brpc/src/bthread/task_control.cpp at master · apache/brpc · GitHub

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// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements. See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership. The ASF licenses this file

// to you under the Apache License, Version 2.0 (the

// "License"); you may not use this file except in compliance

// with the License. You may obtain a copy of the License at

// http://www.apache.org/licenses/LICENSE-2.0

// Unless required by applicable law or agreed to in writing,

// software distributed under the License is distributed on an

// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

// KIND, either express or implied. See the License for the

// specific language governing permissions and limitations

// under the License.

// bthread - An M:N threading library to make applications more concurrent.

// Date: Tue Jul 10 17:40:58 CST 2012

#include <pthread.h>

#include <set>

#include <regex>

#include <sys/syscall.h> // SYS_gettid

#include "butil/scoped_lock.h" // BAIDU_SCOPED_LOCK

#include "butil/errno.h" // berror

#include "butil/logging.h"

#include "butil/threading/platform_thread.h"

#include "butil/third_party/murmurhash3/murmurhash3.h"

#include "bthread/sys_futex.h" // futex_wake_private

#include "bthread/interrupt_pthread.h"

#include "bthread/processor.h" // cpu_relax

#include "bthread/task_group.h" // TaskGroup

#include "bthread/task_control.h"

#include "bthread/timer_thread.h" // global_timer_thread

#include <gflags/gflags.h>

#include "bthread/log.h"

#if defined(OS_MACOSX)

#include <mach/mach.h>

#endif

DEFINE_int32(task_group_delete_delay, 1,

"delay deletion of TaskGroup for so many seconds");

DEFINE_int32(task_group_runqueue_capacity, 4096,

"capacity of runqueue in each TaskGroup");

DEFINE_int32(task_group_ntags, 1, "TaskGroup will be grouped by number ntags");

DEFINE_bool(task_group_set_worker_name, true,

"Whether to set the name of the worker thread");

DEFINE_string(cpu_set, "",

"Set of CPUs to which worker threads are bound. "

"Two formats are supported:\n"

" Legacy (bind all tags to one set): \"0-3,5,7\"\n"

" Per-tag: \"0:0-3,5,7;1:6-9,4\" "

"where the number before ':' is the bthread_tag and the part "

"after ':' is a CPU list in the same format as the legacy value. "

"Tags not mentioned get no CPU binding. Default: disable.");

DEFINE_int32(event_dispatcher_num, 1, "Number of event dispatcher");

namespace bthread {

DEFINE_bool(parking_lot_no_signal_when_no_waiter, false,

"ParkingLot doesn't signal when there is no waiter. "

"In busy worker scenarios, signal overhead can be reduced.");

DEFINE_bool(enable_bthread_priority_queue, false, "Whether to enable priority queue");

DECLARE_int32(bthread_concurrency);

DECLARE_int32(bthread_min_concurrency);

DECLARE_int32(bthread_parking_lot_of_each_tag);

extern pthread_mutex_t g_task_control_mutex;

EXTERN_BAIDU_VOLATILE_THREAD_LOCAL(TaskGroup*, tls_task_group);

void (*g_worker_startfn)() = nullptr;

void (*g_tagged_worker_startfn)(bthread_tag_t) = nullptr;

// May be called in other modules to run startfn in non-worker pthreads.

void run_worker_startfn() {

if (g_worker_startfn) {

g_worker_startfn();

}

void run_tagged_worker_startfn(bthread_tag_t tag) {

if (g_tagged_worker_startfn) {

g_tagged_worker_startfn(tag);

}

struct WorkerThreadArgs {

WorkerThreadArgs(TaskControl* _c, bthread_tag_t _t) : c(_c), tag(_t) {}

TaskControl* c;

bthread_tag_t tag;

};

void* TaskControl::worker_thread(void* arg) {

run_worker_startfn();

#ifdef BAIDU_INTERNAL

logging::ComlogInitializer comlog_initializer;

#endif

auto dummy = static_cast<WorkerThreadArgs*>(arg);

auto c = dummy->c;

auto tag = dummy->tag;

delete dummy;

run_tagged_worker_startfn(tag);

TaskGroup* g = c->create_group(tag);

TaskStatistics stat;

if (nullptr == g) {

LOG(ERROR) << "Fail to create TaskGroup in pthread=" << pthread_self();

return nullptr;

}

g->_tid = pthread_self();

// tag_wid is a per-tag monotonic counter: same-tag workers get 0,1,2,...

