Some architectures have special purpose registers to query the system
counter's frequency. Let's use that when available.
Signed-off-by: Nicolas Saenz Julienne <nsaenzju@xxxxxxxxxx>
--
Changes since v1:
- Use cleaner method to have generic and arch functions to measure
couter's freq
src/oslat/oslat.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/src/oslat/oslat.c b/src/oslat/oslat.c
index c90ec1a..5fce223 100644
--- a/src/oslat/oslat.c
+++ b/src/oslat/oslat.c
@@ -74,6 +74,16 @@ static inline void frc(uint64_t *pval)
# elif defined(__aarch64__)
# define relax() __asm__ __volatile("yield" : : : "memory")
+#define arch_measure_counter_mhz
+static unsigned int measure_counter_mhz(void)
+{
+ unsigned int val;
+
+ __asm__ __volatile__("mrs %0, cntfrq_el0" : "=r" (val));
+
+ return val / 1e6;
+}
+
static inline void frc(uint64_t *pval)
{
/*
@@ -241,6 +251,7 @@ static int move_to_core(int core_i)
return sched_setaffinity(0, sizeof(cpus), &cpus);
}
+#ifndef arch_measure_counter_mhz
static cycles_t __measure_counter_hz(void)
{
struct timeval tvs, tve;
@@ -273,6 +284,7 @@ static unsigned int measure_counter_mhz(void)
return (unsigned int) (m / 1000000);
}
+#endif
static void thread_init(struct thread *t)
{
--
2.31.1
