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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef PERF_CPUID_H3#define PERF_CPUID_H 14 5 6static inline void7cpuid(unsigned int op, unsigned int op2, unsigned int *a, unsigned int *b,8 unsigned int *c, unsigned int *d)9{10 /*11 * Preserve %ebx/%rbx register by either placing it in %rdi or saving it12 * on the stack - x86-64 needs to avoid the stack red zone. In PIC13 * compilations %ebx contains the address of the global offset14 * table. %rbx is occasionally used to address stack variables in15 * presence of dynamic allocas.16 */17 asm(18#if defined(__x86_64__)19 "mov %%rbx, %%rdi\n"20 "cpuid\n"21 "xchg %%rdi, %%rbx\n"22#else23 "pushl %%ebx\n"24 "cpuid\n"25 "movl %%ebx, %%edi\n"26 "popl %%ebx\n"27#endif28 : "=a"(*a), "=D"(*b), "=c"(*c), "=d"(*d)29 : "a"(op), "2"(op2));30}31 32void get_cpuid_0(char *vendor, unsigned int *lvl);33 34#endif35