6942632: Hotspot should be able to use more than 64 logical processors on Windows

make/test/JtregNativeHotspot.gmk

@@ -1512,7 +1512,7 @@ else
   BUILD_HOTSPOT_JTREG_LIBRARIES_LIBS_libnativeStack += -lpthread
   BUILD_HOTSPOT_JTREG_EXECUTABLES_LIBS_exeGetCreatedJavaVMs := -ljvm -lpthread
 
-  BUILD_HOTSPOT_JTREG_EXCLUDE += libNativeException.c
+  BUILD_HOTSPOT_JTREG_EXCLUDE += libNativeException.c exeGetProcessorInfo.c
 endif
 
 ifeq ($(ASAN_ENABLED), true)

src/hotspot/os/windows/globals_windows.hpp

@@ -36,6 +36,9 @@
                          range,                                           \
                          constraint)                                      \
                                                                           \
+product(bool, UseAllWindowsProcessorGroups, false,                        \
+        "Use all processor groups on supported Windows versions")         \
+                                                                          \
 product(bool, UseOSErrorReporting, false,                                 \
         "Let VM fatal error propagate to the OS (ie. WER on Windows)")
 

src/hotspot/os/windows/os_windows.hpp

@@ -43,6 +43,13 @@ class os::win32 {
   static julong _physical_memory;
   static bool   _is_windows_server;
   static bool   _has_exit_bug;
+  static bool   _processor_group_warning_displayed;
+  static bool   _job_object_processor_group_warning_displayed;
+
+  static int    _major_version;
+  static int    _minor_version;
+  static int    _build_number;
+  static int    _build_minor;
 
   static void print_windows_version(outputStream* st);
   static void print_uptime_info(outputStream* st);
@@ -56,6 +63,37 @@ class os::win32 {
   // Windows-specific interface:
   static void   initialize_system_info();
   static void   setmode_streams();
+  static bool   is_windows_11_or_greater();
+  static bool   is_windows_server_2022_or_greater();
+  static int windows_major_version() {
+    assert(_major_version > 0, "windows version not initialized.");
+    return _major_version;
+  }
+  static int windows_minor_version() {
+    assert(_major_version > 0, "windows version not initialized.");
+    return _minor_version;
+  }
+  static int windows_build_number() {
+    assert(_major_version > 0, "windows version not initialized.");
+    return _build_number;
+  }
+  static int windows_build_minor() {
+    assert(_major_version > 0, "windows version not initialized.");
+    return _build_minor;
+  }
+
+  static void set_processor_group_warning_displayed(bool displayed)  {
+    _processor_group_warning_displayed = displayed;
+  }
+  static bool processor_group_warning_displayed() {
+    return _processor_group_warning_displayed;
+  }
+  static void set_job_object_processor_group_warning_displayed(bool displayed)  {
+    _job_object_processor_group_warning_displayed = displayed;
+  }
+  static bool job_object_processor_group_warning_displayed() {
+    return _job_object_processor_group_warning_displayed;
+  }
 
   // Processor info as provided by NT
   static int processor_type()  { return _processor_type;  }
@@ -79,6 +117,8 @@ class os::win32 {
   static int exit_process_or_thread(Ept what, int exit_code);
 
   static void initialize_performance_counter();
+  static void initialize_windows_version();
+  static DWORD active_processors_in_job_object(DWORD* active_processor_groups = nullptr);
 
  public:
   // Generic interface:

test/hotspot/gtest/runtime/test_os_windows.cpp

@@ -703,6 +703,25 @@ TEST_VM(os_windows, reserve_memory_special) {
   TestReserveMemorySpecial_test();
 }
 
+TEST_VM(os_windows, processor_count) {
+  JVMFlag* flag = JVMFlag::find_flag("UseAllWindowsProcessorGroups");
+  EXPECT_NE(flag, nullptr) << "Expected UseAllWindowsProcessorGroups product flag to be available";
+
+  int processors = os::processor_count();
+  EXPECT_GT(processors, 0) << "Expected at least 1 processor";
+
+  int active_processors = os::active_processor_count();
+  EXPECT_GT(active_processors, 0) << "Expected at least 1 active processor";
+
+  bool schedules_all_processor_groups = os::win32::is_windows_11_or_greater() || os::win32::is_windows_server_2022_or_greater();
+  if (schedules_all_processor_groups && UseAllWindowsProcessorGroups) {
+    EXPECT_EQ(active_processors, processors) << "Expected all processors to be active";
+  } else {
+    // active_processors should be at most the number of processors in 1 Windows processor group.
+    EXPECT_LE(active_processors, processors) << "Expected active processors to not exceed available processors";
+  }
+}
+
 class ReserveMemorySpecialRunnable : public TestRunnable {
 public:
   void runUnitTest() const {

