1b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// Use of this source code is governed by a BSD-style license that can be 3b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// found in the LICENSE file. 4b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 5b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/metrics/field_trial.h" 6b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 7b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include <algorithm> 8b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 9b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/build_time.h" 10b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/logging.h" 11b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/rand_util.h" 12b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/strings/string_util.h" 13b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/strings/stringprintf.h" 14b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat#include "base/strings/utf_string_conversions.h" 15b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 16b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratnamespace base { 17b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 18b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratnamespace { 19b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 20cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// Define a separator character to use when creating a persistent form of an 21cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// instance. This is intended for use as a command line argument, passed to a 22cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// second process to mimic our state (i.e., provide the same group name). 23cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkoconst char kPersistentStringSeparator = '/'; // Currently a slash. 24cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 25cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// Define a marker character to be used as a prefix to a trial name on the 26cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// command line which forces its activation. 27cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkoconst char kActivationMarker = '*'; 28cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 29b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// Created a time value based on |year|, |month| and |day_of_month| parameters. 30b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratTime CreateTimeFromParams(int year, int month, int day_of_month) { 31b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GT(year, 1970); 32b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GT(month, 0); 33b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_LT(month, 13); 34b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GT(day_of_month, 0); 35b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_LT(day_of_month, 32); 36b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 37b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat Time::Exploded exploded; 38b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.year = year; 39b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.month = month; 40b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.day_of_week = 0; // Should be unused. 41b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.day_of_month = day_of_month; 42b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.hour = 0; 43b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.minute = 0; 44b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.second = 0; 45b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat exploded.millisecond = 0; 46b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 47b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return Time::FromLocalExploded(exploded); 48b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 49b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 50b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// Returns the boundary value for comparing against the FieldTrial's added 51b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// groups for a given |divisor| (total probability) and |entropy_value|. 52b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial::Probability GetGroupBoundaryValue( 53b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::Probability divisor, 54b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat double entropy_value) { 55b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Add a tiny epsilon value to get consistent results when converting floating 56b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // points to int. Without it, boundary values have inconsistent results, e.g.: 57b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // 58b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // static_cast<FieldTrial::Probability>(100 * 0.56) == 56 59b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // static_cast<FieldTrial::Probability>(100 * 0.57) == 56 60b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // static_cast<FieldTrial::Probability>(100 * 0.58) == 57 61b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // static_cast<FieldTrial::Probability>(100 * 0.59) == 59 62b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const double kEpsilon = 1e-8; 63b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const FieldTrial::Probability result = 64b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat static_cast<FieldTrial::Probability>(divisor * entropy_value + kEpsilon); 65b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Ensure that adding the epsilon still results in a value < |divisor|. 66b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return std::min(result, divisor - 1); 67b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 68b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 69cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// Parses the --force-fieldtrials string |trials_string| into |entries|. 70cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// Returns true if the string was parsed correctly. On failure, the |entries| 71cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// array may end up being partially filled. 72cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkobool ParseFieldTrialsString(const std::string& trials_string, 73cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko std::vector<FieldTrial::State>* entries) { 74cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko const StringPiece trials_string_piece(trials_string); 75cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 76cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko size_t next_item = 0; 77cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko while (next_item < trials_string.length()) { 78cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko size_t name_end = trials_string.find(kPersistentStringSeparator, next_item); 79cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (name_end == trials_string.npos || next_item == name_end) 80cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return false; 81cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko size_t group_name_end = 82cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko trials_string.find(kPersistentStringSeparator, name_end + 1); 83cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (name_end + 1 == group_name_end) 84cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return false; 85cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (group_name_end == trials_string.npos) 86cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko group_name_end = trials_string.length(); 87cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 88cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial::State entry; 89cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko // Verify if the trial should be activated or not. 90cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (trials_string[next_item] == kActivationMarker) { 91cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko // Name cannot be only the indicator. 92cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (name_end - next_item == 1) 93cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return false; 94cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko next_item++; 95cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko entry.activated = true; 96cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko } 97cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko entry.trial_name = 98cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko trials_string_piece.substr(next_item, name_end - next_item); 99cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko entry.group_name = 100cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko trials_string_piece.substr(name_end + 1, group_name_end - name_end - 1); 101cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko next_item = group_name_end + 1; 102cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 103cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko entries->push_back(entry); 104cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko } 105cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return true; 106cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko} 107cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 108b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} // namespace 109b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 110b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// statics 111b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratconst int FieldTrial::kNotFinalized = -1; 112b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratconst int FieldTrial::kDefaultGroupNumber = 0; 113b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratbool FieldTrial::enable_benchmarking_ = false; 114b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 115b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratint FieldTrialList::kNoExpirationYear = 0; 116b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 117b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat//------------------------------------------------------------------------------ 118b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// FieldTrial methods and members. 119b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 120b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial::EntropyProvider::~EntropyProvider() { 121b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 122b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 123cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex VakulenkoFieldTrial::State::State() : activated(false) {} 124cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 125cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex VakulenkoFieldTrial::State::~State() {} 126cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 127b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrial::Disable() { 128b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!group_reported_); 129b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat enable_field_trial_ = false; 130b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 131b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // In case we are disabled after initialization, we need to switch 132b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // the trial to the default group. 133b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (group_ != kNotFinalized) { 134b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Only reset when not already the default group, because in case we were 135b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // forced to the default group, the group number may not be 136b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // kDefaultGroupNumber, so we should keep it as is. 137b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (group_name_ != default_group_name_) 138b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat SetGroupChoice(default_group_name_, kDefaultGroupNumber); 139b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 140b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 141b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 142b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratint FieldTrial::AppendGroup(const std::string& name, 143b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat Probability group_probability) { 144b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // When the group choice was previously forced, we only need to return the 145b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // the id of the chosen group, and anything can be returned for the others. 146b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (forced_) { 147b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!group_name_.empty()); 148b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (name == group_name_) { 149b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Note that while |group_| may be equal to |kDefaultGroupNumber| on the 150b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // forced trial, it will not have the same value as the default group 151b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // number returned from the non-forced |FactoryGetFieldTrial()| call, 152b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // which takes care to ensure that this does not happen. 153b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return group_; 154b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 155b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_NE(next_group_number_, group_); 156b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // We still return different numbers each time, in case some caller need 157b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // them to be different. 158b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return next_group_number_++; 159b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 160b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 161b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_LE(group_probability, divisor_); 162b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GE(group_probability, 0); 163b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 164b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (enable_benchmarking_ || !enable_field_trial_) 165b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat group_probability = 0; 166b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 167b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat accumulated_group_probability_ += group_probability; 168b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 169b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_LE(accumulated_group_probability_, divisor_); 170b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (group_ == kNotFinalized && accumulated_group_probability_ > random_) { 171b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // This is the group that crossed the random line, so we do the assignment. 172b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat SetGroupChoice(name, next_group_number_); 173b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 174b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return next_group_number_++; 175b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 176b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 177b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratint FieldTrial::group() { 178b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FinalizeGroupChoice(); 179b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (trial_registered_) 180b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrialList::NotifyFieldTrialGroupSelection(this); 181b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return group_; 182b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 183b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 184b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratconst std::string& FieldTrial::group_name() { 185b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Call |group()| to ensure group gets assigned and observers are notified. 186b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat group(); 187b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!group_name_.empty()); 188b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return group_name_; 189b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 190b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 191cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkoconst std::string& FieldTrial::GetGroupNameWithoutActivation() { 192cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FinalizeGroupChoice(); 193cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return group_name_; 194cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko} 195cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 196b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrial::SetForced() { 197b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // We might have been forced before (e.g., by CreateFieldTrial) and it's 198b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // first come first served, e.g., command line switch has precedence. 199b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (forced_) 200b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 201b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 202b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // And we must finalize the group choice before we mark ourselves as forced. 