base/threading/platform_thread_android.cc - chromium/src.git - Git at Google

 // 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/threading/platform_thread.h"

 #include <errno.h>
 #include <pthread.h>
 #include <stddef.h>
 #include <sys/prctl.h>
 #include <sys/resource.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <unistd.h>

 #include <algorithm>
 #include <iterator>
 #include <optional>
 #include <vector>

 #include "base/android/android_info.h"
 #include "base/android/jni_android.h"
 #include "base/feature_list.h"
 #include "base/logging.h"
 #include "base/system/sys_info.h"
 #include "base/threading/platform_thread_internal_posix.h"
 #include "base/threading/thread_id_name_manager.h"
 #include "base/trace_event/trace_event.h"

 // Must come after all headers that specialize FromJniType() / ToJniType().
 #include "base/tasks_jni/ThreadUtils_jni.h"

 namespace base {

 // Allows fine-grained control of thread priorities on Android.
 // Enable with e.g.
 // --enable-features=AndroidThreadPriority:presentation/-8/default/-1
 BASE_FEATURE(kAndroidThreadPriority, base::FEATURE_DISABLED_BY_DEFAULT);
 BASE_FEATURE_PARAM(int,
                    kBackgroundThreadPriority,
                    &kAndroidThreadPriority,
                    "background",
                    10);
 BASE_FEATURE_PARAM(int,
                    kUtilityThreadPriority,
                    &kAndroidThreadPriority,
                    "utility",
                    1);
 BASE_FEATURE_PARAM(int,
                    kDefaultThreadPriority,
                    &kAndroidThreadPriority,
                    "default",
                    0);
 BASE_FEATURE_PARAM(int,
                    kPresentationThreadPriority,
                    &kAndroidThreadPriority,
                    "presentation",
                    -4);
 BASE_FEATURE_PARAM(int,
                    kInteractiveThreadPriority,
                    &kAndroidThreadPriority,
                    "interactive",
                    -4);
 BASE_FEATURE_PARAM(bool,
                    kObeySocRestrictions,
                    &kAndroidThreadPriority,
                    "obey_soc_restrictions",
                    true);
 // kRealtimeAudio cannot be configured on the command line and should be the
 // effective maximum.

 // When enabled, do not run threads with a less important ThreadType than
 // kDisplayCritical on the big core cluster, for configurations with at least 3
 // clusters. This is based on observations that this cluster is both
 // power-hungry and contended.
 BASE_FEATURE(kRestrictBigCoreThreadAffinity, base::FEATURE_DISABLED_BY_DEFAULT);

 namespace {

 std::vector<uint64_t>* g_max_frequency_per_processor_override = nullptr;

 struct SetAffinityMask {
   // Only set when the current CPU configuration has at least 3 separate
   // clusters.
   std::optional<cpu_set_t> mask;
   size_t count = 0;
   int allowed_count = 0;
 };

 // Get the CPU affinity mask, given the maximum frequency of all cores, and
 // whether the mask should allow to run on the largest core cluster, for
 // configurations with at least 3 clusters.
 //
 // Returns a value where `mask.mask` is not set if the device is not eligible,
 // that is it does not have at least 3 different CPU types.
 SetAffinityMask GetAffinityMask(const std::vector<uint64_t>& max_frequencies,
                                 bool can_run) {
   if (max_frequencies.empty()) {
     return {};
   }

   auto sorted = max_frequencies;
   std::sort(sorted.begin(), sorted.end());
   uint64_t max_frequency = sorted[sorted.size() - 1];
   auto last = std::unique(sorted.begin(), sorted.end());
   ssize_t distinct_count = std::distance(sorted.begin(), last);

