profiler_trace.h
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// -*- C++ -*-
//
// Copyright (C) 2009-2013 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
/** @file profile/impl/profiler_trace.h
* @brief Data structures to represent profiling traces.
*/
// Written by Lixia Liu and Silvius Rus.
#ifndef _GLIBCXX_PROFILE_PROFILER_TRACE_H
#define _GLIBCXX_PROFILE_PROFILER_TRACE_H 1
#include <cstdio> // fopen, fclose, fprintf, FILE
#include <cerrno>
#include <cstdlib> // atof, atoi, strtol, getenv, atexit, abort
#if __cplusplus >= 201103L
#define _GLIBCXX_IMPL_UNORDERED_MAP std::_GLIBCXX_STD_C::unordered_map
#include <unordered_map>
#else
#include <tr1/unordered_map>
#define _GLIBCXX_IMPL_UNORDERED_MAP std::tr1::unordered_map
#endif
#include <ext/concurrence.h>
#include <fstream>
#include <string>
#include <utility>
#include <vector>
#include "profile/impl/profiler_algos.h"
#include "profile/impl/profiler_state.h"
#include "profile/impl/profiler_node.h"
namespace __gnu_profile
{
/** @brief Internal environment. Values can be set one of two ways:
1. In config file "var = value". The default config file path is
libstdcxx-profile.conf.
2. By setting process environment variables. For instance, in a Bash
shell you can set the unit cost of iterating through a map like this:
export __map_iterate_cost_factor=5.0.
If a value is set both in the input file and through an environment
variable, the environment value takes precedence. */
typedef _GLIBCXX_IMPL_UNORDERED_MAP<std::string, std::string> __env_t;
_GLIBCXX_PROFILE_DEFINE_UNINIT_DATA(__env_t, __env);
/** @brief Master lock. */
_GLIBCXX_PROFILE_DEFINE_UNINIT_DATA(__gnu_cxx::__mutex, __global_lock);
/** @brief Representation of a warning. */
struct __warning_data
{
float __magnitude;
__stack_t __context;
const char* __warning_id;
std::string __warning_message;
__warning_data()
: __magnitude(0.0), __context(0), __warning_id(0) { }
__warning_data(float __m, __stack_t __c, const char* __id,
const std::string& __msg)
: __magnitude(__m), __context(__c), __warning_id(__id),
__warning_message(__msg) { }
bool
operator<(const __warning_data& __other) const
{ return __magnitude < __other.__magnitude; }
};
typedef std::_GLIBCXX_STD_C::vector<__warning_data> __warning_vector_t;
// Defined in profiler_<diagnostic name>.h.
class __trace_hash_func;
class __trace_hashtable_size;
class __trace_map2umap;
class __trace_vector_size;
class __trace_vector_to_list;
class __trace_list_to_slist;
class __trace_list_to_vector;
void __trace_vector_size_init();
void __trace_hashtable_size_init();
void __trace_hash_func_init();
void __trace_vector_to_list_init();
void __trace_list_to_slist_init();
void __trace_list_to_vector_init();
void __trace_map_to_unordered_map_init();
void __trace_vector_size_report(FILE*, __warning_vector_t&);
void __trace_hashtable_size_report(FILE*, __warning_vector_t&);
void __trace_hash_func_report(FILE*, __warning_vector_t&);
void __trace_vector_to_list_report(FILE*, __warning_vector_t&);
void __trace_list_to_slist_report(FILE*, __warning_vector_t&);
void __trace_list_to_vector_report(FILE*, __warning_vector_t&);
void __trace_map_to_unordered_map_report(FILE*, __warning_vector_t&);
struct __cost_factor
{
const char* __env_var;
float __value;
};
typedef std::_GLIBCXX_STD_C::vector<__cost_factor*> __cost_factor_vector;
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_hash_func*, _S_hash_func, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_hashtable_size*, _S_hashtable_size, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_map2umap*, _S_map2umap, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_vector_size*, _S_vector_size, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_vector_to_list*, _S_vector_to_list, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_list_to_slist*, _S_list_to_slist, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__trace_list_to_vector*, _S_list_to_vector, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __vector_shift_cost_factor,
{"__vector_shift_cost_factor", 1.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __vector_iterate_cost_factor,
