8301749: Tracking malloc pooled memory size

Reviewed-by: dholmes, stuefe

src/hotspot/os/linux/mallocInfoDcmd.cpp

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "mallocInfoDcmd.hpp"
+#include "os_linux.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/ostream.hpp"
+
+#include <malloc.h>
+
+constexpr const char* malloc_info_unavailable = "Error: malloc_info(3) not available.";
+
+void MallocInfoDcmd::execute(DCmdSource source, TRAPS) {
+#ifdef __GLIBC__
+  char* buf;
+  size_t size;
+  ALLOW_C_FUNCTION(::open_memstream, FILE* stream = ::open_memstream(&buf, &size);)
+  if (stream == nullptr) {
+    _output->print_cr("Error: Could not call malloc_info(3)");
+    return;
+  }
+
+  int err = os::Linux::malloc_info(stream);
+  if (err == 0) {
+    ALLOW_C_FUNCTION(::fflush, fflush(stream);)
+    _output->print_raw(buf);
+    _output->cr();
+  } else if (err == -1) {
+    _output->print_cr("Error: %s", os::strerror(errno));
+  } else if (err == -2) {
+    _output->print_cr(malloc_info_unavailable);
+  } else {
+    ShouldNotReachHere();
+  }
+  ALLOW_C_FUNCTION(::fclose, ::fclose(stream);)
+  ALLOW_C_FUNCTION(::free, ::free(buf);)
+#else
+  _output->print_cr(malloc_info_unavailable);
+#endif // __GLIBC__
+}

src/hotspot/os/linux/mallocInfoDcmd.hpp

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef OS_LINUX_MALLOCINFODCMD_HPP
+#define OS_LINUX_MALLOCINFODCMD_HPP
+
+#include "services/diagnosticCommand.hpp"
+
+class outputStream;
+
+class MallocInfoDcmd : public DCmd {
+public:
+  MallocInfoDcmd(outputStream* output, bool heap) : DCmd(output, heap) {}
+  static const char* name() {
+    return "System.native_heap_info";
+  }
+  static const char* description() {
+    return "Attempts to output information regarding native heap usage through malloc_info(3). If unsuccessful outputs \"Error: \" and a reason.";
+  }
+  static const char* impact() {
+    return "Low";
+  }
+  static const JavaPermission permission() {
+    JavaPermission p = { "java.lang.management.ManagementPermission", "monitor", nullptr };
+    return p;
+  }
+  void execute(DCmdSource source, TRAPS) override;
+};
+
+#endif // OS_LINUX_MALLOCINFODCMD_HPP

src/hotspot/os/linux/os_linux.cpp

@@ -200,6 +200,9 @@ struct new_mallinfo {
 };
 typedef struct new_mallinfo (*mallinfo2_func_t)(void);
 static mallinfo2_func_t g_mallinfo2 = nullptr;
+
+typedef int (*malloc_info_func_t)(int options, FILE *stream);
+static malloc_info_func_t g_malloc_info = nullptr;
 #endif // __GLIBC__
 
 static int clock_tics_per_sec = 100;
@@ -4297,6 +4300,7 @@ void os::init(void) {
 #ifdef __GLIBC__
   g_mallinfo = CAST_TO_FN_PTR(mallinfo_func_t, dlsym(RTLD_DEFAULT, "mallinfo"));
   g_mallinfo2 = CAST_TO_FN_PTR(mallinfo2_func_t, dlsym(RTLD_DEFAULT, "mallinfo2"));
+  g_malloc_info = CAST_TO_FN_PTR(malloc_info_func_t, dlsym(RTLD_DEFAULT, "malloc_info"));
 #endif // __GLIBC__
 
   os::Linux::CPUPerfTicks pticks;
@@ -5388,6 +5392,13 @@ void os::Linux::get_mallinfo(glibc_mallinfo* out, bool* might_have_wrapped) {
     ShouldNotReachHere();
   }
 }
+
+int os::Linux::malloc_info(FILE* stream) {
+  if (g_malloc_info == nullptr) {
+    return -2;
+  }
+  return g_malloc_info(0, stream);
+}
 #endif // __GLIBC__
 
 bool os::trim_native_heap(os::size_change_t* rss_change) {

src/hotspot/os/linux/os_linux.hpp

@@ -424,6 +424,10 @@ class os::Linux {
     size_t keepcost;
   };
   static void get_mallinfo(glibc_mallinfo* out, bool* might_have_wrapped);
+
+  // Calls out to GNU extension malloc_info if available
+  // otherwise does nothing and returns -2.
+  static int malloc_info(FILE* stream);
 #endif // GLIBC
 };
 

src/hotspot/share/services/diagnosticCommand.cpp

@@ -63,6 +63,7 @@
 #include "utilities/macros.hpp"
 #ifdef LINUX
 #include "trimCHeapDCmd.hpp"
+#include "mallocInfoDcmd.hpp"
 #endif
 
 static void loadAgentModule(TRAPS) {
@@ -126,6 +127,7 @@ void DCmdRegistrant::register_dcmds(){
 #ifdef LINUX
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<PerfMapDCmd>(full_export, true, false));
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<TrimCLibcHeapDCmd>(full_export, true, false));
+  DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<MallocInfoDcmd>(full_export, true, false));
 #endif // LINUX
   DCmdFactory::register_DCmdFactory(new DCmdFactoryImpl<CodeHeapAnalyticsDCmd>(full_export, true, false));
 

src/jdk.jcmd/share/man/jcmd.1

@@ -775,6 +775,15 @@ Stops the remote management agent.
 Impact: Low --- no impact
 .RE
 .TP
+\f[V]System.native_heap_info\f[R] (Linux only)
+Prints information about native heap usage through malloc_info(3).
+.RS
+.PP
+Impact: Low
+.PP
+Permission: \f[V]java.lang.management.ManagementPermission(monitor)\f[R]
+.RE
+.TP
 \f[V]System.trim_native_heap\f[R] (Linux only)
 Attempts to free up memory by trimming the C-heap.
 .RS

test/hotspot/jtreg/serviceability/dcmd/vm/MallocInfoTest.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import jdk.test.lib.Platform;
+import org.testng.annotations.Test;
+import jdk.test.lib.dcmd.CommandExecutor;
+import jdk.test.lib.dcmd.JMXExecutor;
+import jdk.test.lib.process.OutputAnalyzer;
+
+/*
+ * @test
+ * @summary Test of diagnostic command System.native_heap_info
+ * @library /test/lib
+ * @requires (os.family=="linux")
+ * @modules java.base/jdk.internal.misc
+ *          java.compiler
+ *          java.management
+ *          jdk.internal.jvmstat/sun.jvmstat.monitor
+ * @run testng MallocInfoTest
+ */
+public class MallocInfoTest {
+    public void run(CommandExecutor executor) {
+        OutputAnalyzer output = executor.execute("System.native_heap_info");
+        if (!Platform.isMusl()) {
+            output.shouldNotContain("Error: ");
+            output.shouldContain("<malloc version=");
+        } else {
+            output.shouldContain("Error: malloc_info(3) not available.");
+        }
+        output.reportDiagnosticSummary();
+    }
+
+    @Test
+    public void jmx() {
+        run(new JMXExecutor());
+    }
+}