// Used both for CPU round-robin affinity and the thread name suffix.

int tag_wid = c->_tag_next_worker_id[tag].fetch_add(

1, butil::memory_order_relaxed);

if (!c->_tag_cpus[tag].empty()) {

const auto& cpus = c->_tag_cpus[tag];

bind_thread_to_cpu(pthread_self(), cpus[tag_wid % cpus.size()]);

}

if (FLAGS_task_group_set_worker_name) {

std::string worker_thread_name = butil::string_printf(

"brpc_wkr:%d-%d", g->tag(), tag_wid);

butil::PlatformThread::SetNameSimple(worker_thread_name.c_str());

}

BT_VLOG << "Created worker=" << pthread_self() << " tid=" << g->_tid

<< " bthread=" << g->main_tid() << " tag=" << g->tag();

BAIDU_SET_VOLATILE_THREAD_LOCAL(tls_task_group, g);

c->_nworkers << 1;

c->tag_nworkers(g->tag()) << 1;

g->run_main_task();

stat = g->main_stat();

BT_VLOG << "Destroying worker=" << pthread_self() << " bthread="

<< g->main_tid() << " idle=" << stat.cputime_ns / 1000000.0

<< "ms uptime=" << g->current_uptime_ns() / 1000000.0 << "ms";

BAIDU_SET_VOLATILE_THREAD_LOCAL(tls_task_group, nullptr);

g->destroy_self();

c->_nworkers << -1;

c->tag_nworkers(g->tag()) << -1;

return nullptr;

}

TaskGroup* TaskControl::create_group(bthread_tag_t tag) {

TaskGroup* g = new TaskGroup(this);

if (g->init(FLAGS_task_group_runqueue_capacity) != 0) {

LOG(ERROR) << "Fail to init TaskGroup";

delete g;

return nullptr;

}

if (_add_group(g, tag) != 0) {

delete g;

return nullptr;

}

return g;

}

static void print_rq_sizes_in_the_tc(std::ostream &os, void *arg) {

TaskControl *tc = (TaskControl *)arg;

tc->print_rq_sizes(os);

}

static double get_cumulated_worker_time_from_this(void *arg) {

return static_cast<TaskControl*>(arg)->get_cumulated_worker_time();

}

struct CumulatedWithTagArgs {

CumulatedWithTagArgs(TaskControl* _c, bthread_tag_t _t) : c(_c), t(_t) {}

TaskControl* c;

bthread_tag_t t;

};

static double get_cumulated_worker_time_from_this_with_tag(void* arg) {

auto a = static_cast<CumulatedWithTagArgs*>(arg);

auto c = a->c;

auto t = a->t;

return c->get_cumulated_worker_time(t);

}

static int64_t get_cumulated_switch_count_from_this(void *arg) {

return static_cast<TaskControl*>(arg)->get_cumulated_switch_count();

}

static int64_t get_cumulated_signal_count_from_this(void *arg) {

return static_cast<TaskControl*>(arg)->get_cumulated_signal_count();

}

TaskControl::TaskControl()

// NOTE: all fileds must be initialized before the vars.

: _tagged_ngroup(FLAGS_task_group_ntags)

, _tagged_groups(FLAGS_task_group_ntags)

, _init(false)

, _stop(false)

, _concurrency(0)

, _nworkers("bthread_worker_count")

, _pending_time(nullptr)

// Delay exposure of following two vars because they rely on TC which

// is not initialized yet.