   // Don't want to move entirely from big cores on big.LITTLE, only on
   // little-mid-big designs.
   if (distinct_count < 3) {
     return {};
   }

   int allowed_cpus_count = 0;
   cpu_set_t cpu_set;
   // SAFETY: Here and below, these are macros that we don't control, and hence
   // we cannot safely replace. However, CPU_ZERO() is safe, and CPU_SET() has a
   // check internally to not overflow the bitset, which we repeat in the loop to
   // be clearer.
   UNSAFE_BUFFERS(CPU_ZERO(&cpu_set));
   for (size_t i = 0; i < max_frequencies.size(); i++) {
     if (i < CPU_SETSIZE) {
       if (can_run || (max_frequencies[i] < max_frequency)) {
         allowed_cpus_count++;
         UNSAFE_BUFFERS(CPU_SET(i, &cpu_set));
       }
     }
   }

   return {cpu_set, max_frequencies.size(), allowed_cpus_count};
 }

 }  // namespace

 void SetMaxFrequencyPerProcessorOverrideForTesting(
     std::vector<uint64_t>* value) {
   g_max_frequency_per_processor_override = value;
 }

 bool IsEligibleForBigCoreAffinityChange() {
   if (g_max_frequency_per_processor_override) {
     return GetAffinityMask(*g_max_frequency_per_processor_override, false)
         .mask.has_value();
   }
   static const bool eligible =
       GetAffinityMask(SysInfo::MaxFrequencyPerProcessor(), false)
           .mask.has_value();
   return eligible;
 }

 void SetCanRunOnBigCore(PlatformThreadId thread_id, bool can_run) {
   TRACE_EVENT("base", __PRETTY_FUNCTION__, "thread_id", thread_id, "can_run",
               can_run);
   SetAffinityMask mask;
   if (g_max_frequency_per_processor_override) {
     mask = GetAffinityMask(*g_max_frequency_per_processor_override, can_run);
   } else {
     static const SetAffinityMask all_cores_mask =
         GetAffinityMask(SysInfo::MaxFrequencyPerProcessor(), true);
     static const SetAffinityMask no_big_cores_mask =
         GetAffinityMask(SysInfo::MaxFrequencyPerProcessor(), false);
     mask = can_run ? all_cores_mask : no_big_cores_mask;
   }

   if (!mask.mask) {
     return;
   }

   TRACE_EVENT("base", "SetAffinity", "count", mask.count, "allowed",
               mask.allowed_count);
   // If the call fails, it's not a correctness issue. However we want to catch
   // the sandbox returning EPERM.
   //
   // For instance, an invalid mask (e.g. one with an empty intersection with the
   // set of possible CPUs) returns EINVAL and does not change the current mask,
   // per sched_setaffinity(2). On more recent kernels, an empty mask resets the
   // affinity.
   int retval =
       sched_setaffinity(thread_id.raw(), sizeof(*mask.mask), &*mask.mask);
   DPCHECK(!retval);
 }

 namespace internal {

 static int GetAdjustedPresentationThreadPriority() {
   // ADPF-equipped Google Pixels seem to have issues with input jank if the
   // kDisplayCriticalThreadPriority value is lowered below -4.
   static bool is_google_soc = SysInfo::SocManufacturer() == "Google";
   const bool allowed_to_lower =
       (!is_google_soc || !kObeySocRestrictions.Get()) &&
       base::FeatureList::IsEnabled(kAndroidThreadPriority);
   const int requested_priority = kPresentationThreadPriority.Get();
   return allowed_to_lower ? requested_priority
                           : std::max(-4, requested_priority);
 }

 // - kRealtimeAudio corresponds to Android's PRIORITY_AUDIO = -16 value.
 // - kPresentation corresponds to Android's PRIORITY_DISPLAY = -4 value.
 // - kUtility corresponds to Android's THREAD_PRIORITY_LESS_FAVORABLE = 1 value.
 // - kBackground corresponds to Android's PRIORITY_BACKGROUND = 10
 //   value. Contrary to the matching Java APi in Android <13, this does not
 //   restrict the thread to (subset of) little cores.
 const ThreadTypeToNiceValuePairForTest kThreadTypeToNiceValueMapForTest[7] = {
     {ThreadType::kRealtimeAudio, -16}, {ThreadType::kPresentation, -4},
     {ThreadType::kDefault, 0},         {ThreadType::kUtility, 1},
     {ThreadType::kBackground, 10},
 };

