SERVER-37299 Remove dependency on s/grid from rw_concern_d.

Read concern implementation shim'd out and separate for mongod and embedded.

1 files changed, 2 insertions, 358 deletions

diff --git a/src/mongo/db/read_concern.cpp b/src/mongo/db/read_concern.cpp
index d2f18637fac..82dce5ac8c8 100644
--- a/src/mongo/db/read_concern.cpp
+++ b/src/mongo/db/read_concern.cpp
@@ -26,367 +26,11 @@
  *    it in the license file.
  */
 
-#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kCommand
-
-#include "mongo/platform/basic.h"
-
 #include "mongo/db/read_concern.h"
 
-#include "mongo/base/status.h"
-#include "mongo/base/status_with.h"
-#include "mongo/db/commands.h"
-#include "mongo/db/concurrency/d_concurrency.h"
-#include "mongo/db/concurrency/write_conflict_exception.h"
-#include "mongo/db/curop.h"
-#include "mongo/db/logical_clock.h"
-#include "mongo/db/op_observer.h"
-#include "mongo/db/operation_context.h"
-#include "mongo/db/repl/read_concern_args.h"
-#include "mongo/db/repl/repl_client_info.h"
-#include "mongo/db/repl/replication_coordinator.h"
-#include "mongo/db/s/sharding_state.h"
-#include "mongo/db/server_options.h"
-#include "mongo/db/server_parameters.h"
-#include "mongo/db/transaction_participant.h"
-#include "mongo/s/client/shard_registry.h"
-#include "mongo/s/grid.h"
-#include "mongo/util/log.h"
-
 namespace mongo {
-namespace {
-
-/**
- *  Synchronize writeRequests
- */
-
-class WriteRequestSynchronizer;
-const auto getWriteRequestsSynchronizer =
-    ServiceContext::declareDecoration<WriteRequestSynchronizer>();
-
-class WriteRequestSynchronizer {
-public:
-    WriteRequestSynchronizer() = default;
-
-    /**
-     * Returns a tuple <false, existingWriteRequest> if it can  find the one that happened after or
-     * at clusterTime.
-     * Returns a tuple <true, newWriteRequest> otherwise.
-     */
-    std::tuple<bool, std::shared_ptr<Notification<Status>>> getOrCreateWriteRequest(
-        LogicalTime clusterTime) {
-        stdx::unique_lock<stdx::mutex> lock(_mutex);
-        auto lastEl = _writeRequests.rbegin();
-        if (lastEl != _writeRequests.rend() && lastEl->first >= clusterTime.asTimestamp()) {
-            return std::make_tuple(false, lastEl->second);
-        } else {
-            auto newWriteRequest = std::make_shared<Notification<Status>>();
-            _writeRequests[clusterTime.asTimestamp()] = newWriteRequest;
-            return std::make_tuple(true, newWriteRequest);
-        }
-    }
-
-    /**
-     * Erases writeRequest that happened at clusterTime
-     */
-    void deleteWriteRequest(LogicalTime clusterTime) {
-        stdx::unique_lock<stdx::mutex> lock(_mutex);
-        auto el = _writeRequests.find(clusterTime.asTimestamp());
-        invariant(el != _writeRequests.end());
-        invariant(el->second);
-        el->second.reset();
-        _writeRequests.erase(el);
-    }
-
-private:
-    stdx::mutex _mutex;
-    std::map<Timestamp, std::shared_ptr<Notification<Status>>> _writeRequests;
-};
-
-
-MONGO_EXPORT_SERVER_PARAMETER(waitForSecondaryBeforeNoopWriteMS, int, 10);
-
-/**
- *  Schedule a write via appendOplogNote command to the primary of this replica set.
- */
-Status makeNoopWriteIfNeeded(OperationContext* opCtx, LogicalTime clusterTime) {
-    repl::ReplicationCoordinator* const replCoord = repl::ReplicationCoordinator::get(opCtx);
-    invariant(replCoord->isReplEnabled());
-
-    auto& writeRequests = getWriteRequestsSynchronizer(opCtx->getClient()->getServiceContext());
-
-    auto lastAppliedOpTime = LogicalTime(replCoord->getMyLastAppliedOpTime().getTimestamp());
-
-    // secondaries may lag primary so wait first to avoid unnecessary noop writes.
