xref: /openbmc/linux/arch/arm/include/asm/switch_to.h (revision 293d5b43)
1 #ifndef __ASM_ARM_SWITCH_TO_H
2 #define __ASM_ARM_SWITCH_TO_H
3 
4 #include <linux/thread_info.h>
5 
6 /*
7  * For v7 SMP cores running a preemptible kernel we may be pre-empted
8  * during a TLB maintenance operation, so execute an inner-shareable dsb
9  * to ensure that the maintenance completes in case we migrate to another
10  * CPU.
11  */
12 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
13 #define __complete_pending_tlbi()	dsb(ish)
14 #else
15 #define __complete_pending_tlbi()
16 #endif
17 
18 /*
19  * switch_to(prev, next) should switch from task `prev' to `next'
20  * `prev' will never be the same as `next'.  schedule() itself
21  * contains the memory barrier to tell GCC not to cache `current'.
22  */
23 extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
24 
25 #define switch_to(prev,next,last)					\
26 do {									\
27 	__complete_pending_tlbi();					\
28 	last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));	\
29 } while (0)
30 
31 #endif /* __ASM_ARM_SWITCH_TO_H */
32