1 #ifndef __ASM_SH64_SMPLOCK_H
2 #define __ASM_SH64_SMPLOCK_H
3 
4 /*
5  * This file is subject to the terms and conditions of the GNU General Public
6  * License.  See the file "COPYING" in the main directory of this archive
7  * for more details.
8  *
9  * include/asm-sh64/smplock.h
10  *
11  * Copyright (C) 2000, 2001  Paolo Alberelli
12  *
13  */
14 
15 #include <linux/config.h>
16 
17 #ifndef CONFIG_SMP
18 
19 #define lock_kernel()				do { } while(0)
20 #define unlock_kernel()				do { } while(0)
21 #define release_kernel_lock(task, cpu, depth)	((depth) = 1)
22 #define reacquire_kernel_lock(task, cpu, depth)	do { } while(0)
23 
24 #else
25 
26 #error "We do not support SMP on ST50 yet"
27 /*
28  * Default SMP lock implementation
29  */
30 
31 #include <linux/interrupt.h>
32 #include <asm/spinlock.h>
33 
34 extern spinlock_t kernel_flag;
35 
36 /*
37  * Getting the big kernel lock.
38  *
39  * This cannot happen asynchronously,
40  * so we only need to worry about other
41  * CPU's.
42  */
lock_kernel(void)43 extern __inline__ void lock_kernel(void)
44 {
45 	if (!++current->lock_depth)
46 		spin_lock(&kernel_flag);
47 }
48 
unlock_kernel(void)49 extern __inline__ void unlock_kernel(void)
50 {
51 	if (--current->lock_depth < 0)
52 		spin_unlock(&kernel_flag);
53 }
54 
55 /*
56  * Release global kernel lock and global interrupt lock
57  */
58 #define release_kernel_lock(task, cpu) \
59 do { \
60 	if (task->lock_depth >= 0) \
61 		spin_unlock(&kernel_flag); \
62 	release_irqlock(cpu); \
63 	__sti(); \
64 } while (0)
65 
66 /*
67  * Re-acquire the kernel lock
68  */
69 #define reacquire_kernel_lock(task) \
70 do { \
71 	if (task->lock_depth >= 0) \
72 		spin_lock(&kernel_flag); \
73 } while (0)
74 
75 #endif /* CONFIG_SMP */
76 
77 #endif /* __ASM_SH64_SMPLOCK_H */
78