From 9d8fe82126ce6ed939fab61c6f6bafaad9511371 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Fri, 5 Apr 2019 16:56:51 -0700
Subject: [PATCH] ircd::prof: Add x-platform cputime reporting alternative
 interface.

---
 configure.ac        |  5 +++--
 include/ircd/prof.h | 18 +++++++++++++++--
 ircd/prof.cc        | 48 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 67 insertions(+), 4 deletions(-)

diff --git a/configure.ac b/configure.ac
index b425b0f95..277836bcb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1222,7 +1222,7 @@ dnl
 
 BOOST_VERSION_MIN="1.66"
 BOOST_VERSION_MIN_PATCH="0"
-BOOST_BUILT_LIBS="system,filesystem,context,coroutine"
+BOOST_BUILT_LIBS="system,filesystem,context,coroutine,chrono"
 
 AC_SUBST(BOOST_CPPFLAGS, [])
 AC_SUBST(BOOST_LDFLAGS, [])
@@ -1306,6 +1306,7 @@ AC_HELP_STRING([--with-included-boost[[[=shared]]]], [Use the boost sources from
 	AX_BOOST_FILESYSTEM
 	AX_BOOST_COROUTINE
 	AX_BOOST_CONTEXT
+	AX_BOOST_CHRONO
 	boost_linkage="shared"
 ])
 
@@ -1314,7 +1315,7 @@ if [[ "$boost_linkage" = "shared" ]]; then
 	[
 		AC_SUBST(BOOST_LIBS, ["-lboost_coroutine-mgw53-1_61.dll -lboost_context-mgw53-1_61.dll -lboost_thread-mgw53-1_61.dll -lboost_filesystem-mgw53-1_61.dll -lboost_system-mgw53-1_61.dll"])
 	], [
-		AC_SUBST(BOOST_LIBS, ["-lboost_coroutine -lboost_context -lboost_thread -lboost_filesystem -lboost_system"])
+		AC_SUBST(BOOST_LIBS, ["-lboost_coroutine -lboost_context -lboost_thread -lboost_filesystem -lboost_chrono -lboost_system"])
 	])
 else
 	AM_COND_IF([MINGW],
diff --git a/include/ircd/prof.h b/include/ircd/prof.h
index 4515640b7..b76b1fcc9 100644
--- a/include/ircd/prof.h
+++ b/include/ircd/prof.h
@@ -16,6 +16,7 @@ namespace ircd::prof
 	struct init;
 	struct type;
 	struct event;
+	struct times;
 	struct system;
 	enum dpl :uint8_t;
 	enum counter :uint8_t;
@@ -24,8 +25,10 @@ namespace ircd::prof
 
 	IRCD_EXCEPTION(ircd::error, error)
 
-	// Monotonic reference cycles
-	uint64_t cycles();
+	uint64_t cycles();      ///< Monotonic reference cycles (since system boot)
+	uint64_t time_user();   ///< Nanoseconds of CPU time in userspace.
+	uint64_t time_kern();   ///< Nanoseconds of CPU time in kernelland.
+	uint64_t time_real();   ///< Nanoseconds of CPU time real.
 
 	// Observe
 	system &hotsample(system &) noexcept;
@@ -54,6 +57,17 @@ namespace ircd
 	using prof::cycles;
 }
 
+struct ircd::prof::times
+{
+	uint64_t real {0};
+	uint64_t kern {0};
+	uint64_t user {0};
+
+	IRCD_OVERLOAD(sample)
+	times(sample_t);
+	times() = default;
+};
+
 struct ircd::prof::system
 :std::array<std::array<uint64_t, 2>, 7>
 {
diff --git a/ircd/prof.cc b/ircd/prof.cc
index ec7829938..fdbfddeeb 100644
--- a/ircd/prof.cc
+++ b/ircd/prof.cc
@@ -12,6 +12,8 @@
 #include <RB_INC_SYS_IOCTL_H
 #include <RB_INC_SYS_MMAN_H
 #include <linux/perf_event.h>
+#include <boost/chrono/chrono.hpp>
+#include <boost/chrono/process_cpu_clocks.hpp>
 
 namespace ircd::prof
 {
@@ -646,3 +648,49 @@ ircd::prof::debug(std::ostream &s,
 
 	return s;
 }
+
+//
+// Interface (cross-platform)
+//
+
+uint64_t
+ircd::prof::time_real()
+{
+	return boost::chrono::process_real_cpu_clock::now().time_since_epoch().count();
+}
+
+uint64_t
+ircd::prof::time_kern()
+{
+	return boost::chrono::process_system_cpu_clock::now().time_since_epoch().count();
+}
+
+uint64_t
+ircd::prof::time_user()
+{
+	return boost::chrono::process_user_cpu_clock::now().time_since_epoch().count();
+}
+
+//
+// times
+//
+
+ircd::prof::times::times(sample_t)
+:real{}
+,kern{}
+,user{}
+{
+	const auto tp
+	{
+		boost::chrono::process_cpu_clock::now()
+	};
+
+	const auto d
+	{
+		tp.time_since_epoch()
+	};
+
+	this->real = d.count().real;
+	this->kern = d.count().system;
+	this->user = d.count().user;
+}