1#ifndef _ASM_X86_PERCPU_H 2#define _ASM_X86_PERCPU_H 3 4#ifdef CONFIG_X86_64 5#define __percpu_seg gs 6#define __percpu_mov_op movq 7#else 8#define __percpu_seg fs 9#define __percpu_mov_op movl 10#endif 11 12#ifdef __ASSEMBLY__ 13 14/* 15 * PER_CPU finds an address of a per-cpu variable. 16 * 17 * Args: 18 * var - variable name 19 * reg - 32bit register 20 * 21 * The resulting address is stored in the "reg" argument. 22 * 23 * Example: 24 * PER_CPU(cpu_gdt_descr, %ebx) 25 */ 26#ifdef CONFIG_SMP 27#define PER_CPU(var, reg) \ 28 __percpu_mov_op %__percpu_seg:this_cpu_off, reg; \ 29 lea var(reg), reg 30#define PER_CPU_VAR(var) %__percpu_seg:var 31#else /* ! SMP */ 32#define PER_CPU(var, reg) __percpu_mov_op $var, reg 33#define PER_CPU_VAR(var) var 34#endif /* SMP */ 35 36#ifdef CONFIG_X86_64_SMP 37#define INIT_PER_CPU_VAR(var) init_per_cpu__##var 38#else 39#define INIT_PER_CPU_VAR(var) var 40#endif 41 42#else /* ...!ASSEMBLY */ 43 44#include <linux/kernel.h> 45#include <linux/stringify.h> 46 47#ifdef CONFIG_SMP 48#define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x 49#define __my_cpu_offset percpu_read(this_cpu_off) 50#else 51#define __percpu_arg(x) "%P" #x 52#endif 53 54/* 55 * Initialized pointers to per-cpu variables needed for the boot 56 * processor need to use these macros to get the proper address 57 * offset from __per_cpu_load on SMP. 58 * 59 * There also must be an entry in vmlinux_64.lds.S 60 */ 61#define DECLARE_INIT_PER_CPU(var) \ 62 extern typeof(var) init_per_cpu_var(var) 63 64#ifdef CONFIG_X86_64_SMP 65#define init_per_cpu_var(var) init_per_cpu__##var 66#else 67#define init_per_cpu_var(var) var 68#endif 69 70/* For arch-specific code, we can use direct single-insn ops (they 71 * don't give an lvalue though). */ 72extern void __bad_percpu_size(void); 73 74#define percpu_to_op(op, var, val) \ 75do { \ 76 typedef typeof(var) pto_T__; \ 77 if (0) { \ 78 pto_T__ pto_tmp__; \ 79 pto_tmp__ = (val); \ 80 (void)pto_tmp__; \ 81 } \ 82 switch (sizeof(var)) { \ 83 case 1: \ 84 asm(op "b %1,"__percpu_arg(0) \ 85 : "+m" (var) \ 86 : "qi" ((pto_T__)(val))); \ 87 break; \ 88 case 2: \ 89 asm(op "w %1,"__percpu_arg(0) \ 90 : "+m" (var) \ 91 : "ri" ((pto_T__)(val))); \ 92 break; \ 93 case 4: \ 94 asm(op "l %1,"__percpu_arg(0) \ 95 : "+m" (var) \ 96 : "ri" ((pto_T__)(val))); \ 97 break; \ 98 case 8: \ 99 asm(op "q %1,"__percpu_arg(0) \ 100 : "+m" (var) \ 101 : "re" ((pto_T__)(val))); \ 102 break; \ 103 default: __bad_percpu_size(); \ 104 } \ 105} while (0) 106 107/* 108 * Generate a percpu add to memory instruction and optimize code 109 * if one is added or subtracted. 110 */ 111#define percpu_add_op(var, val) \ 112do { \ 113 typedef typeof(var) pao_T__; \ 114 const int pao_ID__ = (__builtin_constant_p(val) && \ 115 ((val) == 1 || (val) == -1)) ? (val) : 0; \ 116 if (0) { \ 117 pao_T__ pao_tmp__; \ 118 pao_tmp__ = (val); \ 119 (void)pao_tmp__; \ 120 } \ 121 switch (sizeof(var)) { \ 122 case 1: \ 123 if (pao_ID__ == 1) \ 124 asm("incb "__percpu_arg(0) : "+m" (var)); \ 125 else if (pao_ID__ == -1) \ 126 asm("decb "__percpu_arg(0) : "+m" (var)); \ 127 else \ 128 asm("addb %1, "__percpu_arg(0) \ 129 : "+m" (var) \ 130 : "qi" ((pao_T__)(val))); \ 131 break; \ 132 case 2: \ 133 if (pao_ID__ == 1) \ 134 asm("incw "__percpu_arg(0) : "+m" (var)); \ 135 else if (pao_ID__ == -1) \ 136 asm("decw "__percpu_arg(0) : "+m" (var)); \ 137 else \ 138 asm("addw %1, "__percpu_arg(0) \ 139 : "+m" (var) \ 140 : "ri" ((pao_T__)(val))); \ 141 break; \ 142 case 4: \ 143 if (pao_ID__ == 1) \ 144 asm("incl "__percpu_arg(0) : "+m" (var)); \ 145 else if (pao_ID__ == -1) \ 146 asm("decl "__percpu_arg(0) : "+m" (var)); \ 147 else \ 148 asm("addl %1, "__percpu_arg(0) \ 149 : "+m" (var) \ 150 : "ri" ((pao_T__)(val))); \ 151 break; \ 152 case 8: \ 153 if (pao_ID__ == 1) \ 154 asm("incq "__percpu_arg(0) : "+m" (var)); \ 155 else if (pao_ID__ == -1) \ 156 asm("decq "__percpu_arg(0) : "+m" (var)); \ 157 else \ 158 asm("addq %1, "__percpu_arg(0) \ 159 : "+m" (var) \ 160 : "re" ((pao_T__)(val))); \ 161 break; \ 162 default: __bad_percpu_size(); \ 163 } \ 164} while (0) 165 166#define percpu_from_op(op, var, constraint) \ 167({ \ 168 typeof(var) pfo_ret__; \ 169 switch (sizeof(var)) { \ 170 case 1: \ 171 asm(op "b "__percpu_arg(1)",%0" \ 172 : "=q" (pfo_ret__) \ 173 : constraint); \ 174 break; \ 175 case 2: \ 176 