linux/arch/avr32/include/asm/switch_to.h

50 lines
1.4 KiB
C

/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_AVR32_SWITCH_TO_H
#define __ASM_AVR32_SWITCH_TO_H
/*
* Help PathFinder and other Nexus-compliant debuggers keep track of
* the current PID by emitting an Ownership Trace Message each time we
* switch task.
*/
#ifdef CONFIG_OWNERSHIP_TRACE
#include <asm/ocd.h>
#define ocd_switch(prev, next) \
do { \
ocd_write(PID, prev->pid); \
ocd_write(PID, next->pid); \
} while(0)
#else
#define ocd_switch(prev, next)
#endif
/*
* switch_to(prev, next, last) should switch from task `prev' to task
* `next'. `prev' will never be the same as `next'.
*
* We just delegate everything to the __switch_to assembly function,
* which is implemented in arch/avr32/kernel/switch_to.S
*
* mb() tells GCC not to cache `current' across this call.
*/
struct cpu_context;
struct task_struct;
extern struct task_struct *__switch_to(struct task_struct *,
struct cpu_context *,
struct cpu_context *);
#define switch_to(prev, next, last) \
do { \
ocd_switch(prev, next); \
last = __switch_to(prev, &prev->thread.cpu_context + 1, \
&next->thread.cpu_context); \
} while (0)
#endif /* __ASM_AVR32_SWITCH_TO_H */