atomic_linux_ppc.hpp revision 13477:4d61110c6046
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See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26#ifndef OS_CPU_LINUX_PPC_VM_ATOMIC_LINUX_PPC_HPP 27#define OS_CPU_LINUX_PPC_VM_ATOMIC_LINUX_PPC_HPP 28 29#ifndef PPC64 30#error "Atomic currently only implemented for PPC64" 31#endif 32 33// Implementation of class atomic 34 35inline void Atomic::store (jbyte store_value, jbyte* dest) { *dest = store_value; } 36inline void Atomic::store (jshort store_value, jshort* dest) { *dest = store_value; } 37inline void Atomic::store (jint store_value, jint* dest) { *dest = store_value; } 38inline void Atomic::store (jlong store_value, jlong* dest) { *dest = store_value; } 39inline void Atomic::store_ptr(intptr_t store_value, intptr_t* dest) { *dest = store_value; } 40inline void Atomic::store_ptr(void* store_value, void* dest) { *(void**)dest = store_value; } 41 42inline void Atomic::store (jbyte store_value, volatile jbyte* dest) { *dest = store_value; } 43inline void Atomic::store (jshort store_value, volatile jshort* dest) { *dest = store_value; } 44inline void Atomic::store (jint store_value, volatile jint* dest) { *dest = store_value; } 45inline void Atomic::store (jlong store_value, volatile jlong* dest) { *dest = store_value; } 46inline void Atomic::store_ptr(intptr_t store_value, volatile intptr_t* dest) { *dest = store_value; } 47inline void Atomic::store_ptr(void* store_value, volatile void* dest) { *(void* volatile *)dest = store_value; } 48 49inline jlong Atomic::load(const volatile jlong* src) { return *src; } 50 51// 52// machine barrier instructions: 53// 54// - sync two-way memory barrier, aka fence 55// - lwsync orders Store|Store, 56// Load|Store, 57// Load|Load, 58// but not Store|Load 59// - eieio orders memory accesses for device memory (only) 60// - isync invalidates speculatively executed instructions 61// From the POWER ISA 2.06 documentation: 62// "[...] an isync instruction prevents the execution of 63// instructions following the isync until instructions 64// preceding the isync have completed, [...]" 65// From IBM's AIX assembler reference: 66// "The isync [...] instructions causes the processor to 67// refetch any instructions that might have been fetched 68// prior to the isync instruction. The instruction isync 69// causes the processor to wait for all previous instructions 70// to complete. Then any instructions already fetched are 71// discarded and instruction processing continues in the 72// environment established by the previous instructions." 73// 74// semantic barrier instructions: 75// (as defined in orderAccess.hpp) 76// 77// - release orders Store|Store, (maps to lwsync) 78// Load|Store 79// - acquire orders Load|Store, (maps to lwsync) 80// Load|Load 81// - fence orders Store|Store, (maps to sync) 82// Load|Store, 83// Load|Load, 84// Store|Load 85// 86 87#define strasm_sync "\n sync \n" 88#define strasm_lwsync "\n lwsync \n" 89#define strasm_isync "\n isync \n" 90#define strasm_release strasm_lwsync 91#define strasm_acquire strasm_lwsync 92#define strasm_fence strasm_sync 93#define strasm_nobarrier "" 94#define strasm_nobarrier_clobber_memory "" 95 96inline jint Atomic::add (jint