asm(op "w "__percpu_arg(1)",%0" \ 177 : "=r" (pfo_ret__) \ 178 : constraint); \ 179 break; \ 180 case 4: \ 181 asm(op "l "__percpu_arg(1)",%0" \ 182 : "=r" (pfo_ret__) \ 183 : constraint); \ 184 break; \ 185 case 8: \ 186 asm(op "q "__percpu_arg(1)",%0" \ 187 : "=r" (pfo_ret__) \ 188 : constraint); \ 189 break; \ 190 default: __bad_percpu_size(); \ 191 } \ 192 pfo_ret__; \ 193}) 194 195#define percpu_unary_op(op, var) \ 196({ \ 197 switch (sizeof(var)) { \ 198 case 1: \ 199 asm(op "b "__percpu_arg(0) \ 200 : "+m" (var)); \ 201 break; \ 202 case 2: \ 203 asm(op "w "__percpu_arg(0) \ 204 : "+m" (var)); \ 205 break; \ 206 case 4: \ 207 asm(op "l "__percpu_arg(0) \ 208 : "+m" (var)); \ 209 break; \ 210 case 8: \ 211 asm(op "q "__percpu_arg(0) \ 212 : "+m" (var)); \ 213 break; \ 214 default: __bad_percpu_size(); \ 215 } \ 216}) 217 218/* 219 * percpu_read() makes gcc load the percpu variable every time it is 220 * accessed while percpu_read_stable() allows the value to be cached. 221 * percpu_read_stable() is more efficient and can be used if its value 222 * is guaranteed to be valid across cpus. The current users include 223 * get_current() and get_thread_info() both of which are actually 224 * per-thread variables implemented as per-cpu variables and thus 225 * stable for the duration of the respective task. 226 */ 227#define percpu_read(var) percpu_from_op("mov", var, "m" (var)) 228#define percpu_read_stable(var) percpu_from_op("mov", var, "p" (&(var))) 229#define percpu_write(var, val) percpu_to_op("mov", var, val) 230#define percpu_add(var, val) percpu_add_op(var, val) 231#define percpu_sub(var, val) percpu_add_op(var, -(val)) 232#define percpu_and(var, val) percpu_to_op("and", var, val) 233#define percpu_or(var, val) percpu_to_op("or", var, val) 234#define percpu_xor(var, val) percpu_to_op("xor", var, val) 235#define percpu_inc(var) percpu_unary_op("inc", var) 236 237#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 238#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 239#define __this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 240 241#define __this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val) 242#define __this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val) 243#define __this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val) 244#define __this_cpu_add_1(pcp, val) percpu_add_op((pcp), val) 245#define __this_cpu_add_2(pcp, val) percpu_add_op((pcp), val) 246#define __this_cpu_add_4(pcp, val) percpu_add_op((pcp), val) 247#define __this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val) 248#define __this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val) 249#define __this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val) 250#define __this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val) 251#define __this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val) 252#define __this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val) 253#define __this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val) 254#define __this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val) 255#define __this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val) 256 257#define this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 258#define this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 259#define this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 260#define this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val) 261#define this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val) 262#define this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val) 263#define this_cpu_add_1(pcp, val) percpu_add_op((pcp), val) 264#define this_cpu_add_2(pcp, val) percpu_add_op((pcp), val) 265#define this_cpu_add_4(pcp, val) percpu_add_op((pcp), val) 266#define this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val) 267#define this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val) 268#define this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val) 269#define this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val) 270#define this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val) 271#define this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val) 272#define this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val) 273#define this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val) 