8327365: Inline and remove GCStats

Reviewed-by: gli, tschatzl

src/hotspot/share/gc/parallel/psAdaptiveSizePolicy.cpp

@@ -49,7 +49,7 @@ PSAdaptiveSizePolicy::PSAdaptiveSizePolicy(size_t init_eden_size,
                         gc_cost_ratio),
      _avg_major_pause(new AdaptivePaddedAverage(AdaptiveTimeWeight, PausePadding)),
      _avg_base_footprint(new AdaptiveWeightedAverage(AdaptiveSizePolicyWeight)),
-     _gc_stats(),
+     _avg_promoted(new AdaptivePaddedNoZeroDevAverage(AdaptiveSizePolicyWeight, PromotedPadding)),
      _major_pause_old_estimator(new LinearLeastSquareFit(AdaptiveSizePolicyWeight)),
      _major_pause_young_estimator(new LinearLeastSquareFit(AdaptiveSizePolicyWeight)),
      _latest_major_mutator_interval_seconds(0),

src/hotspot/share/gc/parallel/psAdaptiveSizePolicy.hpp

@@ -27,7 +27,6 @@
 
 #include "gc/shared/adaptiveSizePolicy.hpp"
 #include "gc/shared/gcCause.hpp"
-#include "gc/shared/gcStats.hpp"
 #include "gc/shared/gcUtil.hpp"
 #include "utilities/align.hpp"
 
@@ -72,8 +71,8 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
   // Footprint statistics
   AdaptiveWeightedAverage* _avg_base_footprint;
 
-  // Statistical data gathered for GC
+  // Statistics for promoted objs
-  GCStats _gc_stats;
+  AdaptivePaddedNoZeroDevAverage*   _avg_promoted;
 
   // Variable for estimating the major and minor pause times.
   // These variables represent linear least-squares fits of
@@ -166,7 +165,7 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
  public:
   // Accessors for use by performance counters
   AdaptivePaddedNoZeroDevAverage*  avg_promoted() const {
-    return _gc_stats.avg_promoted();
+    return _avg_promoted;
   }
   AdaptiveWeightedAverage* avg_base_footprint() const {
     return _avg_base_footprint;

src/hotspot/share/gc/serial/generation.hpp

@@ -51,9 +51,7 @@
 class DefNewGeneration;
 class GCMemoryManager;
 class ContiguousSpace;
-
 class OopClosure;
-class GCStats;
 
 class Generation: public CHeapObj<mtGC> {
   friend class VMStructs;
@@ -73,9 +71,6 @@ class Generation: public CHeapObj<mtGC> {
   // Performance Counters
   CollectorCounters* _gc_counters;
 
-  // Statistics for garbage collection
-  GCStats* _gc_stats;
-
   // Initialize the generation.
   Generation(ReservedSpace rs, size_t initial_byte_size);
 
@@ -168,15 +163,6 @@ class Generation: public CHeapObj<mtGC> {
   // still unsuccessful, return "null".
   virtual HeapWord* expand_and_allocate(size_t word_size, bool is_tlab) = 0;
 
-  // Generations may keep statistics about collection. This method
-  // updates those statistics. current_generation is the generation
-  // that was most recently collected. This allows the generation to
-  // decide what statistics are valid to collect. For example, the
-  // generation can decide to gather the amount of promoted data if
-  // the collection of the young generation has completed.
-  GCStats* gc_stats() const { return _gc_stats; }
-  virtual void update_gc_stats(Generation* current_generation, bool full) {}
-
   // Printing
   virtual const char* name() const = 0;
   virtual const char* short_name() const = 0;

src/hotspot/share/gc/serial/tenuredGeneration.cpp

@@ -308,7 +308,7 @@ TenuredGeneration::TenuredGeneration(ReservedSpace rs,
   _shrink_factor = ShrinkHeapInSteps ? 0 : 100;
   _capacity_at_prologue = 0;
 
-  _gc_stats = new GCStats();
+  _avg_promoted = new AdaptivePaddedNoZeroDevAverage(AdaptiveSizePolicyWeight, PromotedPadding);
 
