Introduce a new time API

The old time API is based on erlang:now/0. The major issue with
erlang:now/0 is that it was intended to be used for so many
unrelated things. This tied these unrelated operations together
and unnecessarily caused performance, scalability as well as
accuracy, and precision issues for operations that do not need
to have such issues. The new API spreads different functionality
over multiple functions in order to improve on this.

The new API consists of a number of new BIFs:
- erlang:convert_time_unit/3
- erlang:monotonic_time/0
- erlang:monotonic_time/1
- erlang:system_time/0
- erlang:system_time/1
- erlang:time_offset/0
- erlang:time_offset/1
- erlang:timestamp/0
- erlang:unique_integer/0
- erlang:unique_integer/1
- os:system_time/0
- os:system_time/1

and a number of extensions of existing BIFs:
- erlang:monitor(time_offset, clock_service)
- erlang:system_flag(time_offset, finalize)
- erlang:system_info(os_monotonic_time_source)
- erlang:system_info(time_offset)
- erlang:system_info(time_warp_mode)
- erlang:system_info(time_correction)
- erlang:system_info(start_time)

See the "Time and Time Correction in Erlang" chapter of the
ERTS User's Guide for more information.

1 files changed, 3 insertions, 2 deletions

diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index c505c44905..54f1a122c4 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -49,6 +49,7 @@
 #include "beam_bp.h"
 #include "erl_ptab.h"
 #include "erl_check_io.h"
+#include "erl_bif_unique.h"
 
 #undef M_TRIM_THRESHOLD
 #undef M_TOP_PAD
@@ -4353,8 +4354,8 @@ erts_smp_ensure_later_interval_acqb(erts_interval_t *icp, Uint64 ic)
  */
 Uint64 erts_timestamp_millis(void)
 {
-#ifdef HAVE_GETHRTIME
-    return (Uint64) (sys_gethrtime() / 1000000);
+#ifdef ERTS_HAVE_OS_MONOTONIC_TIME_SUPPORT
+    return ERTS_MONOTONIC_TO_MSEC(erts_os_monotonic_time());
 #else
     Uint64 res;
     SysTimeval tv;