// -*- 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) 2011 New Dream Network/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.
	 * 
	 */
	
	#include "acconfig.h"
	
	// Use the newer gperftools header locations if available.
	// If not, fall back to the old (gperftools < 2.0) locations.
	
	#include <gperftools/heap-profiler.h>
	#include <gperftools/malloc_extension.h>
	
	#include "heap_profiler.h"
	#include "common/environment.h"
	#include "common/LogClient.h"
	#include "global/global_context.h"
	#include "common/debug.h"
	
	#define dout_context g_ceph_context
	
	bool ceph_using_tcmalloc()
	{
	  return true;
	}
	
	void ceph_heap_profiler_init()
	{
	  // Two other interesting environment variables to set are:
	  // HEAP_PROFILE_ALLOCATION_INTERVAL, HEAP_PROFILE_INUSE_INTERVAL
	  if (get_env_bool("CEPH_HEAP_PROFILER_INIT")) {
	    ceph_heap_profiler_start();
	  }
	}
	
	void ceph_heap_profiler_stats(char *buf, int length)
	{
	  MallocExtension::instance()->GetStats(buf, length);
	}
	
	void ceph_heap_release_free_memory()
	{
	  MallocExtension::instance()->ReleaseFreeMemory();
	}
	
	double ceph_heap_get_release_rate()
	{
	  return MallocExtension::instance()->GetMemoryReleaseRate();
	}
	
	void ceph_heap_set_release_rate(double val)
	{
	  MallocExtension::instance()->SetMemoryReleaseRate(val);
	}
	
	bool ceph_heap_get_numeric_property(
	  const char *property, size_t *value)
	{
	  return MallocExtension::instance()->GetNumericProperty(
	    property,
	    value);
	}
	
	bool ceph_heap_set_numeric_property(
	  const char *property, size_t value)
	{
	  return MallocExtension::instance()->SetNumericProperty(
	    property,
	    value);
	}
	
	bool ceph_heap_profiler_running()
	{
	#ifdef HAVE_LIBTCMALLOC
	  return IsHeapProfilerRunning();
	#else
	  return false;
	#endif
	}
	
	static void get_profile_name(char *profile_name, int profile_name_len)
	{
	#if __GNUC__ && __GNUC__ >= 8
	#pragma GCC diagnostic push
	  // Don't care, it doesn't matter, and we can't do anything about it.
	#pragma GCC diagnostic ignored "-Wformat-truncation"
	#endif
	
	  char path[PATH_MAX];
	  snprintf(path, sizeof(path), "%s", g_conf()->log_file.c_str());
	  char *last_slash = rindex(path, '/');
	
	  if (last_slash == NULL) {
	    snprintf(profile_name, profile_name_len, "./%s.profile",
		     g_conf()->name.to_cstr());
	  }
	  else {
	    last_slash[1] = '\0';
	    snprintf(profile_name, profile_name_len, "%s/%s.profile",
		     path, g_conf()->name.to_cstr());
	  }
	#if __GNUC__ && __GNUC__ >= 8
	#pragma GCC diagnostic pop
	#endif
	}
	
	void ceph_heap_profiler_start()
	{
	#ifdef HAVE_LIBTCMALLOC
	  char profile_name[PATH_MAX];
	  get_profile_name(profile_name, sizeof(profile_name)); 
	  generic_dout(0) << "turning on heap profiler with prefix "
			  << profile_name << dendl;
	  HeapProfilerStart(profile_name);
	#endif
	}
	
	void ceph_heap_profiler_stop()
	{
	#ifdef HAVE_LIBTCMALLOC
	  HeapProfilerStop();
	#endif
	}
	
	void ceph_heap_profiler_dump(const char *reason)
	{
	#ifdef HAVE_LIBTCMALLOC
	  HeapProfilerDump(reason);
	#endif
	}
	
	#define HEAP_PROFILER_STATS_SIZE 2048
	
	void ceph_heap_profiler_handle_command(const std::vector<std::string>& cmd,
	                                       ostream& out)
	{
	#ifdef HAVE_LIBTCMALLOC

	  if (cmd.size() == 1 && cmd[0] == "dump") {
	    if (!ceph_heap_profiler_running()) {
	      out << "heap profiler not running; can't dump";
	      return;
	    }
	    char heap_stats[HEAP_PROFILER_STATS_SIZE];
	    ceph_heap_profiler_stats(heap_stats, sizeof(heap_stats));
	    out << g_conf()->name << " dumping heap profile now.\n"
		<< heap_stats;
	    ceph_heap_profiler_dump("admin request");

	  } else if (cmd.size() == 1 && cmd[0] == "start_profiler") {
	    ceph_heap_profiler_start();
	    out << g_conf()->name << " started profiler";

	  } else if (cmd.size() == 1 && cmd[0] == "stop_profiler") {
	    ceph_heap_profiler_stop();
	    out << g_conf()->name << " stopped profiler";

	  } else if (cmd.size() == 1 && cmd[0] == "release") {
	    ceph_heap_release_free_memory();
	    out << g_conf()->name << " releasing free RAM back to system.";

	  } else if (cmd.size() == 1 && cmd[0] == "get_release_rate") {
	    out << g_conf()->name << " release rate: " 
		<< std::setprecision(4) << ceph_heap_get_release_rate() << "\n";

	  } else if (cmd.size() == 2 && cmd[0] == "set_release_rate") {
	    try {
	      double val = std::stod(cmd[1]);
	      ceph_heap_set_release_rate(val);

	      out << g_conf()->name <<  " release rate changed to: " 
	          << std::setprecision(4) << ceph_heap_get_release_rate() << "\n";

	    } catch (...) {
	      out << g_conf()->name <<  " *** need an numerical value. ";

	    }

	  } else
	#endif
	  if (cmd.size() == 1 && cmd[0] == "stats") {
	    char heap_stats[HEAP_PROFILER_STATS_SIZE];
	    ceph_heap_profiler_stats(heap_stats, sizeof(heap_stats));
	    out << g_conf()->name << " tcmalloc heap stats:"
		<< heap_stats;
	  } else {
	    out << "unknown command " << cmd;

	  }

	}