   // initialize performance counters
 
@@ -390,7 +390,7 @@ void TenuredGeneration::update_gc_stats(Generation* current_generation,
     // also possible that no promotion was needed.
     if (used_before_gc >= _used_at_prologue) {
       size_t promoted_in_bytes = used_before_gc - _used_at_prologue;
-      gc_stats()->avg_promoted()->sample(promoted_in_bytes);
+      _avg_promoted->sample(promoted_in_bytes);
     }
   }
 }
@@ -404,7 +404,7 @@ void TenuredGeneration::update_counters() {
 
 bool TenuredGeneration::promotion_attempt_is_safe(size_t max_promotion_in_bytes) const {
   size_t available = max_contiguous_available();
-  size_t av_promo  = (size_t)gc_stats()->avg_promoted()->padded_average();
+  size_t av_promo  = (size_t)_avg_promoted->padded_average();
   bool   res = (available >= av_promo) || (available >= max_promotion_in_bytes);
 
   log_trace(gc)("Tenured: promo attempt is%s safe: available(" SIZE_FORMAT ") %s av_promo(" SIZE_FORMAT "), max_promo(" SIZE_FORMAT ")",

src/hotspot/share/gc/serial/tenuredGeneration.hpp

@@ -27,7 +27,6 @@
 
 #include "gc/serial/cSpaceCounters.hpp"
 #include "gc/serial/generation.hpp"
-#include "gc/shared/gcStats.hpp"
 #include "gc/shared/generationCounters.hpp"
 #include "gc/shared/space.hpp"
 #include "utilities/macros.hpp"
@@ -71,6 +70,10 @@ class TenuredGeneration: public Generation {
   GenerationCounters* _gen_counters;
   CSpaceCounters*     _space_counters;
 
+  // Avg amount promoted; used for avoiding promotion undo
+  // This class does not update deviations if the sample is zero.
+  AdaptivePaddedNoZeroDevAverage*   _avg_promoted;
+
   // Attempt to expand the generation by "bytes".  Expand by at a
   // minimum "expand_bytes".  Return true if some amount (not
   // necessarily the full "bytes") was done.
@@ -80,7 +83,8 @@ class TenuredGeneration: public Generation {
   void shrink(size_t bytes);
 
   void compute_new_size_inner();
- public:
+
+public:
   void compute_new_size();
 
   TenuredSpace* space() const { return _the_space; }
@@ -158,7 +162,7 @@ class TenuredGeneration: public Generation {
 
   // Statistics
 
-  virtual void update_gc_stats(Generation* current_generation, bool full);
+  void update_gc_stats(Generation* current_generation, bool full);
 
   // Returns true if promotions of the specified amount are
   // likely to succeed without a promotion failure.

src/hotspot/share/gc/shared/gcStats.cpp

@@ -1,30 +0,0 @@
-/*
- * Copyright (c) 2003, 2021, 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.
- *
- */
-
-#include "precompiled.hpp"
-#include "gc/shared/gcStats.hpp"
-#include "gc/shared/gcUtil.hpp"
-#include "gc/shared/gc_globals.hpp"
-
-GCStats::GCStats() : _avg_promoted(new AdaptivePaddedNoZeroDevAverage(AdaptiveSizePolicyWeight, PromotedPadding)) {}

src/hotspot/share/gc/shared/gcStats.hpp

@@ -1,42 +0,0 @@
-/*
- * Copyright (c) 2003, 2019, 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.
- *
- */
-
-#ifndef SHARE_GC_SHARED_GCSTATS_HPP
-#define SHARE_GC_SHARED_GCSTATS_HPP
-
-#include "gc/shared/gcUtil.hpp"
-
-class GCStats : public CHeapObj<mtGC> {
- protected:
-  // Avg amount promoted; used for avoiding promotion undo
-  // This class does not update deviations if the sample is zero.
-  AdaptivePaddedNoZeroDevAverage*   _avg_promoted;
-
- public:
-  GCStats();
-
-  AdaptivePaddedNoZeroDevAverage*  avg_promoted() const { return _avg_promoted; }
-};
-
-#endif // SHARE_GC_SHARED_GCSTATS_HPP