xref: /linux/arch/s390/include/asm/barrier.h (revision d0b73b488c55df905ea8faaad079f8535629ed26)
1 /*
2  * Copyright IBM Corp. 1999, 2009
3  *
4  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
5  */
6 
7 #ifndef __ASM_BARRIER_H
8 #define __ASM_BARRIER_H
9 
10 /*
11  * Force strict CPU ordering.
12  * And yes, this is required on UP too when we're talking
13  * to devices.
14  */
15 
16 static inline void mb(void)
17 {
18 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
19 	/* Fast-BCR without checkpoint synchronization */
20 	asm volatile("bcr 14,0" : : : "memory");
21 #else
22 	asm volatile("bcr 15,0" : : : "memory");
23 #endif
24 }
25 
26 #define rmb()				mb()
27 #define wmb()				mb()
28 #define read_barrier_depends()		do { } while(0)
29 #define smp_mb()			mb()
30 #define smp_rmb()			rmb()
31 #define smp_wmb()			wmb()
32 #define smp_read_barrier_depends()	read_barrier_depends()
33 #define smp_mb__before_clear_bit()	smp_mb()
34 #define smp_mb__after_clear_bit()	smp_mb()
35 
36 #define set_mb(var, value)		do { var = value; mb(); } while (0)
37 
38 #endif /* __ASM_BARRIER_H */
39