274#define this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val) 275 276#define irqsafe_cpu_add_1(pcp, val) percpu_add_op((pcp), val) 277#define irqsafe_cpu_add_2(pcp, val) percpu_add_op((pcp), val) 278#define irqsafe_cpu_add_4(pcp, val) percpu_add_op((pcp), val) 279#define irqsafe_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val) 280#define irqsafe_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val) 281#define irqsafe_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val) 282#define irqsafe_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val) 283#define irqsafe_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val) 284#define irqsafe_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val) 285#define irqsafe_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val) 286#define irqsafe_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val) 287#define irqsafe_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val) 288 289/* 290 * Per cpu atomic 64 bit operations are only available under 64 bit. 291 * 32 bit must fall back to generic operations. 292 */ 293#ifdef CONFIG_X86_64 294#define __this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 295#define __this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val) 296#define __this_cpu_add_8(pcp, val) percpu_add_op((pcp), val) 297#define __this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val) 298#define __this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val) 299#define __this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val) 300 301#define this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 302#define this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val) 303#define this_cpu_add_8(pcp, val) percpu_add_op((pcp), val) 304#define this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val) 305#define this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val) 306#define this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val) 307 308#define irqsafe_cpu_add_8(pcp, val) percpu_add_op((pcp), val) 309#define irqsafe_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val) 310#define irqsafe_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val) 311#define irqsafe_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val) 312 313#endif 314 315/* This is not atomic against other CPUs -- CPU preemption needs to be off */ 316#define x86_test_and_clear_bit_percpu(bit, var) \ 317({ \ 318 int old__; \ 319 asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \ 320 : "=r" (old__), "+m" (var) \ 321 : "dIr" (bit)); \ 322 old__; \ 323}) 324 325#include <asm-generic/percpu.h> 326 327/* We can use this directly for local CPU (faster). */ 328DECLARE_PER_CPU(unsigned long, this_cpu_off); 329 330#endif /* !__ASSEMBLY__ */ 331 332#ifdef CONFIG_SMP 333 334/* 335 * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu 336 * variables that are initialized and accessed before there are per_cpu 337 * areas allocated. 338 */ 339 340#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \ 341 DEFINE_PER_CPU(_type, _name) = _initvalue; \ 342 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \ 343 { [0 ... NR_CPUS-1] = _initvalue }; \ 344 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map 345 346#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \ 347 EXPORT_PER_CPU_SYMBOL(_name) 348 349#define DECLARE_EARLY_PER_CPU(_type, _name) \ 350 DECLARE_PER_CPU(_type, _name); \ 351 extern __typeof__(_type) *_name##_early_ptr; \ 352 extern __typeof__(_type) _name##_early_map[] 353 354#define early_per_cpu_ptr(_name) (_name##_early_ptr) 355#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx]) 356#define early_per_cpu(_name, _cpu) \ 357 *(early_per_cpu_ptr(_name) ? \ 358 &early_per_cpu_ptr(_name)[_cpu] : \ 359 &per_cpu(_name, _cpu)) 360 361#else /* !CONFIG_SMP */ 362#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \ 363 DEFINE_PER_CPU(_type, _name) = _initvalue 364 365#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \ 366 EXPORT_PER_CPU_SYMBOL(_name) 367 368#define DECLARE_EARLY_PER_CPU(_type, _name) \ 369 DECLARE_PER_CPU(_type, _name) 370 371#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu) 372#define early_per_cpu_ptr(_name) NULL 373/* no early_per_cpu_map() */ 374 375#endif /* !CONFIG_SMP */ 376 377#endif /* _ASM_X86_PERCPU_H */ 378