ceph/src/mds/LocalLock.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15
  16 #ifndef CEPH_LOCALLOCK_H
  17 #define CEPH_LOCALLOCK_H
  18
  19 #include "SimpleLock.h"
  20
  21 class LocalLock : public SimpleLock {
  22 public:
  23   client_t last_wrlock_client;
  24
  25   LocalLock(MDSCacheObject *o, LockType *t) :
  26     SimpleLock(o, t) {
  27     set_state(LOCK_LOCK); // always.
  28   }
  29
  30   bool is_locallock() const override {
  31     return true;
  32   }
  33
  34   bool can_xlock_local() const {
  35     return !is_wrlocked() && (get_xlock_by() == MutationRef());
  36   }
  37
  38   bool can_wrlock() const {
  39     return !is_xlocked();
  40   }
  41   void get_wrlock(client_t client) {
  42     assert(can_wrlock());
  43     SimpleLock::get_wrlock();
  44     last_wrlock_client = client;
  45   }
  46   void put_wrlock() {
  47     SimpleLock::put_wrlock();
  48     if (get_num_wrlocks() == 0)
  49       last_wrlock_client = client_t();
  50   }
  51   client_t get_last_wrlock_client() const {
  52     return last_wrlock_client;
  53   }
  54
  55   void print(ostream& out) const override {
  56     out << "(";
  57     _print(out);
  58     if (last_wrlock_client >= 0)
  59       out << " last_client=" << last_wrlock_client;
  60     out << ")";
  61   }
  62 };
  63
  64
  65 #endif