lib: Replace uhd::get_system_time() with steady_clock

Benchmarks show that using C++ chrono features beats
uhd::get_system_time(), and the latter is simply not appropriate unless
a uhd::time_spec_t is required.

2 files changed, 14 insertions, 9 deletions

diff --git a/host/lib/include/uhdlib/usrp/common/recv_packet_demuxer_3000.hpp b/host/lib/include/uhdlib/usrp/common/recv_packet_demuxer_3000.hpp
index 3a17b864e..54ae10908 100644
--- a/host/lib/include/uhdlib/usrp/common/recv_packet_demuxer_3000.hpp
+++ b/host/lib/include/uhdlib/usrp/common/recv_packet_demuxer_3000.hpp
@@ -8,7 +8,6 @@
 #ifndef INCLUDED_LIBUHD_USRP_COMMON_RECV_PACKET_DEMUXER_3000_HPP
 #define INCLUDED_LIBUHD_USRP_COMMON_RECV_PACKET_DEMUXER_3000_HPP
 
-#include <uhdlib/utils/system_time.hpp>
 #include <uhd/config.hpp>
 #include <uhd/transport/zero_copy.hpp>
 #include <uhd/utils/log.hpp>
@@ -18,6 +17,7 @@
 #include <boost/enable_shared_from_this.hpp>
 #include <queue>
 #include <map>
+#include <chrono>
 #include <stdint.h>
 
 namespace uhd{ namespace usrp{
@@ -36,15 +36,19 @@ namespace uhd{ namespace usrp{
 
         transport::managed_recv_buffer::sptr get_recv_buff(const uint32_t sid, const double timeout)
         {
-            const time_spec_t exit_time =
-                time_spec_t(timeout) + uhd::get_system_time();
+            const auto exit_time = std::chrono::high_resolution_clock::now()
+                                   + std::chrono::microseconds(int64_t(timeout * 1e6));
             transport::managed_recv_buffer::sptr buff;
             buff = _internal_get_recv_buff(sid, timeout);
             while (not buff) //loop until timeout
             {
-                const time_spec_t delta = exit_time - uhd::get_system_time();
-                const double new_timeout = delta.get_real_secs();
-                if (new_timeout < 0.0) break;
+                const auto delta = exit_time - std::chrono::high_resolution_clock::now();
+                const double new_timeout =
+                    std::chrono::duration_cast<std::chrono::duration<double>>(delta)
+                        .count();
+                if (new_timeout < 0.0) {
+                    break;
+                }
                 buff = _internal_get_recv_buff(sid, new_timeout);
             }
             return buff;
diff --git a/host/lib/include/uhdlib/utils/atomic.hpp b/host/lib/include/uhdlib/utils/atomic.hpp
index 5436eea81..303df1bc9 100644
--- a/host/lib/include/uhdlib/utils/atomic.hpp
+++ b/host/lib/include/uhdlib/utils/atomic.hpp
@@ -10,9 +10,9 @@
 
 #include <uhd/config.hpp>
 #include <uhd/types/time_spec.hpp>
-#include <uhdlib/utils/system_time.hpp>
 #include <boost/thread/thread.hpp>
 #include <atomic>
+#include <chrono>
 
 namespace uhd{
 
@@ -31,9 +31,10 @@ namespace uhd{
         const double timeout
     ){
         if (cond == value) return true;
-        const time_spec_t exit_time = uhd::get_system_time() + time_spec_t(timeout);
+        const auto exit_time = std::chrono::high_resolution_clock::now()
+                               + std::chrono::microseconds(int64_t(timeout * 1e6));
         while (cond != value) {
-            if (uhd::get_system_time() > exit_time) {
+            if (std::chrono::high_resolution_clock::now() > exit_time) {
                 return false;
             }
             boost::this_thread::interruption_point();