d19b02ca39e0fbef921cb1cf8b /arch/arm/include/asm/sync_bitops.h | |
| parent | 2a552d5e63d7fa602c9a9a0717008737f55625a6 (diff) | |
| parent | 846a136881b8f73c1f74250bf6acfaa309cab1f2 (diff) | |
Merge branch 'fixes' into for-linus
Conflicts:
arch/arm/kernel/smp.c
Diffstat (limited to 'arch/arm/include/asm/sync_bitops.h')
| -rw-r--r-- | arch/arm/include/asm/sync_bitops.h | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/arch/arm/include/asm/sync_bitops.h b/arch/arm/include/asm/sync_bitops.h new file mode 100644 index 00000000000..63479eecbf7 --- /dev/null +++ b/arch/arm/include/asm/sync_bitops.h @@ -0,0 +1,27 @@ +#ifndef __ASM_SYNC_BITOPS_H__ +#define __ASM_SYNC_BITOPS_H__ + +#include <asm/bitops.h> +#include <asm/system.h> + +/* sync_bitops functions are equivalent to the SMP implementation of the + * original functions, independently from CONFIG_SMP being defined. + * + * We need them because _set_bit etc are not SMP safe if !CONFIG_SMP. But + * under Xen you might be communicating with a completely external entity + * who might be on another CPU (e.g. two uniprocessor guests communicating + * via event channels and grant tables). So we need a variant of the bit + * ops which are SMP safe even on a UP kernel. + */ + +#define sync_set_bit(nr, p) _set_bit(nr, p) +#define sync_clear_bit(nr, p) _clear_bit(nr, p) +#define sync_change_bit(nr, p) _change_bit(nr, p) +#define sync_test_and_set_bit(nr, p) _test_and_set_bit(nr, p) +#define sync_test_and_clear_bit(nr, p) _test_and_clear_bit(nr, p) +#define sync_test_and_change_bit(nr, p) _test_and_change_bit(nr, p) +#define sync_test_bit(nr, addr) test_bit(nr, addr) +#define sync_cmpxchg cmpxchg + + +#endif |