/*

 * Copyright 1999-2007 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

inline HeapWord* ThreadLocalAllocBuffer::allocate(size_t size) {

  invariants();

  HeapWord* obj = top();

  if (pointer_delta(end(), obj) >= size) {

    // successful thread-local allocation

    DEBUG_ONLY(Copy::fill_to_words(obj, size, badHeapWordVal));

    // This addition is safe because we know that top is

    // at least size below end, so the add can't wrap.

    set_top(obj + size);

    invariants();

    return obj;

  }

  return NULL;

}

inline size_t ThreadLocalAllocBuffer::compute_size(size_t obj_size) {

  const size_t aligned_obj_size = align_object_size(obj_size);

  // Compute the size for the new TLAB.

  // The "last" tlab may be smaller to reduce fragmentation.

  // unsafe_max_tlab_alloc is just a hint.

  const size_t available_size = Universe::heap()->unsafe_max_tlab_alloc(myThread()) /

                                                  HeapWordSize;

  size_t new_tlab_size = MIN2(available_size, desired_size() + aligned_obj_size);

  // Make sure there's enough room for object and filler int[].

  const size_t obj_plus_filler_size = aligned_obj_size + alignment_reserve();

  if (new_tlab_size < obj_plus_filler_size) {

    // If there isn't enough room for the allocation, return failure.

    if (PrintTLAB && Verbose) {

      gclog_or_tty->print_cr("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ")"

                    " returns failure",

                    obj_size);

    }

    return 0;

  }

  if (PrintTLAB && Verbose) {

    gclog_or_tty->print_cr("ThreadLocalAllocBuffer::compute_size(" SIZE_FORMAT ")"

                  " returns " SIZE_FORMAT,

                  obj_size, new_tlab_size);

  }

  return new_tlab_size;

}

void ThreadLocalAllocBuffer::record_slow_allocation(size_t obj_size) {

  // Raise size required to bypass TLAB next time. Why? Else there's

  // a risk that a thread that repeatedly allocates objects of one

  // size will get stuck on this slow path.

  set_refill_waste_limit(refill_waste_limit() + refill_waste_limit_increment());

  _slow_allocations++;

  if (PrintTLAB && Verbose) {

    Thread* thrd = myThread();

    gclog_or_tty->print("TLAB: %s thread: "INTPTR_FORMAT" [id: %2d]"

                        " obj: "SIZE_FORMAT

                        " free: "SIZE_FORMAT

                        " waste: "SIZE_FORMAT"\n",

                        "slow", thrd, thrd->osthread()->thread_id(),

                        obj_size, free(), refill_waste_limit());

  }

}