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Diffstat (limited to '')
-rw-r--r-- | tools/perf/arch/x86/util/cpuid.h | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/tools/perf/arch/x86/util/cpuid.h b/tools/perf/arch/x86/util/cpuid.h new file mode 100644 index 000000000..0a3ae0ace --- /dev/null +++ b/tools/perf/arch/x86/util/cpuid.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef PERF_CPUID_H +#define PERF_CPUID_H 1 + + +static inline void +cpuid(unsigned int op, unsigned int op2, unsigned int *a, unsigned int *b, + unsigned int *c, unsigned int *d) +{ + /* + * Preserve %ebx/%rbx register by either placing it in %rdi or saving it + * on the stack - x86-64 needs to avoid the stack red zone. In PIC + * compilations %ebx contains the address of the global offset + * table. %rbx is occasionally used to address stack variables in + * presence of dynamic allocas. + */ + asm( +#if defined(__x86_64__) + "mov %%rbx, %%rdi\n" + "cpuid\n" + "xchg %%rdi, %%rbx\n" +#else + "pushl %%ebx\n" + "cpuid\n" + "movl %%ebx, %%edi\n" + "popl %%ebx\n" +#endif + : "=a"(*a), "=D"(*b), "=c"(*c), "=d"(*d) + : "a"(op), "2"(op2)); +} + +void get_cpuid_0(char *vendor, unsigned int *lvl); + +#endif |