#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 */