Add sanity checks for profiler

build-logic/conventions/src/main/kotlin/com/datadoghq/native/config/ConfigurationPresets.kt

@@ -149,7 +149,13 @@ object ConfigurationPresets {
                 config.compilerArgs.set(
                     listOf("-O0", "-g", "-DDEBUG") + commonLinuxCompilerArgs(version)
                 )
-                config.linkerArgs.set(commonLinuxLinkerArgs())
+                // -z,nodelete: same as configureRelease. Without it, the JVM (observed
+                // on OpenJ9's DestroyJavaVM path) can unmap this library while a
+                // profiler-spawned thread (via the patched pthread_create hook in
+                // LibraryPatcher) is still executing wrapper code inside it, causing a
+                // SIGSEGV with no hs_err. nodelete pins the mapping for the process's
+                // lifetime no matter how many times the host dlcloses it.
+                config.linkerArgs.set(commonLinuxLinkerArgs() + listOf("-Wl,-z,nodelete"))
             }
             Platform.MACOS -> {
                 config.compilerArgs.set(

ddprof-lib/src/main/cpp/arguments.cpp

@@ -410,6 +410,22 @@ Error Arguments::parse(const char *args) {
           }
       }
 
+      CASE("nosanity")
+      if (value != NULL) {
+        switch (value[0]) {
+        case 'n': // no
+        case 'f': // false
+        case '0': // 0
+          _skip_sanity_checks = false;
+          break;
+        default:
+          _skip_sanity_checks = true;
+        }
+      } else {
+        // A bare 'nosanity' with no value skips the checks.
+        _skip_sanity_checks = true;
+      }
+
       CASE("nativemem")
       _nativemem = value == NULL ? 0 : parseUnits(value, BYTES);
       if (_nativemem < 0) {

ddprof-lib/src/main/cpp/arguments.h

@@ -193,6 +193,7 @@ class Arguments {
   bool _lightweight;
   bool _enable_method_cleanup;
   bool _remote_symbolication;  // Enable remote symbolication for native frames
+  bool _skip_sanity_checks;
   bool _jvmtistacks;           // Delegate CPU/wall stack walks to HotSpot JFR RequestStackTrace extension
   bool _nativesocket;
   long _nativesocket_interval;  // initial sampling period in nanoseconds; 0 = engine default
@@ -234,6 +235,7 @@ class Arguments {
         _lightweight(false),
         _enable_method_cleanup(true),
         _remote_symbolication(false),
+        _skip_sanity_checks(false),
         _jvmtistacks(false),
         _nativesocket(false),
         _nativesocket_interval(0),

ddprof-lib/src/main/cpp/flightRecorder.cpp

@@ -1212,6 +1212,12 @@ void Recording::writeSettings(Buffer *buf, Arguments &args) {
                      Log::LEVEL_NAME[Log::level()]);
   writeBoolSetting(buf, T_ACTIVE_RECORDING, "hotspot", VM::isHotspot());
   writeBoolSetting(buf, T_ACTIVE_RECORDING, "openj9", VM::isOpenJ9());
+  writeBoolSetting(buf, T_ACTIVE_RECORDING, "sanityCheckFailed",
+                   Profiler::instance()->sanityCheckFailed());
+  if (Profiler::instance()->sanityCheckFailed()) {
+    writeStringSetting(buf, T_ACTIVE_RECORDING, "sanityCheckDetail",
+                       Profiler::instance()->sanityCheckMessage());
+  }
   for (auto attribute : args._context_attributes) {
     writeStringSetting(buf, T_ACTIVE_RECORDING, "contextattribute",
                        attribute.c_str());

ddprof-lib/src/main/cpp/os.h

@@ -210,6 +210,8 @@ class OS {
 
     static bool getCpuDescription(char* buf, size_t size);
     static int getCpuCount();
+    static int getCgroupCpuMillicores();
+    static long getContainerMemoryLimit();
     static u64 getProcessCpuTime(u64* utime, u64* stime);
     static u64 getTotalCpuTime(u64* utime, u64* stime);