test/hotspot/jtreg/TEST.groups

@@ -152,6 +152,7 @@ tier1_common = \
   gtest/MetaspaceGtests.java \
   gtest/LargePageGtests.java \
   gtest/NMTGtests.java \
+  gtest/WindowsProcessorGroups.java
 
 tier1_compiler = \
   :tier1_compiler_1 \

test/hotspot/jtreg/gtest/WindowsProcessorGroups.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2024, 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.
+ *
+ */
+
+/*
+ * This runs the os related gtests on Windows with all processor groups enabled.
+ */
+
+/* @test id=use-all-windows-processor-groups
+ * @summary Run gtests with all Windows processor groups enabled
+ * @library /test/lib
+ * @requires os.family == "windows"
+ * @run main/native GTestWrapper --gtest_filter=os* -XX:+UseAllWindowsProcessorGroups
+ */

test/hotspot/jtreg/runtime/os/windows/GetAvailableProcessors.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2024, 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.
+ *
+ */
+
+public class GetAvailableProcessors {
+  public static void main(String[] args) {
+    System.out.println("Runtime.availableProcessors: " + Runtime.getRuntime().availableProcessors());
+  }
+}

test/hotspot/jtreg/runtime/os/windows/TestAvailableProcessors.java

@@ -0,0 +1,218 @@
+/*
+ * Copyright (c) 2024, 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.
+ *
+ */
+
+/*
+ * @test
+ * @bug 6942632
+ * @requires os.family == "windows"
+ * @summary This test verifies that OpenJDK can use all available
+ *          processors on Windows 11/Windows Server 2022 and later.
+ * @requires vm.flagless
+ * @library /test/lib
+ * @compile GetAvailableProcessors.java
+ * @run testng TestAvailableProcessors
+ */
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.HashSet;
+import java.util.Set;
+
+import jdk.test.lib.Utils;
+import jdk.test.lib.process.OutputAnalyzer;
+import jdk.test.lib.process.ProcessTools;
+
+import org.testng.Assert;
+import org.testng.annotations.Test;
+
+public class TestAvailableProcessors {
+
+    private static final String totalProcessorCountMessage = "Active processor count across all processor groups: ";
+    private static final String processorCountPerGroupMessage = "Active processors per group: ";
+    private static final String isWindowsServerMessage = "IsWindowsServer: ";
+
+    private static final String runtimeAvailableProcessorsMessage = "Runtime.availableProcessors: ";
+    private static final String osVersionMessage = "OS Version: ";
+    private static final String unsupportedPlatformMessage = "The UseAllWindowsProcessorGroups flag is not supported on this Windows version and will be ignored.";
+
+    private static String getWindowsVersion() throws IOException {
+        String systeminfoPath = "systeminfo.exe";
+
+        var processBuilder = new ProcessBuilder(systeminfoPath);
+        OutputAnalyzer outputAnalyzer = new OutputAnalyzer(processBuilder.start());
+        outputAnalyzer.shouldHaveExitValue(0);
+        outputAnalyzer.shouldContain(osVersionMessage);
+        List<String> lines = outputAnalyzer.stdoutAsLines();
+
+        String osVersion = null;
+        for (var line: lines) {
+            if (line.startsWith(osVersionMessage)) {
+                osVersion = line.substring(osVersionMessage.length()).trim();
+                break;
+            }
+        }
+
+        System.out.println("Found OS version: " + osVersion);
+        return osVersion;
+    }
+
+    private static boolean getSchedulesAllProcessorGroups(boolean isWindowsServer) throws IOException {
+        String windowsVer = getWindowsVersion();
+        String[] parts = windowsVer.split(" ");
+        String[] versionParts = parts[0].split("\\.");
+
+        if (versionParts.length != 3) {
+            throw new RuntimeException("Unexpected Windows version format.");
+        }
+
+        int major = Integer.parseInt(versionParts[0]);
+        int minor = Integer.parseInt(versionParts[1]);
+        int build = Integer.parseInt(versionParts[2]);
+
+        if (major > 10) {
+            return true;
+        }
+
+        if (major < 10) {
+            return false;
+        }
+
+        if (minor > 0) {
+            return true;
+        }
+
+        if (isWindowsServer) {
+            return build >= 20348;
+        } else {
+            return build >= 22000;
+        }
+    }
+
+    private static OutputAnalyzer getAvailableProcessorsOutput(boolean productFlagEnabled) throws IOException {
+        String productFlag = productFlagEnabled ? "-XX:+UseAllWindowsProcessorGroups" : "-XX:-UseAllWindowsProcessorGroups";
+
+        ProcessBuilder processBuilder = ProcessTools.createLimitedTestJavaProcessBuilder(
+            new String[] {productFlag, "GetAvailableProcessors"}
+        );
+
+        var output = new OutputAnalyzer(processBuilder.start());
+        output.shouldHaveExitValue(0);
+        output.shouldContain(runtimeAvailableProcessorsMessage);
