hotspot/src/share/vm/gc/parallel/psPromotionLAB.inline.hpp
author tschatzl
Thu, 28 Jan 2016 13:30:12 +0100
changeset 35877 a2a62511d0f8
parent 30764 fec48bf5a827
child 46565 8dcbf532ea00
permissions -rw-r--r--
8146987: Improve Parallel GC Full GC by caching results of live_words_in_range() Summary: A large part of time in the parallel scavenge collector is spent finding out the amount of live words within memory ranges to find out where to move an object to. Try to incrementally calculate this value. Reviewed-by: tschatzl, mgerdin, jmasa Contributed-by: ray alex <sky1young@gmail.com>

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#ifndef SHARE_VM_GC_PARALLEL_PSPROMOTIONLAB_INLINE_HPP
#define SHARE_VM_GC_PARALLEL_PSPROMOTIONLAB_INLINE_HPP

#include "gc/parallel/psPromotionLAB.hpp"
#include "gc/shared/collectedHeap.inline.hpp"

HeapWord* PSYoungPromotionLAB::allocate(size_t size) {
  // Can't assert this, when young fills, we keep the LAB around, but flushed.
  // assert(_state != flushed, "Sanity");
  HeapWord* obj = CollectedHeap::align_allocation_or_fail(top(), end(), SurvivorAlignmentInBytes);
  if (obj == NULL) {
    return NULL;
  }

  HeapWord* new_top = obj + size;
  // The 'new_top>obj' check is needed to detect overflow of obj+size.
  if (new_top > obj && new_top <= end()) {
    set_top(new_top);
    assert(is_ptr_aligned(obj, SurvivorAlignmentInBytes) && is_object_aligned((intptr_t)new_top),
           "checking alignment");
    return obj;
  } else {
    set_top(obj);
    return NULL;
  }
}

#endif // SHARE_VM_GC_PARALLEL_PSPROMOTIONLAB_INLINE_HPP