+++ /dev/null
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-// vim: ts=8 sw=2 smarttab
-/*
- * Ceph - scalable distributed file system
- *
- * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
- *
- * This is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License version 2.1, as published by the Free Software
- * Foundation. See file COPYING.
- *
- */
-
-#ifndef CEPH_COMMON_MUTEX_DEBUG_H
-#define CEPH_COMMON_MUTEX_DEBUG_H
-
-#include <system_error>
-#include <thread>
-
-#include <pthread.h>
-
-#include "include/assert.h"
-
-#include "ceph_time.h"
-#include "likely.h"
-#include "lockdep.h"
-
-class CephContext;
-class PerfCounters;
-
-namespace ceph {
-namespace mutex_debug_detail {
-class mutex_debugging_base {
-protected:
- std::string name;
- int id;
- bool backtrace; // gather backtrace on lock acquisition
-
- int nlock;
- std::thread::id locked_by;
- CephContext *cct;
- PerfCounters *logger;
-
- void _register();
- void _will_lock(); // about to lock
- void _locked(); // just locked
- void _will_unlock(); // about to unlock
-
- mutex_debugging_base(const std::string &n = std::string(), bool bt = false,
- CephContext *cct = nullptr);
- ~mutex_debugging_base();
-
- ceph::mono_time before_lock_blocks();
- void after_lock_blocks(ceph::mono_time start,
- bool no_lockdep);
-
-public:
- bool is_locked() const {
- return (nlock > 0);
- }
- bool is_locked_by_me() const {
- return nlock > 0 && locked_by == std::this_thread::get_id();
- }
- operator bool() const {
- return nlock > 0 && locked_by == std::this_thread::get_id();
- }
-};
-
-template<typename Mutex>
-class mutex_debugging : public mutex_debugging_base {
- Mutex* impl;
-
-public:
- mutex_debugging(const std::string &n = std::string(), bool bt = false,
- CephContext *cct = nullptr) :
- mutex_debugging_base(n, bt, cct), impl(static_cast<Mutex*>(this)) {}
-
- ~mutex_debugging() = default;
-
- void _post_lock() {
- if (!impl->recursive)
- assert(nlock == 0);
- locked_by = std::this_thread::get_id();
- nlock++;
- }
-
- void _pre_unlock() {
- assert(nlock > 0);
- --nlock;
- assert(locked_by == std::this_thread::get_id());
- if (!impl->recursive)
- assert(nlock == 0);
- if (nlock == 0)
- locked_by = std::thread::id();
- }
-
- bool try_lock(bool no_lockdep = false) {
- bool locked = impl->try_lock_impl();
- if (locked) {
- if (g_lockdep && !no_lockdep)
- _locked();
- _post_lock();
- }
- return locked;
- }
-
- void lock(bool no_lockdep = false) {
- if (g_lockdep && !no_lockdep)
- _will_lock();
-
- if (try_lock())
- return;
-
- auto t = before_lock_blocks();
- impl->lock_impl();
- after_lock_blocks(t, no_lockdep);
- _post_lock();
- }
-
- void unlock(bool no_lockdep = false) {
- _pre_unlock();
- if (!no_lockdep && g_lockdep)
- _will_unlock();
- impl->unlock_impl();
- }
-};
-
-// Since this is a /debugging/ mutex just define it in terms of the
-// pthread error check mutex.
-template<bool Recursive>
-class mutex_debug_impl : public mutex_debugging<mutex_debug_impl<Recursive> > {
-private:
- pthread_mutex_t m;
-public:
- static constexpr bool recursive = Recursive;
-
- // Mutex concept is DefaultConstructible
- mutex_debug_impl(const std::string &n = std::string(), bool bt = false,
- CephContext *cct = nullptr) :
- mutex_debugging<mutex_debug_impl<Recursive> >(n, bt, cct) {
- pthread_mutexattr_t a;
- pthread_mutexattr_init(&a);
- int r;
- if (recursive)
- r = pthread_mutexattr_settype(&a, PTHREAD_MUTEX_RECURSIVE);
- else
- r = pthread_mutexattr_settype(&a, PTHREAD_MUTEX_ERRORCHECK);
- assert(r == 0);
- r = pthread_mutex_init(&m, &a);
- assert(r == 0);
- }
- // Mutex is Destructible
- ~mutex_debug_impl() {
- int r = pthread_mutex_destroy(&m);
- assert(r == 0);
- }
-
- // Mutex concept is non-Copyable
- mutex_debug_impl(const mutex_debug_impl&) = delete;
- mutex_debug_impl& operator =(const mutex_debug_impl&) = delete;
-
- // Mutex concept is non-Movable
- mutex_debug_impl(mutex_debug_impl&&) = delete;
- mutex_debug_impl& operator =(mutex_debug_impl&&) = delete;
-
- void lock_impl() {
- int r = pthread_mutex_lock(&m);
- // Allowed error codes for Mutex concept
- if (unlikely(r == EPERM ||
- r == EDEADLK ||
- r == EBUSY)) {
- throw std::system_error(r, std::generic_category());
- }
- assert(r == 0);
- }
-
- void unlock_impl() noexcept {
- int r = pthread_mutex_unlock(&m);
- assert(r == 0);
- }
-
- bool try_lock_impl() {
- int r = pthread_mutex_trylock(&m);
- switch (r) {
- case 0:
- return true;
- case EBUSY:
- return false;
- default:
- throw std::system_error(r, std::generic_category());
- }
- }
-};
-} // namespace mutex_debug_detail
-typedef mutex_debug_detail::mutex_debug_impl<false> mutex_debug;
-typedef mutex_debug_detail::mutex_debug_impl<true> mutex_recursive_debug;
-} // namespace ceph
-
-#endif
Code Review / stor4nfv.git / blobdiff