kernel/arch/arm/include/asm/switch_to.h

   1 #ifndef __ASM_ARM_SWITCH_TO_H
   2 #define __ASM_ARM_SWITCH_TO_H
   3
   4 #include <linux/thread_info.h>
   5
   6 #if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM
   7 void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p);
   8 #else
   9 static inline void
  10 switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { }
  11 #endif
  12
  13 /*
  14  * For v7 SMP cores running a preemptible kernel we may be pre-empted
  15  * during a TLB maintenance operation, so execute an inner-shareable dsb
  16  * to ensure that the maintenance completes in case we migrate to another
  17  * CPU.
  18  */
  19 #if defined(CONFIG_PREEMPT) && defined(CONFIG_SMP) && defined(CONFIG_CPU_V7)
  20 #define __complete_pending_tlbi()       dsb(ish)
  21 #else
  22 #define __complete_pending_tlbi()
  23 #endif
  24
  25 /*
  26  * switch_to(prev, next) should switch from task `prev' to `next'
  27  * `prev' will never be the same as `next'.  schedule() itself
  28  * contains the memory barrier to tell GCC not to cache `current'.
  29  */
  30 extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
  31
  32 #define switch_to(prev,next,last)                                       \
  33 do {                                                                    \
  34         __complete_pending_tlbi();                                      \
  35         switch_kmaps(prev, next);                                       \
  36         last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));        \
  37 } while (0)
  38
  39 #endif /* __ASM_ARM_SWITCH_TO_H */