Race on late initializing crash tracking results JVM to crash

Author: zhengyu123

dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/Agent.java

@@ -63,6 +63,7 @@
 import java.net.MalformedURLException;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.nio.ByteBuffer;
 import java.security.CodeSource;
 import java.util.EnumSet;
 import java.util.concurrent.TimeUnit;
@@ -183,7 +184,6 @@ public boolean isEnabledByDefault() {
   private static boolean codeOriginEnabled = false;
   private static boolean distributedDebuggerEnabled = false;
   private static boolean agentlessLogSubmissionEnabled = false;
-
   /**
    * Starts the agent; returns a boolean indicating if Agent started successfully
    *
@@ -795,6 +795,10 @@ private static void startCrashTracking() {
       if (forceEarlyStart) {
         initializeCrashTrackingDefault();
       } else {
+        // To workaround JDK-8345810, we want to initialize nio early,
+        // which has dependence on libpthread. Creating a small nio ByteBuffer
+        // to force nio initialization.
+        ByteBuffer buffer = ByteBuffer.allocate(1);
         AgentTaskScheduler.get().execute(Agent::initializeCrashTrackingDefault);
       }
     } else {

dd-java-agent/src/main/java/datadog/trace/bootstrap/AgentBootstrap.java

@@ -4,6 +4,7 @@
 
 import datadog.trace.bootstrap.environment.EnvironmentVariables;
 import datadog.trace.bootstrap.environment.JavaVirtualMachine;
+import datadog.trace.bootstrap.environment.OperatingSystem;
 import datadog.trace.bootstrap.environment.SystemProperties;
 import de.thetaphi.forbiddenapis.SuppressForbidden;
 import java.io.BufferedReader;
@@ -61,7 +62,7 @@ public final class AgentBootstrap {
     // On Linux, libpthread must be loaded and initialized
     // while in single threaded mode.
     try {
-      if ("Linux".equals(System.getProperty("os.name"))) {
+      if (OperatingSystem.isLinux()) {
         System.loadLibrary("nio");
       }
     } catch (Exception e) {