RFR: Add JFR parallel and concurrent events

[Aleksey Shipilev]

On 10/10/2018 09:25 PM, Zhengyu Gu wrote:
> The patch adds JFR parallel and concurrent events for Shenandoah.
> 
> It also reshuffles a few includes and moves ShenandoahWorkerTimingsTracker and
> ShenandoahTerminationTracker to separate files, to avoid recursive inclusion.
> 
> 
> Webrev: http://cr.openjdk.java.net/~zgu/shenandoah/jfr_conc_par_events/webrev.00/index.html

Looks good.

Nits:

*) Excess newline in shenandoahUtils.cpp:

 144


*) I think we can use switch here:

 119 bool ShenandoahGCPhase::is_root_work_phase() {
 120   ShenandoahPhaseTimings::Phase phase = current_phase();
 121   return phase == ShenandoahPhaseTimings::scan_roots ||
 122          phase == ShenandoahPhaseTimings::update_roots ||
 123          phase == ShenandoahPhaseTimings::init_evac ||
 124          phase == ShenandoahPhaseTimings::final_update_refs_roots ||
 125          phase == ShenandoahPhaseTimings::degen_gc_update_roots ||
 126          phase == ShenandoahPhaseTimings::init_traversal_gc_work ||
 127          phase == ShenandoahPhaseTimings::final_traversal_gc_work ||
 128          phase == ShenandoahPhaseTimings::final_traversal_update_roots ||
 129          phase == ShenandoahPhaseTimings::full_gc_roots;
 130 }

*) No need for local variable "current" here?

 166 ShenandoahConcurrentWorkerSession::~ShenandoahConcurrentWorkerSession() {
 167   ShenandoahPhaseTimings::Phase current = ShenandoahGCPhase::current_phase();
 168   _event.commit(GCId::current(), ShenandoahPhaseTimings::phase_name(current));
 169 }
 170
 171 ShenandoahParallelWorkerSession::~ShenandoahParallelWorkerSession() {
 172   ShenandoahPhaseTimings::Phase current = ShenandoahGCPhase::current_phase();
 173   _event.commit(GCId::current(), _worker_id, ShenandoahPhaseTimings::phase_name(current));
 174 }

*) Duplicate "protected"?

 121 class ShenandoahWorkerSession : public StackObj {
 122 protected:
 123   uint _worker_id;
 124 protected:
 125   ShenandoahWorkerSession(uint worker_id);


Thanks,
-Aleksey