, _cumulated_worker_time(get_cumulated_worker_time_from_this, this)

, _worker_usage_second(&_cumulated_worker_time, 1)

, _cumulated_switch_count(get_cumulated_switch_count_from_this, this)

, _switch_per_second(&_cumulated_switch_count)

, _cumulated_signal_count(get_cumulated_signal_count_from_this, this)

, _signal_per_second(&_cumulated_signal_count)

, _status(print_rq_sizes_in_the_tc, this)

, _nbthreads("bthread_count")

, _enable_priority_queue(FLAGS_enable_bthread_priority_queue)

, _ed_priority_queue_num_of_each_tag(FLAGS_event_dispatcher_num)

, _ed_priority_queues(

FLAGS_task_group_ntags * FLAGS_event_dispatcher_num)

, _pl_num_of_each_tag(FLAGS_bthread_parking_lot_of_each_tag)

, _tagged_pl(FLAGS_task_group_ntags)

, _tag_cpus(FLAGS_task_group_ntags)

, _tag_next_worker_id(FLAGS_task_group_ntags)

{}

int TaskControl::init_ed_priority_queues() {

if (!_enable_priority_queue) {

return 0;

}

for (int i = 0; i < FLAGS_task_group_ntags; ++i) {

for (int j = 0;

j < _ed_priority_queue_num_of_each_tag; ++j) {

if (ed_priority_queue(i, j).init(

BTHREAD_MAX_CONCURRENCY) != 0) {

LOG(ERROR) << "Fail to init priority queue for tag=" << i

<< " ed=" << j;

return -1;

}

return 0;

}

int TaskControl::init(int concurrency) {

if (_concurrency != 0) {

LOG(ERROR) << "Already initialized";

return -1;

}

if (concurrency <= 0) {

LOG(ERROR) << "Invalid concurrency=" << concurrency;

return -1;

}

_concurrency = concurrency;

if (!FLAGS_cpu_set.empty()) {

if (parse_cpuset(FLAGS_cpu_set) == -1) {

LOG(ERROR) << "invalid cpu_set=" << FLAGS_cpu_set;

return -1;

}

// task group group by tags

for (int i = 0; i < FLAGS_task_group_ntags; ++i) {

_tagged_ngroup[i].store(0, std::memory_order_relaxed);

auto tag_str = std::to_string(i);

_tagged_nworkers.emplace_back(

std::make_unique<bvar::Adder<int64_t>>("bthread_worker_count", tag_str));

_tagged_cumulated_worker_time_args.emplace_back(

std::make_unique<CumulatedWithTagArgs>(this, i));

_tagged_cumulated_worker_time.emplace_back(

std::make_unique<bvar::PassiveStatus<double>>(

get_cumulated_worker_time_from_this_with_tag,

_tagged_cumulated_worker_time_args.back().get()));

_tagged_worker_usage_second.emplace_back(

std::make_unique<bvar::PerSecond<bvar::PassiveStatus<double>>>(

"bthread_worker_usage", tag_str,

_tagged_cumulated_worker_time.back().get(), 1));

_tagged_nbthreads.emplace_back(

std::make_unique<bvar::Adder<int64_t>>("bthread_count", tag_str));

}

if (init_ed_priority_queues() != 0) {

return -1;

}

// Make sure TimerThread is ready.

if (get_or_create_global_timer_thread() == nullptr) {

LOG(ERROR) << "Fail to get global_timer_thread";

return -1;

}

#ifdef BRPC_BTHREAD_TRACER

if (!_task_tracer.Init()) {

LOG(ERROR) << "Fail to init TaskTracer";

return -1;

}

#endif // BRPC_BTHREAD_TRACER

_workers.resize(_concurrency);

for (int i = 0; i < _concurrency; ++i) {

auto arg = new WorkerThreadArgs(this, i % FLAGS_task_group_ntags);

const int rc = pthread_create(&_workers[i], nullptr, worker_thread, arg);

if (rc) {

delete arg;

PLOG(ERROR) << "Fail to create _workers[" << i << "]";

return -1;

}

_worker_usage_second.expose("bthread_worker_usage");

_switch_per_second.expose("bthread_switch_second");

_signal_per_second.expose("bthread_signal_second");

_status.expose("bthread_group_status");

// Wait for at least one group is added so that choose_one_group()

// never returns nullptr.

// TODO: Handle the case that worker quits before add_group

for (int i = 0; i < FLAGS_task_group_ntags;) {

if (_tagged_ngroup[i].load(std::memory_order_acquire) == 0) {

usleep(100); // TODO: Elaborate

continue;

}

++i;

}

_init.store(true, butil::memory_order_release);

return 0;

}

int TaskControl::add_workers(int num, bthread_tag_t tag) {

if (num <= 0) {

return 0;

}

try {

_workers.resize(_concurrency + num);

} catch (...) {

return 0;

}

const int old_concurency = _concurrency.load(butil::memory_order_relaxed);

for (int i = 0; i < num; ++i) {

// Worker will add itself to _idle_workers, so we have to add

// _concurrency before create a worker.

