LTTng hotspot and hotspot private tracepoints

dev-tracing/lttng_examples/test/Main.java

@@ -0,0 +1,6 @@
+public class Main {
+
+    public static void main(String[] args) {
+        System.out.println("Hello world");
+    }
+}

dev-tracing/lttng_examples/test/run.sh

@@ -0,0 +1,21 @@
+jdkPath="../../../build/linux-x86_64-server-release/images/jdk/bin"
+
+$jdkPath/javac Main.java
+
+
+lttng create test-session --output=./here
+lttng enable-event -u 'hotspot:*' --channel=channel1
+lttng enable-event -u 'hs_private:*' --channel=channel2
+# lttng enable-event -k --userspace-probe=sdt:$jdkPath/../lib/server/libjvm.so:hotspot:method__entry --channel=channel1 entry
+lttng start
+
+$jdkPath/java -XX:+DTraceMethodProbes Main
+
+
+lttng stop
+lttng view
+
+lttng destroy test-session
+
+
+

make/autoconf/configure.ac

@@ -205,6 +205,7 @@ JDKOPT_SETUP_ADDRESS_SANITIZER
 
 # Need toolchain to setup dtrace
 HOTSPOT_SETUP_DTRACE
+HOTSPOT_SETUP_LTTNG
 HOTSPOT_ENABLE_DISABLE_AOT
 HOTSPOT_ENABLE_DISABLE_CDS
 HOTSPOT_ENABLE_DISABLE_GTEST

make/autoconf/hotspot.m4

@@ -24,7 +24,7 @@
 #
 
 # All valid JVM features, regardless of platform
-VALID_JVM_FEATURES="compiler1 compiler2 zero minimal dtrace jvmti jvmci \
+VALID_JVM_FEATURES="compiler1 compiler2 zero minimal dtrace lttng jvmti jvmci \
     graal vm-structs jni-check services management cmsgc epsilongc g1gc parallelgc serialgc shenandoahgc zgc nmt cds \
     static-build link-time-opt aot jfr"
 
@@ -199,6 +199,23 @@ AC_DEFUN_ONCE([HOTSPOT_SETUP_DTRACE],
   fi
 ])
 
+###############################################################################
+# Check if lttng should be enabled.
+#
+AC_DEFUN_ONCE([HOTSPOT_SETUP_LTTNG],
+[
+
+  AC_ARG_ENABLE([lttng], [AS_HELP_STRING([--enable-lttng],
+      [enable lttng hotspot tracepoints.])], [lttng_enabled=yes])
+
+  INCLUDE_LTTNG=true
+  if test "x$INCLUDE_DTRACE" = "xtrue" && test "$INCLUDE_LTTNG" = "xtrue"; then
+    AC_MSG_ERROR([dtrace and lttng can not be included at the same time])
+  fi
+])
+
+
+
 ################################################################################
 # Check if AOT should be enabled
 #
@@ -363,14 +380,22 @@ AC_DEFUN_ONCE([HOTSPOT_SETUP_JVM_FEATURES],
     DISABLED_JVM_FEATURES="$DISABLED_JVM_FEATURES epsilongc g1gc zgc shenandoahgc"
   fi
 
-  # Turn on additional features based on other parts of configure
+ Turn on additional features based on other parts of configure
   if test "x$INCLUDE_DTRACE" = "xtrue"; then
     JVM_FEATURES="$JVM_FEATURES dtrace"
   else
     if HOTSPOT_CHECK_JVM_FEATURE(dtrace); then
       AC_MSG_ERROR([To enable dtrace, you must use --enable-dtrace])
     fi
   fi
+
+  if test "x$INCLUDE_LTTNG" = "xtrue"; then
+    JVM_FEATURES="$JVM_FEATURES lttng"
+  else
+    if HOTSPOT_CHECK_JVM_FEATURE(lttng); then
+      AC_MSG_ERROR([To enable lttng, you must use --enable-lttng])
+    fi
+  fi
 
   if test "x$STATIC_BUILD" = "xtrue"; then
     JVM_FEATURES="$JVM_FEATURES static-build"

make/autoconf/libraries.m4

@@ -130,6 +130,10 @@ AC_DEFUN_ONCE([LIB_SETUP_LIBRARIES],
     BASIC_JVM_LIBS="$BASIC_JVM_LIBS -lthread"
   fi
 
+  if test "x$INCLUDE_LTTNG" = xtrue; then
+    BASIC_JVM_LIBS="$BASIC_JVM_LIBS -ldl -llttng-ust" 
+  fi 
+
   # perfstat lib
   if test "x$OPENJDK_TARGET_OS" = xaix; then
     BASIC_JVM_LIBS="$BASIC_JVM_LIBS -lperfstat"

make/hotspot/lib/JvmFeatures.gmk

@@ -67,6 +67,10 @@ ifeq ($(call check-jvm-feature, dtrace), true)
   JVM_CFLAGS_FEATURES += -DDTRACE_ENABLED
 endif
 
