1 files changed, 30 insertions, 0 deletions
diff --git a/kernel/tools/perf/util/tsc.c b/kernel/tools/perf/util/tsc.c
new file mode 100644
index 000000000..4d4210d4e
--- /dev/null
+++ b/kernel/tools/perf/util/tsc.c
@@ -0,0 +1,30 @@
+#include <linux/compiler.h>
+#include <linux/types.h>
+
+#include "tsc.h"
+
+u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc)
+{
+	u64 t, quot, rem;
+
+	t = ns - tc->time_zero;
+	quot = t / tc->time_mult;
+	rem  = t % tc->time_mult;
+	return (quot << tc->time_shift) +
+	       (rem << tc->time_shift) / tc->time_mult;
+}
+
+u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
+{
+	u64 quot, rem;
+
+	quot = cyc >> tc->time_shift;
+	rem  = cyc & ((1 << tc->time_shift) - 1);
+	return tc->time_zero + quot * tc->time_mult +
+	       ((rem * tc->time_mult) >> tc->time_shift);
+}
+
+u64 __weak rdtsc(void)
+{
+	return 0;
+}