8358666: [REDO] Implement JEP 509: JFR CPU-Time Profiling

Reviewed-by: mgronlun

Author: parttimenerd

src/hotspot/os/posix/signals_posix.cpp

@@ -1505,6 +1505,14 @@ bool PosixSignals::is_sig_ignored(int sig) {
   }
 }
 
+void* PosixSignals::get_signal_handler_for_signal(int sig) {
+  struct sigaction oact;
+  if (sigaction(sig, (struct sigaction*)nullptr, &oact) == -1) {
+    return nullptr;
+  }
+  return get_signal_handler(&oact);
+}
+
 static void signal_sets_init() {
   sigemptyset(&preinstalled_sigs);
 

src/hotspot/os/posix/signals_posix.hpp

@@ -52,6 +52,8 @@ class PosixSignals : public AllStatic {
 
   static bool is_sig_ignored(int sig);
 
+  static void* get_signal_handler_for_signal(int sig);
+
   static void hotspot_sigmask(Thread* thread);
 
   static void print_signal_handler(outputStream* st, int sig, char* buf, size_t buflen);

src/hotspot/share/jfr/jfr.inline.hpp

@@ -32,7 +32,8 @@
 
 inline bool Jfr::has_sample_request(JavaThread* jt) {
   assert(jt != nullptr, "invariant");
-  return jt->jfr_thread_local()->has_sample_request();
+  JfrThreadLocal* tl = jt->jfr_thread_local();
+  return tl->has_sample_request() || tl->has_cpu_time_jfr_requests();
 }
 
 inline void Jfr::check_and_process_sample_request(JavaThread* jt) {

src/hotspot/share/jfr/jni/jfrJniMethod.cpp

@@ -24,6 +24,7 @@
 
 #include "jfr/jfr.hpp"
 #include "jfr/jfrEvents.hpp"
+#include "jfr/periodic/sampling/jfrCPUTimeThreadSampler.hpp"
 #include "jfr/periodic/sampling/jfrThreadSampler.hpp"
 #include "jfr/recorder/jfrEventSetting.hpp"
 #include "jfr/recorder/jfrRecorder.hpp"
@@ -169,6 +170,11 @@ NO_TRANSITION(jboolean, jfr_set_throttle(JNIEnv* env, jclass jvm, jlong event_ty
   return JNI_TRUE;
 NO_TRANSITION_END
 
+JVM_ENTRY_NO_ENV(void, jfr_set_cpu_throttle(JNIEnv* env, jclass jvm, jdouble rate, jboolean auto_adapt))
+  JfrEventSetting::set_enabled(JfrCPUTimeSampleEvent, rate > 0);
+  JfrCPUTimeThreadSampling::set_rate(rate, auto_adapt == JNI_TRUE);
+JVM_END
+
 NO_TRANSITION(void, jfr_set_miscellaneous(JNIEnv* env, jclass jvm, jlong event_type_id, jlong value))
   JfrEventSetting::set_miscellaneous(event_type_id, value);
   const JfrEventId typed_event_id = (JfrEventId)event_type_id;

src/hotspot/share/jfr/jni/jfrJniMethod.hpp

@@ -129,6 +129,8 @@ jlong JNICALL jfr_get_unloaded_event_classes_count(JNIEnv* env, jclass jvm);
 
 jboolean JNICALL jfr_set_throttle(JNIEnv* env, jclass jvm, jlong event_type_id, jlong event_sample_size, jlong period_ms);
 
+void JNICALL jfr_set_cpu_throttle(JNIEnv* env, jclass jvm, jdouble rate, jboolean auto_adapt);
+
 void JNICALL jfr_set_miscellaneous(JNIEnv* env, jclass jvm, jlong id, jlong value);
 
 void JNICALL jfr_emit_old_object_samples(JNIEnv* env, jclass jvm, jlong cutoff_ticks, jboolean, jboolean);

src/hotspot/share/jfr/jni/jfrJniMethodRegistration.cpp

@@ -83,6 +83,7 @@ JfrJniMethodRegistration::JfrJniMethodRegistration(JNIEnv* env) {
       (char*)"getUnloadedEventClassCount", (char*)"()J", (void*)jfr_get_unloaded_event_classes_count,
       (char*)"setMiscellaneous", (char*)"(JJ)V", (void*)jfr_set_miscellaneous,
       (char*)"setThrottle", (char*)"(JJJ)Z", (void*)jfr_set_throttle,
+      (char*)"setCPUThrottle", (char*)"(DZ)V", (void*)jfr_set_cpu_throttle,
       (char*)"emitOldObjectSamples", (char*)"(JZZ)V", (void*)jfr_emit_old_object_samples,
       (char*)"shouldRotateDisk", (char*)"()Z", (void*)jfr_should_rotate_disk,
       (char*)"exclude", (char*)"(Ljava/lang/Thread;)V", (void*)jfr_exclude_thread,

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

@@ -962,6 +962,22 @@
     <Field type="ThreadState" name="state" label="Thread State" />
   </Event>
 
+  <Event name="CPUTimeSample" category="Java Virtual Machine, Profiling" label="CPU Time Method Sample"
+    description="Snapshot of a threads state from the CPU time sampler. The throttle can be either an upper bound for the event emission rate, e.g. 100/s, or the cpu-time period, e.g. 10ms, with s, ms, us and ns supported as time units."
+    throttle="true" thread="false" experimental="true" startTime="false">
+    <Field type="StackTrace" name="stackTrace" label="Stack Trace" />
+    <Field type="Thread" name="eventThread" label="Thread" />
+    <Field type="boolean" name="failed" label="Failed" description="Failed to obtain the stack trace" />
+    <Field type="Tickspan" name="samplingPeriod" label="CPU Time Sampling Period"/>
+    <Field type="boolean" name="biased" label="Biased" description="The sample is safepoint-biased" />
+  </Event>
+
+  <Event name="CPUTimeSamplesLost" category="Java Virtual Machine, Profiling" label="CPU Time Method Profiling Lost Samples" description="Records that the CPU time sampler lost samples"
+    thread="false" stackTrace="false" startTime="false" experimental="true">
+    <Field type="int" name="lostSamples" label="Lost Samples" />
+    <Field type="Thread" name="eventThread" label="Thread" />
+  </Event>
+
   <Event name="ThreadDump" category="Java Virtual Machine, Runtime" label="Thread Dump" period="everyChunk">
     <Field type="string" name="result" label="Thread Dump" />
   </Event>