 // If we're not in the AndroidThreadPriorityTrial:
 //    - kBackground corresponds to Android's PRIORITY_BACKGROUND = 10 value.
 //    - kUtility corresponds to Android's THREAD_PRIORITY_LESS_FAVORABLE = 1
 //      value.
 //    - kPresentation and kInteractive correspond to Android's
 //      PRIORITY_DISPLAY = -4 value.
 //    - kRealtimeAudio corresponds to Android's PRIORITY_AUDIO = -16 value.
 int ThreadTypeToNiceValue(const ThreadType thread_type) {
   if (base::FeatureList::IsEnabled(kAndroidThreadPriority)) {
     [[unlikely]]
     // Establish weak partial ordering from high to low.
     DCHECK_LE(kUtilityThreadPriority.Get(), kBackgroundThreadPriority.Get());
     DCHECK_LE(kDefaultThreadPriority.Get(), kUtilityThreadPriority.Get());
     DCHECK_LE(GetAdjustedPresentationThreadPriority(),
               kDefaultThreadPriority.Get());
     DCHECK_LE(kInteractiveThreadPriority.Get(),
               GetAdjustedPresentationThreadPriority());
     // Check that -16 is the highest priority in the system.
     DCHECK_LT(-16, kInteractiveThreadPriority.Get());
     switch (thread_type) {
       case ThreadType::kBackground:
         return kBackgroundThreadPriority.Get();
       case ThreadType::kUtility:
         return kUtilityThreadPriority.Get();
       case ThreadType::kDefault:
         return kDefaultThreadPriority.Get();
       case ThreadType::kPresentation:
         return GetAdjustedPresentationThreadPriority();
       case ThreadType::kAudioProcessing:
         return kInteractiveThreadPriority.Get();
       case ThreadType::kRealtimeAudio:
         // Not configurable, should be the effective highest.
         return -16;
     }
   }
   switch (thread_type) {
     case ThreadType::kBackground:
       return 10;
     case ThreadType::kUtility:
       return 1;
     case ThreadType::kDefault:
       return 0;
     case ThreadType::kPresentation:
     case ThreadType::kAudioProcessing:
       return -4;
     case ThreadType::kRealtimeAudio:
       return -16;
   }
 }

 bool CanSetThreadTypeToRealtimeAudio() {
   return true;
 }

 void SetCurrentThreadTypeImpl(ThreadType thread_type,
                               MessagePumpType pump_type_hint) {
   // We set the Audio priority through JNI as the Java setThreadPriority will
   // put it into a preferable cgroup, whereas the "normal" C++ call wouldn't.
   // However, with
   // https://android-review.googlesource.com/c/platform/system/core/+/1975808
   // this becomes obsolete and we can avoid this starting in API level 33.
   if (thread_type == ThreadType::kRealtimeAudio &&
       base::android::android_info::sdk_int() <
           base::android::android_info::SDK_VERSION_T) {
     JNIEnv* env = base::android::AttachCurrentThread();
     Java_ThreadUtils_setThreadPriorityAudio(env,
                                             PlatformThread::CurrentId().raw());
   } else if (thread_type == ThreadType::kPresentation &&
              pump_type_hint == MessagePumpType::UI &&
              GetCurrentThreadNiceValue() <=
                  ThreadTypeToNiceValue(ThreadType::kPresentation)) {
     // Recent versions of Android (O+) up the priority of the UI thread
     // automatically.
   } else {
     SetThreadNiceFromType(PlatformThread::CurrentId(), thread_type);
   }

   if (IsEligibleForBigCoreAffinityChange() &&
       base::FeatureList::IsEnabled(kRestrictBigCoreThreadAffinity)) {
     SetCanRunOnBigCore(PlatformThread::CurrentId(),
                        thread_type >= ThreadType::kPresentation);
   }
 }

 std::optional<ThreadType> GetCurrentEffectiveThreadTypeForPlatformForTest() {
   JNIEnv* env = base::android::AttachCurrentThread();
   if (Java_ThreadUtils_isThreadPriorityAudio(
           env, PlatformThread::CurrentId().raw())) {
     return std::make_optional(ThreadType::kRealtimeAudio);
   }
   return std::nullopt;
 }

