tools/testing/selftests/rseq/rseq-x86.h

   1 /*
   2  * rseq-x86.h
   3  *
   4  * (C) Copyright 2016 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 #ifdef __x86_64__
  26
  27 #define smp_mb()        __asm__ __volatile__ ("mfence" : : : "memory")
  28 #define smp_rmb()       barrier()
  29 #define smp_wmb()       barrier()
  30
  31 #define smp_load_acquire(p)                                             \
  32 __extension__ ({                                                        \
  33         __typeof(*p) ____p1 = READ_ONCE(*p);                            \
  34         barrier();                                                      \
  35         ____p1;                                                         \
  36 })
  37
  38 #define smp_acquire__after_ctrl_dep()   smp_rmb()
  39
  40 #define smp_store_release(p, v)                                         \
  41 do {                                                                    \
  42         barrier();                                                      \
  43         WRITE_ONCE(*p, v);                                              \
  44 } while (0)
  45
  46 #define has_fast_acquire_release()      1
  47 #define has_single_copy_load_64()       1
  48
  49 /*
  50  * The __rseq_table section can be used by debuggers to better handle
  51  * single-stepping through the restartable critical sections.
  52  */
  53 #define RSEQ_FINISH_ASM(_target_final, _to_write_final, _start_value, \
  54                 _failure, _spec_store, _spec_input, \
  55                 _final_store, _final_input, _extra_clobber, \
  56                 _setup, _teardown, _scratch) \
  57 do { \
  58         _scratch \
  59         __asm__ __volatile__ goto ( \
  60                 ".pushsection __rseq_table, \"aw\"\n\t" \
  61                 ".balign 32\n\t" \
  62                 "3:\n\t" \
  63                 ".quad 1f, 2f, 4f, 0x0\n\t" \
  64                 ".popsection\n\t" \
  65                 "1:\n\t" \
  66                 _setup \
  67                 RSEQ_INJECT_ASM(1) \
  68                 "leaq 3b(%%rip), %%rax\n\t" \
  69                 "movq %%rax, %[rseq_cs]\n\t" \
  70                 RSEQ_INJECT_ASM(2) \
  71                 "cmpl %[start_event_counter], %[current_event_counter]\n\t" \
  72                 "jnz 4f\n\t" \
  73                 RSEQ_INJECT_ASM(3) \
  74                 _spec_store \
  75                 _final_store \
  76                 "2:\n\t" \
  77                 RSEQ_INJECT_ASM(5) \
  78                 _teardown \
  79                 ".pushsection __rseq_failure, \"a\"\n\t" \
  80                 "4:\n\t" \
  81                 _teardown \
  82                 "jmp %l[failure]\n\t" \
  83                 ".popsection\n\t" \
  84                 : /* gcc asm goto does not allow outputs */ \
  85                 : [start_event_counter]"r"((_start_value).event_counter), \
  86                   [current_event_counter]"m"((_start_value).rseqp->u.e.event_counter), \
  87                   [rseq_cs]"m"((_start_value).rseqp->rseq_cs) \
  88                   _spec_input \
  89                   _final_input \
  90                   RSEQ_INJECT_INPUT \
  91                 : "memory", "cc", "rax" \
  92                   _extra_clobber \
  93                   RSEQ_INJECT_CLOBBER \
  94                 : _failure \
  95         ); \
  96 } while (0)
  97
  98 #define RSEQ_FINISH_FINAL_STORE_ASM() \
  99                 "movq %[to_write_final], %[target_final]\n\t"
 100
 101 /* x86-64 is TSO */
 102 #define RSEQ_FINISH_FINAL_STORE_RELEASE_ASM() \
 103                 RSEQ_FINISH_FINAL_STORE_ASM()
 104
 105 #define RSEQ_FINISH_FINAL_STORE_INPUT(_target_final, _to_write_final) \
 106                 , [to_write_final]"r"(_to_write_final), \
