15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)/* Copyright (c) 2010, 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 an internal part spinlock.cc and once.cc 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) * It may not be used directly by code outside of //base. 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) */ 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifndef BASE_SPINLOCK_INTERNAL_H_ 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define BASE_SPINLOCK_INTERNAL_H_ 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <config.h> 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/basictypes.h" 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/atomicops.h" 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace base { 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace internal { 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// SpinLockWait() waits until it can perform one of several transitions from 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// "from" to "to". It returns when it performs a transition where done==true. 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)struct SpinLockWaitTransition { 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int32 from; 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int32 to; 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) bool done; 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Wait until *w can transition from trans[i].from to trans[i].to for some i 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// satisfying 0<=i<n && trans[i].done, atomically make the transition, 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// then return the old value of *w. Make any other atomic tranistions 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// where !trans[i].done, but continue waiting. 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)int32 SpinLockWait(volatile Atomic32 *w, int n, 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const SpinLockWaitTransition trans[]); 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void SpinLockWake(volatile Atomic32 *w, bool all); 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void SpinLockDelay(volatile Atomic32 *w, int32 value, int loop); 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace internal 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace base 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif 65