 PlatformPriorityOverride SetThreadTypeOverride(
     PlatformThreadHandle thread_handle,
     ThreadType thread_type) {
   PlatformThreadId thread_id(
       pthread_gettid_np(thread_handle.platform_handle()));
   if (GetThreadNiceValue(thread_id) <= ThreadTypeToNiceValue(thread_type)) {
     return false;
   }
   return SetThreadNiceFromType(thread_id, thread_type);
 }

 void RemoveThreadTypeOverride(
     PlatformThreadHandle thread_handle,
     const PlatformPriorityOverride& priority_override_handle,
     ThreadType initial_thread_type) {
   if (!priority_override_handle) {
     return;
   }

   PlatformThreadId thread_id(
       pthread_gettid_np(thread_handle.platform_handle()));
   SetThreadNiceFromType(thread_id, initial_thread_type);
 }

 }  // namespace internal

 void PlatformThread::SetName(const std::string& name) {
   SetNameCommon(name);

   // Like linux, on android we can get the thread names to show up in the
   // debugger by setting the process name for the LWP.
   // We don't want to do this for the main thread because that would rename
   // the process, causing tools like killall to stop working.
   if (PlatformThread::CurrentId().raw() == getpid()) {
     return;
   }

   // Set the name for the LWP (which gets truncated to 15 characters).
   int err = prctl(PR_SET_NAME, name.c_str());
   if (err < 0 && errno != EPERM) {
     DPLOG(ERROR) << "prctl(PR_SET_NAME)";
   }
 }

 void InitThreading() {}

 void TerminateOnThread() {
   base::android::DetachFromVM();
 }

 size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) {
 #if !defined(ADDRESS_SANITIZER)
   return 0;
 #else
   // AddressSanitizer bloats the stack approximately 2x. Default stack size of
   // 1Mb is not enough for some tests (see http://crbug.com/263749 for example).
   return 2 * (1 << 20);  // 2Mb
 #endif
 }

 }  // namespace base

 DEFINE_JNI(ThreadUtils)
	// 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/threading/platform_thread.h"

	#include <errno.h>
	#include <pthread.h>
	#include <stddef.h>
	#include <sys/prctl.h>
	#include <sys/resource.h>
	#include <sys/time.h>
	#include <sys/types.h>
	#include <unistd.h>

	#include <algorithm>
	#include <iterator>
	#include <optional>
	#include <vector>

	#include "base/android/android_info.h"
	#include "base/android/jni_android.h"
	#include "base/feature_list.h"
	#include "base/logging.h"
	#include "base/system/sys_info.h"
	#include "base/threading/platform_thread_internal_posix.h"
	#include "base/threading/thread_id_name_manager.h"
	#include "base/trace_event/trace_event.h"

	// Must come after all headers that specialize FromJniType() / ToJniType().
	#include "base/tasks_jni/ThreadUtils_jni.h"

	namespace base {

	// Allows fine-grained control of thread priorities on Android.
	// Enable with e.g.
	// --enable-features=AndroidThreadPriority:presentation/-8/default/-1
	BASE_FEATURE(kAndroidThreadPriority, base::FEATURE_DISABLED_BY_DEFAULT);
	BASE_FEATURE_PARAM(int,
	kBackgroundThreadPriority,
	&kAndroidThreadPriority,
	"background",
	10);
	BASE_FEATURE_PARAM(int,
	kUtilityThreadPriority,
	&kAndroidThreadPriority,
	"utility",
	1);
	BASE_FEATURE_PARAM(int,
	kDefaultThreadPriority,
	&kAndroidThreadPriority,
	"default",
	0);
	BASE_FEATURE_PARAM(int,
	kPresentationThreadPriority,
	&kAndroidThreadPriority,
	"presentation",
	-4);
	BASE_FEATURE_PARAM(int,
	kInteractiveThreadPriority,
	&kAndroidThreadPriority,
	"interactive",
	-4);
	BASE_FEATURE_PARAM(bool,
	kObeySocRestrictions,
	&kAndroidThreadPriority,
	"obey_soc_restrictions",
	true);
	// kRealtimeAudio cannot be configured on the command line and should be the
	// effective maximum.

