From 20d0ea70c2f87193757263295f3e873f7f65f425 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Tue, 26 Mar 2019 22:03:48 -0700
Subject: [PATCH] ircd::ios: Add tsc counters to hook state.

---
 include/ircd/ios.h |  3 +++
 ircd/ios.cc        | 15 ++++++++++++++-
 modules/console.cc |  2 ++
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/include/ircd/ios.h b/include/ircd/ios.h
index 3a134d285..8fdf579d5 100644
--- a/include/ircd/ios.h
+++ b/include/ircd/ios.h
@@ -78,6 +78,8 @@ struct ircd::ios::descriptor
 	uint64_t alloc_bytes{0};
 	uint64_t frees {0};
 	uint64_t free_bytes{0};
+	uint64_t slice_total {0};
+	uint64_t slice_last {0};
 
 	descriptor(const string_view &name);
 	descriptor(descriptor &&) = delete;
@@ -94,6 +96,7 @@ struct ircd::ios::handler
 	static bool fault(handler *const &);
 
 	ios::descriptor *descriptor;
+	uint64_t slice_start {0};
 };
 
 template<class function>
diff --git a/ircd/ios.cc b/ircd/ios.cc
index 8fed68ca1..f0ddc9958 100644
--- a/ircd/ios.cc
+++ b/ircd/ios.cc
@@ -144,7 +144,17 @@ ircd::ios::handler::fault(handler *const &handler)
 	assert(handler && handler->descriptor);
 	auto &descriptor(*handler->descriptor);
 	++descriptor.faults;
-	return false;
+	bool ret(false);
+
+	// leave() isn't called if we return false so the tsc counter
+	// needs to be tied off here instead.
+	if(!ret)
+	{
+		descriptor.slice_last = rdtsc() - handler->slice_start;
+		descriptor.slice_total += descriptor.slice_last;
+	}
+
+	return ret;
 }
 
 void
@@ -152,6 +162,8 @@ ircd::ios::handler::leave(handler *const &handler)
 {
 	assert(handler && handler->descriptor);
 	auto &descriptor(*handler->descriptor);
+	descriptor.slice_last = rdtsc() - handler->slice_start;
+	descriptor.slice_total += descriptor.slice_last;
 }
 
 void
@@ -160,6 +172,7 @@ ircd::ios::handler::enter(handler *const &handler)
 	assert(handler && handler->descriptor);
 	auto &descriptor(*handler->descriptor);
 	++descriptor.calls;
+	handler->slice_start = rdtsc();
 }
 
 void
diff --git a/modules/console.cc b/modules/console.cc
index 72fba0e33..b6f644bca 100644
--- a/modules/console.cc
+++ b/modules/console.cc
@@ -811,6 +811,7 @@ console_cmd__ios(opt &out, const string_view &line)
 	    << " " << std::left << std::setw(48) << "NAME"
 	    << " " << std::right << std::setw(6) << "FAULTS"
 	    << " " << std::right << std::setw(10) << "CALLS"
+	    << " " << std::right << std::setw(15) << "CYCLES"
 	    << " " << std::right << std::setw(10) << "ALLOCS"
 	    << " " << std::right << std::setw(10) << "FREES"
 	    << " " << std::right << std::setw(26) << "ALLOCATED"
@@ -827,6 +828,7 @@ console_cmd__ios(opt &out, const string_view &line)
 		    << " " << std::left << std::setw(48) << d.name
 		    << " " << std::right << std::setw(6) << d.faults
 		    << " " << std::right << std::setw(10) << d.calls
+		    << " " << std::right << std::setw(15) << d.slice_total
 		    << " " << std::right << std::setw(10) << d.allocs
 		    << " " << std::right << std::setw(10) << d.frees
 		    << " " << std::right << std::setw(26) << pretty(iec(d.alloc_bytes))