src/share/vm/gc_implementation/g1/g1CollectedHeap.inline.hpp

rev 7471 : 8060025: Object copy time regressions after JDK-8031323 and JDK-8057536
Summary: Evaluate and improve object copy time by micro-optimizations and splitting out slow and fast paths aggressively.
Reviewed-by:
Contributed-by: Tony Printezis <tprintezis@twitter.com>, Thomas Schatzl <thomas.schatzl@oracle.com>
rev 7472 : [mq]: 8060025-mikael-review1

*** 33,42 ****
--- 33,77 ----
  #include "gc_implementation/g1/heapRegionManager.inline.hpp"
  #include "gc_implementation/g1/heapRegionSet.inline.hpp"
  #include "runtime/orderAccess.inline.hpp"
  #include "utilities/taskqueue.hpp"
  
+ PLABStats* G1CollectedHeap::alloc_buffer_stats(in_cset_state_t dest) {
+   switch (dest) {
+     case InCSetState::Young:
+       return &_survivor_plab_stats;
+     case InCSetState::Old:
+       return &_old_plab_stats;
+     default:
+       ShouldNotReachHere();
+       return NULL; // Keep some compilers happy
+   }
+ }
+ 
+ size_t G1CollectedHeap::desired_plab_sz(in_cset_state_t dest) {
+   size_t gclab_word_size = alloc_buffer_stats(dest)->desired_plab_sz();
+   // Prevent humongous PLAB sizes for two reasons:
+   // * PLABs are allocated using a similar paths as oops, but should
+   //   never be in a humongous region
+   // * Allowing humongous PLABs needlessly churns the region free lists
+   return MIN2(_humongous_object_threshold_in_words, gclab_word_size);
+ }
+ 
+ HeapWord* G1CollectedHeap::par_allocate_during_gc(in_cset_state_t dest,
+                                                   size_t word_size,
+                                                   AllocationContext_t context) {
+   switch (dest) {
+     case InCSetState::Young:
+       return survivor_attempt_allocation(word_size, context);
+     case InCSetState::Old:
+       return old_attempt_allocation(word_size, context);
+     default:
+       ShouldNotReachHere();
+       return NULL; // Keep some compilers happy
+   }
+ }
+ 
  // Inline functions for G1CollectedHeap
  
  inline AllocationContextStats& G1CollectedHeap::allocation_context_stats() {
    return _allocation_context_stats;
  }