src/hotspot/share/gc/shenandoah/shenandoahMemoryPool.cpp

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#include "gc/shenandoah/shenandoahMemoryPool.hpp"
#include "gc/shenandoah/shenandoahOldGeneration.hpp"
#include "gc/shenandoah/shenandoahYoungGeneration.hpp"

ShenandoahMemoryPool::ShenandoahMemoryPool(ShenandoahHeap* heap,
                                           const char* name) :
        CollectedMemoryPool(name,
                            heap->initial_capacity(),
                            heap->max_capacity(),
                            true /* support_usage_threshold */),
                            _heap(heap) {}

ShenandoahMemoryPool::ShenandoahMemoryPool(ShenandoahHeap* heap,
                                           const char* name,
                                           size_t initial_capacity,
                                           size_t max_capacity) :
        CollectedMemoryPool(name,
                            initial_capacity,
                            max_capacity,
                            true /* support_usage_threshold */),
                            _heap(heap) {}


MemoryUsage ShenandoahMemoryPool::get_memory_usage() {
  size_t initial   = initial_size();
  size_t max       = max_size();
  size_t used      = used_in_bytes();
  size_t committed = _heap->committed();

  // These asserts can never fail: max is stable, and all updates to other values never overflow max.
  assert(initial <= max,    "initial: %zu, max: %zu",   initial,   max);
  assert(used <= max,       "used: %zu, max: %zu",      used,      max);
  assert(committed <= max,  "committed: %zu, max: %zu", committed, max);

  // Committed and used are updated concurrently and independently. They can momentarily break
  // the assert below, which would also fail in downstream code. To avoid that, adjust values
  // to make sense under the race. See JDK-8207200.
  committed = MAX2(used, committed);
  assert(used <= committed, "used: %zu, committed: %zu", used,      committed);

  return MemoryUsage(initial, used, committed, max);
}

size_t ShenandoahMemoryPool::used_in_bytes() {
  return _heap->used();
}

size_t ShenandoahMemoryPool::max_size() const {
  return _heap->max_capacity();
}

ShenandoahGenerationalMemoryPool::ShenandoahGenerationalMemoryPool(ShenandoahHeap* heap, const char* name,
                                                                   ShenandoahGeneration* generation) :
        ShenandoahMemoryPool(heap, name, 0, heap->max_capacity()),
        _generation(generation) { }

MemoryUsage ShenandoahGenerationalMemoryPool::get_memory_usage() {
  size_t initial   = initial_size();
  size_t max       = max_size();
  size_t used      = used_in_bytes();
  size_t committed = _generation->used_regions_size();

  return MemoryUsage(initial, used, committed, max);
}

size_t ShenandoahGenerationalMemoryPool::used_in_bytes() {
  return _generation->used();
}

ShenandoahYoungGenMemoryPool::ShenandoahYoungGenMemoryPool(ShenandoahHeap* heap) :
        ShenandoahGenerationalMemoryPool(heap,
                             "Shenandoah Young Gen",
                             heap->young_generation()) { }

ShenandoahOldGenMemoryPool::ShenandoahOldGenMemoryPool(ShenandoahHeap* heap) :
        ShenandoahGenerationalMemoryPool(heap,
                             "Shenandoah Old Gen",
                             heap->old_generation()) { }