pdns/malloctrace.hh

   1 /*
   2  * This file is part of PowerDNS or dnsdist.
   3  * Copyright -- PowerDNS.COM B.V. and its contributors
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * In addition, for the avoidance of any doubt, permission is granted to
  10  * link this program with OpenSSL and to (re)distribute the binaries
  11  * produced as the result of such linking.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22 #pragma once
  23 #include <string>
  24 #include <atomic>
  25 #include <stdint.h>
  26 #include <mutex>
  27 #include <map>
  28 #include <vector>
  29
  30 /* please do NOT add PowerDNS specific includes/things to this file, we're trying
  31    to make it useful for other projects as well! */
  32
  33 /* Goal: you can compile this in safely, but it won't do anything unless PDNS_TRACE_MEMORY is defined. */
  34
  35 class MallocTracer
  36 {
  37 public:
  38   void* malloc (size_t size);
  39   void free(void*);
  40   uint64_t getAllocs(const std::string& = std::string()) const { return d_allocs; }
  41   uint64_t getAllocFlux(const std::string& = std::string()) const { return d_allocflux; }
  42   uint64_t getTotAllocated(const std::string& = std::string()) const { return d_totAllocated; }
  43   uint64_t getNumOut() { std::lock_guard<std::mutex> lock(d_mut); return d_sizes.size(); }
  44   struct AllocStats
  45   {
  46     int count;
  47     std::map<unsigned int, unsigned int> sizes;
  48   };
  49   typedef std::vector<std::pair<MallocTracer::AllocStats,
  50                                 std::vector<void*> > > allocators_t;
  51   allocators_t topAllocators(int num=-1);
  52   std::string topAllocatorsString(int num=-1);
  53   void clearAllocators();
  54
  55 private:
  56   static std::vector<void*> makeBacktrace();
  57   std::atomic<uint64_t> d_allocs{0}, d_allocflux{0}, d_totAllocated{0};
  58   std::map<std::vector<void*>, AllocStats> d_stats;
  59   std::map<void*, size_t> d_sizes;
  60   std::mutex d_mut;
  61 };
  62
  63 extern MallocTracer* g_mtracer;