add_value, volatile jint* dest) { 97 98 unsigned int result; 99 100 __asm__ __volatile__ ( 101 strasm_lwsync 102 "1: lwarx %0, 0, %2 \n" 103 " add %0, %0, %1 \n" 104 " stwcx. %0, 0, %2 \n" 105 " bne- 1b \n" 106 strasm_isync 107 : /*%0*/"=&r" (result) 108 : /*%1*/"r" (add_value), /*%2*/"r" (dest) 109 : "cc", "memory" ); 110 111 return (jint) result; 112} 113 114 115inline intptr_t Atomic::add_ptr(intptr_t add_value, volatile intptr_t* dest) { 116 117 long result; 118 119 __asm__ __volatile__ ( 120 strasm_lwsync 121 "1: ldarx %0, 0, %2 \n" 122 " add %0, %0, %1 \n" 123 " stdcx. %0, 0, %2 \n" 124 " bne- 1b \n" 125 strasm_isync 126 : /*%0*/"=&r" (result) 127 : /*%1*/"r" (add_value), /*%2*/"r" (dest) 128 : "cc", "memory" ); 129 130 return (intptr_t) result; 131} 132 133inline void* Atomic::add_ptr(intptr_t add_value, volatile void* dest) { 134 return (void*)add_ptr(add_value, (volatile intptr_t*)dest); 135} 136 137 138inline void Atomic::inc (volatile jint* dest) { 139 140 unsigned int temp; 141 142 __asm__ __volatile__ ( 143 strasm_nobarrier 144 "1: lwarx %0, 0, %2 \n" 145 " addic %0, %0, 1 \n" 146 " stwcx. %0, 0, %2 \n" 147 " bne- 1b \n" 148 strasm_nobarrier 149 : /*%0*/"=&r" (temp), "=m" (*dest) 150 : /*%2*/"r" (dest), "m" (*dest) 151 : "cc" strasm_nobarrier_clobber_memory); 152 153} 154 155inline void Atomic::inc_ptr(volatile intptr_t* dest) { 156 157 long temp; 158 159 __asm__ __volatile__ ( 160 strasm_nobarrier 161 "1: ldarx %0, 0, %2 \n" 162 " addic %0, %0, 1 \n" 163 " stdcx. %0, 0, %2 \n" 164 " bne- 1b \n" 165 strasm_nobarrier 166 : /*%0*/"=&r" (temp), "=m" (*dest) 167 : /*%2*/"r" (dest), "m" (*dest) 168 : "cc" strasm_nobarrier_clobber_memory); 169 170} 171 172inline void Atomic::inc_ptr(volatile void* dest) { 173 inc_ptr((volatile intptr_t*)dest); 174} 175 176 177inline void Atomic::dec (volatile jint* dest) { 178 179 unsigned int temp; 180 181 __asm__ __volatile__ ( 182 strasm_nobarrier 183 "1: lwarx %0, 0, %2 \n" 184 " addic %0, %0, -1 \n" 185 " stwcx. %0, 0, %2 \n" 186 " bne- 1b \n" 187 strasm_nobarrier 188 : /*%0*/"=&r" (temp), "=m" (*dest) 189 : /*%2*/"r" (dest), "m" (*dest) 190 : "cc" strasm_nobarrier_clobber_memory); 191 192} 193 194inline void Atomic::dec_ptr(volatile intptr_t* dest) { 195 196 long temp; 197 198 __asm__ __volatile__ ( 199 strasm_nobarrier 200 "1: ldarx %0, 0, %2 \n" 201 " addic %0, %0, -1 \n" 202 " stdcx. %0, 0, %2 \n" 203 " bne- 1b \n" 204 strasm_nobarrier 205 : /*%0*/"=&r" (temp), "=m" (*dest) 206 : /*%2*/"r" (dest), "m" (*dest) 207 : "cc" strasm_nobarrier_clobber_memory); 208 209} 210 211inline void Atomic::dec_ptr(volatile void* dest) { 212 dec_ptr((volatile intptr_t*)dest); 213} 214 215inline jint Atomic::xchg(jint exchange_value, volatile jint* dest) { 216 217 // Note that xchg_ptr doesn't necessarily do an acquire 218 // (see synchronizer.cpp). 219 220 unsigned int old_value; 221 const uint64_t zero = 0; 222 223 __asm__ __volatile__ ( 224 /* lwsync */ 225 strasm_lwsync 226 /* atomic loop */ 227 "1: \n" 228 " lwarx %[old_value], %[dest], %[zero] \n" 229 " stwcx. %[exchange_value], %[dest], %[zero] \n" 230 " bne- 1b \n" 231 /* isync */ 232 strasm_sync 233 /* exit */ 234 "2: \n" 235 /* out */ 236 : [old_value] "=&r" (old_value), 237 "=m" (*dest) 238 /* in */ 239 : [dest] "b" (dest), 240 [zero] "r" (zero), 241 [exchange_value] "r" (exchange_value), 242 "m" (*dest) 243 /* clobber */ 244 : "cc", 245 "memory" 246 ); 247 248 return (jint) old_value; 249} 250 251inline intptr_t Atomic::xchg_ptr(intptr_t exchange_value, volatile intptr_t* dest) { 252 253 // Note that xchg_ptr doesn't necessarily do an acquire 254 // (see synchronizer.cpp). 