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base / system / sys_info.cc [blame]
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/system/sys_info.h"
#include <algorithm>
#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/features.h"
#include "base/functional/bind.h"
#include "base/functional/callback.h"
#include "base/location.h"
#include "base/notreached.h"
#include "base/system/sys_info_internal.h"
#include "base/task/task_traits.h"
#include "base/task/thread_pool.h"
#include "base/time/time.h"
#include "build/build_config.h"
namespace base {
namespace {
uint64_t GetLowMemoryDeviceThresholdMB() {
static const uint64_t threshold = base::saturated_cast<uint64_t>(
features::kLowMemoryDeviceThresholdMB.Get());
return threshold;
}
std::optional<uint64_t> g_amount_of_physical_memory_mb_for_testing;
} // namespace
// static
int SysInfo::NumberOfEfficientProcessors() {
static int number_of_efficient_processors = NumberOfEfficientProcessorsImpl();
return number_of_efficient_processors;
}
// static
uint64_t SysInfo::AmountOfPhysicalMemory() {
constexpr uint64_t kMB = 1024 * 1024;
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kEnableLowEndDeviceMode)) {
// Keep using 512MB as the simulated RAM amount for when users or tests have
// manually enabled low-end device mode. Note this value is different from
// the threshold used for low end devices.
constexpr uint64_t kSimulatedMemoryForEnableLowEndDeviceMode = 512 * kMB;
return std::min(kSimulatedMemoryForEnableLowEndDeviceMode,
AmountOfPhysicalMemoryImpl());
}
if (g_amount_of_physical_memory_mb_for_testing) {
return g_amount_of_physical_memory_mb_for_testing.value() * kMB;
}
return AmountOfPhysicalMemoryImpl();
}
// static
uint64_t SysInfo::AmountOfAvailablePhysicalMemory() {
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kEnableLowEndDeviceMode)) {
// Estimate the available memory by subtracting our memory used estimate
// from the fake |kLowMemoryDeviceThresholdMB| limit.
uint64_t memory_used =
AmountOfPhysicalMemoryImpl() - AmountOfAvailablePhysicalMemoryImpl();
uint64_t memory_limit = GetLowMemoryDeviceThresholdMB() * 1024 * 1024;
// std::min ensures no underflow, as |memory_used| can be > |memory_limit|.
return memory_limit - std::min(memory_used, memory_limit);
}
return AmountOfAvailablePhysicalMemoryImpl();
}
bool SysInfo::IsLowEndDevice() {
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kEnableLowEndDeviceMode)) {
return true;
}
return IsLowEndDeviceImpl();
}
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS)
namespace {
enum class BucketizedSize {
k2GbOrLess,
k3Gb,
k4Gb,
k6Gb,
k8GbOrHigher,
};
BucketizedSize GetSystemRamBucketizedSize() {
int physical_memory = base::SysInfo::AmountOfPhysicalMemoryMB();
// Because of Android carveouts, AmountOfPhysicalMemory() returns smaller
// than the actual memory size, So we will use a small lowerbound than "X"GB
// to discriminate real "X"GB devices from lower memory ones.
// Addendum: This logic should also work for ChromeOS.
constexpr int kUpperBound2GB = 2 * 1024; // inclusive
if (physical_memory <= kUpperBound2GB) {
return BucketizedSize::k2GbOrLess;
}
constexpr int kLowerBound3GB = kUpperBound2GB; // exclusive
constexpr int kUpperBound3GB = 3.2 * 1024; // inclusive
if (kLowerBound3GB < physical_memory && physical_memory <= kUpperBound3GB) {
return BucketizedSize::k3Gb;
}
constexpr int kLowerBound4GB = kUpperBound3GB; // exclusive
constexpr int kUpperBound4GB = 4 * 1024; // inclusive
if (kLowerBound4GB < physical_memory && physical_memory <= kUpperBound4GB) {
return BucketizedSize::k4Gb;
}
constexpr int kLowerBound6GB = kUpperBound4GB; // exclusive
constexpr int kUpperBound6GB = 6.5 * 1024 - 1; // inclusive
if (kLowerBound6GB < physical_memory && physical_memory <= kUpperBound6GB) {
return BucketizedSize::k6Gb;
}
return BucketizedSize::k8GbOrHigher;
}
BucketizedSize GetCachedSystemRamBucketizedSize() {
static BucketizedSize s_size = GetSystemRamBucketizedSize();
return s_size;
}
bool IsPartialLowEndModeOnMidRangeDevicesEnabled() {
// TODO(crbug.com/40264947): make the feature not enable on 32-bit devices
// before launching or going to high Stable %.
