src/share/vm/memory/genCollectedHeap.hpp

rev 8333 : 8077842: Remove the level parameter passed around in GenCollectedHeap
Reviewed-by:

@@ -92,37 +92,37 @@
                                bool   is_tlab,
                                bool   first_only);
 
   // Helper function for two callbacks below.
   // Considers collection of the first max_level+1 generations.
-  void do_collection(bool   full,
-                     bool   clear_all_soft_refs,
-                     size_t size,
-                     bool   is_tlab,
-                     int    max_level);
+  void do_collection(bool             full,
+                     bool             clear_all_soft_refs,
+                     size_t           size,
+                     bool             is_tlab,
+                     Generation::Type max_generation);
 
   // Callback from VM_GenCollectForAllocation operation.
   // This function does everything necessary/possible to satisfy an
   // allocation request that failed in the youngest generation that should
   // have handled it (including collection, expansion, etc.)
   HeapWord* satisfy_failed_allocation(size_t size, bool is_tlab);
 
   // Callback from VM_GenCollectFull operation.
   // Perform a full collection of the first max_level+1 generations.
   virtual void do_full_collection(bool clear_all_soft_refs);
-  void do_full_collection(bool clear_all_soft_refs, int max_level);
+  void do_full_collection(bool clear_all_soft_refs, Generation::Type max_generation);
 
   // Does the "cause" of GC indicate that
   // we absolutely __must__ clear soft refs?
   bool must_clear_all_soft_refs();
 
 public:
   GenCollectedHeap(GenCollectorPolicy *policy);
 
   FlexibleWorkGang* workers() const { return _workers; }
 
-  GCStats* gc_stats(int level) const;
+  GCStats* gc_stats(Generation* generation) const;
 
   // Returns JNI_OK on success
   virtual jint initialize();
 
   // Reserve aligned space for the heap as needed by the contained generations.

@@ -157,12 +157,12 @@
   }
 
   size_t capacity() const;
   size_t used() const;
 
-  // Save the "used_region" for generations level and lower.
-  void save_used_regions(int level);
+  // Save the "used_region" for both generations.
+  void save_used_regions();
 
   size_t max_capacity() const;
 
   HeapWord* mem_allocate(size_t size,
                          bool*  gc_overhead_limit_was_exceeded);

@@ -179,13 +179,13 @@
   void collect(GCCause::Cause cause);
 
   // The same as above but assume that the caller holds the Heap_lock.
   void collect_locked(GCCause::Cause cause);
 
-  // Perform a full collection of the first max_level+1 generations.
+  // Perform a full collection of generations up to and including max_generation.
   // Mostly used for testing purposes. Caller does not hold the Heap_lock on entry.
-  void collect(GCCause::Cause cause, int max_level);
+  void collect(GCCause::Cause cause, Generation::Type max_generation);
 
   // Returns "TRUE" iff "p" points into the committed areas of the heap.
   // The methods is_in(), is_in_closed_subset() and is_in_youngest() may
   // be expensive to compute in general, so, to prevent
   // their inadvertent use in product jvm's, we restrict their use to

@@ -311,14 +311,12 @@
     _young_gen->update_time_of_last_gc(now);
     _old_gen->update_time_of_last_gc(now);
   }
 
   // Update the gc statistics for each generation.
-  // "level" is the level of the latest collection.
-  void update_gc_stats(int current_level, bool full) {
-    _young_gen->update_gc_stats(current_level, full);
-    _old_gen->update_gc_stats(current_level, full);
+  void update_gc_stats(Generation* current_generation, bool full) {
+    _old_gen->update_gc_stats(current_generation, full);
   }
 
   bool no_gc_in_progress() { return !is_gc_active(); }
 
   // Override.

