field_trial.cc revision d3868032626d59662ff73b372b5d584c1d144c53
15821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Copyright (c) 2012 The Chromium Authors. All rights reserved. 25821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// found in the LICENSE file. 45821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 55821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/metrics/field_trial.h" 65821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 75821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/build_time.h" 85821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/logging.h" 95821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/rand_util.h" 105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/sha1.h" 11868fa2fe829687343ffae624259930155e16dbd8Torne (Richard Coles)#include "base/strings/string_util.h" 12868fa2fe829687343ffae624259930155e16dbd8Torne (Richard Coles)#include "base/strings/stringprintf.h" 13868fa2fe829687343ffae624259930155e16dbd8Torne (Richard Coles)#include "base/strings/utf_string_conversions.h" 145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)#include "base/sys_byteorder.h" 155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace base { 175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)namespace { 195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// Created a time value based on |year|, |month| and |day_of_month| parameters. 215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)Time CreateTimeFromParams(int year, int month, int day_of_month) { 225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GT(year, 1970); 235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GT(month, 0); 245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_LT(month, 13); 255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GT(day_of_month, 0); 265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_LT(day_of_month, 32); 275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Time::Exploded exploded; 295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.year = year; 305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.month = month; 315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.day_of_week = 0; // Should be unused. 325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.day_of_month = day_of_month; 335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.hour = 0; 345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.minute = 0; 355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.second = 0; 365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) exploded.millisecond = 0; 375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return Time::FromLocalExploded(exploded); 395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace 425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)static const char kHistogramFieldTrialSeparator('_'); 445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// statics 465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)const int FieldTrial::kNotFinalized = -1; 475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)const int FieldTrial::kDefaultGroupNumber = 0; 485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)bool FieldTrial::enable_benchmarking_ = false; 495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)const char FieldTrialList::kPersistentStringSeparator('/'); 512a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)int FieldTrialList::kNoExpirationYear = 0; 525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)//------------------------------------------------------------------------------ 545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// FieldTrial methods and members. 555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 562a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)FieldTrial::FieldTrial(const std::string& trial_name, 575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const Probability total_probability, 58d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const std::string& default_group_name, 59d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch double entropy_value) 602a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) : trial_name_(trial_name), 615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) divisor_(total_probability), 625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) default_group_name_(default_group_name), 63d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch random_(static_cast<Probability>(divisor_ * entropy_value)), 645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) accumulated_group_probability_(0), 655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) next_group_number_(kDefaultGroupNumber + 1), 665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) group_(kNotFinalized), 675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) enable_field_trial_(true), 685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) forced_(false), 695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) group_reported_(false) { 705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GT(total_probability, 0); 712a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DCHECK(!trial_name_.empty()); 725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!default_group_name_.empty()); 735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrial::EntropyProvider::~EntropyProvider() { 765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrial::Disable() { 795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!group_reported_); 805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) enable_field_trial_ = false; 815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // In case we are disabled after initialization, we need to switch 835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // the trial to the default group. 845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (group_ != kNotFinalized) { 855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Only reset when not already the default group, because in case we were 865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // forced to the default group, the group number may not be 875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // kDefaultGroupNumber, so we should keep it as is. 885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (group_name_ != default_group_name_) 895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) SetGroupChoice(default_group_name_, kDefaultGroupNumber); 905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)int FieldTrial::AppendGroup(const std::string& name, 945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Probability group_probability) { 955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // When the group choice was previously forced, we only need to return the 965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // the id of the chosen group, and anything can be returned for the others. 975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (forced_) { 985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!group_name_.empty()); 995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (name == group_name_) { 1002a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // Note that while |group_| may be equal to |kDefaultGroupNumber| on the 1012a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // forced trial, it will not have the same value as the default group 1022a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // number returned from the non-forced |FactoryGetFieldTrial()| call, 1032a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // which takes care to ensure that this does not happen. 1045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return group_; 1055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_NE(next_group_number_, group_); 1075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // We still return different numbers each time, in case some caller need 1085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // them to be different. 1095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return next_group_number_++; 1105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_LE(group_probability, divisor_); 1135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GE(group_probability, 0); 1145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (enable_benchmarking_ || !enable_field_trial_) 1165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) group_probability = 0; 1175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) accumulated_group_probability_ += group_probability; 1195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_LE(accumulated_group_probability_, divisor_); 1215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (group_ == kNotFinalized && accumulated_group_probability_ > random_) { 1225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // This is the group that crossed the random line, so we do the assignment. 1235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) SetGroupChoice(name, next_group_number_); 1245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 1255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return next_group_number_++; 1265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)int FieldTrial::group() { 1295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FinalizeGroupChoice(); 1302a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) FieldTrialList::NotifyFieldTrialGroupSelection(this); 1315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return group_; 1325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1342a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)const std::string& FieldTrial::group_name() { 1355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Call |group()| to ensure group gets assigned and observers are notified. 