Backport 4caf2b3dccee96d3d3bf1b95972761e32e62117c to 5.16 (#21496)2018-06

2 files changed, 76 insertions, 32 deletions

diff --git a/.gitmodules b/.gitmodules
index 4e968d7a066..74cfae3eab2 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,60 +1,60 @@
 [submodule "external/aspnetwebstack"]
 	path = external/aspnetwebstack
-	url = git://github.com/mono/aspnetwebstack.git
+	url = https://github.com/mono/aspnetwebstack.git
 [submodule "external/Newtonsoft.Json"]
 	path = external/Newtonsoft.Json
-	url = git://github.com/mono/Newtonsoft.Json.git
+	url = https://github.com/mono/Newtonsoft.Json.git
 [submodule "external/cecil"]
 	path = external/cecil
-	url = git://github.com/mono/cecil.git
+	url = https://github.com/mono/cecil.git
 [submodule "external/rx"]
 	path = external/rx
-	url = git://github.com/mono/rx.git
+	url = https://github.com/mono/rx.git
 	branch = rx-oss-v2.2
 [submodule "external/ikvm"]
 	path = external/ikvm
-	url = git://github.com/mono/ikvm-fork.git
+	url = https://github.com/mono/ikvm-fork.git
 [submodule "external/ikdasm"]
 	path = external/ikdasm
-	url = git://github.com/mono/ikdasm.git
+	url = https://github.com/mono/ikdasm.git
 [submodule "external/reference-assemblies"]
 	path = external/binary-reference-assemblies
-	url = git://github.com/mono/reference-assemblies.git
+	url = https://github.com/mono/reference-assemblies.git
 [submodule "external/nunit-lite"]
 	path = external/nunit-lite
-	url = git://github.com/mono/NUnitLite.git
+	url = https://github.com/mono/NUnitLite.git
 [submodule "external/nuget-buildtasks"]
 	path = external/nuget-buildtasks
-	url = git://github.com/mono/NuGet.BuildTasks
+	url = https://github.com/mono/NuGet.BuildTasks
 [submodule "external/cecil-legacy"]
 	path = external/cecil-legacy
-	url = git://github.com/mono/cecil.git
+	url = https://github.com/mono/cecil.git
 	branch = mono-legacy-0.9.5
 [submodule "external/boringssl"]
 	path = external/boringssl
-	url = git://github.com/mono/boringssl.git
+	url = https://github.com/mono/boringssl.git
 	branch = mono
 [submodule "external/corefx"]
 	path = external/corefx
-	url = git://github.com/mono/corefx.git
+	url = https://github.com/mono/corefx.git
 [submodule "external/bockbuild"]
 	path = external/bockbuild
-	url = git://github.com/mono/bockbuild.git
+	url = https://github.com/mono/bockbuild.git
 [submodule "external/linker"]
 	path = external/linker
-	url = git://github.com/mono/linker.git
+	url = https://github.com/mono/linker.git
 [submodule "external/roslyn-binaries"]
 	path = external/roslyn-binaries
-	url = git://github.com/mono/roslyn-binaries.git
+	url = https://github.com/mono/roslyn-binaries.git
 [submodule "external/corert"]
 	path = external/corert
-	url = git://github.com/mono/corert.git
+	url = https://github.com/mono/corert.git
 [submodule "external/xunit-binaries"]
 	path = external/xunit-binaries
-	url = git://github.com/mono/xunit-binaries.git
+	url = https://github.com/mono/xunit-binaries.git
 [submodule "external/api-doc-tools"]
 	path = external/api-doc-tools
-	url = git://github.com/mono/api-doc-tools.git
+	url = https://github.com/mono/api-doc-tools.git
 [submodule "external/api-snapshot"]
 	path = external/api-snapshot
-	url = git://github.com/mono/api-snapshot.git
+	url = https://github.com/mono/api-snapshot.git
diff --git a/mono/metadata/threadpool-worker-default.c b/mono/metadata/threadpool-worker-default.c
index 33870a6de15..3779b8471f2 100644
--- a/mono/metadata/threadpool-worker-default.c
+++ b/mono/metadata/threadpool-worker-default.c
@@ -194,6 +194,14 @@ COUNTER_READ (void)
 	return counter;
 }
 
+static gint16
+counter_num_active (ThreadPoolWorkerCounter counter)
+{
+	gint16 num_active = counter._.starting + counter._.working + counter._.parked;
+	g_assert (num_active >= 0);
+	return num_active;
+}
+
 static gpointer
 rand_create (void)
 {
@@ -453,6 +461,8 @@ worker_try_unpark (void)
 	return res;
 }
 
+static void hill_climbing_force_change (gint16 new_thread_count, ThreadPoolHeuristicStateTransition transition);
+
 static gsize WINAPI
 worker_thread (gpointer unused)
 {
@@ -473,16 +483,18 @@ worker_thread (gpointer unused)
 	thread = mono_thread_internal_current ();
 	g_assert (thread);
 
