Simplifications and cleanups.

Pass a native memory tracking category to all relevant allocations of native memory.

Author: christianhaeubl

sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/UnmanagedMemory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -62,8 +62,7 @@ private UnmanagedMemory() {
     /**
      * Allocates {@code size} bytes of unmanaged memory. The content of the memory is undefined.
      * <p>
-     * If {@code size} is 0, the method is allowed but not required to return the null pointer. This
-     * method never returns a the null pointer, but instead throws a {@link OutOfMemoryError} when
+     * This method never returns a null pointer, but instead throws an {@link OutOfMemoryError} when
      * allocation fails.
      *
      * @since 19.0
@@ -76,19 +75,10 @@ public static <T extends PointerBase> T malloc(UnsignedWord size) {
         return result;
     }
 
-    public static <T extends PointerBase> T malloc(UnsignedWord size, int flag) {
-        T result = ImageSingletons.lookup(UnmanagedMemorySupport.class).malloc(size, flag);
-        if (result.isNull()) {
-            throw new OutOfMemoryError("malloc of unmanaged memory");
-        }
-        return result;
-    }
-
     /**
      * Allocates {@code size} bytes of unmanaged memory. The content of the memory is undefined.
      * <p>
-     * If {@code size} is 0, the method is allowed but not required to return the null pointer. This
-     * method never returns a the null pointer, but instead throws a {@link OutOfMemoryError} when
+     * This method never returns a null pointer, but instead throws an {@link OutOfMemoryError} when
      * allocation fails.
      *
      * @since 19.0
@@ -100,8 +90,7 @@ public static <T extends PointerBase> T malloc(int size) {
     /**
      * Allocates {@code size} bytes of unmanaged memory. The content of the memory is set to 0.
      * <p>
-     * If {@code size} is 0, the method is allowed but not required to return the null pointer. This
-     * method never returns a the null pointer, but instead throws a {@link OutOfMemoryError} when
+     * This method never returns a null pointer, but instead throws an {@link OutOfMemoryError} when
      * allocation fails.
      *
      * @since 19.0
@@ -117,8 +106,7 @@ public static <T extends PointerBase> T calloc(UnsignedWord size) {
     /**
      * Allocates {@code size} bytes of unmanaged memory. The content of the memory is set to 0.
      * <p>
-     * If {@code size} is 0, the method is allowed but not required to return the null pointer. This
-     * method never returns a the null pointer, but instead throws a {@link OutOfMemoryError} when
+     * This method never returns a null pointer, but instead throws an {@link OutOfMemoryError} when
      * allocation fails.
      *
      * @since 19.0
@@ -132,9 +120,8 @@ public static <T extends PointerBase> T calloc(int size) {
      * If the new size is larger than the old size, the content of the additional memory is
      * undefined.
      * <p>
-     * If {@code size} is 0, the method is allowed but not required to return the null pointer. This
-     * method never returns a the null pointer, but instead throws a {@link OutOfMemoryError} when
-     * allocation fails.
+     * This method never returns a null pointer, but instead throws an {@link OutOfMemoryError} when
+     * allocation fails. In that case, the old data is not deallocated and remains unchanged.
      *
      * @since 19.0
      */
@@ -146,29 +133,13 @@ public static <T extends PointerBase> T realloc(T ptr, UnsignedWord size) {
         return result;
     }
 
-    public static <T extends PointerBase> T realloc(T ptr, UnsignedWord size, int flag) {
-        T result = ImageSingletons.lookup(UnmanagedMemorySupport.class).realloc(ptr, size, flag);
-        if (result.isNull()) {
-            throw new OutOfMemoryError("realloc of unmanaged memory");
-        }
-        return result;
-    }
-
     /**
-     * Frees unmanaged memory that was previously allocated using methods of this class.
+     * Frees unmanaged memory that was previously allocated using methods of this class. This method
+     * is a no-op if the given pointer is {@code null}.
      *
      * @since 19.0
      */
     public static void free(PointerBase ptr) {
         ImageSingletons.lookup(UnmanagedMemorySupport.class).free(ptr);
     }
-
-    /**
-     * Will not attempt to perform any NMT operations. This is crucial for releasing memory
-     * allocated by C libraries which will not have NMT "malloc headers". If
-     * {@link UnmanagedMemory#free(PointerBase)} is used instead, a segfault will occur.
-     */
-    public static void untrackedFree(PointerBase ptr) {
-        ImageSingletons.lookup(UnmanagedMemorySupport.class).untrackedFree(ptr);
-    }
 }

sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/impl/UnmanagedMemorySupport.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2024, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -43,21 +43,13 @@
 import org.graalvm.word.PointerBase;
 import org.graalvm.word.UnsignedWord;
 
-/** Implemented by operating-system specific code. */
+/** Implemented by platform or operating-system specific code. */
 public interface UnmanagedMemorySupport {
     <T extends PointerBase> T malloc(UnsignedWord size);
 
-    <T extends PointerBase> T malloc(UnsignedWord size, int flag);
-
     <T extends PointerBase> T calloc(UnsignedWord size);
 
-    <T extends PointerBase> T calloc(UnsignedWord size, int flag);
-
     <T extends PointerBase> T realloc(T ptr, UnsignedWord size);
 
-    <T extends PointerBase> T realloc(T ptr, UnsignedWord size, int flag);
-
     void free(PointerBase ptr);
-
-    void untrackedFree(PointerBase ptr);
 }

substratevm/CHANGELOG.md

@@ -6,6 +6,7 @@ This changelog summarizes major changes to GraalVM Native Image.
 * (GR-51106) Fields that are accessed via a `VarHandle` or `MethodHandle` are no longer marked as "unsafe accessed" when the `VarHandle`/`MethodHandle` can be fully intrinsified.
 * (GR-49996) Ensure explicitly set image name (e.g., via `-o imagename`) is not accidentally overwritten by `-jar jarfile` option.
 * (GR-48683) Together with Red Hat, we added partial support for the JFR event `OldObjectSample`.
+* (GR-51851) Together with Red Hat, we added initial support for native memory tracking (`--enable-monitoring=nmt`).
 
 ## GraalVM for JDK 22 (Internal Version 24.0.0)
 * (GR-48304) Red Hat added support for the JFR event ThreadAllocationStatistics.

substratevm/src/com.oracle.svm.agent/src/com/oracle/svm/agent/BreakpointInterceptor.java

@@ -61,9 +61,6 @@
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Supplier;
 
-import com.oracle.svm.core.jni.headers.JNIMode;
-import jdk.graal.compiler.core.common.NumUtil;
-import jdk.graal.compiler.java.LambdaUtils;
 import org.graalvm.nativeimage.StackValue;
 import org.graalvm.nativeimage.UnmanagedMemory;
 import org.graalvm.nativeimage.c.function.CEntryPoint;
@@ -88,6 +85,7 @@
 import com.oracle.svm.core.jni.headers.JNIEnvironment;
 import com.oracle.svm.core.jni.headers.JNIFieldId;
 import com.oracle.svm.core.jni.headers.JNIMethodId;
+import com.oracle.svm.core.jni.headers.JNIMode;
 import com.oracle.svm.core.jni.headers.JNINativeMethod;
 import com.oracle.svm.core.jni.headers.JNIObjectHandle;
 import com.oracle.svm.core.jni.headers.JNIValue;
@@ -106,6 +104,9 @@
 import com.oracle.svm.jvmtiagentbase.jvmti.JvmtiInterface;
 import com.oracle.svm.jvmtiagentbase.jvmti.JvmtiLocationFormat;
 
+import jdk.graal.compiler.core.common.NumUtil;
+import jdk.graal.compiler.java.LambdaUtils;
+
 /**
  * Intercepts events of interest via breakpoints in Java code.
  * <p>

substratevm/src/com.oracle.svm.core.posix/src/com/oracle/svm/core/posix/PosixProcessPropertiesSupport.java