{"__vector_iterate_cost_factor", 1.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __vector_resize_cost_factor,
{"__vector_resize_cost_factor", 1.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __list_shift_cost_factor,
{"__list_shift_cost_factor", 0.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __list_iterate_cost_factor,
{"__list_iterate_cost_factor", 10.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __list_resize_cost_factor,
{"__list_resize_cost_factor", 0.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __map_insert_cost_factor,
{"__map_insert_cost_factor", 1.5});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __map_erase_cost_factor,
{"__map_erase_cost_factor", 1.5});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __map_find_cost_factor,
{"__map_find_cost_factor", 1});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __map_iterate_cost_factor,
{"__map_iterate_cost_factor", 2.3});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __umap_insert_cost_factor,
{"__umap_insert_cost_factor", 12.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __umap_erase_cost_factor,
{"__umap_erase_cost_factor", 12.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __umap_find_cost_factor,
{"__umap_find_cost_factor", 10.0});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor, __umap_iterate_cost_factor,
{"__umap_iterate_cost_factor", 1.7});
_GLIBCXX_PROFILE_DEFINE_DATA(__cost_factor_vector*, __cost_factors, 0);
_GLIBCXX_PROFILE_DEFINE_DATA(const char*, _S_trace_file_name,
_GLIBCXX_PROFILE_TRACE_PATH_ROOT);
_GLIBCXX_PROFILE_DEFINE_DATA(std::size_t, _S_max_warn_count,
_GLIBCXX_PROFILE_MAX_WARN_COUNT);
_GLIBCXX_PROFILE_DEFINE_DATA(std::size_t, _S_max_stack_depth,
_GLIBCXX_PROFILE_MAX_STACK_DEPTH);
_GLIBCXX_PROFILE_DEFINE_DATA(std::size_t, _S_max_mem,
_GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC);
inline std::size_t
__stack_max_depth()
{ return _GLIBCXX_PROFILE_DATA(_S_max_stack_depth); }
inline std::size_t
__max_mem()
{ return _GLIBCXX_PROFILE_DATA(_S_max_mem); }
/** @brief Base class for all trace producers. */
template<typename __object_info, typename __stack_info>
class __trace_base
{
public:
// Do not pick the initial size too large, as we don't know which
// diagnostics are more active.
__trace_base()
: __object_table(10000), __stack_table(10000),
__stack_table_byte_size(0), __id(0) { }
virtual ~__trace_base() { }
void __add_object(__object_t object, __object_info __info);
__object_info* __get_object_info(__object_t __object);
void __retire_object(__object_t __object);
void __write(FILE* __f);
void __collect_warnings(__warning_vector_t& __warnings);
private:
__gnu_cxx::__mutex __object_table_lock;
__gnu_cxx::__mutex __stack_table_lock;
typedef _GLIBCXX_IMPL_UNORDERED_MAP<__object_t,
__object_info> __object_table_t;
typedef _GLIBCXX_IMPL_UNORDERED_MAP<__stack_t, __stack_info,
__stack_hash,
__stack_hash> __stack_table_t;
__object_table_t __object_table;
__stack_table_t __stack_table;
std::size_t __stack_table_byte_size;
protected:
const char* __id;
};
template<typename __object_info, typename __stack_info>
void
__trace_base<__object_info, __stack_info>::
__collect_warnings(__warning_vector_t& __warnings)
{
for (typename __stack_table_t::iterator __it
= __stack_table.begin(); __it != __stack_table.end(); ++__it)
__warnings.push_back(__warning_data((*__it).second.__magnitude(),
(*__it).first, __id,
(*__it).second.__advice()));
}
template<typename __object_info, typename __stack_info>
void
__trace_base<__object_info, __stack_info>::
__add_object(__object_t __object, __object_info __info)
{
if (__max_mem() == 0
|| __object_table.size() * sizeof(__object_info) <= __max_mem())
{
this->__object_table_lock.lock();
__object_table.insert(typename __object_table_t::
value_type(__object, __info));
this->__object_table_lock.unlock();
}
}
template<typename __object_info, typename __stack_info>
__object_info*
__trace_base<__object_info, __stack_info>::
__get_object_info(__object_t __object)
{
// XXX: Revisit this to see if we can decrease mutex spans.