1365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) group(); 1375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!group_name_.empty()); 1385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return group_name_; 1395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 1425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)std::string FieldTrial::MakeName(const std::string& name_prefix, 1435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const std::string& trial_name) { 1445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) std::string big_string(name_prefix); 1455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) big_string.append(1, kHistogramFieldTrialSeparator); 1465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return big_string.append(FieldTrialList::FindFullName(trial_name)); 1475821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 1505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrial::EnableBenchmarking() { 1515821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_EQ(0u, FieldTrialList::GetFieldTrialCount()); 1525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) enable_benchmarking_ = true; 1535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrial::SetForced() { 1565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // We might have been forced before (e.g., by CreateFieldTrial) and it's 1575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // first come first served, e.g., command line switch has precedence. 1585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (forced_) 1595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 1605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // And we must finalize the group choice before we mark ourselves as forced. 1625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FinalizeGroupChoice(); 1635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) forced_ = true; 1645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrial::~FieldTrial() {} 1675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1682a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)void FieldTrial::SetGroupChoice(const std::string& group_name, int number) { 1695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) group_ = number; 1702a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (group_name.empty()) 1715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) StringAppendF(&group_name_, "%d", group_); 1725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) else 1732a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) group_name_ = group_name; 1742a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DVLOG(1) << "Field trial: " << trial_name_ << " Group choice:" << group_name_; 1755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrial::FinalizeGroupChoice() { 1785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (group_ != kNotFinalized) 1795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 1805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) accumulated_group_probability_ = divisor_; 1815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Here it's OK to use |kDefaultGroupNumber| since we can't be forced and not 1825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // finalized. 1835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!forced_); 1845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) SetGroupChoice(default_group_name_, kDefaultGroupNumber); 1855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)bool FieldTrial::GetActiveGroup(ActiveGroup* active_group) const { 1885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!group_reported_ || !enable_field_trial_) 1895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return false; 1905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_NE(group_, kNotFinalized); 1912a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) active_group->trial_name = trial_name_; 1922a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) active_group->group_name = group_name_; 1935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return true; 1945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 1955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)//------------------------------------------------------------------------------ 1975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// FieldTrialList methods and members. 1985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 1995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 2005821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrialList* FieldTrialList::global_ = NULL; 2015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 2035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)bool FieldTrialList::used_without_global_ = false; 2045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrialList::Observer::~Observer() { 2065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrialList::FieldTrialList( 2095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const FieldTrial::EntropyProvider* entropy_provider) 2105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) : entropy_provider_(entropy_provider), 2115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) observer_list_(new ObserverListThreadSafe<FieldTrialList::Observer>( 2125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) ObserverListBase<FieldTrialList::Observer>::NOTIFY_EXISTING_ONLY)) { 2135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!global_); 2145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(!used_without_global_); 2155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) global_ = this; 2165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2172a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) Time two_years_from_build_time = GetBuildTime() + TimeDelta::FromDays(730); 2185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) Time::Exploded exploded; 2192a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) two_years_from_build_time.LocalExplode(&exploded); 2202a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) kNoExpirationYear = exploded.year; 2215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrialList::~FieldTrialList() { 2245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) AutoLock auto_lock(lock_); 2255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while (!registered_.empty()) { 2265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) RegistrationList::iterator it = registered_.begin(); 2275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) it->second->Release(); 2285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) registered_.erase(it->first); 2295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_EQ(this, global_); 2315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) global_ = NULL; 2325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 2335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 2345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 2355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrial* FieldTrialList::FactoryGetFieldTrial( 236d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const std::string& trial_name, 2375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial::Probability total_probability, 2385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const std::string& default_group_name, 2395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const int year, 2405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const int month, 2415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const int day_of_month, 242d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch FieldTrial::RandomizationType randomization_type, 243d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch int* default_group_number) { 244d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch return FactoryGetFieldTrialWithRandomizationSeed( 245d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch trial_name, total_probability, default_group_name, 246d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch year, month, day_of_month, randomization_type, 0, default_group_number); 247d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch} 248d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch 249d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch// static 250d3868032626d59662ff73b372b5d584c1d144c53Ben MurdochFieldTrial* FieldTrialList::FactoryGetFieldTrialWithRandomizationSeed( 251d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const std::string& trial_name, 252d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch FieldTrial::Probability total_probability, 253d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const std::string& default_group_name, 254d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const int year, 255d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const int month, 256d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch const int day_of_month, 257d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch FieldTrial::RandomizationType randomization_type, 258d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch uint32 randomization_seed, 2595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) int* default_group_number) { 2605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (default_group_number) 2615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) *default_group_number = FieldTrial::kDefaultGroupNumber; 2625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // Check if the field trial has already been created in some other way. 263d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch FieldTrial* existing_trial = Find(trial_name); 2645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (existing_trial) { 2655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) CHECK(existing_trial->forced_); 2662a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // If the default group name differs between the existing forced trial 2672a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // and this trial, then use a different value for the default group number. 