203b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FinalizeGroupChoice(); 204b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat forced_ = true; 205b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 206b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 207b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 208b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrial::EnableBenchmarking() { 209b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(0u, FieldTrialList::GetFieldTrialCount()); 210b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat enable_benchmarking_ = true; 211b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 212b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 213b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 214b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial* FieldTrial::CreateSimulatedFieldTrial( 215b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& trial_name, 216b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat Probability total_probability, 217b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& default_group_name, 218b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat double entropy_value) { 219b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return new FieldTrial(trial_name, total_probability, default_group_name, 220b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat entropy_value); 221b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 222b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 223b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial::FieldTrial(const std::string& trial_name, 224b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const Probability total_probability, 225b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& default_group_name, 226b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat double entropy_value) 227b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat : trial_name_(trial_name), 228b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat divisor_(total_probability), 229b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat default_group_name_(default_group_name), 230b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat random_(GetGroupBoundaryValue(total_probability, entropy_value)), 231b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat accumulated_group_probability_(0), 232b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat next_group_number_(kDefaultGroupNumber + 1), 233b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat group_(kNotFinalized), 234b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat enable_field_trial_(true), 235b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat forced_(false), 236b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat group_reported_(false), 237b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial_registered_(false) { 238b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GT(total_probability, 0); 239b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!trial_name_.empty()); 240b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!default_group_name_.empty()); 241b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 242b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 243b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial::~FieldTrial() {} 244b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 245b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrial::SetTrialRegistered() { 246b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(kNotFinalized, group_); 247b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!trial_registered_); 248b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial_registered_ = true; 249b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 250b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 251b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrial::SetGroupChoice(const std::string& group_name, int number) { 252b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat group_ = number; 253b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (group_name.empty()) 254b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat StringAppendF(&group_name_, "%d", group_); 255b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat else 256b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat group_name_ = group_name; 257b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DVLOG(1) << "Field trial: " << trial_name_ << " Group choice:" << group_name_; 258b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 259b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 260b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrial::FinalizeGroupChoice() { 261b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (group_ != kNotFinalized) 262b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 263b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat accumulated_group_probability_ = divisor_; 264b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Here it's OK to use |kDefaultGroupNumber| since we can't be forced and not 265b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // finalized. 266b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!forced_); 267b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat SetGroupChoice(default_group_name_, kDefaultGroupNumber); 268b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 269b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 270b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratbool FieldTrial::GetActiveGroup(ActiveGroup* active_group) const { 271b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!group_reported_ || !enable_field_trial_) 272b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return false; 273b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_NE(group_, kNotFinalized); 274b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat active_group->trial_name = trial_name_; 275b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat active_group->group_name = group_name_; 276b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return true; 277b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 278b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 279cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkobool FieldTrial::GetState(State* field_trial_state) { 280b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!enable_field_trial_) 281b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return false; 282cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FinalizeGroupChoice(); 283b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial_state->trial_name = trial_name_; 284cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko field_trial_state->group_name = group_name_; 285b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial_state->activated = group_reported_; 286b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return true; 287b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 288b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 289b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat//------------------------------------------------------------------------------ 290b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// FieldTrialList methods and members. 291b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 292b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 293b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrialList* FieldTrialList::global_ = NULL; 294b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 295b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 296b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratbool FieldTrialList::used_without_global_ = false; 297b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 298b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrialList::Observer::~Observer() { 299b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 300b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 301b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrialList::FieldTrialList( 302b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const FieldTrial::EntropyProvider* entropy_provider) 303b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat : entropy_provider_(entropy_provider), 304b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat observer_list_(new ObserverListThreadSafe<FieldTrialList::Observer>( 305b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat ObserverListBase<FieldTrialList::Observer>::NOTIFY_EXISTING_ONLY)) { 306b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!global_); 307b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!used_without_global_); 308b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat global_ = this; 309b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 310b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat Time two_years_from_build_time = GetBuildTime() + TimeDelta::FromDays(730); 311b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat Time::Exploded exploded; 312b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat two_years_from_build_time.LocalExplode(&exploded); 313b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat kNoExpirationYear = exploded.year; 314b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 315b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 316b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrialList::~FieldTrialList() { 317b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(lock_); 318b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat while (!registered_.empty()) { 