arch/frv/include/asm/switch_to.h

   1 /* FR-V CPU basic task switching
   2  *
   3  * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12 #ifndef _ASM_SWITCH_TO_H
  13 #define _ASM_SWITCH_TO_H
  14
  15 #include <linux/thread_info.h>
  16
  17 /*
  18  * switch_to(prev, next) should switch from task `prev' to `next'
  19  * `prev' will never be the same as `next'.
  20  * The `mb' is to tell GCC not to cache `current' across this call.
  21  */
  22 extern asmlinkage
  23 struct task_struct *__switch_to(struct thread_struct *prev_thread,
  24                                 struct thread_struct *next_thread,
  25                                 struct task_struct *prev);
  26
  27 #define switch_to(prev, next, last)                                     \
  28 do {                                                                    \
  29         (prev)->thread.sched_lr =                                       \
  30                 (unsigned long) __builtin_return_address(0);            \
  31         (last) = __switch_to(&(prev)->thread, &(next)->thread, (prev)); \
  32         mb();                                                           \
  33 } while(0)
  34
  35 #endif /* _ASM_SWITCH_TO_H */