_concurrency.fetch_add(1);

auto arg = new WorkerThreadArgs(this, tag);

const int rc = pthread_create(

&_workers[i + old_concurency], nullptr, worker_thread, arg);

if (rc) {

delete arg;

PLOG(WARNING) << "Fail to create _workers[" << i + old_concurency << "]";

_concurrency.fetch_sub(1, butil::memory_order_release);

break;

}

// Cannot fail

_workers.resize(_concurrency.load(butil::memory_order_relaxed));

return _concurrency.load(butil::memory_order_relaxed) - old_concurency;

}

TaskGroup* TaskControl::choose_one_group(bthread_tag_t tag) {

CHECK(tag >= BTHREAD_TAG_DEFAULT && tag < FLAGS_task_group_ntags) << tag;

auto& groups = tag_group(tag);

const auto ngroup = tag_ngroup(tag).load(butil::memory_order_acquire);

if (ngroup != 0) {

return groups[butil::fast_rand_less_than(ngroup)];

}

CHECK(false) << "Impossible: ngroup is 0";

return nullptr;

}

// Parse a single cpu-range-list such as "0-3,5,7" into a sorted, deduplicated

// vector of CPU IDs. Returns 0 on success, -1 on error.

static int parse_one_cpuset(const std::string& value, std::vector<unsigned>& cpus) {

static std::regex r("(\\d+-)?(\\d+)(,(\\d+-)?(\\d+))*");

std::smatch match;

std::set<unsigned> cpuset;

if (value.empty()) {

return -1;

}

if (!std::regex_match(value, match, r)) {

return -1;

}

for (butil::StringSplitter split(value.data(), ','); split; ++split) {

butil::StringPiece cpu_ids(split.field(), split.length());

cpu_ids.trim_spaces();

butil::StringPiece begin = cpu_ids;

butil::StringPiece end = cpu_ids;

auto dash = cpu_ids.find('-');

if (dash != cpu_ids.npos) {

begin = cpu_ids.substr(0, dash);

end = cpu_ids.substr(dash + 1);

}

unsigned first = UINT_MAX;

unsigned last = 0;

int ret = butil::StringSplitter(begin, '\t').to_uint(&first);

ret = ret | butil::StringSplitter(end, '\t').to_uint(&last);

if (ret != 0 || first > last) {

return -1;

}

for (auto i = first; i <= last; ++i) {

cpuset.insert(i);

}

cpus.assign(cpuset.begin(), cpuset.end());

return 0;

}

int TaskControl::parse_cpuset(const std::string& value) {

if (value.empty()) {

return -1;

}

const int ntags = static_cast<int>(_tag_cpus.size());

// Detect per-tag format by the presence of ':' or ';'.

// Legacy format ("0-3,5,7") never contains these characters.

bool per_tag_format = (value.find(';') != std::string::npos ||

value.find(':') != std::string::npos);

if (per_tag_format) {

// Per-tag format: "0:0-3,5,7;1:6-9,4"

for (butil::StringSplitter seg_split(value.data(), ';'); seg_split; ++seg_split) {

std::string segment(seg_split.field(), seg_split.length());

// Trim leading/trailing spaces.

auto s = segment.find_first_not_of(' ');

auto e = segment.find_last_not_of(' ');

if (s == std::string::npos) { continue; } // blank segment

segment = segment.substr(s, e - s + 1);

auto colon = segment.find(':');

if (colon == std::string::npos) {

LOG(ERROR) << "cpu_set per-tag segment missing ':': " << segment;

return -1;

}

std::string tag_str = segment.substr(0, colon);

std::string cpus_str = segment.substr(colon + 1);

unsigned tag_id = 0;

butil::StringPiece tag_sp(tag_str);

if (butil::StringSplitter(tag_sp, '\t').to_uint(&tag_id) != 0) {

LOG(ERROR) << "cpu_set invalid tag '" << tag_str << "'";

return -1;