319b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat RegistrationMap::iterator it = registered_.begin(); 320b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat it->second->Release(); 321b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat registered_.erase(it->first); 322b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 323b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(this, global_); 324b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat global_ = NULL; 325b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 326b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 327b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 328b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial* FieldTrialList::FactoryGetFieldTrial( 329b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& trial_name, 330b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::Probability total_probability, 331b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& default_group_name, 332b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int year, 333b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int month, 334b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int day_of_month, 335b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::RandomizationType randomization_type, 336b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat int* default_group_number) { 337b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return FactoryGetFieldTrialWithRandomizationSeed( 338b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial_name, total_probability, default_group_name, 339b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat year, month, day_of_month, randomization_type, 0, default_group_number); 340b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 341b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 342b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 343b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial* FieldTrialList::FactoryGetFieldTrialWithRandomizationSeed( 344b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& trial_name, 345b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::Probability total_probability, 346b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& default_group_name, 347b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int year, 348b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int month, 349b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int day_of_month, 350b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::RandomizationType randomization_type, 351cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko uint32_t randomization_seed, 352b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat int* default_group_number) { 353b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (default_group_number) 354b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat *default_group_number = FieldTrial::kDefaultGroupNumber; 355b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Check if the field trial has already been created in some other way. 356b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial* existing_trial = Find(trial_name); 357b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (existing_trial) { 358b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat CHECK(existing_trial->forced_); 359b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // If the default group name differs between the existing forced trial 360b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // and this trial, then use a different value for the default group number. 361b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (default_group_number && 362b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat default_group_name != existing_trial->default_group_name()) { 363b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // If the new default group number corresponds to the group that was 364b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // chosen for the forced trial (which has been finalized when it was 365b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // forced), then set the default group number to that. 366b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (default_group_name == existing_trial->group_name_internal()) { 367b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat *default_group_number = existing_trial->group_; 368b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } else { 369b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Otherwise, use |kNonConflictingGroupNumber| (-2) for the default 370b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // group number, so that it does not conflict with the |AppendGroup()| 371b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // result for the chosen group. 372b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int kNonConflictingGroupNumber = -2; 373cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko static_assert( 374b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat kNonConflictingGroupNumber != FieldTrial::kDefaultGroupNumber, 375cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko "The 'non-conflicting' group number conflicts"); 376cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko static_assert(kNonConflictingGroupNumber != FieldTrial::kNotFinalized, 377cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko "The 'non-conflicting' group number conflicts"); 378b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat *default_group_number = kNonConflictingGroupNumber; 379b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 380b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 381b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return existing_trial; 382b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 383b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 384b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat double entropy_value; 385b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (randomization_type == FieldTrial::ONE_TIME_RANDOMIZED) { 386b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const FieldTrial::EntropyProvider* entropy_provider = 387b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat GetEntropyProviderForOneTimeRandomization(); 388b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat CHECK(entropy_provider); 389b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat entropy_value = entropy_provider->GetEntropyForTrial(trial_name, 390b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat randomization_seed); 391b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } else { 392b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(FieldTrial::SESSION_RANDOMIZED, randomization_type); 393b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(0U, randomization_seed); 394b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat entropy_value = RandDouble(); 395b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 396b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 397b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial* field_trial = new FieldTrial(trial_name, total_probability, 398b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat default_group_name, entropy_value); 399b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (GetBuildTime() > CreateTimeFromParams(year, month, day_of_month)) 400b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial->Disable(); 401b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrialList::Register(field_trial); 402b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return field_trial; 403b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 404b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 405b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 406cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex VakulenkoFieldTrial* FieldTrialList::Find(const std::string& trial_name) { 407b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 408b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return NULL; 409b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(global_->lock_); 410cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return global_->PreLockedFind(trial_name); 411b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 412b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 413b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 414cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkoint FieldTrialList::FindValue(const std::string& trial_name) { 415cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial* field_trial = Find(trial_name); 416b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (field_trial) 417b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return field_trial->group(); 418b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return FieldTrial::kNotFinalized; 419b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 420b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 421b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 422cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkostd::string