diff options
Diffstat (limited to 'include/asm-generic')
| -rw-r--r-- | include/asm-generic/qspinlock_types.h | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/include/asm-generic/qspinlock_types.h b/include/asm-generic/qspinlock_types.h index 034acd0c4956..6503e96710fa 100644 --- a/include/asm-generic/qspinlock_types.h +++ b/include/asm-generic/qspinlock_types.h @@ -18,6 +18,8 @@ #ifndef __ASM_GENERIC_QSPINLOCK_TYPES_H #define __ASM_GENERIC_QSPINLOCK_TYPES_H +#include <asm/byteorder.h> + /* * Including atomic.h with PARAVIRT on will cause compilation errors because * of recursive header file incluson via paravirt_types.h. So don't include @@ -29,13 +31,41 @@ #endif typedef struct qspinlock { - atomic_t val; + union { + atomic_t val; + + /* + * By using the whole 2nd least significant byte for the + * pending bit, we can allow better optimization of the lock + * acquisition for the pending bit holder. + */ +#ifdef __LITTLE_ENDIAN + struct { + u8 locked; + u8 pending; + }; + struct { + u16 locked_pending; + u16 tail; + }; +#else + struct { + u16 tail; + u16 locked_pending; + }; + struct { + u8 reserved[2]; + u8 pending; + u8 locked; + }; +#endif + }; } arch_spinlock_t; /* * Initializier */ -#define __ARCH_SPIN_LOCK_UNLOCKED { ATOMIC_INIT(0) } +#define __ARCH_SPIN_LOCK_UNLOCKED { { .val = ATOMIC_INIT(0) } } /* * Bitfields in the atomic value: |