@@ -365,12 +363,12 @@
 
   void set_par_threads(uint t);
   void set_n_termination(uint t);
 
   // Invoke the "do_oop" method of one of the closures "not_older_gens"
-  // or "older_gens" on root locations for the generation at
-  // "level".  (The "older_gens" closure is used for scanning references
+  // or "older_gens" on root locations for the generations depending on
+  // the type.  (The "older_gens" closure is used for scanning references
   // from older generations; "not_older_gens" is used everywhere else.)
   // If "younger_gens_as_roots" is false, younger generations are
   // not scanned as roots; in this case, the caller must be arranging to
   // scan the younger generations itself.  (For example, a generation might
   // explicitly mark reachable objects in younger generations, to avoid

@@ -391,11 +389,11 @@
                      OopClosure* weak_roots,
                      CLDClosure* strong_cld_closure,
                      CLDClosure* weak_cld_closure,
                      CodeBlobClosure* code_roots);
 
-  void gen_process_roots(int level,
+  void gen_process_roots(Generation::Type type,
                          bool younger_gens_as_roots,
                          bool activate_scope,
                          ScanningOption so,
                          OopsInGenClosure* not_older_gens,
                          OopsInGenClosure* weak_roots,

@@ -406,11 +404,11 @@
 
  public:
   static const bool StrongAndWeakRoots = false;
   static const bool StrongRootsOnly    = true;
 
-  void gen_process_roots(int level,
+  void gen_process_roots(Generation::Type type,
                          bool younger_gens_as_roots,
                          bool activate_scope,
                          ScanningOption so,
                          bool only_strong_roots,
                          OopsInGenClosure* not_older_gens,

@@ -431,33 +429,29 @@
   // allocated since the last call to save_marks in generations at or above
   // "level".  The "cur" closure is
   // applied to references in the generation at "level", and the "older"
   // closure to older generations.
 #define GCH_SINCE_SAVE_MARKS_ITERATE_DECL(OopClosureType, nv_suffix)    \
-  void oop_since_save_marks_iterate(int level,                          \
+  void oop_since_save_marks_iterate(Generation::Type start_gen,         \
                                     OopClosureType* cur,                \
                                     OopClosureType* older);
 
   ALL_SINCE_SAVE_MARKS_CLOSURES(GCH_SINCE_SAVE_MARKS_ITERATE_DECL)
 
 #undef GCH_SINCE_SAVE_MARKS_ITERATE_DECL
 
-  // Returns "true" iff no allocations have occurred in any generation at
-  // "level" or above since the last
+  // Returns "true" iff no allocations have occurred since the last
   // call to "save_marks".
-  bool no_allocs_since_save_marks(int level);
+  bool no_allocs_since_save_marks(bool include_young);
 
   // Returns true if an incremental collection is likely to fail.
   // We optionally consult the young gen, if asked to do so;
   // otherwise we base our answer on whether the previous incremental
   // collection attempt failed with no corrective action as of yet.
   bool incremental_collection_will_fail(bool consult_young) {
-    // Assumes a 2-generation system; the first disjunct remembers if an
-    // incremental collection failed, even when we thought (second disjunct)
-    // that it would not.
-    assert(heap()->collector_policy()->is_generation_policy(),
-           "the following definition may not be suitable for an n(>2)-generation system");
+    // The first disjunct remembers if an incremental collection failed, even
+    // when we thought (second disjunct) that it would not.
     return incremental_collection_failed() ||
            (consult_young && !_young_gen->collection_attempt_is_safe());
   }
 
   // If a generation bails out of an incremental collection,

@@ -493,14 +487,14 @@
   // For use by mark-sweep.  As implemented, mark-sweep-compact is global
   // in an essential way: compaction is performed across generations, by
   // iterating over spaces.
   void prepare_for_compaction();
 
-  // Perform a full collection of the first max_level+1 generations.
+  // Perform a full collection of the generations up to and including max_generation.
   // This is the low level interface used by the public versions of
   // collect() and collect_locked(). Caller holds the Heap_lock on entry.
-  void collect_locked(GCCause::Cause cause, int max_level);
+  void collect_locked(GCCause::Cause cause, Generation::Type max_generation);
 
   // Returns success or failure.
   bool create_cms_collector();
 
   // In support of ExplicitGCInvokesConcurrent functionality