| #ifndef _ASM_POWERPC_MEMBARRIER_H | |
| #define _ASM_POWERPC_MEMBARRIER_H | |
| static inline void membarrier_arch_switch_mm(struct mm_struct *prev, | |
| struct mm_struct *next, | |
| struct task_struct *tsk) | |
| { | |
| /* | |
| * Only need the full barrier when switching between processes. | |
| * Barrier when switching from kernel to userspace is not | |
| * required here, given that it is implied by mmdrop(). Barrier | |
| * when switching from userspace to kernel is not needed after | |
| * store to rq->curr. | |
| */ | |
| if (likely(!(atomic_read(&next->membarrier_state) & | |
| (MEMBARRIER_STATE_PRIVATE_EXPEDITED | | |
| MEMBARRIER_STATE_GLOBAL_EXPEDITED)) || !prev)) | |
| return; | |
| /* | |
| * The membarrier system call requires a full memory barrier | |
| * after storing to rq->curr, before going back to user-space. | |
| */ | |
| smp_mb(); | |
| } | |
| #endif /* _ASM_POWERPC_MEMBARRIER_H */ |