FieldTrialList::FindFullName(const std::string& trial_name) { 423cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial* field_trial = Find(trial_name); 424b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (field_trial) 425b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return field_trial->group_name(); 426b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return std::string(); 427b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 428b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 429b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 430cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkobool FieldTrialList::TrialExists(const std::string& trial_name) { 431cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return Find(trial_name) != NULL; 432cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko} 433cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 434cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// static 435cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkobool FieldTrialList::IsTrialActive(const std::string& trial_name) { 436cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial* field_trial = Find(trial_name); 437cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial::ActiveGroup active_group; 438cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return field_trial && field_trial->GetActiveGroup(&active_group); 439b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 440b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 441b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 442b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::StatesToString(std::string* output) { 443b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::ActiveGroups active_groups; 444b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat GetActiveFieldTrialGroups(&active_groups); 445b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat for (FieldTrial::ActiveGroups::const_iterator it = active_groups.begin(); 446b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat it != active_groups.end(); ++it) { 447b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(std::string::npos, 448b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat it->trial_name.find(kPersistentStringSeparator)); 449b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(std::string::npos, 450b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat it->group_name.find(kPersistentStringSeparator)); 451b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(it->trial_name); 452b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(1, kPersistentStringSeparator); 453b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(it->group_name); 454b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(1, kPersistentStringSeparator); 455b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 456b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 457b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 458b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 459b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::AllStatesToString(std::string* output) { 460b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 461b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 462b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(global_->lock_); 463b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 464b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat for (const auto& registered : global_->registered_) { 465cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial::State trial; 466b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!registered.second->GetState(&trial)) 467b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat continue; 468b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(std::string::npos, 469b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial.trial_name.find(kPersistentStringSeparator)); 470b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_EQ(std::string::npos, 471b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial.group_name.find(kPersistentStringSeparator)); 472b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (trial.activated) 473b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(1, kActivationMarker); 474cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko trial.trial_name.AppendToString(output); 475b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(1, kPersistentStringSeparator); 476cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko trial.group_name.AppendToString(output); 477b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat output->append(1, kPersistentStringSeparator); 478b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 479b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 480b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 481b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 482b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::GetActiveFieldTrialGroups( 483b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::ActiveGroups* active_groups) { 484b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(active_groups->empty()); 485b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 486b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 487b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(global_->lock_); 488b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 489b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat for (RegistrationMap::iterator it = global_->registered_.begin(); 490b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat it != global_->registered_.end(); ++it) { 491b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial::ActiveGroup active_group; 492b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (it->second->GetActiveGroup(&active_group)) 493b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat active_groups->push_back(active_group); 494b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 495b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 496b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 497b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 498cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenkovoid FieldTrialList::GetActiveFieldTrialGroupsFromString( 499cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko const std::string& trials_string, 500cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial::ActiveGroups* active_groups) { 501cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko std::vector<FieldTrial::State> entries; 502cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (!ParseFieldTrialsString(trials_string, &entries)) 503cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return; 504cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 505cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko for (const auto& entry : entries) { 506cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (entry.activated) { 507cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial::ActiveGroup group; 508cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko group.trial_name = entry.trial_name.as_string(); 509cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko group.group_name = entry.group_name.as_string(); 510cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko active_groups->push_back(group); 511cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko } 512cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko } 513cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko} 514cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko 515cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko// static 516b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratbool FieldTrialList::CreateTrialsFromString( 517b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& trials_string, 518b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrialActivationMode mode, 519b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::set<std::string>& ignored_trial_names) { 520b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(global_); 521b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (trials_string.empty() || !global_) 522b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return true; 523b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 524cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko std::vector<FieldTrial::State> entries; 525cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (!ParseFieldTrialsString(trials_string, &entries)) 526cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko return false; 527b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 528cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko for (const auto& entry : entries) { 529cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko const std::string trial_name = entry.trial_name.as_string(); 530cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko const std::string group_name = entry.group_name.as_string(); 531b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 532cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (ContainsKey(ignored_trial_names, trial_name)) 533b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat continue; 534b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 535cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko FieldTrial* trial = CreateFieldTrial(trial_name, group_name); 536b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!trial) 537b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return false; 538cce46a0c214b37e8da48c522c83037e8ffa4f9fdAlex Vakulenko if (mode == ACTIVATE_TRIALS || entry.activated) { 539b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Call |group()| to mark the trial as "used" and notify observers, if 540b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // any. This is useful to ensure that field trials created in child 541b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // processes are properly reported in crash reports. 