2685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (default_group_number && 2692a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) default_group_name != existing_trial->default_group_name()) { 2702a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // If the new default group number corresponds to the group that was 2712a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // chosen for the forced trial (which has been finalized when it was 2722a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // forced), then set the default group number to that. 2732a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (default_group_name == existing_trial->group_name_internal()) { 2742a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) *default_group_number = existing_trial->group_; 2752a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } else { 2762a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // Otherwise, use |kNonConflictingGroupNumber| (-2) for the default 2772a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // group number, so that it does not conflict with the |AppendGroup()| 2782a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // result for the chosen group. 2792a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) const int kNonConflictingGroupNumber = -2; 2802a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) COMPILE_ASSERT( 2812a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) kNonConflictingGroupNumber != FieldTrial::kDefaultGroupNumber, 2822a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) conflicting_default_group_number); 2832a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) COMPILE_ASSERT( 2842a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) kNonConflictingGroupNumber != FieldTrial::kNotFinalized, 2852a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) conflicting_default_group_number); 2862a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) *default_group_number = kNonConflictingGroupNumber; 2872a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 2885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return existing_trial; 2905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 2915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 292d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch double entropy_value; 293d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch if (randomization_type == FieldTrial::ONE_TIME_RANDOMIZED) { 294d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch entropy_value = GetEntropyProviderForOneTimeRandomization()-> 295d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch GetEntropyForTrial(trial_name, randomization_seed); 296d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch } else { 297d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch DCHECK_EQ(FieldTrial::SESSION_RANDOMIZED, randomization_type); 298d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch DCHECK_EQ(0U, randomization_seed); 299d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch entropy_value = RandDouble(); 300d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch } 301d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch 302d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch FieldTrial* field_trial = new FieldTrial(trial_name, total_probability, 303d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch default_group_name, entropy_value); 3045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (GetBuildTime() > CreateTimeFromParams(year, month, day_of_month)) 3055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) field_trial->Disable(); 3065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrialList::Register(field_trial); 3075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return field_trial; 3085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 3115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrial* FieldTrialList::Find(const std::string& name) { 3125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) 3135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return NULL; 3145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) AutoLock auto_lock(global_->lock_); 3155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return global_->PreLockedFind(name); 3165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 3195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)int FieldTrialList::FindValue(const std::string& name) { 3205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial* field_trial = Find(name); 3215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (field_trial) 3225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return field_trial->group(); 3235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return FieldTrial::kNotFinalized; 3245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3255821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3265821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 3275821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)std::string FieldTrialList::FindFullName(const std::string& name) { 3285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial* field_trial = Find(name); 3295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (field_trial) 3305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return field_trial->group_name(); 331c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) return std::string(); 3325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 3355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)bool FieldTrialList::TrialExists(const std::string& name) { 3365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return Find(name) != NULL; 3375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 3405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrialList::StatesToString(std::string* output) { 3415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial::ActiveGroups active_groups; 3425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) GetActiveFieldTrialGroups(&active_groups); 3435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (FieldTrial::ActiveGroups::const_iterator it = active_groups.begin(); 3445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) it != active_groups.end(); ++it) { 3452a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DCHECK_EQ(std::string::npos, 3462a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) it->trial_name.find(kPersistentStringSeparator)); 3472a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DCHECK_EQ(std::string::npos, 3482a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) it->group_name.find(kPersistentStringSeparator)); 3492a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) output->append(it->trial_name); 3505821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) output->append(1, kPersistentStringSeparator); 3512a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) output->append(it->group_name); 3525821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) output->append(1, kPersistentStringSeparator); 3535821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3545821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3555821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3565821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 3575821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrialList::GetActiveFieldTrialGroups( 3585821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial::ActiveGroups* active_groups) { 3595821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(active_groups->empty()); 3605821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) 3615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 3625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) AutoLock auto_lock(global_->lock_); 3635821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3645821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) for (RegistrationList::iterator it = global_->registered_.begin(); 3655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) it != global_->registered_.end(); ++it) { 3665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial::ActiveGroup active_group; 3675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (it->second->GetActiveGroup(&active_group)) 3685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) active_groups->push_back(active_group); 3695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 3705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 3715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 373eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdochbool FieldTrialList::CreateTrialsFromString(const std::string& trials_string, 374eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch FieldTrialActivationMode mode) { 3755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(global_); 3765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (trials_string.empty() || !global_) 3775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return true; 3785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) size_t next_item = 0; 3805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) while (next_item < trials_string.length()) { 3815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) size_t name_end = trials_string.find(kPersistentStringSeparator, next_item); 3825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (name_end == trials_string.npos || next_item == name_end) 3835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return false; 3845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) size_t group_name_end = trials_string.find(kPersistentStringSeparator, 3855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) name_end + 1); 3865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (group_name_end == trials_string.npos || name_end + 1 == group_name_end) 3875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return false; 3885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) std::string name(trials_string, next_item, name_end - next_item); 3895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) std::string group_name(trials_string, name_end + 1, 3905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) group_name_end - name_end - 1); 3915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) next_item = group_name_end + 1; 3925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 3932a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) FieldTrial* trial = CreateFieldTrial(name, group_name); 3942a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (!trial) 3955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return false; 396eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch if (mode == ACTIVATE_TRIALS) { 397eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch // Call |group()| to mark the trial as "used" and notify observers, if 398eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch // any. This is useful to ensure that field trials created in child 399eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch // processes are properly reported in crash reports. 400eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch trial->group(); 401eb525c5499e34cc9c4b825d6d9e75bb07cc06aceBen Murdoch } 4025821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 4035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return true; 4045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4065821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4075821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrial* FieldTrialList::CreateFieldTrial( 4085821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const std::string& name, 4095821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const std::string& group_name) { 4105821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK(global_); 4115821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GE(name.size(), 0u); 4125821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) DCHECK_GE(group_name.size(), 0u); 4135821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (name.empty() || group_name.empty() || !global_) 4145821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return NULL; 4155821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4165821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrial* field_trial = FieldTrialList::Find(name); 4175821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (field_trial) { 4185821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // In single process mode, or when we force them from the command line, 4195821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) // we may have already created the field trial. 4205821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (field_trial->group_name_internal() != group_name) 4215821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return NULL; 4225821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return field_trial; 4235821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 4245821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) const int kTotalProbability = 100; 425d3868032626d59662ff73b372b5d584c1d144c53Ben Murdoch field_trial = new FieldTrial(name, kTotalProbability, group_name, 0); 4262a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) // Force the trial, which will also finalize the group choice. 4272a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) field_trial->SetForced(); 4285821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrialList::Register(field_trial); 4295821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return field_trial; 4305821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4315821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4325821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4335821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrialList::AddObserver(Observer* observer) { 4345821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) 4355821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 4365821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) global_->observer_list_->AddObserver(observer); 4375821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4385821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4395821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4405821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrialList::RemoveObserver(Observer* observer) { 4415821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) 4425821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 4435821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) global_->observer_list_->RemoveObserver(observer); 4445821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4455821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4465821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4472a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles)void FieldTrialList::NotifyFieldTrialGroupSelection(FieldTrial* field_trial) { 4485821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) 4495821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 4502a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 4512a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) { 4522a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) AutoLock auto_lock(global_->lock_); 4532a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (field_trial->group_reported_) 4542a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 4552a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) field_trial->group_reported_ = true; 4562a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) } 4572a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 4582a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) if (!field_trial->enable_field_trial_) 4592a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) return; 4602a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) 4615821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) global_->observer_list_->Notify( 4625821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) &FieldTrialList::Observer::OnFieldTrialGroupFinalized, 4632a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) field_trial->trial_name(), 4642a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) field_trial->group_name_internal()); 4655821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4665821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4675821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4685821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)size_t FieldTrialList::GetFieldTrialCount() { 4695821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) 4705821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return 0; 4715821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) AutoLock auto_lock(global_->lock_); 4725821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return global_->registered_.size(); 4735821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4745821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4755821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4765821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)const FieldTrial::EntropyProvider* 4775821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) FieldTrialList::GetEntropyProviderForOneTimeRandomization() { 4785821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) { 4795821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) used_without_global_ = true; 4805821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return NULL; 4815821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 4825821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4835821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return global_->entropy_provider_.get(); 4845821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4855821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4865821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)FieldTrial* FieldTrialList::PreLockedFind(const std::string& name) { 4875821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) RegistrationList::iterator it = registered_.find(name); 4885821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (registered_.end() == it) 4895821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return NULL; 4905821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return it->second; 4915821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 4925821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 4935821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)// static 4945821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)void FieldTrialList::Register(FieldTrial* trial) { 4955821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) if (!global_) { 4965821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) used_without_global_ = true; 4975821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) return; 4985821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) } 4995821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) AutoLock auto_lock(global_->lock_); 5002a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) DCHECK(!global_->PreLockedFind(trial->trial_name())); 5015821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) trial->AddRef(); 5022a99a7e74a7f215066514fe81d2bfa6639d9edddTorne (Richard Coles) global_->registered_[trial->trial_name()] = trial; 5035821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} 5045821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles) 5055821806d5e7f356e8fa4b058a389a808ea183019Torne (Richard Coles)} // namespace base 506