1#ifndef _ASM_POWERPC_MEMBARRIER_H
2#define _ASM_POWERPC_MEMBARRIER_H
3
4static inline void membarrier_arch_switch_mm(struct mm_struct *prev,
5					     struct mm_struct *next,
6					     struct task_struct *tsk)
7{
8	/*
9	 * Only need the full barrier when switching between processes.
10	 * Barrier when switching from kernel to userspace is not
11	 * required here, given that it is implied by mmdrop(). Barrier
12	 * when switching from userspace to kernel is not needed after
13	 * store to rq->curr.
14	 */
15	if (likely(!(atomic_read(&next->membarrier_state) &
16		     (MEMBARRIER_STATE_PRIVATE_EXPEDITED |
17		      MEMBARRIER_STATE_GLOBAL_EXPEDITED)) || !prev))
18		return;
19
20	/*
21	 * The membarrier system call requires a full memory barrier
22	 * after storing to rq->curr, before going back to user-space.
23	 */
24	smp_mb();
25}
26
27#endif /* _ASM_POWERPC_MEMBARRIER_H */
28