ceph/src/mds/LocalLockC.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 LocalLockC : public SimpleLock {
  22 public:
  23   LocalLockC(MDSCacheObject *o, LockType *t) :
  24     SimpleLock(o, t) {
  25     set_state(LOCK_LOCK); // always.
  26   }
  27
  28   bool is_locallock() const override {
  29     return true;
  30   }
  31
  32   bool can_xlock_local() const {
  33     return !is_wrlocked() && (get_xlock_by() == MutationRef());
  34   }
  35
  36   bool can_wrlock() const {
  37     return !is_xlocked();
  38   }
  39   void get_wrlock(client_t client) {
  40     ceph_assert(can_wrlock());
  41     SimpleLock::get_wrlock();
  42     last_wrlock_client = client;
  43   }
  44   void put_wrlock() {
  45     SimpleLock::put_wrlock();
  46     if (get_num_wrlocks() == 0)
  47       last_wrlock_client = client_t();
  48   }
  49   client_t get_last_wrlock_client() const {
  50     return last_wrlock_client;
  51   }
  52
  53   void print(std::ostream& out) const override {
  54     out << "(";
  55     _print(out);
  56     if (last_wrlock_client >= 0)
  57       out << " last_client=" << last_wrlock_client;
  58     out << ")";
  59   }
  60
  61 private:
  62   client_t last_wrlock_client;
  63 };
  64 #endif