// Without this mutex, the object table could be rehashed during an
// insertion on another thread, which could result in a segfault.
this->__object_table_lock.lock();
typename __object_table_t::iterator __object_it
= __object_table.find(__object);
if (__object_it == __object_table.end())
{
this->__object_table_lock.unlock();
return 0;
}
else
{
this->__object_table_lock.unlock();
return &__object_it->second;
}
}
template<typename __object_info, typename __stack_info>
void
__trace_base<__object_info, __stack_info>::
__retire_object(__object_t __object)
{
this->__object_table_lock.lock();
this->__stack_table_lock.lock();
typename __object_table_t::iterator __object_it
= __object_table.find(__object);
if (__object_it != __object_table.end())
{
const __object_info& __info = __object_it->second;
const __stack_t& __stack = __info.__stack();
typename __stack_table_t::iterator __stack_it
= __stack_table.find(__stack);
if (__stack_it == __stack_table.end())
{
// First occurrence of this call context.
if (__max_mem() == 0 || __stack_table_byte_size < __max_mem())
{
__stack_table_byte_size
+= (sizeof(__instruction_address_t) * __size(__stack)
+ sizeof(__stack) + sizeof(__stack_info));
__stack_table.insert(make_pair(__stack,
__stack_info(__info)));
}
}
else
{
// Merge object info into info summary for this call context.
__stack_it->second.__merge(__info);
delete __stack;
}
__object_table.erase(__object);
}
this->__object_table_lock.unlock();
this->__stack_table_lock.unlock();
}
template<typename __object_info, typename __stack_info>
void
__trace_base<__object_info, __stack_info>::
__write(FILE* __f)
{
for (typename __stack_table_t::iterator __it
= __stack_table.begin(); __it != __stack_table.end(); ++__it)
if (__it->second.__is_valid())
{
std::fprintf(__f, __id);
std::fprintf(__f, "|");
__gnu_profile::__write(__f, __it->first);
std::fprintf(__f, "|");
__it->second.__write(__f);
}
}
inline std::size_t
__env_to_size_t(const char* __env_var, std::size_t __default_value)
{
char* __env_value = std::getenv(__env_var);
if (__env_value)
{
errno = 0;
long __converted_value = std::strtol(__env_value, 0, 10);
if (errno || __converted_value < 0)
{
std::fprintf(stderr,
"Bad value for environment variable '%s'.\n",
__env_var);
std::abort();
}
else
return static_cast<std::size_t>(__converted_value);
}
else
return __default_value;
}
inline void
__set_max_stack_trace_depth()
{
_GLIBCXX_PROFILE_DATA(_S_max_stack_depth)
= __env_to_size_t(_GLIBCXX_PROFILE_MAX_STACK_DEPTH_ENV_VAR,
_GLIBCXX_PROFILE_DATA(_S_max_stack_depth));
}
inline void
__set_max_mem()
{
_GLIBCXX_PROFILE_DATA(_S_max_mem)
= __env_to_size_t(_GLIBCXX_PROFILE_MEM_PER_DIAGNOSTIC_ENV_VAR,
_GLIBCXX_PROFILE_DATA(_S_max_mem));
}
inline int
__log_magnitude(float __f)
{
const float __log_base = 10.0;
int __result = 0;
int __sign = 1;
if (__f < 0)
{
__f = -__f;
__sign = -1;
}
while (__f > __log_base)
{
++__result;
__f /= 10.0;
}
return __sign * __result;
}
inline FILE*
__open_output_file(const char* __extension)
{
// The path is made of _S_trace_file_name + "." + extension.
