projects / urcu.git / blame
| Commit | Line | Data |
|---|---|---|
| ac26f1a8 JB |
1 | #ifndef _ARCH_ATOMIC_S390_H |
| 2 | #define _ARCH_ATOMIC_S390_H | |
| 3 | ||
| 4 | /* | |
| 5 | * Atomic exchange operations for the S390 architecture. | |
| 6 | * | |
| 7 | * Copyright (C) 2009 Novell, Inc. | |
| 8 | * Author: Jan Blunck <jblunck@suse.de> | |
| 9 | * | |
| 10 | * This is taken from the Principles of Operation Appendix A "Conditional | |
| 11 | * Swapping Instructions (CS, CDS)". | |
| 12 | * | |
| 13 | * This program is free software; you can redistribute it and/or modify it | |
| 14 | * under the terms of the GNU Lesser General Public License version 2.1 as | |
| 15 | * published by the Free Software Foundation. | |
| 16 | */ | |
| 17 | ||
| 18 | #ifndef __SIZEOF_LONG__ | |
| 19 | #ifdef __s390x__ | |
| 20 | #define __SIZEOF_LONG__ 8 | |
| 21 | #else | |
| 22 | #define __SIZEOF_LONG__ 4 | |
| 23 | #endif | |
| 24 | #endif | |
| 25 | ||
| 26 | #ifndef BITS_PER_LONG | |
| 27 | #define BITS_PER_LONG (__SIZEOF_LONG__ * 8) | |
| 28 | #endif | |
| 29 | ||
| 30 | #ifndef _INCLUDE_API_H | |
| 31 | ||
| a9a05d42 | 32 | static inline __attribute__((always_inline)) |
| ac26f1a8 JB |
33 | unsigned int atomic_exchange_32(volatile unsigned int *addr, unsigned int val) |
| 34 | { | |
| 35 | unsigned int result; | |
| 36 | ||
| 37 | __asm__ __volatile__( | |
| 38 | "0: cs %0,%2,%1\n" | |
| 39 | " brc 4,0b\n" | |
| 40 | : "=&r"(result), "=m" (*addr) | |
| 41 | : "r"(val), "m" (*addr) | |
| 42 | : "memory", "cc"); | |
| 43 | ||
| 44 | return result; | |
| 45 | } | |
| 46 | ||
| 47 | #if (BITS_PER_LONG == 64) | |
| 48 | ||
| a9a05d42 | 49 | static inline __attribute__((always_inline)) |
| ac26f1a8 JB |
50 | unsigned long atomic_exchange_64(volatile unsigned long *addr, |
| 51 | unsigned long val) | |
| 52 | { | |
| 53 | unsigned long result; | |
| 54 | ||
| 55 | __asm__ __volatile__( | |
| 56 | "0: csg %0,%2,%1\n" | |
| 57 | " brc 4,0b\n" | |
| 58 | : "=&r"(result), "=m" (*addr) | |
| 59 | : "r"(val), "m" (*addr) | |
| 60 | : "memory", "cc"); | |
| 61 | ||
| 62 | return result; | |
| 63 | } | |
| 64 | ||
| 65 | #endif | |
| 66 | ||
| a9a05d42 | 67 | static inline __attribute__((always_inline)) |
| ac26f1a8 JB |
68 | unsigned long _atomic_exchange(volatile void *addr, unsigned long val, int len) |
| 69 | { | |
| 70 | switch (len) { | |
| 71 | case 4: | |
| 72 | return atomic_exchange_32(addr, val); | |
| 73 | #if (BITS_PER_LONG == 64) | |
| 74 | case 8: | |
| 75 | return atomic_exchange_64(addr, val); | |
| 76 | #endif | |
| 77 | default: | |
| 78 | __asm__ __volatile__(".long 0xd00d00"); | |
| 79 | } | |
| 80 | ||
| 81 | return 0; | |
| 82 | } | |
| 83 | ||
| a9a05d42 JB |
84 | #define xchg(addr, v) \ |
| 85 | (__typeof__(*(addr))) _atomic_exchange((addr), (unsigned long)(v), \ | |
| 86 | sizeof(*(addr))) | |
| ac26f1a8 JB |
87 | |
| 88 | #endif /* #ifndef _INCLUDE_API_H */ | |
| 89 | ||
| 90 | #endif /* ARCH_ATOMIC_S390_H */ |