}

if ((int)tag_id >= ntags) {

LOG(ERROR) << "cpu_set tag " << tag_id

<< " >= task_group_ntags " << ntags;

return -1;

}

std::vector<unsigned> cpus;

if (parse_one_cpuset(cpus_str, cpus) != 0) {

LOG(ERROR) << "cpu_set invalid cpuset for tag " << tag_id

<< ": " << cpus_str;

return -1;

}

_tag_cpus[tag_id] = std::move(cpus);

}

} else {

// Legacy format: one cpu-set shared by all tags.

std::vector<unsigned> cpus;

if (parse_one_cpuset(value, cpus) != 0) {

LOG(ERROR) << "cpu_set invalid cpuset: " << value;

return -1;

}

for (int i = 0; i < ntags; ++i) {

_tag_cpus[i] = cpus;

}

return 0;

}

void TaskControl::bind_thread_to_cpu(pthread_t pthread, unsigned cpu_id) {

#if defined(OS_LINUX)

cpu_set_t cs;

CPU_ZERO(&cs);

CPU_SET(cpu_id, &cs);

auto r = pthread_setaffinity_np(pthread, sizeof(cs), &cs);

if (r != 0) {

LOG(WARNING) << "Failed to bind thread to cpu: " << cpu_id;

}

(void)r;

#elif defined(OS_MACOSX)

thread_port_t mach_thread = pthread_mach_thread_np(pthread);

if (mach_thread != MACH_PORT_NULL) {

LOG(WARNING) << "mach_thread is null"

<< "Failed to bind thread to cpu: " << cpu_id;

return;

}

thread_affinity_policy_data_t policy;

policy.affinity_tag = cpu_id;

if (thread_policy_set(mach_thread,

THREAD_AFFINITY_POLICY,

(thread_policy_t)&policy,

THREAD_AFFINITY_POLICY_COUNT) != KERN_SUCCESS) {

LOG(WARNING) << "Failed to bind thread to cpu: " << cpu_id;

}

#endif

}

#ifdef BRPC_BTHREAD_TRACER

void TaskControl::stack_trace(std::ostream& os, bthread_t tid) {

_task_tracer.Trace(os, tid);

}

std::string TaskControl::stack_trace(bthread_t tid) {

return _task_tracer.Trace(tid);

}

#endif // BRPC_BTHREAD_TRACER

extern int stop_and_join_epoll_threads();

void TaskControl::stop_and_join() {

// Close epoll threads so that worker threads are not waiting on epoll(

// which cannot be woken up by signal_task below)

CHECK_EQ(0, stop_and_join_epoll_threads());

// Stop workers

{

BAIDU_SCOPED_LOCK(_modify_group_mutex);

_stop = true;

std::for_each(

_tagged_ngroup.begin(), _tagged_ngroup.end(),

[](butil::atomic<size_t>& index) { index.store(0, butil::memory_order_relaxed); });

}

for (int i = 0; i < FLAGS_task_group_ntags; ++i) {

for (auto& pl : _tagged_pl[i]) {

pl.stop();

}

for (auto worker: _workers) {

// Interrupt blocking operations.

#ifdef BRPC_BTHREAD_TRACER

pthread_kill(worker, _task_tracer.get_trace_signal());

#else

interrupt_pthread(worker);

#endif // BRPC_BTHREAD_TRACER

}

// Join workers

for (auto worker : _workers) {

pthread_join(worker, nullptr);

}

TaskControl::~TaskControl() {

// NOTE: g_task_control is not destructed now because the situation

// is extremely racy.

delete _pending_time.exchange(nullptr, butil::memory_order_relaxed);

_worker_usage_second.hide();

_switch_per_second.hide();

_signal_per_second.hide();

_status.hide();

stop_and_join();

}

int TaskControl::_add_group(TaskGroup* g, bthread_tag_t tag) {

if (__builtin_expect(nullptr == g, 0)) {

return -1;

}

std::unique_lock<butil::Mutex> mu(_modify_group_mutex);

if (_stop) {

return -1;