	// When enabled, do not run threads with a less important ThreadType than
	// kDisplayCritical on the big core cluster, for configurations with at least 3
	// clusters. This is based on observations that this cluster is both
	// power-hungry and contended.
	BASE_FEATURE(kRestrictBigCoreThreadAffinity, base::FEATURE_DISABLED_BY_DEFAULT);

	namespace {

	std::vector<uint64_t>* g_max_frequency_per_processor_override = nullptr;

	struct SetAffinityMask {
	// Only set when the current CPU configuration has at least 3 separate
	// clusters.
	std::optional<cpu_set_t> mask;
	size_t count = 0;
	int allowed_count = 0;
	};

	// Get the CPU affinity mask, given the maximum frequency of all cores, and
	// whether the mask should allow to run on the largest core cluster, for
	// configurations with at least 3 clusters.
	//
	// Returns a value where `mask.mask` is not set if the device is not eligible,
	// that is it does not have at least 3 different CPU types.
	SetAffinityMask GetAffinityMask(const std::vector<uint64_t>& max_frequencies,
	bool can_run) {
	if (max_frequencies.empty()) {
	return {};
	}

	auto sorted = max_frequencies;
	std::sort(sorted.begin(), sorted.end());
	uint64_t max_frequency = sorted[sorted.size() - 1];
	auto last = std::unique(sorted.begin(), sorted.end());
	ssize_t distinct_count = std::distance(sorted.begin(), last);

	// Don't want to move entirely from big cores on big.LITTLE, only on
	// little-mid-big designs.
	if (distinct_count < 3) {
	return {};
	}

	int allowed_cpus_count = 0;
	cpu_set_t cpu_set;
	// SAFETY: Here and below, these are macros that we don't control, and hence
	// we cannot safely replace. However, CPU_ZERO() is safe, and CPU_SET() has a
	// check internally to not overflow the bitset, which we repeat in the loop to
	// be clearer.
	UNSAFE_BUFFERS(CPU_ZERO(&cpu_set));
	for (size_t i = 0; i < max_frequencies.size(); i++) {
	if (i < CPU_SETSIZE) {
	if (can_run \|\| (max_frequencies[i] < max_frequency)) {
	allowed_cpus_count++;
	UNSAFE_BUFFERS(CPU_SET(i, &cpu_set));
	}
	}
	}

	return {cpu_set, max_frequencies.size(), allowed_cpus_count};
	}

	} // namespace

	void SetMaxFrequencyPerProcessorOverrideForTesting(
	std::vector<uint64_t>* value) {
	g_max_frequency_per_processor_override = value;
	}

	bool IsEligibleForBigCoreAffinityChange() {
	if (g_max_frequency_per_processor_override) {
	return GetAffinityMask(*g_max_frequency_per_processor_override, false)
	.mask.has_value();
	}
	static const bool eligible =
	GetAffinityMask(SysInfo::MaxFrequencyPerProcessor(), false)
	.mask.has_value();
	return eligible;
	}

	void SetCanRunOnBigCore(PlatformThreadId thread_id, bool can_run) {
	TRACE_EVENT("base", __PRETTY_FUNCTION__, "thread_id", thread_id, "can_run",
	can_run);
	SetAffinityMask mask;
	if (g_max_frequency_per_processor_override) {
	mask = GetAffinityMask(*g_max_frequency_per_processor_override, can_run);
	} else {
	static const SetAffinityMask all_cores_mask =
	GetAffinityMask(SysInfo::MaxFrequencyPerProcessor(), true);
	static const SetAffinityMask no_big_cores_mask =
	GetAffinityMask(SysInfo::MaxFrequencyPerProcessor(), false);
	mask = can_run ? all_cores_mask : no_big_cores_mask;
	}

