Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / x86 / kernel / trace_clock.c

diff --git a/kernel/arch/x86/kernel/trace_clock.c b/kernel/arch/x86/kernel/trace_clock.c
new file mode 100644 (file)
index 0000000..25b9937
--- /dev/null
+++ b/kernel/arch/x86/kernel/trace_clock.c
@@ -0,0 +1,21 @@
+/*
+ * X86 trace clocks
+ */
+#include <asm/trace_clock.h>
+#include <asm/barrier.h>
+#include <asm/msr.h>
+
+/*
+ * trace_clock_x86_tsc(): A clock that is just the cycle counter.
+ *
+ * Unlike the other clocks, this is not in nanoseconds.
+ */
+u64 notrace trace_clock_x86_tsc(void)
+{
+       u64 ret;
+
+       rdtsc_barrier();
+       rdtscll(ret);
+
+       return ret;
+}