serval-dna/nacl/nacl-20110221/cpucycles/amd64cpuspeed.c
Daniel O'Connor bf9710fd5a Unpacked nacl-20110221 after processing by nacl-prepare-sources.
This only affects build_android, if nacl-gcc-prep is run then build/`uname -s` will be created.
2012-02-27 12:40:14 +10:30

26 lines
552 B
C

#include <stdio.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/sysctl.h>
long long cpucycles_amd64cpuspeed(void)
{
unsigned long long result;
asm volatile(".byte 15;.byte 49;shlq $32,%%rdx;orq %%rdx,%%rax"
: "=a" (result) :: "%rdx");
return result;
}
long long cpucycles_amd64cpuspeed_persecond(void)
{
int oid[2];
int val;
size_t size;
oid[0] = CTL_HW;
oid[1] = HW_CPUSPEED;
size = sizeof val;
if (sysctl(oid,2,&val,&size,0,0) == -1) return 0;
if (size != sizeof val) return 0;
return val * 1000000LL;
}