	if (!mask.mask) {
	return;
	}

	TRACE_EVENT("base", "SetAffinity", "count", mask.count, "allowed",
	mask.allowed_count);
	// If the call fails, it's not a correctness issue. However we want to catch
	// the sandbox returning EPERM.
	//
	// For instance, an invalid mask (e.g. one with an empty intersection with the
	// set of possible CPUs) returns EINVAL and does not change the current mask,
	// per sched_setaffinity(2). On more recent kernels, an empty mask resets the
	// affinity.
	int retval =
	sched_setaffinity(thread_id.raw(), sizeof(mask.mask), &mask.mask);
	DPCHECK(!retval);
	}

	namespace internal {

	static int GetAdjustedPresentationThreadPriority() {
	// ADPF-equipped Google Pixels seem to have issues with input jank if the
	// kDisplayCriticalThreadPriority value is lowered below -4.
	static bool is_google_soc = SysInfo::SocManufacturer() == "Google";
	const bool allowed_to_lower =
	(!is_google_soc \|\| !kObeySocRestrictions.Get()) &&
	base::FeatureList::IsEnabled(kAndroidThreadPriority);
	const int requested_priority = kPresentationThreadPriority.Get();
	return allowed_to_lower ? requested_priority
	: std::max(-4, requested_priority);
	}

	// - kRealtimeAudio corresponds to Android's PRIORITY_AUDIO = -16 value.
	// - kPresentation corresponds to Android's PRIORITY_DISPLAY = -4 value.
	// - kUtility corresponds to Android's THREAD_PRIORITY_LESS_FAVORABLE = 1 value.
	// - kBackground corresponds to Android's PRIORITY_BACKGROUND = 10
	// value. Contrary to the matching Java APi in Android <13, this does not
	// restrict the thread to (subset of) little cores.
	const ThreadTypeToNiceValuePairForTest kThreadTypeToNiceValueMapForTest[7] = {
	{ThreadType::kRealtimeAudio, -16}, {ThreadType::kPresentation, -4},
	{ThreadType::kDefault, 0}, {ThreadType::kUtility, 1},
	{ThreadType::kBackground, 10},
	};

	// If we're not in the AndroidThreadPriorityTrial:
	// - kBackground corresponds to Android's PRIORITY_BACKGROUND = 10 value.
	// - kUtility corresponds to Android's THREAD_PRIORITY_LESS_FAVORABLE = 1
	// value.
	// - kPresentation and kInteractive correspond to Android's
	// PRIORITY_DISPLAY = -4 value.
	// - kRealtimeAudio corresponds to Android's PRIORITY_AUDIO = -16 value.
	int ThreadTypeToNiceValue(const ThreadType thread_type) {
	if (base::FeatureList::IsEnabled(kAndroidThreadPriority)) {
	[[unlikely]]
	// Establish weak partial ordering from high to low.
	DCHECK_LE(kUtilityThreadPriority.Get(), kBackgroundThreadPriority.Get());
	DCHECK_LE(kDefaultThreadPriority.Get(), kUtilityThreadPriority.Get());
	DCHECK_LE(GetAdjustedPresentationThreadPriority(),
	kDefaultThreadPriority.Get());
	DCHECK_LE(kInteractiveThreadPriority.Get(),
	GetAdjustedPresentationThreadPriority());
	// Check that -16 is the highest priority in the system.
	DCHECK_LT(-16, kInteractiveThreadPriority.Get());
	switch (thread_type) {
	case ThreadType::kBackground:
	return kBackgroundThreadPriority.Get();
	case ThreadType::kUtility:
	return kUtilityThreadPriority.Get();
	case ThreadType::kDefault:
	return kDefaultThreadPriority.Get();
	case ThreadType::kPresentation:
	return GetAdjustedPresentationThreadPriority();
	case ThreadType::kAudioProcessing:
	return kInteractiveThreadPriority.Get();
	case ThreadType::kRealtimeAudio:
	// Not configurable, should be the effective highest.
	return -16;
	}
	}
	switch (thread_type) {
	case ThreadType::kBackground:
	return 10;
	case ThreadType::kUtility:
	return 1;
	case ThreadType::kDefault:
	return 0;
	case ThreadType::kPresentation:
	case ThreadType::kAudioProcessing:
	return -4;
	case ThreadType::kRealtimeAudio:
	return -16;
	}
	}