+ifeq ($(call check-jvm-feature, lttng), true)
+    JVM_CFLAGS_FEATURES += -DLTTNG_ENABLED
+endif
+
 ifeq ($(call check-jvm-feature, static-build), true)
   JVM_CFLAGS_FEATURES += -DSTATIC_BUILD=1
 endif

src/hotspot/share/utilities/dtrace.hpp

@@ -50,6 +50,14 @@
 #include "dtracefiles/hotspot_jni.h"
 #include "dtracefiles/hs_private.h"
 
+#elif defined(LTTNG_ENABLED)
+
+#include "utilities/lttng.hpp"
+#define DTRACE_ONLY(x) x
+#define NOT_DTRACE(x)
+
+#define HS_DTRACE_WORKAROUND_TAIL_CALL_BUG()
+
 #else /* defined(DTRACE_ENABLED) */
 
 #define DTRACE_ONLY(x)

src/hotspot/share/utilities/dtrace_disabled.hpp

@@ -129,7 +129,7 @@
 #define HS_PRIVATE_CMS_REMARK_BEGIN_ENABLED() 0
 #define HS_PRIVATE_CMS_REMARK_END()
 #define HS_PRIVATE_CMS_REMARK_END_ENABLED() 0
-#define HS_PRIVATE_HASHTABLE_NEW_ENTRY(arg0, arg1, arg2, arg3)
+#define HS_PRIVATE_HASHTABLE_NEW_ENTRY(arg0, arg1, arg2, arg3) // does not exist
 #define HS_PRIVATE_HASHTABLE_NEW_ENTRY_ENABLED() 0
 #define HS_PRIVATE_SAFEPOINT_BEGIN()
 #define HS_PRIVATE_SAFEPOINT_BEGIN_ENABLED() 0

src/hotspot/share/utilities/lttngHSPrivate.cpp

@@ -0,0 +1,4 @@
+#define TRACEPOINT_CREATE_PROBES
+#define TRACEPOINT_DEFINE
+
+#include <utilities/lttngHSPrivate.hpp>

src/hotspot/share/utilities/lttngHSPrivate.hpp

@@ -0,0 +1,64 @@
+#if !defined(TRACEPOINT_HEADER_MULTI_READ)
+#define TRACEPOINT_HEADER_MULTI_READ
+#endif
+
+#undef TRACEPOINT_PROVIDER
+#define TRACEPOINT_PROVIDER hs_private
+
+#undef TRACEPOINT_INCLUDE
+#define TRACEPOINT_INCLUDE "./utilities/lttngHSPrivate.hpp"
+
+#if !defined(_VM_METHODS_TP_H) || defined(TRACEPOINT_HEADER_MULTI_READ)
+#define _VM_METHODS_TP_H 
+
+#include <lttng/tracepoint.h>
+
+
+/* hotspot private events */
+
+TRACEPOINT_EVENT(
+    hs_private, 
+    safepoint__begin,
+    TP_ARGS(),
+    TP_FIELDS()
+)
+
+TRACEPOINT_EVENT(
+    hs_private, 
+    safepoint__end,
+    TP_ARGS(),
+    TP_FIELDS()
+)
+
+TRACEPOINT_EVENT(
+    hs_private,
+    cms__initmark__begin,
+    TP_ARGS(),
+    TP_FIELDS()
+)
+
+TRACEPOINT_EVENT(
+    hs_private,
+    cms__initmark__end,
+    TP_ARGS(),
+    TP_FIELDS()
+)
+
+TRACEPOINT_EVENT(
+    hs_private,
+    cms__remark__begin,
+    TP_ARGS(),
+    TP_FIELDS()
+)
+
+TRACEPOINT_EVENT(
+    hs_private,
+    cms__remark__end,
+    TP_ARGS(),
+    TP_FIELDS()
+)
+
+
+#endif
+
+#include <lttng/tracepoint-event.h>

src/hotspot/share/utilities/lttngTracepoints.cpp

@@ -0,0 +1,4 @@
+#define TRACEPOINT_CREATE_PROBES
+#define TRACEPOINT_DEFINE
+
+#include <utilities/lttngTracepoints.hpp>