8284686: Interval of < 1 ms disables ExecutionSample events

Backport-of: 902b1dd4550136c520e5ec6cb8c4fe9a81218938

Author: parttimenerd

src/jdk.jfr/share/classes/jdk/jfr/internal/settings/PeriodSetting.java

@@ -114,10 +114,10 @@ public void setValue(String value) {
             break;
         default:
             long nanos = Utils.parseTimespanWithInfinity(value);
-            if (nanos != Long.MAX_VALUE) {
-                eventType.setPeriod(nanos / 1_000_000, false, false);
+            if (nanos == 0 || nanos == Long.MAX_VALUE) {
+                eventType.setPeriod(nanos, false, false);
             } else {
-                eventType.setPeriod(Long.MAX_VALUE, false, false);
+                eventType.setPeriod(Math.max(1, nanos / 1_000_000), false, false);
             }
         }
         this.value = value;

test/jdk/jdk/jfr/api/recording/event/TestShortPeriod.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright (c) 2022 SAP SE. 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.
+ */
+
+package jdk.jfr.api.recording.event;
+
+import java.time.Duration;
+
+import jdk.jfr.Event;
+import jdk.jfr.FlightRecorder;
+import jdk.jfr.consumer.RecordingStream;
+import jdk.test.lib.jfr.EventNames;
+
+/**
+ * @test Tests that periodic events are not disabled when using a very short
+ *       period
+ * @key jfr
+ * @requires vm.hasJFR
+ * @library /test/lib /test/jdk
+ * @run main/othervm jdk.jfr.api.recording.event.TestShortPeriod
+ */
+public class TestShortPeriod {
+
+    static class PeriodicEvent extends Event {
+    }
+
+    private static Thread startLoopingThread() {
+        var t = new Thread(() -> {
+            while (!Thread.interrupted()) {}
+        });
+        t.start();
+        return t;
+    }
+
+    public static void main(String... args) {
+        testNativeEventPeriod();
+        testJavaEventPeriod();
+        testExecutionSamplePeriod();
+    }
+
+    private static void testNativeEventPeriod() {
+        try (var r = new RecordingStream()) {
+            r.enable(EventNames.JVMInformation).withPeriod(Duration.ofNanos(1));
+            r.onEvent(e -> r.close());
+            r.start();
+        }
+    }
+
+    private static void testJavaEventPeriod() {
+        Runnable hook = () -> {
+            PeriodicEvent e = new PeriodicEvent();
+            e.commit();
+        };
+        FlightRecorder.addPeriodicEvent(PeriodicEvent.class, hook);
+        try (var r = new RecordingStream()) {
+            r.enable(PeriodicEvent.class).withPeriod(Duration.ofNanos(1));
+            r.onEvent(e -> r.close());
+            r.start();
+        }
+        FlightRecorder.removePeriodicEvent(hook);
+    }
+
+    // The execution sample event doesn't use the standard mechanism
+    // for periodic events
+    private static void testExecutionSamplePeriod() {
+        try (var r = new RecordingStream()) {
+            // start a new thread as the current thread is excluded from
+            // sample capturing to avoid recursion
+            var t = startLoopingThread();
+            r.enable(EventNames.ExecutionSample).withPeriod(Duration.ofNanos(1));
+            r.onEvent("jdk.ExecutionSample", e -> {
+                t.interrupt();
+                r.close();
+            });
+            r.start();
+        }
+    }
+}