15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2007, Google Inc. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// All rights reserved. 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Redistribution and use in source and binary forms, with or without 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// modification, are permitted provided that the following conditions are 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// met: 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// * Redistributions of source code must retain the above copyright 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// notice, this list of conditions and the following disclaimer. 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// * Redistributions in binary form must reproduce the above 115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// copyright notice, this list of conditions and the following disclaimer 125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// in the documentation and/or other materials provided with the 135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// distribution. 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// * Neither the name of Google Inc. nor the names of its 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// contributors may be used to endorse or promote products derived from 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// this software without specific prior written permission. 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// --- 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Author: Sanjay Ghemawat 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Chris Demetriou (refactoring) 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Collect profiling data. 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// The profile data file format is documented in 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// doc/cpuprofile-fileformat.html 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#ifndef BASE_PROFILEDATA_H_ 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#define BASE_PROFILEDATA_H_ 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <config.h> 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <time.h> // for time_t 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include <stdint.h> 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/basictypes.h" 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// A class that accumulates profile samples and writes them to a file. 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Each sample contains a stack trace and a count. Memory usage is 515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// reduced by combining profile samples that have the same stack trace 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// by adding up the associated counts. 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Profile data is accumulated in a bounded amount of memory, and will 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// flushed to a file as necessary to stay within the memory limit. 565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this class assumes external synchronization. The exact 585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// requirements of that synchronization are that: 595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// - 'Add' may be called from asynchronous signals, but is not 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// re-entrant. 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// - None of 'Start', 'Stop', 'Reset', 'Flush', and 'Add' may be 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// called at the same time. 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// - 'Start', 'Stop', or 'Reset' should not be called while 'Enabled' 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// or 'GetCurrent' are running, and vice versa. 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// A profiler which uses asyncronous signals to add samples will 705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// typically use two locks to protect this data structure: 715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// - A SpinLock which is held over all calls except for the 'Add' 735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// call made from the signal handler. 745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// - A SpinLock which is held over calls to 'Start', 'Stop', 'Reset', 765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// 'Flush', and 'Add'. (This SpinLock should be acquired after 775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// the first SpinLock in all cases where both are needed.) 785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)class ProfileData { 795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) public: 805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct State { 815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) bool enabled; // Is profiling currently enabled? 825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) time_t start_time; // If enabled, when was profiling started? 835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) char profile_name[1024]; // Name of file being written, or '\0' 845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int samples_gathered; // Number of samples gathered to far (or 0) 855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }; 865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) class Options { 885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) public: 895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Options(); 905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Get and set the sample frequency. 925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int frequency() const { 935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return frequency_; 945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void set_frequency(int frequency) { 965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) frequency_ = frequency; 975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) private: 1005821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int frequency_; // Sample frequency. 1015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }; 1025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) static const int kMaxStackDepth = 64; // Max stack depth stored in profile 1045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ProfileData(); 1065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ~ProfileData(); 1075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // If data collection is not already enabled start to collect data 1095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // into fname. Parameters related to this profiling run are specified 1105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // by 'options'. 1115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // 1125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Returns true if data collection could be started, otherwise (if an 1135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // error occurred or if data collection was already enabled) returns 1145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // false. 1155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) bool Start(const char *fname, const Options& options); 1165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // If data collection is enabled, stop data collection and write the 1185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // data to disk. 1195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Stop(); 1205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Stop data collection without writing anything else to disk, and 1225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // discard any collected data. 1235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Reset(); 1245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // If data collection is enabled, record a sample with 'depth' 1265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // entries from 'stack'. (depth must be > 0.) At most 1275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // kMaxStackDepth stack entries will be recorded, starting with 1285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // stack[0]. 1295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // 1305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // This function is safe to call from asynchronous signals (but is 1315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // not re-entrant). 1325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Add(int depth, const void* const* stack); 1335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // If data collection is enabled, write the data to disk (and leave 1355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // the collector enabled). 1365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void FlushTable(); 1375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Is data collection currently enabled? 1395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) bool enabled() const { return out_ >= 0; } 1405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Get the current state of the data collector. 1425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void GetCurrentState(State* state) const; 1435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) private: 1455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) static const int kAssociativity = 4; // For hashtable 1465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) static const int kBuckets = 1 << 10; // For hashtable 1475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) static const int kBufferLength = 1 << 18; // For eviction buffer 1485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Type of slots: each slot can be either a count, or a PC value 1505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) typedef uintptr_t Slot; 1515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Hash-table/eviction-buffer entry (a.k.a. a sample) 1535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct Entry { 1545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Slot count; // Number of hits 1555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Slot depth; // Stack depth 1565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Slot stack[kMaxStackDepth]; // Stack contents 1575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }; 1585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Hash table bucket 1605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) struct Bucket { 1615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Entry entry[kAssociativity]; 1625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) }; 1635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Bucket* hash_; // hash table 1655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Slot* evict_; // evicted entries 1665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int num_evicted_; // how many evicted entries? 1675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int out_; // fd for output file. 1685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int count_; // How many samples recorded 1695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int evictions_; // How many evictions 1705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) size_t total_bytes_; // How much output 1715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) char* fname_; // Profile file name 1725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) time_t start_time_; // Start time, or 0 1735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Move 'entry' to the eviction buffer. 1755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void Evict(const Entry& entry); 1765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Write contents of eviction buffer to disk. 1785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) void FlushEvicted(); 1795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DISALLOW_COPY_AND_ASSIGN(ProfileData); 1815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)}; 1825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#endif // BASE_PROFILEDATA_H_ 184