 107                 [target_final]"m"(*(_target_final))
 108
 109 #define RSEQ_FINISH_SPECULATIVE_STORE_ASM() \
 110                 "movq %[to_write_spec], %[target_spec]\n\t" \
 111                 RSEQ_INJECT_ASM(4)
 112
 113 #define RSEQ_FINISH_SPECULATIVE_STORE_INPUT(_target_spec, _to_write_spec) \
 114                 , [to_write_spec]"r"(_to_write_spec), \
 115                 [target_spec]"m"(*(_target_spec))
 116
 117 /* TODO: implement a faster memcpy. */
 118 #define RSEQ_FINISH_MEMCPY_STORE_ASM() \
 119                 "test %[len_memcpy], %[len_memcpy]\n\t" \
 120                 "jz 333f\n\t" \
 121                 "222:\n\t" \
 122                 "movb (%[to_write_memcpy]), %%al\n\t" \
 123                 "movb %%al, (%[target_memcpy])\n\t" \
 124                 "inc %[to_write_memcpy]\n\t" \
 125                 "inc %[target_memcpy]\n\t" \
 126                 "dec %[len_memcpy]\n\t" \
 127                 "jnz 222b\n\t" \
 128                 "333:\n\t" \
 129                 RSEQ_INJECT_ASM(4)
 130
 131 #define RSEQ_FINISH_MEMCPY_STORE_INPUT(_target_memcpy, _to_write_memcpy, _len_memcpy) \
 132                 , [to_write_memcpy]"r"(_to_write_memcpy), \
 133                 [target_memcpy]"r"(_target_memcpy), \
 134                 [len_memcpy]"r"(_len_memcpy), \
 135                 [rseq_scratch0]"m"(rseq_scratch[0]), \
 136                 [rseq_scratch1]"m"(rseq_scratch[1]), \
 137                 [rseq_scratch2]"m"(rseq_scratch[2])
 138
 139 #define RSEQ_FINISH_MEMCPY_CLOBBER()    \
 140                 , "rax"
 141
 142 #define RSEQ_FINISH_MEMCPY_SCRATCH() \
 143                 uint64_t rseq_scratch[3];
 144
 145 /*
 146  * We need to save and restore those input registers so they can be
 147  * modified within the assembly.
 148  */
 149 #define RSEQ_FINISH_MEMCPY_SETUP() \
 150                 "movq %[to_write_memcpy], %[rseq_scratch0]\n\t" \
 151                 "movq %[target_memcpy], %[rseq_scratch1]\n\t" \
 152                 "movq %[len_memcpy], %[rseq_scratch2]\n\t"
 153
 154 #define RSEQ_FINISH_MEMCPY_TEARDOWN() \
 155                 "movq %[rseq_scratch2], %[len_memcpy]\n\t" \
 156                 "movq %[rseq_scratch1], %[target_memcpy]\n\t" \
 157                 "movq %[rseq_scratch0], %[to_write_memcpy]\n\t"
 158
 159 #elif __i386__
 160
 161 /*
 162  * Support older 32-bit architectures that do not implement fence
 163  * instructions.
 164  */
 165 #define smp_mb()        \
 166         __asm__ __volatile__ ("lock; addl $0,0(%%esp)" : : : "memory")
 167 #define smp_rmb()       \
 168         __asm__ __volatile__ ("lock; addl $0,0(%%esp)" : : : "memory")
 169 #define smp_wmb()       \
 170         __asm__ __volatile__ ("lock; addl $0,0(%%esp)" : : : "memory")
 171
 172 #define smp_load_acquire(p)                                             \
 173 __extension__ ({                                                        \
 174         __typeof(*p) ____p1 = READ_ONCE(*p);                            \
 175         smp_mb();                                                       \
 176         ____p1;                                                         \
 177 })
 178
 179 #define smp_acquire__after_ctrl_dep()   smp_rmb()
 180
 181 #define smp_store_release(p, v)                                         \
 182 do {                                                                    \
 183         smp_mb();                                                       \
 184         WRITE_ONCE(*p, v);                                              \
 185 } while (0)
 186
 187 #define has_fast_acquire_release()      0
 188 #define has_single_copy_load_64()       0
 189
 190 /*
 191  * Use eax as scratch register and take memory operands as input to
 192  * lessen register pressure. Especially needed when compiling
 193  * do_rseq_memcpy() in O0.
