1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_ARM_SWITCH_TO_H
3 #define __ASM_ARM_SWITCH_TO_H
5 #include <linux/thread_info.h>
6 #include <asm/smp_plat.h>
9 * For v7 SMP cores running a preemptible kernel we may be pre-empted
10 * during a TLB maintenance operation, so execute an inner-shareable dsb
11 * to ensure that the maintenance completes in case we migrate to another
14 #if defined(CONFIG_PREEMPTION) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
15 #define __complete_pending_tlbi() dsb(ish)
17 #define __complete_pending_tlbi()
21 * switch_to(prev, next) should switch from task `prev' to `next'
22 * `prev' will never be the same as `next'. schedule() itself
23 * contains the memory barrier to tell GCC not to cache `current'.
25 extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
27 #define switch_to(prev,next,last) \
29 __complete_pending_tlbi(); \
30 if (IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || is_smp()) \
31 __this_cpu_write(__entry_task, next); \
32 last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \
35 #endif /* __ASM_ARM_SWITCH_TO_H */