aboutsummaryrefslogtreecommitdiffstats
path: root/erts/emulator/sys/unix/erl_unix_sys.h
diff options
context:
space:
mode:
Diffstat (limited to 'erts/emulator/sys/unix/erl_unix_sys.h')
-rw-r--r--erts/emulator/sys/unix/erl_unix_sys.h30
1 files changed, 29 insertions, 1 deletions
diff --git a/erts/emulator/sys/unix/erl_unix_sys.h b/erts/emulator/sys/unix/erl_unix_sys.h
index 0352ee1b3c..9f137048de 100644
--- a/erts/emulator/sys/unix/erl_unix_sys.h
+++ b/erts/emulator/sys/unix/erl_unix_sys.h
@@ -101,6 +101,10 @@
#endif
#include <netdb.h>
+#ifdef HAVE_MACH_ABSOLUTE_TIME
+#include <mach/mach_time.h>
+#endif
+
#ifdef HAVE_POSIX_MEMALIGN
# define ERTS_HAVE_ERTS_SYS_ALIGNED_ALLOC 1
#endif
@@ -266,7 +270,31 @@ erts_os_times(ErtsMonotonicTime *mtimep, ErtsSystemTime *stimep)
#endif /* ERTS_HAVE_OS_MONOTONIC_TIME_SUPPORT */
/*
- *
+ * Functions for getting the performance counter
+ */
+
+#if defined(__x86_64__)
+ /* available on all x86_64. Best if used when we have constant_tsc and
+ nonstop_tsc cpu features. It may have been a good idea to put the
+ cpuid instruction before the rdtsc, but I decided against it
+ because it is not really needed for msacc, and it slows it down by
+ quite a bit. As a result though, this timestamp becomes much less
+ accurate as it might be re-ordered to be executed way before this
+ function is called.
+ */
+#define sys_perf_counter(ts) do { \
+ __asm__ __volatile__ ("rdtsc\n\t" \
+ "shl $32, %%rdx\n\t" \
+ "or %%rdx, %0" : "=a" (*ts) : : "rdx"); \
+ } while(0)
+#define SYS_PERF_COUNTER_UNIT erts_perf_counter_unit()
+#else
+#define sys_perf_counter(ts) *(ts) = erts_get_perf_counter()
+#define SYS_PERF_COUNTER_UNIT 1000000000LL
+#endif
+
+/*
+ * Functions for measuring CPU time
*/
#if (defined(HAVE_GETHRVTIME) || defined(HAVE_CLOCK_GETTIME_CPU_TIME))