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Diffstat (limited to 'tools/perf/arch/x86/util/tsc.c')
-rw-r--r--tools/perf/arch/x86/util/tsc.c18
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;
}