return SysInfo::Is4GbOr6GbDevice() &&
base::FeatureList::IsEnabled(
features::kPartialLowEndModeOnMidRangeDevices);
}
bool IsPartialLowEndModeOn3GbDevicesEnabled() {
return SysInfo::Is3GbDevice() &&
base::FeatureList::IsEnabled(features::kPartialLowEndModeOn3GbDevices);
}
} // namespace
bool SysInfo::Is3GbDevice() {
return GetCachedSystemRamBucketizedSize() == BucketizedSize::k3Gb;
}
bool SysInfo::Is4GbDevice() {
return GetCachedSystemRamBucketizedSize() == BucketizedSize::k4Gb;
}
bool SysInfo::Is4GbOr6GbDevice() {
return GetCachedSystemRamBucketizedSize() == BucketizedSize::k4Gb ||
GetCachedSystemRamBucketizedSize() == BucketizedSize::k6Gb;
}
bool SysInfo::Is6GbDevice() {
return GetCachedSystemRamBucketizedSize() == BucketizedSize::k6Gb;
}
#endif // BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS)
// TODO(crbug.com/40264947): This method is for chromium native code.
// We need to update the java-side code, i.e.
// base/android/java/src/org/chromium/base/SysUtils.java,
// and to make the selected components in java to see this feature.
bool SysInfo::IsLowEndDeviceOrPartialLowEndModeEnabled() {
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS)
return base::SysInfo::IsLowEndDevice() ||
IsPartialLowEndModeOnMidRangeDevicesEnabled() ||
IsPartialLowEndModeOn3GbDevicesEnabled();
#else
return base::SysInfo::IsLowEndDevice();
#endif
}
bool SysInfo::IsLowEndDeviceOrPartialLowEndModeEnabled(
const FeatureParam<bool>& param_for_exclusion) {
#if BUILDFLAG(IS_ANDROID) || BUILDFLAG(IS_CHROMEOS)
return base::SysInfo::IsLowEndDevice() ||
((IsPartialLowEndModeOnMidRangeDevicesEnabled() ||
IsPartialLowEndModeOn3GbDevicesEnabled()) &&
!param_for_exclusion.Get());
#else
return base::SysInfo::IsLowEndDevice();
#endif
}
#if !BUILDFLAG(IS_ANDROID)
// The Android equivalent of this lives in `detectLowEndDevice()` at:
// base/android/java/src/org/chromium/base/SysUtils.java
bool DetectLowEndDevice() {
CommandLine* command_line = CommandLine::ForCurrentProcess();
if (command_line->HasSwitch(switches::kEnableLowEndDeviceMode))
return true;
if (command_line->HasSwitch(switches::kDisableLowEndDeviceMode))
return false;
int ram_size_mb = SysInfo::AmountOfPhysicalMemoryMB();
return ram_size_mb > 0 &&
static_cast<uint64_t>(ram_size_mb) <= GetLowMemoryDeviceThresholdMB();
}
// static
bool SysInfo::IsLowEndDeviceImpl() {
static internal::LazySysInfoValue<bool, DetectLowEndDevice> instance;
return instance.value();
}
#endif
#if !BUILDFLAG(IS_APPLE) && !BUILDFLAG(IS_ANDROID) && !BUILDFLAG(IS_WIN) && \
!BUILDFLAG(IS_CHROMEOS)
std::string SysInfo::HardwareModelName() {
return std::string();
}
#endif
#if !BUILDFLAG(IS_ANDROID)
std::string SysInfo::SocManufacturer() {
return std::string();
}
#endif
void SysInfo::GetHardwareInfo(base::OnceCallback<void(HardwareInfo)> callback) {
#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_FUCHSIA)
constexpr base::TaskTraits kTraits = {base::MayBlock()};
#else
constexpr base::TaskTraits kTraits = {};
#endif
base::ThreadPool::PostTaskAndReplyWithResult(
FROM_HERE, kTraits, base::BindOnce(&GetHardwareInfoSync),
std::move(callback));
}
// static
base::TimeDelta SysInfo::Uptime() {
// This code relies on an implementation detail of TimeTicks::Now() - that
// its return value happens to coincide with the system uptime value in
// microseconds, on Win/Mac/iOS/Linux/ChromeOS and Android.
int64_t uptime_in_microseconds = TimeTicks::Now().ToInternalValue();
return base::Microseconds(uptime_in_microseconds);
}
// static
std::string SysInfo::ProcessCPUArchitecture() {
#if defined(ARCH_CPU_X86)
return "x86";
#elif defined(ARCH_CPU_X86_64)
return "x86_64";
#elif defined(ARCH_CPU_ARMEL)
return "ARM";
#elif defined(ARCH_CPU_ARM64)
return "ARM_64";
#elif defined(ARCH_CPU_RISCV64)
return "RISCV_64";
#else
return std::string();
#endif
}
// static
std::optional<uint64_t> SysInfo::SetAmountOfPhysicalMemoryMbForTesting(
const uint64_t amount_of_memory_mb) {
std::optional<uint64_t> current = g_amount_of_physical_memory_mb_for_testing;
g_amount_of_physical_memory_mb_for_testing.emplace(amount_of_memory_mb);
return current;
}
// static
void SysInfo::ClearAmountOfPhysicalMemoryMbForTesting() {
g_amount_of_physical_memory_mb_for_testing.reset();
}
} // namespace base