255 256 long old_value; 257 const uint64_t zero = 0; 258 259 __asm__ __volatile__ ( 260 /* lwsync */ 261 strasm_lwsync 262 /* atomic loop */ 263 "1: \n" 264 " ldarx %[old_value], %[dest], %[zero] \n" 265 " stdcx. %[exchange_value], %[dest], %[zero] \n" 266 " bne- 1b \n" 267 /* isync */ 268 strasm_sync 269 /* exit */ 270 "2: \n" 271 /* out */ 272 : [old_value] "=&r" (old_value), 273 "=m" (*dest) 274 /* in */ 275 : [dest] "b" (dest), 276 [zero] "r" (zero), 277 [exchange_value] "r" (exchange_value), 278 "m" (*dest) 279 /* clobber */ 280 : "cc", 281 "memory" 282 ); 283 284 return (intptr_t) old_value; 285} 286 287inline void* Atomic::xchg_ptr(void* exchange_value, volatile void* dest) { 288 return (void*)xchg_ptr((intptr_t)exchange_value, (volatile intptr_t*)dest); 289} 290 291inline void cmpxchg_pre_membar(cmpxchg_memory_order order) { 292 if (order != memory_order_relaxed) { 293 __asm__ __volatile__ ( 294 /* fence */ 295 strasm_sync 296 ); 297 } 298} 299 300inline void cmpxchg_post_membar(cmpxchg_memory_order order) { 301 if (order != memory_order_relaxed) { 302 __asm__ __volatile__ ( 303 /* fence */ 304 strasm_sync 305 ); 306 } 307} 308 309template<> 310template<typename T> 311inline T Atomic::PlatformCmpxchg<1>::operator()(T exchange_value, 312 T volatile* dest, 313 T compare_value, 314 cmpxchg_memory_order order) const { 315 STATIC_ASSERT(1 == sizeof(T)); 316 317 // Note that cmpxchg guarantees a two-way memory barrier across 318 // the cmpxchg, so it's really a a 'fence_cmpxchg_fence' if not 319 // specified otherwise (see atomic.hpp). 320 321 // Using 32 bit internally. 322 volatile int *dest_base = (volatile int*)((uintptr_t)dest & ~3); 323 324#ifdef VM_LITTLE_ENDIAN 325 const unsigned int shift_amount = ((uintptr_t)dest & 3) * 8; 326#else 327 const unsigned int shift_amount = ((~(uintptr_t)dest) & 3) * 8; 328#endif 329 const unsigned int masked_compare_val = ((unsigned int)(unsigned char)compare_value), 330 masked_exchange_val = ((unsigned int)(unsigned char)exchange_value), 331 xor_value = (masked_compare_val ^ masked_exchange_val) << shift_amount; 332 333 unsigned int old_value, value32; 334 335 cmpxchg_pre_membar(order); 336 337 __asm__ __volatile__ ( 338 /* simple guard */ 339 " lbz %[old_value], 0(%[dest]) \n" 340 " cmpw %[masked_compare_val], %[old_value] \n" 341 " bne- 2f \n" 342 /* atomic loop */ 343 "1: \n" 344 " lwarx %[value32], 0, %[dest_base] \n" 345 /* extract byte and compare */ 346 " srd %[old_value], %[value32], %[shift_amount] \n" 347 " clrldi %[old_value], %[old_value], 56 \n" 348 " cmpw %[masked_compare_val], %[old_value] \n" 349 " bne- 2f \n" 350 /* replace byte and try to store */ 351 " xor %[value32], %[xor_value], %[value32] \n" 352 " stwcx. %[value32], 0, %[dest_base] \n" 353 " bne- 1b \n" 354 /* exit */ 355 "2: \n" 356 /* out */ 357 : [old_value] "=&r" (old_value), 