projects / fio.git / blame
| Commit | Line | Data |
|---|---|---|
| fa80feae JA |
1 | #ifndef FIO_ARCH_X86_COMMON |
| 2 | #define FIO_ARCH_X86_COMMON | |
| 3 | ||
| 4 | static inline void do_cpuid(unsigned int *eax, unsigned int *ebx, | |
| 5 | unsigned int *ecx, unsigned int *edx) | |
| 6 | { | |
| 267339ff JA |
7 | asm volatile("cpuid" |
| 8 | : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx) | |
| 9 | : "0" (*eax), "2" (*ecx) | |
| 10 | : "memory"); | |
| fa80feae JA |
11 | } |
| 12 | ||
| 13 | #define ARCH_HAVE_INIT | |
| 14 | extern int tsc_reliable; | |
| 15 | static inline int arch_init(char *envp[]) | |
| 16 | { | |
| 267339ff | 17 | unsigned int eax, ebx, ecx = 0, edx; |
| fa80feae JA |
18 | |
| 19 | /* | |
| 20 | * Check for TSC | |
| 21 | */ | |
| 22 | eax = 1; | |
| 23 | do_cpuid(&eax, &ebx, &ecx, &edx); | |
| 24 | if (!(edx & (1U << 4))) | |
| 25 | return 0; | |
| 26 | ||
| 27 | /* | |
| 28 | * Check for constant rate and synced (across cores) TSC | |
| 29 | */ | |
| 30 | eax = 0x80000007; | |
| 31 | do_cpuid(&eax, &ebx, &ecx, &edx); | |
| 32 | tsc_reliable = edx & (1U << 8); | |
| 33 | return 0; | |
| 34 | } | |
| 35 | ||
| 36 | #endif |