x86_64: prepare shared kernel/head.S
[linux-2.6] / arch / x86_64 / lib / thunk.S
1 /*
2  * Save registers before calling assembly functions. This avoids
3  * disturbance of register allocation in some inline assembly constructs.
4  * Copyright 2001,2002 by Andi Kleen, SuSE Labs.
5  * Subject to the GNU public license, v.2. No warranty of any kind.
6  */
7
8         #include <linux/linkage.h>
9         #include <asm/dwarf2.h>
10         #include <asm/calling.h>                        
11         #include <asm/rwlock.h>
12                 
13         /* rdi: arg1 ... normal C conventions. rax is saved/restored. */        
14         .macro thunk name,func
15         .globl \name
16 \name:  
17         CFI_STARTPROC
18         SAVE_ARGS
19         call \func
20         jmp  restore
21         CFI_ENDPROC
22         .endm
23
24         /* rdi: arg1 ... normal C conventions. rax is passed from C. */         
25         .macro thunk_retrax name,func
26         .globl \name
27 \name:  
28         CFI_STARTPROC
29         SAVE_ARGS
30         call \func
31         jmp  restore_norax
32         CFI_ENDPROC
33         .endm
34         
35
36         .section .sched.text
37 #ifdef CONFIG_RWSEM_XCHGADD_ALGORITHM
38         thunk rwsem_down_read_failed_thunk,rwsem_down_read_failed
39         thunk rwsem_down_write_failed_thunk,rwsem_down_write_failed
40         thunk rwsem_wake_thunk,rwsem_wake
41         thunk rwsem_downgrade_thunk,rwsem_downgrade_wake
42 #endif  
43         
44         thunk __down_failed,__down
45         thunk_retrax __down_failed_interruptible,__down_interruptible
46         thunk_retrax __down_failed_trylock,__down_trylock
47         thunk __up_wakeup,__up
48
49 #ifdef CONFIG_TRACE_IRQFLAGS
50         thunk trace_hardirqs_on_thunk,trace_hardirqs_on
51         thunk trace_hardirqs_off_thunk,trace_hardirqs_off
52 #endif
53         
54         /* SAVE_ARGS below is used only for the .cfi directives it contains. */
55         CFI_STARTPROC
56         SAVE_ARGS
57 restore:
58         RESTORE_ARGS
59         ret     
60         CFI_ENDPROC
61         
62         CFI_STARTPROC
63         SAVE_ARGS
64 restore_norax:  
65         RESTORE_ARGS 1
66         ret
67         CFI_ENDPROC