ceph/src/common/ceph_context.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) 2011 New Dream Network
   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 #ifndef CEPH_CEPHCONTEXT_H
  16 #define CEPH_CEPHCONTEXT_H
  17
  18 #include <atomic>
  19 #include <set>
  20 #include <boost/noncopyable.hpp>
  21
  22 #include "common/cmdparse.h"
  23 #include "crush/CrushLocation.h"
  24 #include "include/Spinlock.h"
  25
  26 class AdminSocket;
  27 class CephContextServiceThread;
  28 class PerfCountersCollection;
  29 class PerfCounters;
  30 class md_config_obs_t;
  31 struct md_config_t;
  32 class CephContextHook;
  33 class CephContextObs;
  34 class CryptoHandler;
  35
  36 namespace ceph {
  37   class PluginRegistry;
  38   class HeartbeatMap;
  39   namespace logging {
  40     class Log;
  41   }
  42 }
  43
  44 /* A CephContext represents the context held by a single library user.
  45  * There can be multiple CephContexts in the same process.
  46  *
  47  * For daemons and utility programs, there will be only one CephContext.  The
  48  * CephContext contains the configuration, the dout object, and anything else
  49  * that you might want to pass to libcommon with every function call.
  50  */
  51 class CephContext {
  52 public:
  53   CephContext(uint32_t module_type_, int init_flags_ = 0);
  54
  55   // ref count!
  56 private:
  57   ~CephContext();
  58   std::atomic<unsigned> nref;
  59 public:
  60   CephContext *get() {
  61     ++nref;
  62     return this;
  63   }
  64   void put();
  65
  66   md_config_t *_conf;
  67   ceph::logging::Log *_log;
  68
  69   /* init ceph::crypto */
  70   void init_crypto();
  71
  72   /* Start the Ceph Context's service thread */
  73   void start_service_thread();
  74
  75   /* Reopen the log files */
  76   void reopen_logs();
  77
  78   /* Get the module type (client, mon, osd, mds, etc.) */
  79   uint32_t get_module_type() const;
  80
  81   void set_init_flags(int flags);
  82   int get_init_flags() const;
  83
  84   /* Get the PerfCountersCollection of this CephContext */
  85   PerfCountersCollection *get_perfcounters_collection();
  86
  87   ceph::HeartbeatMap *get_heartbeat_map() {
  88     return _heartbeat_map;
  89   }
  90
  91   /**
  92    * Enable the performance counter, currently we only have counter for the
  93    * number of total/unhealthy workers.
  94    */
  95   void enable_perf_counter();
  96
  97   /**
  98    * Disable the performance counter.
  99    */
 100   void disable_perf_counter();
 101
 102   /**
 103    * Refresh perf counter values.
 104    */
 105   void refresh_perf_values();
 106
 107   /**
 108    * Get the admin socket associated with this CephContext.
 109    *
 110    * Currently there is always an admin socket object,
 111    * so this will never return NULL.
 112    *
 113    * @return the admin socket
 114    */
 115   AdminSocket *get_admin_socket();
 116
 117   /**
 118    * process an admin socket command
 119    */
 120   void do_command(std::string command, cmdmap_t& cmdmap, std::string format,
 121                   ceph::bufferlist *out);
 122
 123   template<typename T>
 124   void lookup_or_create_singleton_object(T*& p, const std::string &name) {
 125     ceph_spin_lock(&_associated_objs_lock);
 126     if (!_associated_objs.count(name)) {
 127       p = new T(this);
 128       _associated_objs[name] = new TypedSingletonWrapper<T>(p);
 129     } else {
 130       TypedSingletonWrapper<T> *wrapper =
 131         dynamic_cast<TypedSingletonWrapper<T> *>(_associated_objs[name]);
 132       assert(wrapper != NULL);
 133       p = wrapper->singleton;
 134     }
 135     ceph_spin_unlock(&_associated_objs_lock);
 136   }
 137   /**
 138    * get a crypto handler
 139    */
 140   CryptoHandler *get_crypto_handler(int type);
 141
 142   /// check if experimental feature is enable, and emit appropriate warnings
 143   bool check_experimental_feature_enabled(const std::string& feature);
 144   bool check_experimental_feature_enabled(const std::string& feature,
