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/**
* Copyright (C) 2014 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* 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 GNU Affero General 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.
*/
#pragma once
#include <string>
namespace mongo {
class OperationContext;
class RecordFetcher;
/**
* See the documentation for yieldAllLocks(...).
*/
class QueryYield {
QueryYield();
public:
/**
* If not in a nested context, unlocks all locks, suggests to the operating system to
* switch to another thread, and then reacquires all locks.
*
* If in a nested context (eg DBDirectClient), does nothing.
*/
static void yieldAllLocks(OperationContext* txn,
RecordFetcher* fetcher,
const std::string& planExecNS);
};
} // namespace mongo
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