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/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/platform/basic.h"
#include "mongo/util/periodic_runner_impl.h"
#include "mongo/base/error_codes.h"
#include "mongo/db/client.h"
#include "mongo/db/service_context.h"
#include "mongo/logv2/log.h"
#include "mongo/util/assert_util.h"
#include "mongo/util/clock_source.h"
#include "mongo/util/scopeguard.h"
#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kDefault
namespace mongo {
PeriodicRunnerImpl::PeriodicRunnerImpl(ServiceContext* svc, ClockSource* clockSource)
: _svc(svc), _clockSource(clockSource) {}
auto PeriodicRunnerImpl::makeJob(PeriodicJob job) -> JobAnchor {
auto impl = std::make_shared<PeriodicJobImpl>(std::move(job), this->_clockSource, this->_svc);
JobAnchor anchor(std::move(impl));
return anchor;
}
PeriodicRunnerImpl::PeriodicJobImpl::PeriodicJobImpl(PeriodicJob job,
ClockSource* source,
ServiceContext* svc)
: _job(std::move(job)), _clockSource(source), _serviceContext(svc), _client(nullptr) {}
void PeriodicRunnerImpl::PeriodicJobImpl::_run() {
{
stdx::lock_guard lk(_mutex);
if (MONGO_unlikely(_execStatus == ExecutionStatus::CANCELED))
uasserted(ErrorCodes::PeriodicJobIsStopped,
"Attempted to start an already stopped job");
invariant(_execStatus == ExecutionStatus::NOT_SCHEDULED);
}
auto [startPromise, startFuture] = makePromiseFuture<void>();
_thread = stdx::thread([this, startPromise = std::move(startPromise)]() mutable {
ON_BLOCK_EXIT([this] { _stopPromise.emplaceValue(); });
ThreadClient client(_job.name, _serviceContext, nullptr);
if (!_job.isKillableByStepdown) {
stdx::lock_guard<Client> lk(*client.get());
client.get()->setSystemOperationUnkillableByStepdown(lk);
}
{
// This ensures client object is not destructed so long as others can access it.
ON_BLOCK_EXIT([this] {
stdx::lock_guard lk(_mutex);
_client = nullptr;
});
// Let start() know we're running
{
stdx::lock_guard lk(_mutex);
_client = client.get();
_execStatus = PeriodicJobImpl::ExecutionStatus::RUNNING;
}
startPromise.emplaceValue();
stdx::unique_lock<Latch> lk(_mutex);
while (_execStatus != ExecutionStatus::CANCELED) {
// Wait until it's unpaused or canceled
_condvar.wait(lk, [&] { return _execStatus != ExecutionStatus::PAUSED; });
if (_execStatus == ExecutionStatus::CANCELED) {
return;
}
auto start = _clockSource->now();
// Unlock while job is running so we can pause/cancel concurrently
lk.unlock();
_job.job(client.get());
lk.lock();
auto getDeadlineFromInterval = [&] {
return start + _job.interval;
};
do {
auto deadline = getDeadlineFromInterval();
if (_clockSource->waitForConditionUntil(_condvar, lk, deadline, [&] {
return _execStatus == ExecutionStatus::CANCELED ||
getDeadlineFromInterval() != deadline;
})) {
if (_execStatus == ExecutionStatus::CANCELED) {
return;
}
}
} while (_clockSource->now() < getDeadlineFromInterval());
}
}
});
// Wait for the thread to actually start
startFuture.get();
}
void PeriodicRunnerImpl::PeriodicJobImpl::start() {
LOGV2_DEBUG(23323, 2, "Starting periodic job {job_name}", "job_name"_attr = _job.name);
_run();
}
void PeriodicRunnerImpl::PeriodicJobImpl::pause() {
stdx::lock_guard<Latch> lk(_mutex);
if (MONGO_unlikely(_execStatus == ExecutionStatus::CANCELED))
uasserted(ErrorCodes::PeriodicJobIsStopped, "Attempted to pause an already stopped job");
invariant(_execStatus == PeriodicJobImpl::ExecutionStatus::RUNNING);
_execStatus = PeriodicJobImpl::ExecutionStatus::PAUSED;
}
void PeriodicRunnerImpl::PeriodicJobImpl::resume() {
{
stdx::lock_guard<Latch> lk(_mutex);
if (MONGO_unlikely(_execStatus == ExecutionStatus::CANCELED))
uasserted(ErrorCodes::PeriodicJobIsStopped,
"Attempted to resume an already stopped job");
invariant(_execStatus == PeriodicJobImpl::ExecutionStatus::PAUSED);
_execStatus = PeriodicJobImpl::ExecutionStatus::RUNNING;
}
_condvar.notify_one();
}
void PeriodicRunnerImpl::PeriodicJobImpl::stop() {
auto lastExecStatus = [&] {
stdx::lock_guard<Latch> lk(_mutex);
return std::exchange(_execStatus, ExecutionStatus::CANCELED);
}();
// If we never started, then nobody should wait
if (lastExecStatus == ExecutionStatus::NOT_SCHEDULED) {
return;
}
auto stopFuture = _stopPromise.getFuture();
// Only join once
if (lastExecStatus != ExecutionStatus::CANCELED) {
LOGV2_DEBUG(23324, 2, "Stopping periodic job {job_name}", "job_name"_attr = _job.name);
_condvar.notify_one();
// Kill the client thread and its opCtx (if any) before joining.
// So long as `_job` returns upon receiving the kill signal, the following ensures liveness
// (i.e., this method will eventually return).
if (!stopFuture.isReady()) {
stdx::lock_guard<Latch> lk(_mutex);
// Check if the client thread has already returned.
if (_client) {
_client->setKilled();
}
}
_thread.join();
}
stopFuture.get();
}
Milliseconds PeriodicRunnerImpl::PeriodicJobImpl::getPeriod() {
stdx::lock_guard<Latch> lk(_mutex);
return _job.interval;
}
void PeriodicRunnerImpl::PeriodicJobImpl::setPeriod(Milliseconds ms) {
stdx::lock_guard<Latch> lk(_mutex);
_job.interval = ms;
if (_execStatus == PeriodicJobImpl::ExecutionStatus::RUNNING) {
_condvar.notify_one();
}
}
} // namespace mongo
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