15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Copyright (c) 2009, Google Inc.
25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * All rights reserved.
35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *
45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * Redistribution and use in source and binary forms, with or without
55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * modification, are permitted provided that the following conditions are
65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * met:
75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *
85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *     * Redistributions of source code must retain the above copyright
95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * notice, this list of conditions and the following disclaimer.
105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *     * Redistributions in binary form must reproduce the above
115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * copyright notice, this list of conditions and the following disclaimer
125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * in the documentation and/or other materials provided with the
135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * distribution.
145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *     * Neither the name of Google Inc. nor the names of its
155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * contributors may be used to endorse or promote products derived from
165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * this software without specific prior written permission.
175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *
185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *
305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * ---
315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * This file is a Posix-specific part of spinlock_internal.cc
325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */
335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <config.h>
355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <errno.h>
365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifdef HAVE_SCHED_H
375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <sched.h>      /* For sched_yield() */
385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif
395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <time.h>       /* For nanosleep() */
405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace base {
425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace internal {
435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void SpinLockDelay(volatile Atomic32 *w, int32 value, int loop) {
455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  int save_errno = errno;
465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  if (loop == 0) {
475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  } else if (loop == 1) {
485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)    sched_yield();
495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  } else {
505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)    struct timespec tm;
515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)    tm.tv_sec = 0;
525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)    tm.tv_nsec = base::internal::SuggestedDelayNS(loop);
535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)    nanosleep(&tm, NULL);
545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  }
555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)  errno = save_errno;
565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}
575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void SpinLockWake(volatile Atomic32 *w, bool all) {
595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}
605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)
615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace internal
625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace base
63