-    if (clusterTime > lastAppliedOpTime && replCoord->getMemberState().secondary()) {
-        auto deadline = Date_t::now() + Milliseconds(waitForSecondaryBeforeNoopWriteMS.load());
-        auto readConcernArgs =
-            repl::ReadConcernArgs(clusterTime, repl::ReadConcernLevel::kLocalReadConcern);
-        auto waitStatus = replCoord->waitUntilOpTimeForReadUntil(opCtx, readConcernArgs, deadline);
-        lastAppliedOpTime = LogicalTime(replCoord->getMyLastAppliedOpTime().getTimestamp());
-        if (!waitStatus.isOK()) {
-            LOG(1) << "Wait for clusterTime: " << clusterTime.toString()
-                   << " until deadline: " << deadline << " failed with " << waitStatus.toString();
-        }
-    }
-
-    auto status = Status::OK();
-    int remainingAttempts = 3;
-    // this loop addresses the case when two or more threads need to advance the opLog time but the
-    // one that waits for the notification gets the later clusterTime, so when the request finishes
-    // it needs to be repeated with the later time.
-    while (clusterTime > lastAppliedOpTime) {
-        auto shardingState = ShardingState::get(opCtx);
-        // standalone replica set, so there is no need to advance the OpLog on the primary.
-        if (!shardingState->enabled()) {
-            return Status::OK();
-        }
-
-        auto myShard = Grid::get(opCtx)->shardRegistry()->getShard(opCtx, shardingState->shardId());
-        if (!myShard.isOK()) {
-            return myShard.getStatus();
-        }
-
-        if (!remainingAttempts--) {
-            std::stringstream ss;
-            ss << "Requested clusterTime " << clusterTime.toString()
-               << " is greater than the last primary OpTime: " << lastAppliedOpTime.toString()
-               << " no retries left";
-            return Status(ErrorCodes::InternalError, ss.str());
-        }
-
-        auto myWriteRequest = writeRequests.getOrCreateWriteRequest(clusterTime);
-        if (std::get<0>(myWriteRequest)) {  // Its a new request
-            try {
-                LOG(2) << "New appendOplogNote request on clusterTime: " << clusterTime.toString()
-                       << " remaining attempts: " << remainingAttempts;
-                auto swRes = myShard.getValue()->runCommand(
-                    opCtx,
-                    ReadPreferenceSetting(ReadPreference::PrimaryOnly),
-                    "admin",
-                    BSON("appendOplogNote" << 1 << "maxClusterTime" << clusterTime.asTimestamp()
-                                           << "data"
-                                           << BSON("noop write for afterClusterTime read concern"
-                                                   << 1)),
-                    Shard::RetryPolicy::kIdempotent);
-                status = swRes.getStatus();
-                std::get<1>(myWriteRequest)->set(status);
-                writeRequests.deleteWriteRequest(clusterTime);
-            } catch (const DBException& ex) {
-                status = ex.toStatus();
-                // signal the writeRequest to unblock waiters
-                std::get<1>(myWriteRequest)->set(status);
-                writeRequests.deleteWriteRequest(clusterTime);
-            }
-        } else {
-            LOG(2) << "Join appendOplogNote request on clusterTime: " << clusterTime.toString()
-                   << " remaining attempts: " << remainingAttempts;
-            try {
-                status = std::get<1>(myWriteRequest)->get(opCtx);
-            } catch (const DBException& ex) {
-                return ex.toStatus();
-            }
-        }
-        // If the write status is ok need to wait for the oplog to replicate.
-        if (status.isOK()) {
-            return status;
-        }
-        lastAppliedOpTime = LogicalTime(replCoord->getMyLastAppliedOpTime().getTimestamp());
-    }
-    // This is when the noop write failed but the opLog caught up to clusterTime by replicating.
