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

/*
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#include "gc/shared/gc_globals.hpp"
#include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
#include "gc/shenandoah/shenandoahController.hpp"
#include "gc/shenandoah/shenandoahHeap.hpp"
#include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"

void ShenandoahController::pacing_notify_alloc(size_t words) {
  assert(ShenandoahPacing, "should only call when pacing is enabled");
  Atomic::add(&_allocs_seen, words, memory_order_relaxed);
}

size_t ShenandoahController::reset_allocs_seen() {
  return Atomic::xchg(&_allocs_seen, (size_t)0, memory_order_relaxed);
}

void ShenandoahController::update_gc_id() {
  Atomic::inc(&_gc_id);
}

size_t ShenandoahController::get_gc_id() {
  return Atomic::load(&_gc_id);
}

void ShenandoahController::handle_alloc_failure(const ShenandoahAllocRequest& req, bool block) {
  assert(current()->is_Java_thread(), "expect Java thread here");

  const bool is_humongous = ShenandoahHeapRegion::requires_humongous(req.size());
  const GCCause::Cause cause = is_humongous ? GCCause::_shenandoah_humongous_allocation_failure : GCCause::_allocation_failure;

  ShenandoahHeap* const heap = ShenandoahHeap::heap();
  if (heap->cancel_gc(cause)) {
    log_info(gc)("Failed to allocate %s, " PROPERFMT, req.type_string(), PROPERFMTARGS(req.size() * HeapWordSize));
    request_gc(cause);
  }

  if (block) {
    MonitorLocker ml(&_alloc_failure_waiters_lock);
    while (!should_terminate() && ShenandoahCollectorPolicy::is_allocation_failure(heap->cancelled_cause())) {
      ml.wait();
    }
  }
}

void ShenandoahController::handle_alloc_failure_evac(size_t words) {

  ShenandoahHeap* const heap = ShenandoahHeap::heap();
  const bool is_humongous = ShenandoahHeapRegion::requires_humongous(words);
  const GCCause::Cause cause = is_humongous ? GCCause::_shenandoah_humongous_allocation_failure : GCCause::_shenandoah_allocation_failure_evac;

  if (heap->cancel_gc(cause)) {
    log_info(gc)("Failed to allocate " PROPERFMT " for evacuation", PROPERFMTARGS(words * HeapWordSize));
  }
}

void ShenandoahController::notify_alloc_failure_waiters() {
  MonitorLocker ml(&_alloc_failure_waiters_lock);
  ml.notify_all();
}