diff options
Diffstat (limited to 'tools/perf/arch/x86/util/tsc.c')
-rw-r--r-- | tools/perf/arch/x86/util/tsc.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/tools/perf/arch/x86/util/tsc.c b/tools/perf/arch/x86/util/tsc.c index e2d6cfe21057..3a439e4b12d2 100644 --- a/tools/perf/arch/x86/util/tsc.c +++ b/tools/perf/arch/x86/util/tsc.c @@ -24,9 +24,9 @@ u64 rdtsc(void) * ... * will return 3000000000. */ -static double cpuinfo_tsc_freq(void) +static u64 cpuinfo_tsc_freq(void) { - double result = 0; + u64 result = 0; FILE *cpuinfo; char *line = NULL; size_t len = 0; @@ -34,20 +34,22 @@ static double cpuinfo_tsc_freq(void) cpuinfo = fopen("/proc/cpuinfo", "r"); if (!cpuinfo) { pr_err("Failed to read /proc/cpuinfo for TSC frequency\n"); - return NAN; + return 0; } while (getline(&line, &len, cpuinfo) > 0) { if (!strncmp(line, "model name", 10)) { char *pos = strstr(line + 11, " @ "); + double float_result; - if (pos && sscanf(pos, " @ %lfGHz", &result) == 1) { - result *= 1000000000; + if (pos && sscanf(pos, " @ %lfGHz", &float_result) == 1) { + float_result *= 1000000000; + result = (u64)float_result; goto out; } } } out: - if (fpclassify(result) == FP_ZERO) + if (result == 0) pr_err("Failed to find TSC frequency in /proc/cpuinfo\n"); free(line); @@ -55,7 +57,7 @@ out: return result; } -double arch_get_tsc_freq(void) +u64 arch_get_tsc_freq(void) { unsigned int a, b, c, d, lvl; static bool cached; @@ -86,6 +88,6 @@ double arch_get_tsc_freq(void) return tsc; } - tsc = (double)c * (double)b / (double)a; + tsc = (u64)c * (u64)b / (u64)a; return tsc; } |