-    if (!status.isOK()) {
-        LOG(1) << "Reached clusterTime " << lastAppliedOpTime.toString()
-               << " but failed noop write due to " << status.toString();
-    }
-    return Status::OK();
-}
-}  // namespace
-
-Status waitForReadConcern(OperationContext* opCtx,
-                          const repl::ReadConcernArgs& readConcernArgs,
-                          bool allowAfterClusterTime) {
-    // If we are in a direct client within a transaction, then we may be holding locks, so it is
-    // illegal to wait for read concern. This is fine, since the outer operation should have handled
-    // waiting for read concern. We don't want to ignore prepare conflicts because snapshot reads
-    // should block on prepared transactions.
-    auto txnParticipant = TransactionParticipant::get(opCtx);
-    if (opCtx->getClient()->isInDirectClient() && txnParticipant &&
-        txnParticipant->inMultiDocumentTransaction()) {
-        opCtx->recoveryUnit()->setIgnorePrepared(false);
-        return Status::OK();
-    }
-
-    repl::ReplicationCoordinator* const replCoord = repl::ReplicationCoordinator::get(opCtx);
-    invariant(replCoord);
-
-    // Currently speculative read concern is used only for transactions. However, speculative read
-    // concern is not yet supported with atClusterTime.
-    //
-    // TODO SERVER-34620: Re-enable speculative behavior when "atClusterTime" is specified.
-    const bool speculative = txnParticipant && txnParticipant->inMultiDocumentTransaction() &&
-        !readConcernArgs.getArgsAtClusterTime();
-
-    if (readConcernArgs.getLevel() == repl::ReadConcernLevel::kLinearizableReadConcern) {
-        if (replCoord->getReplicationMode() != repl::ReplicationCoordinator::modeReplSet) {
-            // For standalone nodes, Linearizable Read is not supported.
-            return {ErrorCodes::NotAReplicaSet,
-                    "node needs to be a replica set member to use read concern"};
-        }
-
-        if (readConcernArgs.getArgsOpTime()) {
-            return {ErrorCodes::FailedToParse,
-                    "afterOpTime not compatible with linearizable read concern"};
-        }
-
-        if (!replCoord->getMemberState().primary()) {
-            return {ErrorCodes::NotMaster,
-                    "cannot satisfy linearizable read concern on non-primary node"};
-        }
-    }
-
-    auto afterClusterTime = readConcernArgs.getArgsAfterClusterTime();
-    auto atClusterTime = readConcernArgs.getArgsAtClusterTime();
-
-    if (afterClusterTime) {
-        if (!allowAfterClusterTime) {
-            return {ErrorCodes::InvalidOptions, "afterClusterTime is not allowed for this command"};
-        }
-    }
-
-    if (!readConcernArgs.isEmpty()) {
-        invariant(!afterClusterTime || !atClusterTime);
-        auto targetClusterTime = afterClusterTime ? afterClusterTime : atClusterTime;
-
-        if (targetClusterTime) {
-            std::string readConcernName = afterClusterTime ? "afterClusterTime" : "atClusterTime";
-
-            if (!replCoord->isReplEnabled()) {
-                return {ErrorCodes::IllegalOperation,
-                        str::stream() << "Cannot specify " << readConcernName
-                                      << " readConcern without replication enabled"};
-            }
-
-            auto currentTime = LogicalClock::get(opCtx)->getClusterTime();
-            if (currentTime < *targetClusterTime) {
-                return {ErrorCodes::InvalidOptions,
-                        str::stream() << "readConcern " << readConcernName
-                                      << " value must not be greater than the current clusterTime. "
-                                         "Requested clusterTime: "
-                                      << targetClusterTime->toString()
-                                      << "; current clusterTime: "
-                                      << currentTime.toString()};
-            }
-
-            auto status = makeNoopWriteIfNeeded(opCtx, *targetClusterTime);
-            if (!status.isOK()) {
-                LOG(0) << "Failed noop write at clusterTime: " << targetClusterTime->toString()
-                       << " due to " << status.toString();
-            }
-        }
-
-        if (replCoord->isReplEnabled() || !afterClusterTime) {
-            auto status = replCoord->waitUntilOpTimeForRead(opCtx, readConcernArgs);
-            if (!status.isOK()) {
-                return status;
-            }
-        }
-    }
-
-    if (readConcernArgs.getLevel() == repl::ReadConcernLevel::kSnapshotReadConcern) {
-        if (replCoord->getReplicationMode() != repl::ReplicationCoordinator::modeReplSet) {
-            return {ErrorCodes::NotAReplicaSet,
-                    "node needs to be a replica set member to use readConcern: snapshot"};
-        }
-        if (speculative) {
-            txnParticipant->setSpeculativeTransactionOpTime(
-                opCtx,
-                readConcernArgs.getOriginalLevel() == repl::ReadConcernLevel::kSnapshotReadConcern
-                    ? SpeculativeTransactionOpTime::kAllCommitted
-                    : SpeculativeTransactionOpTime::kLastApplied);
-        }
-    }
-
-    if (atClusterTime) {
-        opCtx->recoveryUnit()->setIgnorePrepared(false);
-
-        // TODO(SERVER-34620): We should be using Session::setSpeculativeTransactionReadOpTime when
-        // doing speculative execution with atClusterTime.