std::size_t __root_len
= __builtin_strlen(_GLIBCXX_PROFILE_DATA(_S_trace_file_name));
std::size_t __ext_len = __builtin_strlen(__extension);
char* __file_name = new char[__root_len + 1 + __ext_len + 1];
__builtin_memcpy(__file_name,
_GLIBCXX_PROFILE_DATA(_S_trace_file_name),
__root_len);
*(__file_name + __root_len) = '.';
__builtin_memcpy(__file_name + __root_len + 1,
__extension, __ext_len + 1);
FILE* __out_file = std::fopen(__file_name, "w");
if (!__out_file)
{
std::fprintf(stderr, "Could not open trace file '%s'.\n",
__file_name);
std::abort();
}
delete[] __file_name;
return __out_file;
}
struct __warn
{
FILE* __file;
__warn(FILE* __f)
{ __file = __f; }
void
operator()(const __warning_data& __info)
{
std::fprintf(__file, __info.__warning_id);
std::fprintf(__file, ": improvement = %d",
__log_magnitude(__info.__magnitude));
std::fprintf(__file, ": call stack = ");
__gnu_profile::__write(__file, __info.__context);
std::fprintf(__file, ": advice = %s\n",
__info.__warning_message.c_str());
}
};
/** @brief Final report method, registered with @b atexit.
*
* This can also be called directly by user code, including signal handlers.
* It is protected against deadlocks by the reentrance guard in profiler.h.
* However, when called from a signal handler that triggers while within
* __gnu_profile (under the guarded zone), no output will be produced.
*/
inline void
__report(void)
{
_GLIBCXX_PROFILE_DATA(__global_lock).lock();
__warning_vector_t __warnings, __top_warnings;
FILE* __raw_file = __open_output_file("raw");
__trace_vector_size_report(__raw_file, __warnings);
__trace_hashtable_size_report(__raw_file, __warnings);
__trace_hash_func_report(__raw_file, __warnings);
__trace_vector_to_list_report(__raw_file, __warnings);
__trace_list_to_slist_report(__raw_file, __warnings);
__trace_list_to_vector_report(__raw_file, __warnings);
__trace_map_to_unordered_map_report(__raw_file, __warnings);
std::fclose(__raw_file);
// Sort data by magnitude, keeping just top N.
std::size_t __cutoff = std::min(_GLIBCXX_PROFILE_DATA(_S_max_warn_count),
__warnings.size());
__top_n(__warnings, __top_warnings, __cutoff);
FILE* __warn_file = __open_output_file("txt");
__for_each(__top_warnings.begin(), __top_warnings.end(),
__warn(__warn_file));
std::fclose(__warn_file);
_GLIBCXX_PROFILE_DATA(__global_lock).unlock();
}
inline void
__set_trace_path()
{
char* __env_trace_file_name = std::getenv(_GLIBCXX_PROFILE_TRACE_ENV_VAR);
if (__env_trace_file_name)
_GLIBCXX_PROFILE_DATA(_S_trace_file_name) = __env_trace_file_name;
// Make sure early that we can create the trace file.
std::fclose(__open_output_file("txt"));
}
inline void
__set_max_warn_count()
{
char* __env_max_warn_count_str
= std::getenv(_GLIBCXX_PROFILE_MAX_WARN_COUNT_ENV_VAR);
if (__env_max_warn_count_str)
_GLIBCXX_PROFILE_DATA(_S_max_warn_count)
= static_cast<std::size_t>(std::atoi(__env_max_warn_count_str));
}
inline void
__read_cost_factors()
{
std::string __conf_file_name(_GLIBCXX_PROFILE_DATA(_S_trace_file_name));
__conf_file_name += ".conf";
std::ifstream __conf_file(__conf_file_name.c_str());
if (__conf_file.is_open())
{
std::string __line;
while (std::getline(__conf_file, __line))
{
std::string::size_type __i = __line.find_first_not_of(" \t\n\v");
if (__line.length() <= 0 || __line[__i] == '#')
// Skip empty lines or comments.
continue;
}
// Trim.