@@ -36,12 +36,12 @@
 import org.graalvm.nativeimage.c.type.CCharPointer;
 import org.graalvm.nativeimage.c.type.CTypeConversion;
 import org.graalvm.nativeimage.c.type.CTypeConversion.CCharPointerHolder;
-import org.graalvm.nativeimage.UnmanagedMemory;
 import org.graalvm.word.PointerBase;
 import org.graalvm.word.WordFactory;
 
 import com.oracle.svm.core.BaseProcessPropertiesSupport;
 import com.oracle.svm.core.graal.stackvalue.UnsafeStackValue;
+import com.oracle.svm.core.memory.UntrackedNullableNativeMemory;
 import com.oracle.svm.core.posix.headers.Dlfcn;
 import com.oracle.svm.core.posix.headers.Signal;
 import com.oracle.svm.core.posix.headers.Stdlib;
@@ -103,7 +103,7 @@ public String getObjectFile(PointerBase symbolAddress) {
         try {
             return CTypeConversion.toJavaString(realpath);
         } finally {
-            UnmanagedMemory.untrackedFree(realpath);
+            UntrackedNullableNativeMemory.free(realpath);
         }
     }
 
@@ -157,14 +157,14 @@ protected static String realpath(String path) {
          * pointer to it, so I have to free it.
          */
         try (CCharPointerHolder pathHolder = CTypeConversion.toCString(path)) {
-            final CCharPointer realpathPointer = Stdlib.realpath(pathHolder.get(), WordFactory.nullPointer());
-            if (realpathPointer.isNull()) {
+            CCharPointer realpath = Stdlib.realpath(pathHolder.get(), WordFactory.nullPointer());
+            if (realpath.isNull()) {
                 /* Failure to find a real path. */
                 return null;
             } else {
                 /* Success */
-                final String result = CTypeConversion.toJavaString(realpathPointer);
-                UnmanagedMemory.untrackedFree(realpathPointer);
+                String result = CTypeConversion.toJavaString(realpath);
+                UntrackedNullableNativeMemory.free(realpath);
                 return result;
             }
         }

substratevm/src/com.oracle.svm.core.posix/src/com/oracle/svm/core/posix/PosixRawFileOperationSupport.java

@@ -32,7 +32,6 @@
 import org.graalvm.nativeimage.Platforms;
 import org.graalvm.nativeimage.c.type.CCharPointer;
 import org.graalvm.nativeimage.c.type.CTypeConversion;
-import org.graalvm.nativeimage.impl.UnmanagedMemorySupport;
 import org.graalvm.word.Pointer;
 import org.graalvm.word.SignedWord;
 import org.graalvm.word.UnsignedWord;
@@ -42,6 +41,7 @@
 import com.oracle.svm.core.feature.AutomaticallyRegisteredFeature;
 import com.oracle.svm.core.feature.InternalFeature;
 import com.oracle.svm.core.headers.LibC;
+import com.oracle.svm.core.memory.UntrackedNullableNativeMemory;
 import com.oracle.svm.core.os.AbstractRawFileOperationSupport;
 import com.oracle.svm.core.os.AbstractRawFileOperationSupport.RawFileOperationSupportHolder;
 import com.oracle.svm.core.posix.headers.Errno;
@@ -58,7 +58,7 @@ public PosixRawFileOperationSupport(boolean useNativeByteOrder) {
     @Override
     public CCharPointer allocateCPath(String path) {
         byte[] data = path.getBytes();
-        CCharPointer filename = ImageSingletons.lookup(UnmanagedMemorySupport.class).malloc(WordFactory.unsigned(data.length + 1));
+        CCharPointer filename = UntrackedNullableNativeMemory.malloc(WordFactory.unsigned(data.length + 1));
         if (filename.isNull()) {
             return WordFactory.nullPointer();
         }