urcu/uatomic_arch_s390.h

   1 #ifndef _URCU_UATOMIC_ARCH_S390_H
   2 #define _URCU_UATOMIC_ARCH_S390_H
   3
   4 /*
   5  * Atomic exchange operations for the S390 architecture. Based on information
   6  * taken from the Principles of Operation Appendix A "Conditional Swapping
   7  * Instructions (CS, CDS)".
   8  *
   9  * Copyright (c) 2009 Novell, Inc.
  10  * Author: Jan Blunck <jblunck@suse.de>
  11  * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
  12  *
  13  * Permission is hereby granted, free of charge, to any person obtaining a copy
  14  * of this software and associated documentation files (the "Software"), to
  15  * deal in the Software without restriction, including without limitation the
  16  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  17  * sell copies of the Software, and to permit persons to whom the Software is
  18  * furnished to do so, subject to the following conditions:
  19  *
  20  * The above copyright notice and this permission notice shall be included in
  21  * all copies or substantial portions of the Software.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  24  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  25  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  26  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  27  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  28  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  29  * IN THE SOFTWARE.
  30  */
  31
  32 #include <urcu/compiler.h>
  33 #include <urcu/system.h>
  34
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 #ifndef __SIZEOF_LONG__
  40 #ifdef __s390x__
  41 #define __SIZEOF_LONG__ 8
  42 #else
  43 #define __SIZEOF_LONG__ 4
  44 #endif
  45 #endif
  46
  47 #ifndef BITS_PER_LONG
  48 #define BITS_PER_LONG   (__SIZEOF_LONG__ * 8)
  49 #endif
  50
  51 #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
  52 #define COMPILER_HAVE_SHORT_MEM_OPERAND
  53 #endif
  54
  55 /*
  56  * MEMOP assembler operand rules:
  57  * - op refer to MEMOP_IN operand
  58  * - MEMOP_IN can expand to more than a single operand. Use it at the end of
  59  *   operand list only.
  60  */
  61
  62 #ifdef COMPILER_HAVE_SHORT_MEM_OPERAND
  63
  64 #define MEMOP_OUT(addr) "=Q" (*(addr))
  65 #define MEMOP_IN        "Q" (*(addr))
  66 #define MEMOP_REF(op)   #op             /* op refer to MEMOP_IN operand */
  67
  68 #else /* !COMPILER_HAVE_SHORT_MEM_OPERAND */
  69
  70 #define MEMOP_OUT(addr) "=m" (*(addr))
  71 #define MEMOP_IN        "a" (addr), "m" (*(addr))
  72 #define MEMOP_REF(op)   "0(" #op ")"    /* op refer to MEMOP_IN operand */
  73
  74 #endif /* !COMPILER_HAVE_SHORT_MEM_OPERAND */
  75
  76 struct __uatomic_dummy {
  77         unsigned long v[10];
  78 };
  79 #define __hp(x) ((struct __uatomic_dummy *)(x))
  80
  81 #define uatomic_set(addr, v)    STORE_SHARED(*(addr), (v))
  82 #define uatomic_read(addr)      LOAD_SHARED(*(addr))
  83
  84 /* xchg */
  85
  86 static inline __attribute__((always_inline))
  87 unsigned long _uatomic_exchange(volatile void *addr, unsigned long val, int len)
  88 {
  89         switch (len) {
  90         case 4:
  91         {
  92                 unsigned int old_val;
  93
  94                 __asm__ __volatile__(
  95                         "0:     cs %0,%2," MEMOP_REF(%3) "\n"
  96                         "       brc 4,0b\n"
  97                         : "=&r" (old_val), MEMOP_OUT (__hp(addr))
  98                         : "r" (val), MEMOP_IN (__hp(addr))
  99                         : "memory", "cc");
 100                 return old_val;
 101         }
 102 #if (BITS_PER_LONG == 64)
 103         case 8:
 104         {
 105                 unsigned long old_val;
 106
 107                 __asm__ __volatile__(
 108                         "0:     csg %0,%2," MEMOP_REF(%3) "\n"
 109                         "       brc 4,0b\n"
 110                         : "=&r" (old_val), MEMOP_OUT (__hp(addr))
 111                         : "r" (val), MEMOP_IN (__hp(addr))
 112                         : "memory", "cc");
 113                 return old_val;
 114         }