}

g->set_tag(tag);

g->set_pl(&_tagged_pl[tag][butil::fmix64(pthread_numeric_id()) % _pl_num_of_each_tag]);

size_t ngroup = _tagged_ngroup[tag].load(butil::memory_order_relaxed);

if (ngroup < (size_t)BTHREAD_MAX_CONCURRENCY) {

_tagged_groups[tag][ngroup] = g;

_tagged_ngroup[tag].store(ngroup + 1, butil::memory_order_release);

}

mu.unlock();

// See the comments in _destroy_group

// TODO: Not needed anymore since non-worker pthread cannot have TaskGroup

// signal_task(65536, tag);

return 0;

}

void TaskControl::delete_task_group(void* arg) {

delete(TaskGroup*)arg;

}

int TaskControl::_destroy_group(TaskGroup* g) {

if (nullptr == g) {

LOG(ERROR) << "Param[g] is NULL";

return -1;

}

if (g->_control != this) {

LOG(ERROR) << "TaskGroup=" << g

<< " does not belong to this TaskControl=" << this;

return -1;

}

bool erased = false;

{

BAIDU_SCOPED_LOCK(_modify_group_mutex);

auto tag = g->tag();

auto& groups = tag_group(tag);

const size_t ngroup = tag_ngroup(tag).load(butil::memory_order_relaxed);

for (size_t i = 0; i < ngroup; ++i) {

if (groups[i] == g) {

// No need for atomic_thread_fence because lock did it.

groups[i] = groups[ngroup - 1];

// Change _ngroup and keep _groups unchanged at last so that:

// - If steal_task sees the newest _ngroup, it would not touch

// _groups[ngroup -1]

// - If steal_task sees old _ngroup and is still iterating on

// _groups, it would not miss _groups[ngroup - 1] which was

// swapped to _groups[i]. Although adding new group would

// overwrite it, since we do signal_task in _add_group(),

// we think the pending tasks of _groups[ngroup - 1] would

// not miss.

tag_ngroup(tag).store(ngroup - 1, butil::memory_order_release);

//_groups[ngroup - 1] = nullptr;

erased = true;

break;

}

// Can't delete g immediately because for performance consideration,

// we don't lock _modify_group_mutex in steal_task which may

// access the removed group concurrently. We use simple strategy here:

// Schedule a function which deletes the TaskGroup after

// FLAGS_task_group_delete_delay seconds

if (erased) {

get_global_timer_thread()->schedule(

delete_task_group, g,

butil::microseconds_from_now(FLAGS_task_group_delete_delay * 1000000L));

}

return 0;

}

bool TaskControl::steal_task(bthread_t* tid, size_t* seed, size_t offset) {

auto tag = BAIDU_GET_VOLATILE_THREAD_LOCAL(tls_task_group)->tag();

if (_enable_priority_queue) {

for (int i = 0;

i < _ed_priority_queue_num_of_each_tag; ++i) {

if (ed_priority_queue(tag, i).steal(tid)) {

return true;

}

// 1: Acquiring fence is paired with releasing fence in _add_group to

// avoid accessing uninitialized slot of _groups.

const size_t ngroup = tag_ngroup(tag).load(butil::memory_order_acquire/*1*/);

if (0 == ngroup) {

return false;

}

// NOTE: Don't return inside `for' iteration since we need to update |seed|

bool stolen = false;

size_t s = *seed;

auto& groups = tag_group(tag);

for (size_t i = 0; i < ngroup; ++i, s += offset) {

TaskGroup* g = groups[s % ngroup];

// g is possibly nullptr because of concurrent _destroy_group

if (g) {

if (g->_rq.steal(tid)) {

stolen = true;

break;

}

if (g->_remote_rq.pop(tid)) {

stolen = true;

break;

}

*seed = s;

return stolen;

}

void TaskControl::signal_task(int num_task, bthread_tag_t tag) {

if (num_task <= 0) {

return;

}

// TODO(gejun): Current algorithm does not guarantee enough threads will

// be created to match caller's requests. But in another side, there's also

// many useless signalings according to current impl. Capping the concurrency

// is a good balance between performance and timeliness of scheduling.

if (num_task > 2) {

num_task = 2;