+
+        return output;
+    }
+
+    private static int getAvailableProcessors(OutputAnalyzer outputAnalyzer) {
+        int runtimeAvailableProcs = 0;
+        List<String> output = outputAnalyzer.stdoutAsLines();
+
+        for (var line: output) {
+            if (line.startsWith(runtimeAvailableProcessorsMessage)) {
+                String runtimeAvailableProcsStr = line.substring(runtimeAvailableProcessorsMessage.length());
+                runtimeAvailableProcs = Integer.parseInt(runtimeAvailableProcsStr);
+            }
+        }
+
+        return runtimeAvailableProcs;
+    }
+
+    private static int getAvailableProcessors(boolean productFlagEnabled) throws IOException {
+        OutputAnalyzer outputAnalyzer = getAvailableProcessorsOutput(productFlagEnabled);
+        return getAvailableProcessors(outputAnalyzer);
+    }
+
+    private static void verifyAvailableProcessorsWithDisabledProductFlag(Set<Integer> processorGroupSizes) throws IOException {
+        boolean productFlagEnabled = false;
+        int runtimeAvailableProcs = getAvailableProcessors(productFlagEnabled);
+
+        String error = String.format("Runtime.availableProcessors (%d) is not a valid processor group size on this machine.", runtimeAvailableProcs);
+        Assert.assertTrue(processorGroupSizes.contains(runtimeAvailableProcs), error);
+    }
+
+    private static void verifyAvailableProcessorsWithEnabledProductFlag(boolean schedulesAllProcessorGroups, int totalProcessorCount, Set<Integer> processorGroupSizes) throws IOException {
+        boolean productFlagEnabled = true;
+
+        OutputAnalyzer outputAnalyzer = getAvailableProcessorsOutput(productFlagEnabled);
+        int runtimeAvailableProcs = getAvailableProcessors(outputAnalyzer);
+
+        if (schedulesAllProcessorGroups) {
+            String error = String.format("Runtime.availableProcessors (%d) is not equal to the expected total processor count (%d)", runtimeAvailableProcs, totalProcessorCount);
+            Assert.assertEquals(runtimeAvailableProcs, totalProcessorCount, error);
+        } else {
+            outputAnalyzer.shouldContain(unsupportedPlatformMessage);
+
+            String error = String.format("Runtime.availableProcessors (%d) is not a valid processor group size on this machine.", runtimeAvailableProcs);
+            Assert.assertTrue(processorGroupSizes.contains(runtimeAvailableProcs), error);
+        }
+    }
+
+    @Test
+    private static void testProcessorAvailability() throws IOException {
+        // Launch GetProcessorInfo.exe to gather processor counts
+        Path nativeGetProcessorInfo = Paths.get(Utils.TEST_NATIVE_PATH)
+            .resolve("GetProcessorInfo.exe")
+            .toAbsolutePath();
+
+        var processBuilder = new ProcessBuilder(nativeGetProcessorInfo.toString());
+        var outputAnalyzer= new OutputAnalyzer(processBuilder.start());
+        outputAnalyzer.shouldHaveExitValue(0);
+        outputAnalyzer.shouldContain(totalProcessorCountMessage);
+        outputAnalyzer.shouldContain(processorCountPerGroupMessage);
+        outputAnalyzer.shouldContain(isWindowsServerMessage);
+
+        int totalProcessorCount = 0;
+        boolean isWindowsServer = false;
+        var processorGroupSizes = new HashSet<Integer>();
+
+        List<String> lines = outputAnalyzer.stdoutAsLines();
+
+        for (var line: lines) {
+            if (line.startsWith(totalProcessorCountMessage)) {
+                String totalProcessorCountStr = line.substring(totalProcessorCountMessage.length());
+                totalProcessorCount = Integer.parseInt(totalProcessorCountStr);
+            } else if (line.startsWith(processorCountPerGroupMessage)) {
+                String processorCountPerGroupStr = line.substring(processorCountPerGroupMessage.length());
+                String[] processorCountsPerGroup = processorCountPerGroupStr.split(",");
+
+                for (var processorCountStr: processorCountsPerGroup) {
+                    int processorCount = Integer.parseInt(processorCountStr);
+                    processorGroupSizes.add(processorCount);
+                }
+            } else if (line.startsWith(isWindowsServerMessage)) {
+                String isWindowsServerStr = line.substring(isWindowsServerMessage.length());
+                isWindowsServer = Integer.parseInt(isWindowsServerStr) > 0;
+            }
+        }
+
+        // Launch java without the start command and with the product flag disabled
+        verifyAvailableProcessorsWithDisabledProductFlag(processorGroupSizes);
+
+        // Launch java without the start command and with the product flag enabled
+        boolean schedulesAllProcessorGroups = getSchedulesAllProcessorGroups(isWindowsServer);
+        verifyAvailableProcessorsWithEnabledProductFlag(schedulesAllProcessorGroups, totalProcessorCount, processorGroupSizes);
+    }
+}