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switch_to.h
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1 /*
2  * Copyright 2004-2009 Analog Devices Inc.
3  * Tony Kou ([email protected])
4  *
5  * Licensed under the GPL-2 or later
6  */
7 
8 #ifndef _BLACKFIN_SWITCH_TO_H
9 #define _BLACKFIN_SWITCH_TO_H
10 
11 #define prepare_to_switch() do { } while(0)
12 
13 /*
14  * switch_to(n) should switch tasks to task ptr, first checking that
15  * ptr isn't the current task, in which case it does nothing.
16  */
17 
18 #include <asm/l1layout.h>
19 #include <asm/mem_map.h>
20 
21 asmlinkage struct task_struct *resume(struct task_struct *prev, struct task_struct *next);
22 
23 #ifndef CONFIG_SMP
24 #define switch_to(prev,next,last) \
25 do { \
26  memcpy (&task_thread_info(prev)->l1_task_info, L1_SCRATCH_TASK_INFO, \
27  sizeof *L1_SCRATCH_TASK_INFO); \
28  memcpy (L1_SCRATCH_TASK_INFO, &task_thread_info(next)->l1_task_info, \
29  sizeof *L1_SCRATCH_TASK_INFO); \
30  (last) = resume (prev, next); \
31 } while (0)
32 #else
33 #define switch_to(prev, next, last) \
34 do { \
35  (last) = resume(prev, next); \
36 } while (0)
37 #endif
38 
39 #endif /* _BLACKFIN_SWITCH_TO_H */