hphp/runtime/vm/treadmill.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2014 Facebook, Inc. (http://www.facebook.com)     |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #ifndef incl_HPHP_TREADMILL_H_
  18 #define incl_HPHP_TREADMILL_H_
  19
  20 #include <stdint.h>
  21 #include <memory>
  22
  23 namespace HPHP { namespace Treadmill {
  24
  25 //////////////////////////////////////////////////////////////////////
  26
  27 /*
  28  * The Treadmill allows us to defer work until all currently
  29  * outstanding requests have finished.  We hook request start and
  30  * finish to know when these events happen.
  31  */
  32 void startRequest();
  33 void finishRequest();
  34
  35 /*
  36  * Returns the oldest start time in seconds of all requests in flight.
  37  * If there are no requests in flight the return value is 0.
  38  * The value returned should be used as a conservative and true value
  39  * for the oldest start time of any request in flight. In that sense
  40  * the value is safe to compare against in a less-than relationship.
  41  */
  42 int64_t getOldestStartTime();
  43
  44 /*
  45  * Ask for memory to be freed (as in free, not delete) by the next
  46  * appropriate treadmill round.
  47  */
  48 void deferredFree(void*);
  49
  50 /*
  51  * Schedule a function to run on the next appropriate treadmill round.
  52  *
  53  * The function will be called from the base mutex rank.
  54  *
  55  * Note: the function passed here escapes (naturally).  If you use a
  56  * lambda here, copy things into the lambda by value.
  57  *
  58  * Important: f() must not throw an exception.
  59  */
  60 template<class F> void enqueue(F&& f);
  61
  62 //////////////////////////////////////////////////////////////////////
  63
  64 }}
  65
  66 #include "hphp/runtime/vm/treadmill-inl.h"
  67
  68 #endif