 145                                           std::ostream *message);
 146
 147   PluginRegistry *get_plugin_registry() {
 148     return _plugin_registry;
 149   }
 150
 151   void set_uid_gid(uid_t u, gid_t g) {
 152     _set_uid = u;
 153     _set_gid = g;
 154   }
 155   uid_t get_set_uid() const {
 156     return _set_uid;
 157   }
 158   gid_t get_set_gid() const {
 159     return _set_gid;
 160   }
 161
 162   void set_uid_gid_strings(std::string u, std::string g) {
 163     _set_uid_string = u;
 164     _set_gid_string = g;
 165   }
 166   std::string get_set_uid_string() const {
 167     return _set_uid_string;
 168   }
 169   std::string get_set_gid_string() const {
 170     return _set_gid_string;
 171   }
 172
 173   class ForkWatcher {
 174    public:
 175     virtual ~ForkWatcher() {}
 176     virtual void handle_pre_fork() = 0;
 177     virtual void handle_post_fork() = 0;
 178   };
 179
 180   void register_fork_watcher(ForkWatcher *w) {
 181     ceph_spin_lock(&_fork_watchers_lock);
 182     _fork_watchers.push_back(w);
 183     ceph_spin_unlock(&_fork_watchers_lock);
 184   }
 185
 186   void notify_pre_fork() {
 187     ceph_spin_lock(&_fork_watchers_lock);
 188     for (auto &&t : _fork_watchers)
 189       t->handle_pre_fork();
 190     ceph_spin_unlock(&_fork_watchers_lock);
 191   }
 192
 193   void notify_post_fork() {
 194     ceph_spin_lock(&_fork_watchers_lock);
 195     for (auto &&t : _fork_watchers)
 196       t->handle_post_fork();
 197     ceph_spin_unlock(&_fork_watchers_lock);
 198   }
 199
 200 private:
 201   struct SingletonWrapper : boost::noncopyable {
 202     virtual ~SingletonWrapper() {}
 203   };
 204
 205   template <typename T>
 206   struct TypedSingletonWrapper : public SingletonWrapper {
 207     TypedSingletonWrapper(T *p) : singleton(p) {
 208     }
 209     ~TypedSingletonWrapper() override {
 210       delete singleton;
 211     }
 212
 213     T *singleton;
 214   };
 215
 216   CephContext(const CephContext &rhs);
 217   CephContext &operator=(const CephContext &rhs);
 218
 219   /* Stop and join the Ceph Context's service thread */
 220   void join_service_thread();
 221
 222   uint32_t _module_type;
 223
 224   int _init_flags;
 225
 226   uid_t _set_uid; ///< uid to drop privs to
 227   gid_t _set_gid; ///< gid to drop privs to
 228   std::string _set_uid_string;
 229   std::string _set_gid_string;
 230
 231   bool _crypto_inited;
 232
 233   /* libcommon service thread.
 234    * SIGHUP wakes this thread, which then reopens logfiles */
 235   friend class CephContextServiceThread;
 236   CephContextServiceThread *_service_thread;
 237
 238   md_config_obs_t *_log_obs;
 239
 240   /* The admin socket associated with this context */
 241   AdminSocket *_admin_socket;
 242
 243   /* lock which protects service thread creation, destruction, etc. */
 244   ceph_spinlock_t _service_thread_lock;
 245
 246   /* The collection of profiling loggers associated with this context */
 247   PerfCountersCollection *_perf_counters_collection;
 248
 249   md_config_obs_t *_perf_counters_conf_obs;
 250
 251   CephContextHook *_admin_hook;
 252
 253   ceph::HeartbeatMap *_heartbeat_map;
 254
 255   ceph_spinlock_t _associated_objs_lock;
 256   std::map<std::string, SingletonWrapper*> _associated_objs;
 257
 258   ceph_spinlock_t _fork_watchers_lock;
 259   std::vector<ForkWatcher*> _fork_watchers;
 260
 261   // crypto
 262   CryptoHandler *_crypto_none;
 263   CryptoHandler *_crypto_aes;
 264
 265   // experimental
 266   CephContextObs *_cct_obs;
 267   ceph_spinlock_t _feature_lock;
 268   std::set<std::string> _experimental_features;
 269
 270   PluginRegistry *_plugin_registry;
 271
 272   md_config_obs_t *_lockdep_obs;
 273
 274 public:
 275   CrushLocation crush_location;
 276 private:
 277
 278   enum {
 279     l_cct_first,
 280     l_cct_total_workers,
 281     l_cct_unhealthy_workers,
 282     l_cct_last
 283   };
 284   PerfCounters *_cct_perf;
 285   ceph_spinlock_t _cct_perf_lock;
 286
 287   friend class CephContextObs;
 288 };
 289
 290 #endif