8358590: JFR: Include min and max in MethodTiming event

Reviewed-by: mgronlun

Author: egahlin

src/hotspot/share/jfr/metadata/metadata.xml

@@ -1315,7 +1315,9 @@
   <Event name="MethodTiming" category="Java Application" label="Method Timing" thread="false" stackTrace="false" startTime="false" period="everyChunk">
     <Field type="Method" name="method" label="Method" />
     <Field type="long" name="invocations" label="Invocations" description="The number of times the method was invoked" />
-    <Field type="Tickspan" name="average" label="Average" description="An approximation of the wall-clock time it took for the method to execute" />
+    <Field type="Tickspan" name="minimum" label="Minimum" description="An approximation of the minimum wall-clock time it took for the method to execute" />
+    <Field type="Tickspan" name="average" label="Average" description="An approximation of the average wall-clock time it took for the method to execute" />
+    <Field type="Tickspan" name="maximum" label="Maximum" description="An approximation of the maximum wall-clock time it took for the method to execute" />
   </Event>
 
   <Type name="DeoptimizationReason" label="Deoptimization Reason">

src/jdk.jfr/share/classes/jdk/jfr/events/MethodTimingEvent.java

@@ -42,11 +42,19 @@ public final class MethodTimingEvent extends AbstractJDKEvent {
     @Label("Invocations")
     public long invocations;
 
+    @Label("Minimum Time")
+    @Timespan(Timespan.TICKS)
+    public long minimum;
+
     @Label("Average Time")
     @Timespan(Timespan.TICKS)
     public long average;
 
-    public static void commit(long start, long method, long invocations, long average) {
+    @Label("Maximum Time")
+    @Timespan(Timespan.TICKS)
+    public long maximum;
+
+    public static void commit(long start, long method, long invocations, long minimum, long average, long maximum) {
         // Generated by JFR
     }
 

src/jdk.jfr/share/classes/jdk/jfr/internal/query/view.ini

@@ -471,9 +471,9 @@ table = "COLUMN 'Alloc. Time', 'Application Method', 'Object Age', 'Heap Usage'
 
 [application.method-timing]
 label = "Method Timing"
-table = "COLUMN 'Timed Method', 'Invocations', 'Average Time'
+table = "COLUMN 'Timed Method', 'Invocations', 'Min. Tim', 'Max. Time', 'Average Time'
          FORMAT none, none, ms-precision:6
-         SELECT LAST_BATCH(method) AS M, LAST_BATCH(invocations), LAST_BATCH(average)
+         SELECT LAST_BATCH(method) AS M, LAST_BATCH(invocations), LAST_BATCH(minimum), LAST_BATCH(maximum), LAST_BATCH(average)
          FROM jdk.MethodTiming GROUP BY method ORDER BY average"
 
 [application.method-calls]

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/PlatformTracer.java

@@ -146,13 +146,15 @@ public static void emitTiming() {
     public static void addObjectTiming(long duration) {
         OBJECT.invocations().getAndIncrement();
         OBJECT.time().addAndGet(duration);
+        OBJECT.updateMinMax(duration);
     }
 
     public static void addTiming(long id, long duration) {
         TimedMethod entry = timedMethods.get(id);
         if (entry != null) {
             entry.invocations().getAndIncrement();
             entry.time().addAndGet(duration);
+            entry.updateMinMax(duration);
         }
     }
 

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/TimedClass.java

@@ -61,7 +61,12 @@ public void emit(long timestamp) {
                 long invocations = tm.invocations().get();
                 long time = tm.time().get();
                 long average = invocations == 0 ? Long.MIN_VALUE : time / invocations;
-                MethodTimingEvent.commit(timestamp, methodId, invocations, average);
+                long min = tm.minimum().get();
+                if (min == Long.MAX_VALUE) {
+                    min = Long.MIN_VALUE; // Signals that the value is missing
+                }
+                long max = tm.maximum().get();
+                MethodTimingEvent.commit(timestamp, methodId, invocations, min, average, max);
                 tm.method().log("Emitted event");
             }
         }

src/jdk.jfr/share/classes/jdk/jfr/internal/tracing/TimedMethod.java

@@ -33,8 +33,33 @@
  * <p>
  * Fields in record classes are truly final so might help to have a record here.
  */
-record TimedMethod(AtomicLong invocations, AtomicLong time, Method method, AtomicBoolean published) {
+record TimedMethod(AtomicLong invocations, AtomicLong time, AtomicLong minimum, AtomicLong maximum, Method method, AtomicBoolean published) {
     TimedMethod(Method method) {
-        this(new AtomicLong(), new AtomicLong(), method, new AtomicBoolean());
+        this(new AtomicLong(), new AtomicLong(), new AtomicLong(Long.MAX_VALUE), new AtomicLong(Long.MIN_VALUE), method, new AtomicBoolean());
+    }
+
+    public void updateMinMax(long duration) {
+        if (duration > maximum.getPlain()) {
+            while (true) {
+                long max = maximum.get();
+                if (duration <= max) {
+                    return;
+                }
+                if (maximum.weakCompareAndSetVolatile(max, duration)) {
+                    return;
+                }
+            }
+        }
+        if (duration < minimum.getPlain()) {
+            while (true) {
+                long min = minimum.get();
+                if (duration >= min) {
+                    return;
+                }
+                if (minimum.weakCompareAndSetVolatile(min, duration)) {
+                    return;
+                }
+            }
+        }
     }
 }