 194  */
 195 #define RSEQ_FINISH_ASM(_target_final, _to_write_final, _start_value, \
 196                 _failure, _spec_store, _spec_input, \
 197                 _final_store, _final_input, _extra_clobber, \
 198                 _setup, _teardown, _scratch) \
 199 do { \
 200         _scratch \
 201         __asm__ __volatile__ goto ( \
 202                 ".pushsection __rseq_table, \"aw\"\n\t" \
 203                 ".balign 32\n\t" \
 204                 "3:\n\t" \
 205                 ".long 1f, 0x0, 2f, 0x0, 4f, 0x0, 0x0, 0x0\n\t" \
 206                 ".popsection\n\t" \
 207                 "1:\n\t" \
 208                 _setup \
 209                 RSEQ_INJECT_ASM(1) \
 210                 "movl $3b, %[rseq_cs]\n\t" \
 211                 RSEQ_INJECT_ASM(2) \
 212                 "movl %[start_event_counter], %%eax\n\t" \
 213                 "cmpl %%eax, %[current_event_counter]\n\t" \
 214                 "jnz 4f\n\t" \
 215                 RSEQ_INJECT_ASM(3) \
 216                 _spec_store \
 217                 _final_store \
 218                 "2:\n\t" \
 219                 RSEQ_INJECT_ASM(5) \
 220                 _teardown \
 221                 ".pushsection __rseq_failure, \"a\"\n\t" \
 222                 "4:\n\t" \
 223                 _teardown \
 224                 "jmp %l[failure]\n\t" \
 225                 ".popsection\n\t" \
 226                 : /* gcc asm goto does not allow outputs */ \
 227                 : [start_event_counter]"m"((_start_value).event_counter), \
 228                   [current_event_counter]"m"((_start_value).rseqp->u.e.event_counter), \
 229                   [rseq_cs]"m"((_start_value).rseqp->rseq_cs) \
 230                   _spec_input \
 231                   _final_input \
 232                   RSEQ_INJECT_INPUT \
 233                 : "memory", "cc", "eax" \
 234                   _extra_clobber \
 235                   RSEQ_INJECT_CLOBBER \
 236                 : _failure \
 237         ); \
 238 } while (0)
 239
 240 #define RSEQ_FINISH_FINAL_STORE_ASM() \
 241                 "movl %[to_write_final], %%eax\n\t" \
 242                 "movl %%eax, %[target_final]\n\t"
 243
 244 #define RSEQ_FINISH_FINAL_STORE_RELEASE_ASM() \
 245                 "lock; addl $0,0(%%esp)\n\t" \
 246                 RSEQ_FINISH_FINAL_STORE_ASM()
 247
 248 #define RSEQ_FINISH_FINAL_STORE_INPUT(_target_final, _to_write_final) \
 249                 , [to_write_final]"m"(_to_write_final), \
 250                 [target_final]"m"(*(_target_final))
 251
 252 #define RSEQ_FINISH_SPECULATIVE_STORE_ASM() \
 253                 "movl %[to_write_spec], %%eax\n\t" \
 254                 "movl %%eax, %[target_spec]\n\t" \
 255                 RSEQ_INJECT_ASM(4)
 256
 257 #define RSEQ_FINISH_SPECULATIVE_STORE_INPUT(_target_spec, _to_write_spec) \
 258                 , [to_write_spec]"m"(_to_write_spec), \
 259                 [target_spec]"m"(*(_target_spec))
 260
 261 /* TODO: implement a faster memcpy. */
 262 #define RSEQ_FINISH_MEMCPY_STORE_ASM() \
 263                 "movl %[len_memcpy], %%eax\n\t" \
 264                 "test %%eax, %%eax\n\t" \
 265                 "jz 333f\n\t" \
 266                 "222:\n\t" \
 267                 "movb (%[to_write_memcpy]), %%al\n\t" \
 268                 "movb %%al, (%[target_memcpy])\n\t" \
 269                 "inc %[to_write_memcpy]\n\t" \
 270                 "inc %[target_memcpy]\n\t" \
 271                 "decl %[rseq_scratch2]\n\t" \
 272                 "jnz 222b\n\t" \
 273                 "333:\n\t" \
 274                 RSEQ_INJECT_ASM(4)
 275
 276 #define RSEQ_FINISH_MEMCPY_STORE_INPUT(_target_memcpy, _to_write_memcpy, _len_memcpy) \
 277                 , [to_write_memcpy]"r"(_to_write_memcpy), \
 278                 [target_memcpy]"r"(_target_memcpy), \
 279                 [len_memcpy]"m"(_len_memcpy), \
 280                 [rseq_scratch0]"m"(rseq_scratch[0]), \
 281                 [rseq_scratch1]"m"(rseq_scratch[1]), \
 282                 [rseq_scratch2]"m"(rseq_scratch[2])
 283
 284 #define RSEQ_FINISH_MEMCPY_CLOBBER()
 285
 286 #define RSEQ_FINISH_MEMCPY_SCRATCH() \
 287                 uint32_t rseq_scratch[3];
 288
 289 /*
 290  * We need to save and restore those input registers so they can be
 291  * modified within the assembly.
 292  */
 293 #define RSEQ_FINISH_MEMCPY_SETUP() \
 294                 "movl %[to_write_memcpy], %[rseq_scratch0]\n\t" \
 295                 "movl %[target_memcpy], %[rseq_scratch1]\n\t" \
 296                 "movl %[len_memcpy], %%eax\n\t" \
 297                 "movl %%eax, %[rseq_scratch2]\n\t"
 298
 299 #define RSEQ_FINISH_MEMCPY_TEARDOWN() \
 300                 "movl %[rseq_scratch1], %[target_memcpy]\n\t" \
 301                 "movl %[rseq_scratch0], %[to_write_memcpy]\n\t"
 302
 303 #endif