 115 #endif
 116         default:
 117                 __asm__ __volatile__(".long     0xd00d00");
 118         }
 119
 120         return 0;
 121 }
 122
 123 #define uatomic_xchg(addr, v)                                               \
 124         (__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \
 125                                                sizeof(*(addr)))
 126
 127 /* cmpxchg */
 128
 129 static inline __attribute__((always_inline))
 130 unsigned long _uatomic_cmpxchg(void *addr, unsigned long old,
 131                                unsigned long _new, int len)
 132 {
 133         switch (len) {
 134         case 4:
 135         {
 136                 unsigned int old_val = (unsigned int)old;
 137
 138                 __asm__ __volatile__(
 139                         "       cs %0,%2," MEMOP_REF(%3) "\n"
 140                         : "+r" (old_val), MEMOP_OUT (__hp(addr))
 141                         : "r" (_new), MEMOP_IN (__hp(addr))
 142                         : "memory", "cc");
 143                 return old_val;
 144         }
 145 #if (BITS_PER_LONG == 64)
 146         case 8:
 147         {
 148                 __asm__ __volatile__(
 149                         "       csg %0,%2," MEMOP_REF(%3) "\n"
 150                         : "+r" (old), MEMOP_OUT (__hp(addr))
 151                         : "r" (_new), MEMOP_IN (__hp(addr))
 152                         : "memory", "cc");
 153                 return old;
 154         }
 155 #endif
 156         default:
 157                 __asm__ __volatile__(".long     0xd00d00");
 158         }
 159
 160         return 0;
 161 }
 162
 163 #define uatomic_cmpxchg(addr, old, _new)                                \
 164         (__typeof__(*(addr))) _uatomic_cmpxchg((addr),                  \
 165                                                (unsigned long)(old),    \
 166                                                (unsigned long)(_new),   \
 167                                                sizeof(*(addr)))
 168
 169 /* uatomic_add_return */
 170
 171 static inline __attribute__((always_inline))
 172 unsigned long _uatomic_add_return(void *addr, unsigned long val, int len)
 173 {
 174         switch (len) {
 175         case 4:
 176         {
 177                 unsigned int old, oldt;
 178
 179                 oldt = uatomic_read((unsigned int *)addr);
 180                 do {
 181                         old = oldt;
 182                         oldt = _uatomic_cmpxchg(addr, old, old + val, 4);
 183                 } while (oldt != old);
 184
 185                 return old + val;
 186         }
 187 #if (BITS_PER_LONG == 64)
 188         case 8:
 189         {
 190                 unsigned long old, oldt;
 191
 192                 oldt = uatomic_read((unsigned long *)addr);
 193                 do {
 194                         old = oldt;
 195                         oldt = _uatomic_cmpxchg(addr, old, old + val, 8);
 196                 } while (oldt != old);
 197
 198                 return old + val;
 199         }
 200 #endif
 201         }
 202         __builtin_trap();
 203         return 0;
 204 }
 205
 206 #define uatomic_add_return(addr, v)                                     \
 207         ((__typeof__(*(addr))) _uatomic_add_return((addr),              \
 208                                                   (unsigned long)(v),   \
 209                                                   sizeof(*(addr))))
 210
 211 /* uatomic_sub_return, uatomic_add, uatomic_sub, uatomic_inc, uatomic_dec */
 212
 213 #define uatomic_sub_return(addr, v)     uatomic_add_return((addr), -(v))
 214
 215 #define uatomic_add(addr, v)            (void)uatomic_add_return((addr), (v))
 216 #define uatomic_sub(addr, v)            (void)uatomic_sub_return((addr), (v))
 217
 218 #define uatomic_inc(addr)               uatomic_add((addr), 1)
 219 #define uatomic_dec(addr)               uatomic_add((addr), -1)
 220
 221 #define compat_uatomic_cmpxchg(ptr, old, _new)  uatomic_cmpxchg(ptr, old, _new)
 222
 223 #ifdef __cplusplus
 224 }
 225 #endif
 226
 227 #endif /* _URCU_UATOMIC_ARCH_S390_H */