+	gboolean worker_timed_out = FALSE;
 	while (!mono_runtime_is_shutting_down ()) {
 		if (mono_thread_interruption_checkpoint_bool ())
 			continue;
 
 		if (!work_item_try_pop ()) {
-			gboolean timeout;
+			gboolean const timeout = worker_park();
 
-			timeout = worker_park ();
-			if (timeout)
+			if (timeout) {
+				worker_timed_out = TRUE;
 				break;
+			}
 
 			continue;
 		}
@@ -497,6 +509,19 @@ worker_thread (gpointer unused)
 		counter._.working --;
 	});
 
+       if (worker_timed_out) {
+               gint16 decr_max_working;
+               COUNTER_ATOMIC (counter, {
+                               decr_max_working = MAX (worker.limit_worker_min, MIN (counter_num_active (counter), counter._.max_working));
+                               counter._.max_working = decr_max_working;
+               });
+               mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_THREADPOOL, "[%p] worker timed out, starting = %d working = %d parked = %d, setting max_working to %d",
+                           GUINT_TO_POINTER (MONO_NATIVE_THREAD_ID_TO_UINT (mono_native_thread_id_get ())),
+                           counter._.starting, counter._.working, counter._.parked,
+                           decr_max_working);
+               hill_climbing_force_change (decr_max_working, TRANSITION_THREAD_TIMED_OUT);
+       }
+
 	mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_THREADPOOL, "[%p] worker finishing",
 		GUINT_TO_POINTER (MONO_NATIVE_THREAD_ID_TO_UINT (mono_native_thread_id_get ())));
 
@@ -659,8 +684,6 @@ monitor_sufficient_delay_since_last_dequeue (void)
 	return mono_msec_ticks () >= worker.heuristic_last_dequeue + threshold;
 }
 
-static void hill_climbing_force_change (gint16 new_thread_count, ThreadPoolHeuristicStateTransition transition);
-
 static gsize WINAPI
 monitor_thread (gpointer unused)
 {
@@ -688,9 +711,16 @@ monitor_thread (gpointer unused)
 
 		g_assert (worker.monitor_status != MONITOR_STATUS_NOT_RUNNING);
 
-		// counter = COUNTER_READ ();
-		// printf ("monitor_thread: starting = %d working = %d parked = %d max_working = %d\n",
-		// 	counter._.starting, counter._.working, counter._.parked, counter._.max_working);
+#if 0
+		// This is ifdef'd out because otherwise we flood the log every
+		// MONITOR_INTERVAL ms, which is pretty noisy.
+		if (mono_trace_is_traced (G_LOG_LEVEL_DEBUG, MONO_TRACE_THREADPOOL)) {
+			ThreadPoolWorkerCounter trace_counter = COUNTER_READ ();
+			gint32 work_items = work_item_count ();
+			mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_THREADPOOL, "monitor_thread: work items = %d, starting = %d working = %d parked = %d max_working = %d\n",
+				    work_items, trace_counter._.starting, trace_counter._.working, trace_counter._.parked, trace_counter._.max_working);
+		}
+#endif
 
 		do {
 			gint64 ts;
@@ -721,20 +751,33 @@ monitor_thread (gpointer unused)
 		if (!monitor_sufficient_delay_since_last_dequeue ())
 			continue;
 
-		limit_worker_max_reached = FALSE;
+		gboolean active_max_reached;
 
 		COUNTER_ATOMIC (counter, {
+			limit_worker_max_reached = FALSE;
+			active_max_reached = FALSE;
 			if (counter._.max_working >= worker.limit_worker_max) {
 				limit_worker_max_reached = TRUE;
+				if (counter_num_active (counter) >= counter._.max_working)
+					active_max_reached = TRUE;
 				break;
 			}
 			counter._.max_working ++;
 		});
 
-		if (limit_worker_max_reached)
-			continue;
-
-		hill_climbing_force_change (counter._.max_working, TRANSITION_STARVATION);
+		if (limit_worker_max_reached) {
+			mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_THREADPOOL, "[%p] monitor thread, limit_worker_max (%d) reached",
+				    GUINT_TO_POINTER (MONO_NATIVE_THREAD_ID_TO_UINT (mono_native_thread_id_get ())),
+				    worker.limit_worker_max);
+			if (active_max_reached)
+				continue;
+			else
+				mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_THREADPOOL, "[%p] monitor thread, num_active (%d) < max_working, allowing active thread increase",
+					    GUINT_TO_POINTER (MONO_NATIVE_THREAD_ID_TO_UINT (mono_native_thread_id_get ())),
+					    counter_num_active (counter));
+		}
+		else
+			hill_climbing_force_change (counter._.max_working, TRANSITION_STARVATION);
 
 		for (i = 0; i < 5; ++i) {
 			if (mono_runtime_is_shutting_down ())
@@ -1093,6 +1136,7 @@ heuristic_adjust (void)
 				counter._.max_working = new_thread_count;
 			});
 
+			/* FIXME: this can never be true. we only leave COUNTER_ATOMIC() if the assignment and CAS succeeded */
 			if (new_thread_count > counter._.max_working)
 				worker_request ();