hphp/runtime/vm/treadmill.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present 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 #pragma once
  18
  19 #include <stdint.h>
  20 #include <memory>
  21
  22 namespace HPHP { namespace Treadmill {
  23
  24 //////////////////////////////////////////////////////////////////////
  25
  26 /*
  27  * List of potentiall users of the treadmill, useful for debugging halts
  28  */
  29 enum class SessionKind {
  30   None,
  31   DebuggerClient,
  32   PreloadRepo,
  33   Watchman,
  34   Vsdebug,
  35   FactsWorker,
  36   CLIServer,
  37   AdminPort,
  38   HttpRequest,
  39   RpcRequest,
  40   TranslateWorker,
  41   Retranslate,
  42   RetranslateAll,
  43   ProfData,
  44   UnitTests,
  45   CompileRepo,
  46   HHBBC,
  47   CompilerEmit,
  48   CompilerAnalysis,
  49   CLISession,
  50   UnitReaper
  51 };
  52
  53 /*
  54  * An invalid request index.
  55  */
  56 constexpr int64_t kInvalidRequestIdx = -1;
  57 /*
  58  * Return the current thread's index.
  59  */
  60 int64_t requestIdx();
  61
  62 /*
  63  * The Treadmill allows us to defer work until all currently
  64  * outstanding requests have finished.  We hook request start and
  65  * finish to know when these events happen.
  66  */
  67 void startRequest(SessionKind session_kind);
  68 void finishRequest();
  69
  70 /*
  71  * Returns the unique GenCount identifying the oldest request in
  72  * flight (or zero if there is none).
  73  */
  74 int64_t getOldestRequestGenCount();
  75
  76 /*
  77  * Returns the oldest start time in seconds of all requests in flight.
  78  * If there are no requests in flight the return value is 0.
  79  * The value returned should be used as a conservative and true value
  80  * for the oldest start time of any request in flight. In that sense
  81  * the value is safe to compare against in a less-than relationship.
  82  */
  83 int64_t getOldestStartTime();
  84
  85 /*
  86  * Returns for how long (wall time) the oldest request in flight has
  87  * been running, in seconds.
  88  */
  89 int64_t getAgeOldestRequest();
  90
  91 /*
  92  * Returns the unique GenCount identifying this request.
  93  */
  94 int64_t getRequestGenCount();
  95
  96 /*
  97  * Ask for memory to be freed (as in free, not delete) by the next
  98  * appropriate treadmill round.
  99  */
 100 void deferredFree(void*);
 101
 102 /*
 103  * Used to get debug information about the treadmill.
 104  */
 105 std::string dumpTreadmillInfo();
 106
 107 /*
 108  * Schedule a function to run on the next appropriate treadmill round.
 109  *
 110  * The function will be called from the base mutex rank.
 111  *
 112  * Note: the function passed here escapes (naturally).  If you use a
 113  * lambda here, copy things into the lambda by value.
 114  *
 115  * Important: f() must not throw an exception.
 116  */
 117 template<class F> void enqueue(F&& f);
 118
 119 struct Session final {
 120   Session(SessionKind session_kind) { startRequest(session_kind); }
 121   ~Session() { finishRequest(); }
 122   Session(Session&&) = delete;
 123   Session& operator=(Session&&) = delete;
 124 };
 125
 126 //////////////////////////////////////////////////////////////////////
 127
 128 }}
 129
 130 #include "hphp/runtime/vm/treadmill-inl.h"