__line.erase(__remove(__line.begin(), __line.end(), ' '),
__line.end());
std::string::size_type __pos = __line.find("=");
std::string __factor_name = __line.substr(0, __pos);
std::string::size_type __end = __line.find_first_of(";\n");
std::string __factor_value = __line.substr(__pos + 1, __end - __pos);
_GLIBCXX_PROFILE_DATA(__env)[__factor_name] = __factor_value;
}
}
struct __cost_factor_writer
{
FILE* __file;
__cost_factor_writer(FILE* __f)
: __file(__f) { }
void
operator() (const __cost_factor* __factor)
{ std::fprintf(__file, "%s = %f\n", __factor->__env_var,
__factor->__value); }
};
inline void
__write_cost_factors()
{
FILE* __file = __open_output_file("conf.out");
__for_each(_GLIBCXX_PROFILE_DATA(__cost_factors)->begin(),
_GLIBCXX_PROFILE_DATA(__cost_factors)->end(),
__cost_factor_writer(__file));
std::fclose(__file);
}
struct __cost_factor_setter
{
void
operator()(__cost_factor* __factor)
{
// Look it up in the process environment first.
const char* __env_value = std::getenv(__factor->__env_var);
if (!__env_value)
{
// Look it up in the config file.
__env_t::iterator __it
= _GLIBCXX_PROFILE_DATA(__env).find(__factor->__env_var);
if (__it != _GLIBCXX_PROFILE_DATA(__env).end())
__env_value = (*__it).second.c_str();
}
if (__env_value)
__factor->__value = std::atof(__env_value);
}
};
inline void
__set_cost_factors()
{
_GLIBCXX_PROFILE_DATA(__cost_factors) = new __cost_factor_vector;
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__vector_shift_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__vector_iterate_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__vector_resize_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__list_shift_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__list_iterate_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__list_resize_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__map_insert_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__map_erase_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__map_find_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__map_iterate_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__umap_insert_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__umap_erase_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__umap_find_cost_factor));
_GLIBCXX_PROFILE_DATA(__cost_factors)->
push_back(&_GLIBCXX_PROFILE_DATA(__umap_iterate_cost_factor));
__for_each(_GLIBCXX_PROFILE_DATA(__cost_factors)->begin(),
_GLIBCXX_PROFILE_DATA(__cost_factors)->end(),
__cost_factor_setter());
}
inline void
__profcxx_init_unconditional()
{
_GLIBCXX_PROFILE_DATA(__global_lock).lock();
if (__is_invalid())
{
__set_max_warn_count();
if (_GLIBCXX_PROFILE_DATA(_S_max_warn_count) == 0)
__turn_off();
else
{
__set_max_stack_trace_depth();
__set_max_mem();
__set_trace_path();
__read_cost_factors();
__set_cost_factors();
__write_cost_factors();
__trace_vector_size_init();
__trace_hashtable_size_init();
__trace_hash_func_init();
__trace_vector_to_list_init();
__trace_list_to_slist_init();
__trace_list_to_vector_init();
__trace_map_to_unordered_map_init();
std::atexit(__report);
__turn_on();
}
}
_GLIBCXX_PROFILE_DATA(__global_lock).unlock();
}
/** @brief This function must be called by each instrumentation point.
*
* The common path is inlined fully.
*/
inline bool
__profcxx_init()
{
if (__is_invalid())
__profcxx_init_unconditional();
return __is_on();
}
} // namespace __gnu_profile
#endif /* _GLIBCXX_PROFILE_PROFILER_TRACE_H */