}

auto& pl = tag_pl(tag);

size_t start_index = butil::fmix64(pthread_numeric_id()) % _pl_num_of_each_tag;

for (size_t i = 0; i < _pl_num_of_each_tag && num_task > 0; ++i) {

num_task -= pl[start_index].signal(1);

if (++start_index >= _pl_num_of_each_tag) {

start_index = 0;

}

if (num_task > 0 &&

FLAGS_bthread_min_concurrency > 0 && // test min_concurrency for performance

_concurrency.load(butil::memory_order_relaxed) < FLAGS_bthread_concurrency) {

// TODO: Reduce this lock

BAIDU_SCOPED_LOCK(g_task_control_mutex);

if (_concurrency.load(butil::memory_order_acquire) < FLAGS_bthread_concurrency) {

add_workers(1, tag);

}

void TaskControl::print_rq_sizes(std::ostream& os) {

size_t ngroup = 0;

std::for_each(_tagged_ngroup.begin(), _tagged_ngroup.end(), [&](butil::atomic<size_t>& index) {

ngroup += index.load(butil::memory_order_relaxed);

});

DEFINE_SMALL_ARRAY(int, nums, ngroup, 128);

{

BAIDU_SCOPED_LOCK(_modify_group_mutex);

// ngroup > _ngroup: nums[_ngroup ... ngroup-1] = 0

// ngroup < _ngroup: just ignore _groups[_ngroup ... ngroup-1]

int i = 0;

for_each_task_group([&](TaskGroup* g) {

nums[i] = (g ? g->_rq.volatile_size() : 0);

++i;

});

}

for (size_t i = 0; i < ngroup; ++i) {

os << nums[i] << ' ';

}

double TaskControl::get_cumulated_worker_time() {

int64_t cputime_ns = 0;

BAIDU_SCOPED_LOCK(_modify_group_mutex);

for_each_task_group([&](TaskGroup* g) {

cputime_ns += g->cumulated_cputime_ns();

});

return cputime_ns / 1000000000.0;

}

double TaskControl::get_cumulated_worker_time(bthread_tag_t tag) {

int64_t cputime_ns = 0;

BAIDU_SCOPED_LOCK(_modify_group_mutex);

const size_t ngroup = tag_ngroup(tag).load(butil::memory_order_relaxed);

auto& groups = tag_group(tag);

for (size_t i = 0; i < ngroup; ++i) {

cputime_ns += groups[i]->cumulated_cputime_ns();

}

return cputime_ns / 1000000000.0;

}

int64_t TaskControl::get_cumulated_switch_count() {

int64_t c = 0;

BAIDU_SCOPED_LOCK(_modify_group_mutex);

for_each_task_group([&](TaskGroup* g) {

if (g) {

c += g->_nswitch;

}

});

return c;

}

int64_t TaskControl::get_cumulated_signal_count() {

int64_t c = 0;

BAIDU_SCOPED_LOCK(_modify_group_mutex);

for_each_task_group([&](TaskGroup* g) {

if (g) {

c += g->_nsignaled + g->_remote_nsignaled;

}

});

return c;

}

bvar::LatencyRecorder* TaskControl::create_exposed_pending_time() {

bool is_creator = false;

_pending_time_mutex.lock();

bvar::LatencyRecorder* pt = _pending_time.load(butil::memory_order_consume);

if (!pt) {

pt = new bvar::LatencyRecorder;

_pending_time.store(pt, butil::memory_order_release);

is_creator = true;

}

_pending_time_mutex.unlock();

if (is_creator) {

pt->expose("bthread_creation");

}

return pt;

}

std::vector<bthread_t> TaskControl::get_living_bthreads() {

std::vector<bthread_t> living_bthread_ids;

living_bthread_ids.reserve(1024);

butil::for_each_resource<TaskMeta>([&living_bthread_ids](TaskMeta* m) {

// filter out those bthreads created by bthread_start* functions,

// i.e. not those created internally to run main task as they are

// opaque to user.

if (m && m->fn) {

// determine whether the bthread is living by checking version

const uint32_t given_ver = get_version(m->tid);

BAIDU_SCOPED_LOCK(m->version_lock);

if (given_ver == *m->version_butex) {

living_bthread_ids.push_back(m->tid);

}

});

return living_bthread_ids;

}

} // namespace bthread

brpc/src/bthread/task_control.cpp at master · apache/brpc · GitHub

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