358 [value32] "=&r" (value32), 359 "=m" (*dest), 360 "=m" (*dest_base) 361 /* in */ 362 : [dest] "b" (dest), 363 [dest_base] "b" (dest_base), 364 [shift_amount] "r" (shift_amount), 365 [masked_compare_val] "r" (masked_compare_val), 366 [xor_value] "r" (xor_value), 367 "m" (*dest), 368 "m" (*dest_base) 369 /* clobber */ 370 : "cc", 371 "memory" 372 ); 373 374 cmpxchg_post_membar(order); 375 376 return PrimitiveConversions::cast<T>((unsigned char)old_value); 377} 378 379template<> 380template<typename T> 381inline T Atomic::PlatformCmpxchg<4>::operator()(T exchange_value, 382 T volatile* dest, 383 T compare_value, 384 cmpxchg_memory_order order) const { 385 STATIC_ASSERT(4 == sizeof(T)); 386 387 // Note that cmpxchg guarantees a two-way memory barrier across 388 // the cmpxchg, so it's really a a 'fence_cmpxchg_fence' if not 389 // specified otherwise (see atomic.hpp). 390 391 T old_value; 392 const uint64_t zero = 0; 393 394 cmpxchg_pre_membar(order); 395 396 __asm__ __volatile__ ( 397 /* simple guard */ 398 " lwz %[old_value], 0(%[dest]) \n" 399 " cmpw %[compare_value], %[old_value] \n" 400 " bne- 2f \n" 401 /* atomic loop */ 402 "1: \n" 403 " lwarx %[old_value], %[dest], %[zero] \n" 404 " cmpw %[compare_value], %[old_value] \n" 405 " bne- 2f \n" 406 " stwcx. %[exchange_value], %[dest], %[zero] \n" 407 " bne- 1b \n" 408 /* exit */ 409 "2: \n" 410 /* out */ 411 : [old_value] "=&r" (old_value), 412 "=m" (*dest) 413 /* in */ 414 : [dest] "b" (dest), 415 [zero] "r" (zero), 416 [compare_value] "r" (compare_value), 417 [exchange_value] "r" (exchange_value), 418 "m" (*dest) 419 /* clobber */ 420 : "cc", 421 "memory" 422 ); 423 424 cmpxchg_post_membar(order); 425 426 return old_value; 427} 428 429template<> 430template<typename T> 431inline T Atomic::PlatformCmpxchg<8>::operator()(T exchange_value, 432 T volatile* dest, 433 T compare_value, 434 cmpxchg_memory_order order) const { 435 STATIC_ASSERT(8 == sizeof(T)); 436 437 // Note that cmpxchg guarantees a two-way memory barrier across 438 // the cmpxchg, so it's really a a 'fence_cmpxchg_fence' if not 439 // specified otherwise (see atomic.hpp). 440 441 T old_value; 442 const uint64_t zero = 0; 443 444 cmpxchg_pre_membar(order); 445 446 __asm__ __volatile__ ( 447 /* simple guard */ 448 " ld %[old_value], 0(%[dest]) \n" 449 " cmpd %[compare_value], %[old_value] \n" 450 " bne- 2f \n" 451 /* atomic loop */ 452 "1: \n" 453 " ldarx %[old_value], %[dest], %[zero] \n" 454 " cmpd %[compare_value], %[old_value] \n" 455 " bne- 2f \n" 456 " stdcx. %[exchange_value], %[dest], %[zero] \n" 457 " bne- 1b \n" 458 /* exit */ 459 "2: \n" 460 /* out */ 461 : [old_value] "=&r" (old_value), 462 "=m" (*dest) 463 /* in */ 464 : [dest] "b" (dest), 465 [zero] "r" (zero), 466 [compare_value] "r" (compare_value), 467 [exchange_value] "r" (exchange_value), 468 "m" (*dest) 469 /* clobber */ 470 : "cc", 471 "memory" 472 ); 473 474 cmpxchg_post_membar(order); 475 476 return old_value; 477} 478 479#undef strasm_sync 480#undef strasm_lwsync 481#undef strasm_isync 482#undef strasm_release 483#undef strasm_acquire 484#undef strasm_fence 485#undef strasm_nobarrier 486#undef strasm_nobarrier_clobber_memory 487 488#endif // OS_CPU_LINUX_PPC_VM_ATOMIC_LINUX_PPC_HPP 489