cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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membarrier.h (877B)


      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 (IS_ENABLED(CONFIG_SMP) &&
     16	    likely(!(atomic_read(&next->membarrier_state) &
     17		     (MEMBARRIER_STATE_PRIVATE_EXPEDITED |
     18		      MEMBARRIER_STATE_GLOBAL_EXPEDITED)) || !prev))
     19		return;
     20
     21	/*
     22	 * The membarrier system call requires a full memory barrier
     23	 * after storing to rq->curr, before going back to user-space.
     24	 */
     25	smp_mb();
     26}
     27
     28#endif /* _ASM_POWERPC_MEMBARRIER_H */