terminate unwinding at call_stub

DataDog · Jan 19, 2024 · 150934c · 150934c
1 parent fe05e97
commit 150934c
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Showing 4 changed files with 60 additions and 3 deletions.
diff --git a/ddprof-lib/src/main/cpp/profiler.cpp b/ddprof-lib/src/main/cpp/profiler.cpp
@@ -690,7 +690,7 @@ void Profiler::recordSample(void* ucontext, u64 counter, int tid, jint event_typ
         ASGCT_CallFrame *native_stop = frames + num_frames;
         num_frames += getNativeTrace(ucontext, native_stop, event_type, tid, &java_ctx, &truncated);
         if (_cstack == CSTACK_VM) {
-            num_frames += StackWalker::walkVM(ucontext, frames + num_frames, _max_stack_depth);
+            num_frames += StackWalker::walkVM(ucontext, frames + num_frames, _max_stack_depth, _call_stub_begin, _call_stub_end);
         } else if (event_type == BCI_CPU || event_type == BCI_WALL) {
             int java_frames = 0;
             {

diff --git a/ddprof-lib/src/main/cpp/stackWalker.cpp b/ddprof-lib/src/main/cpp/stackWalker.cpp
@@ -217,7 +217,8 @@ int StackWalker::walkDwarf(void* ucontext, const void** callchain, int max_depth
     return depth;
 }
 
-int StackWalker::walkVM(void* ucontext, ASGCT_CallFrame* frames, int max_depth) {
+int StackWalker::walkVM(void* ucontext, ASGCT_CallFrame* frames, int max_depth,
+                        const void* _termination_frame_begin, const void* _termination_frame_end) {
     const void* pc;
     uintptr_t fp;
     uintptr_t sp;
@@ -257,6 +258,9 @@ int StackWalker::walkVM(void* ucontext, ASGCT_CallFrame* frames, int max_depth)
 
     // Walk until the bottom of the stack or until the first Java frame
     while (depth < max_depth) {
+        if (pc >= _termination_frame_begin && pc < _termination_frame_end) {
+            break;
+        }
         if (CodeHeap::contains(pc)) {
             NMethod* nm = CodeHeap::findNMethod(pc);
             if (nm == NULL) {

diff --git a/ddprof-lib/src/main/cpp/stackWalker.h b/ddprof-lib/src/main/cpp/stackWalker.h
@@ -37,7 +37,7 @@ class StackWalker {
   public:
     static int walkFP(void* ucontext, const void** callchain, int max_depth, StackContext* java_ctx, bool *truncated);
     static int walkDwarf(void* ucontext, const void** callchain, int max_depth, StackContext* java_ctx, bool *truncated);
-    static int walkVM(void* ucontext, ASGCT_CallFrame* frames, int max_depth);
+    static int walkVM(void* ucontext, ASGCT_CallFrame* frames, int max_depth, const void* _termination_frame_begin, const void* _termination_frame_end);
 
     static void checkFault();
 };

diff --git a/ddprof-test/src/test/java/com/datadoghq/profiler/cpu/VMStructsBasedCpuTest.java b/ddprof-test/src/test/java/com/datadoghq/profiler/cpu/VMStructsBasedCpuTest.java
@@ -0,0 +1,53 @@
+package com.datadoghq.profiler.cpu;
+
+import com.datadoghq.profiler.AbstractProfilerTest;
+import com.datadoghq.profiler.Platform;
+import org.junit.jupiter.api.Test;
+import org.openjdk.jmc.common.item.IItem;
+import org.openjdk.jmc.common.item.IItemCollection;
+import org.openjdk.jmc.common.item.IItemIterable;
+import org.openjdk.jmc.common.item.IMemberAccessor;
+import org.openjdk.jmc.flightrecorder.jdk.JdkAttributes;
+
+import java.util.concurrent.ExecutionException;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
+
+public class VMStructsBasedCpuTest extends AbstractProfilerTest {
+
+    private ProfiledCode profiledCode;
+
+    @Override
+    protected void before() {
+        profiledCode = new ProfiledCode(profiler);
+    }
+
+    @Test
+    public void test() throws ExecutionException, InterruptedException {
+        for (int i = 0, id = 1; i < 100; i++, id += 3) {
+            profiledCode.method1(id);
+        }
+        stopProfiler();
+        IItemCollection events = verifyEvents("datadog.ExecutionSample");
+        for (IItemIterable it : events) {
+            IMemberAccessor<String, IItem> stackTraceAccessor = JdkAttributes.STACK_TRACE_STRING.getAccessor(it.getType());
+            for (IItem item : it) {
+                String stacktrace = stackTraceAccessor.getMember(item);
+                assertFalse(stacktrace.contains("JavaCalls::call_virtual()"),
+                        "JavaCalls::call_virtual() (above call_stub) found in stack trace");
+                assertFalse(stacktrace.contains("call_stub()"),
+                        "call_stub() (sentinel value used to halt unwinding) found in stack trace");
+            }
+        }
+    }
+
+    @Override
+    protected String getProfilerCommand() {
+        return "cpu=10ms" + (vmstructsUnwinderSupported() ? ",cstack=vm" : "");
+    }
+
+    private boolean vmstructsUnwinderSupported() {
+        return !Platform.isJ9() && !Platform.isZing();
+    }
+}