542b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial->group(); 543b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 544b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 545b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return true; 546b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 547b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 548b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 549b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial* FieldTrialList::CreateFieldTrial( 550b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& name, 551b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const std::string& group_name) { 552b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(global_); 553b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GE(name.size(), 0u); 554b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK_GE(group_name.size(), 0u); 555b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (name.empty() || group_name.empty() || !global_) 556b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return NULL; 557b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 558b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrial* field_trial = FieldTrialList::Find(name); 559b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (field_trial) { 560b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // In single process mode, or when we force them from the command line, 561b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // we may have already created the field trial. 562b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (field_trial->group_name_internal() != group_name) 563b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return NULL; 564b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return field_trial; 565b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 566b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat const int kTotalProbability = 100; 567b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial = new FieldTrial(name, kTotalProbability, group_name, 0); 568b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrialList::Register(field_trial); 569b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat // Force the trial, which will also finalize the group choice. 570b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial->SetForced(); 571b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return field_trial; 572b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 573b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 574b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 575b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::AddObserver(Observer* observer) { 576b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 577b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 578b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat global_->observer_list_->AddObserver(observer); 579b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 580b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 581b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 582b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::RemoveObserver(Observer* observer) { 583b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 584b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 585b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat global_->observer_list_->RemoveObserver(observer); 586b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 587b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 588b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 589b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::NotifyFieldTrialGroupSelection(FieldTrial* field_trial) { 590b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 591b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 592b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 593b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat { 594b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(global_->lock_); 595b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (field_trial->group_reported_) 596b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 597b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial->group_reported_ = true; 598b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 599b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 600b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!field_trial->enable_field_trial_) 601b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 602b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 603b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat global_->observer_list_->Notify( 604b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FROM_HERE, &FieldTrialList::Observer::OnFieldTrialGroupFinalized, 605b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat field_trial->trial_name(), field_trial->group_name_internal()); 606b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 607b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 608b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 609b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratsize_t FieldTrialList::GetFieldTrialCount() { 610b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) 611b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return 0; 612b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(global_->lock_); 613b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return global_->registered_.size(); 614b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 615b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 616b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 617b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratconst FieldTrial::EntropyProvider* 618b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat FieldTrialList::GetEntropyProviderForOneTimeRandomization() { 619b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) { 620b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat used_without_global_ = true; 621b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return NULL; 622b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 623b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 624b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return global_->entropy_provider_.get(); 625b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 626b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 627b8cf94937c52feb53b55c39e3f82094d27de464cDaniel EratFieldTrial* FieldTrialList::PreLockedFind(const std::string& name) { 628b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat RegistrationMap::iterator it = registered_.find(name); 629b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (registered_.end() == it) 630b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return NULL; 631b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return it->second; 632b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 633b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 634b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat// static 635b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Eratvoid FieldTrialList::Register(FieldTrial* trial) { 636b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat if (!global_) { 637b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat used_without_global_ = true; 638b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat return; 639b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat } 640b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat AutoLock auto_lock(global_->lock_); 641b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat DCHECK(!global_->PreLockedFind(trial->trial_name())); 642b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial->AddRef(); 643b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat trial->SetTrialRegistered(); 644b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat global_->registered_[trial->trial_name()] = trial; 645b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} 646b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat 647b8cf94937c52feb53b55c39e3f82094d27de464cDaniel Erat} // namespace base 648