	bool CanSetThreadTypeToRealtimeAudio() {
	return true;
	}

	void SetCurrentThreadTypeImpl(ThreadType thread_type,
	MessagePumpType pump_type_hint) {
	// We set the Audio priority through JNI as the Java setThreadPriority will
	// put it into a preferable cgroup, whereas the "normal" C++ call wouldn't.
	// However, with
	// https://android-review.googlesource.com/c/platform/system/core/+/1975808
	// this becomes obsolete and we can avoid this starting in API level 33.
	if (thread_type == ThreadType::kRealtimeAudio &&
	base::android::android_info::sdk_int() <
	base::android::android_info::SDK_VERSION_T) {
	JNIEnv* env = base::android::AttachCurrentThread();
	Java_ThreadUtils_setThreadPriorityAudio(env,
	PlatformThread::CurrentId().raw());
	} else if (thread_type == ThreadType::kPresentation &&
	pump_type_hint == MessagePumpType::UI &&
	GetCurrentThreadNiceValue() <=
	ThreadTypeToNiceValue(ThreadType::kPresentation)) {
	// Recent versions of Android (O+) up the priority of the UI thread
	// automatically.
	} else {
	SetThreadNiceFromType(PlatformThread::CurrentId(), thread_type);
	}

	if (IsEligibleForBigCoreAffinityChange() &&
	base::FeatureList::IsEnabled(kRestrictBigCoreThreadAffinity)) {
	SetCanRunOnBigCore(PlatformThread::CurrentId(),
	thread_type >= ThreadType::kPresentation);
	}
	}

	std::optional<ThreadType> GetCurrentEffectiveThreadTypeForPlatformForTest() {
	JNIEnv* env = base::android::AttachCurrentThread();
	if (Java_ThreadUtils_isThreadPriorityAudio(
	env, PlatformThread::CurrentId().raw())) {
	return std::make_optional(ThreadType::kRealtimeAudio);
	}
	return std::nullopt;
	}

	PlatformPriorityOverride SetThreadTypeOverride(
	PlatformThreadHandle thread_handle,
	ThreadType thread_type) {
	PlatformThreadId thread_id(
	pthread_gettid_np(thread_handle.platform_handle()));
	if (GetThreadNiceValue(thread_id) <= ThreadTypeToNiceValue(thread_type)) {
	return false;
	}
	return SetThreadNiceFromType(thread_id, thread_type);
	}

	void RemoveThreadTypeOverride(
	PlatformThreadHandle thread_handle,
	const PlatformPriorityOverride& priority_override_handle,
	ThreadType initial_thread_type) {
	if (!priority_override_handle) {
	return;
	}

	PlatformThreadId thread_id(
	pthread_gettid_np(thread_handle.platform_handle()));
	SetThreadNiceFromType(thread_id, initial_thread_type);
	}

	} // namespace internal

	void PlatformThread::SetName(const std::string& name) {
	SetNameCommon(name);

	// Like linux, on android we can get the thread names to show up in the
	// debugger by setting the process name for the LWP.
	// We don't want to do this for the main thread because that would rename
	// the process, causing tools like killall to stop working.
	if (PlatformThread::CurrentId().raw() == getpid()) {
	return;
	}

	// Set the name for the LWP (which gets truncated to 15 characters).
	int err = prctl(PR_SET_NAME, name.c_str());
	if (err < 0 && errno != EPERM) {
	DPLOG(ERROR) << "prctl(PR_SET_NAME)";
	}
	}

	void InitThreading() {}

	void TerminateOnThread() {
	base::android::DetachFromVM();
	}

	size_t GetDefaultThreadStackSize(const pthread_attr_t& attributes) {
	#if !defined(ADDRESS_SANITIZER)
	return 0;
	#else
	// AddressSanitizer bloats the stack approximately 2x. Default stack size of
	// 1Mb is not enough for some tests (see http://crbug.com/263749 for example).
	return 2 * (1 << 20); // 2Mb
	#endif
	}

	} // namespace base

	DEFINE_JNI(ThreadUtils)