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author | Sage Weil <sage@inktank.com> | 2013-08-15 11:11:45 -0700 |
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committer | Sage Weil <sage@inktank.com> | 2013-08-15 11:11:45 -0700 |
commit | ee3e542fec6e69bc9fb668698889a37d93950ddf (patch) | |
tree | e74ee766a4764769ef1d3d45d266b4dea64101d3 /arch/arm64/include/asm/sync_bitops.h | |
parent | fe2a801b50c0bb8039d627e5ae1fec249d10ff39 (diff) | |
parent | f1d6e17f540af37bb1891480143669ba7636c4cf (diff) |
Merge remote-tracking branch 'linus/master' into testing
Diffstat (limited to 'arch/arm64/include/asm/sync_bitops.h')
-rw-r--r-- | arch/arm64/include/asm/sync_bitops.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/sync_bitops.h b/arch/arm64/include/asm/sync_bitops.h new file mode 100644 index 00000000000..8da0bf4f765 --- /dev/null +++ b/arch/arm64/include/asm/sync_bitops.h @@ -0,0 +1,26 @@ +#ifndef __ASM_SYNC_BITOPS_H__ +#define __ASM_SYNC_BITOPS_H__ + +#include <asm/bitops.h> +#include <asm/cmpxchg.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 |