/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _ASM_RISCV_MEMBARRIER_H
#define _ASM_RISCV_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 (IS_ENABLED(CONFIG_SMP) &&
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.
* Matches a full barrier in the proximity of the membarrier
* system call entry.
*/
smp_mb();
}
#endif /* _ASM_RISCV_MEMBARRIER_H */
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