diff options
Diffstat (limited to 'erts/lib_src')
| -rw-r--r-- | erts/lib_src/common/ethr_aux.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/erts/lib_src/common/ethr_aux.c b/erts/lib_src/common/ethr_aux.c index fbd870c2b5..3e7aad16c7 100644 --- a/erts/lib_src/common/ethr_aux.c +++ b/erts/lib_src/common/ethr_aux.c @@ -144,16 +144,33 @@ x86_init(void) eax = 0x80000000; ethr_x86_cpuid__(&eax, &ebx, &ecx, &edx); - if (eax >= 0x80000001) { - /* Get the extended feature set */ - eax = 0x80000001; + if (eax < 0x80000001) + return; + + if (eax >= 0x80000007) { + /* Advanced Power Management Information */ + eax = 0x80000007; ethr_x86_cpuid__(&eax, &ebx, &ecx, &edx); - } else { - eax = ebx = ecx = edx = 0; + + /* I got the values below from: + http://lxr.free-electrons.com/source/arch/x86/include/asm/cpufeature.h + They can be gotten from the intel/amd manual as well. + */ + + ethr_runtime__.conf.have_constant_tsc = (edx & (1 << 8)); + ethr_runtime__.conf.have_tsc_reliable = (edx & (1 << 23)); + ethr_runtime__.conf.have_nonstop_tsc = (edx & (1 << 24)); + ethr_runtime__.conf.have_nonstop_tsc_s3 = (edx & (1 << 30)); + } - + + /* Extended Processor Info and Feature Bits */ + eax = 0x80000001; + ethr_x86_cpuid__(&eax, &ebx, &ecx, &edx); + /* bit 27 of edx is set if we have rdtscp */ ethr_runtime__.conf.have_rdtscp = (edx & (1 << 27)); + } #endif /* ETHR_X86_RUNTIME_CONF__ */ |