/** * Removes the specified set of session ids from the persistent sessions collection and returns the * number of sessions actually removed. */ int removeSessionsRecords(OperationContext* opCtx, SessionsCollection& sessionsCollection, const LogicalSessionIdSet& sessionIdsToRemove) { if (sessionIdsToRemove.empty()) { return 0; } Locker* locker = opCtx->lockState(); Locker::LockSnapshot snapshot; invariant(locker->saveLockStateAndUnlock(&snapshot)); const auto guard = MakeGuard([&] { UninterruptibleLockGuard noInterrupt(opCtx->lockState()); locker->restoreLockState(opCtx, snapshot); }); // Top-level locks are freed, release any potential low-level (storage engine-specific // locks). If we are yielding, we are at a safe place to do so. opCtx->recoveryUnit()->abandonSnapshot(); // Track the number of yields in CurOp. CurOp::get(opCtx)->yielded(); auto removed = uassertStatusOK(sessionsCollection.findRemovedSessions(opCtx, sessionIdsToRemove)); uassertStatusOK(sessionsCollection.removeTransactionRecords(opCtx, removed)); return removed.size(); }
// static void QueryYield::yieldAllLocks(OperationContext* txn, RecordFetcher* fetcher, const std::string& planExecNS) { // Things have to happen here in a specific order: // 1) Tell the RecordFetcher to do any setup which needs to happen inside locks // 2) Release lock mgr locks // 3) Go to sleep // 4) Touch the record we're yielding on, if there is one (RecordFetcher::fetch) // 5) Reacquire lock mgr locks Locker* locker = txn->lockState(); Locker::LockSnapshot snapshot; if (fetcher) { fetcher->setup(); } // Nothing was unlocked, just return, yielding is pointless. if (!locker->saveLockStateAndUnlock(&snapshot)) { return; } // Top-level locks are freed, release any potential low-level (storage engine-specific // locks). If we are yielding, we are at a safe place to do so. txn->recoveryUnit()->abandonSnapshot(); MONGO_FAIL_POINT_BLOCK(setYieldAllLocksWait, customWait) { const BSONObj& data = customWait.getData(); BSONElement customWaitNS = data["namespace"]; if (!customWaitNS || planExecNS == customWaitNS.str()) { sleepFor(stdx::chrono::milliseconds(data["waitForMillis"].numberInt())); } } // Track the number of yields in CurOp. CurOp::get(txn)->yielded(); if (fetcher) { fetcher->fetch(); } locker->restoreLockState(snapshot); }