LXR linux/arch/arm/include/asm/switch

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __ASM_ARM_SWITCH_TO_H
   3#define __ASM_ARM_SWITCH_TO_H
   4
   5#include <linux/thread_info.h>
   6
   7/*
   8 * For v7 SMP cores running a preemptible kernel we may be pre-empted
   9 * during a TLB maintenance operation, so execute an inner-shareable dsb
  10 * to ensure that the maintenance completes in case we migrate to another
  11 * CPU.
  12 */
  13#if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
  14#define __complete_pending_tlbi()       dsb(ish)
  15#else
  16#define __complete_pending_tlbi()
  17#endif
  18
  19/*
  20 * switch_to(prev, next) should switch from task `prev' to `next'
  21 * `prev' will never be the same as `next'.  schedule() itself
  22 * contains the memory barrier to tell GCC not to cache `current'.
  23 */
  24extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
  25
  26#define switch_to(prev,next,last)                                       \
  27do {                                                                    \
  28        __complete_pending_tlbi();                                      \
  29        last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));        \
  30} while (0)
  31
  32#endif /* __ASM_ARM_SWITCH_TO_H */
  33