-        opCtx->recoveryUnit()->setTimestampReadSource(RecoveryUnit::ReadSource::kProvided,
-                                                      atClusterTime->asTimestamp());
-        return Status::OK();
-    }
-
-    if ((readConcernArgs.getLevel() == repl::ReadConcernLevel::kMajorityReadConcern ||
-         readConcernArgs.getLevel() == repl::ReadConcernLevel::kSnapshotReadConcern) &&
-        !speculative &&
-        replCoord->getReplicationMode() == repl::ReplicationCoordinator::Mode::modeReplSet) {
-
-        const int debugLevel = serverGlobalParams.clusterRole == ClusterRole::ConfigServer ? 1 : 2;
-
-        LOG(debugLevel) << "Waiting for 'committed' snapshot to be available for reading: "
-                        << readConcernArgs;
-
-        opCtx->recoveryUnit()->setTimestampReadSource(RecoveryUnit::ReadSource::kMajorityCommitted);
-        Status status = opCtx->recoveryUnit()->obtainMajorityCommittedSnapshot();
-
-        // Wait until a snapshot is available.
-        while (status == ErrorCodes::ReadConcernMajorityNotAvailableYet) {
-            LOG(debugLevel) << "Snapshot not available yet.";
-            replCoord->waitUntilSnapshotCommitted(opCtx, Timestamp());
-            status = opCtx->recoveryUnit()->obtainMajorityCommittedSnapshot();
-        }
-
-        if (!status.isOK()) {
-            return status;
-        }
-
-        LOG(debugLevel) << "Using 'committed' snapshot: " << CurOp::get(opCtx)->opDescription();
-    }
-
-    // Only snapshot, linearizable and afterClusterTime reads should block on prepared transactions.
-    if (readConcernArgs.getLevel() != repl::ReadConcernLevel::kSnapshotReadConcern &&
-        readConcernArgs.getLevel() != repl::ReadConcernLevel::kLinearizableReadConcern &&
-        !afterClusterTime && !atClusterTime) {
-        opCtx->recoveryUnit()->setIgnorePrepared(true);
-    } else {
-        opCtx->recoveryUnit()->setIgnorePrepared(false);
-    }
-
-    return Status::OK();
-}
-
-Status waitForLinearizableReadConcern(OperationContext* opCtx) {
-
-    repl::ReplicationCoordinator* replCoord =
-        repl::ReplicationCoordinator::get(opCtx->getClient()->getServiceContext());
-
-    {
-        Lock::DBLock lk(opCtx, "local", MODE_IX);
-        Lock::CollectionLock lock(opCtx->lockState(), "local.oplog.rs", MODE_IX);
-
-        if (!replCoord->canAcceptWritesForDatabase(opCtx, "admin")) {
-            return {ErrorCodes::NotMaster,
-                    "No longer primary when waiting for linearizable read concern"};
-        }
-
-        writeConflictRetry(opCtx, "waitForLinearizableReadConcern", "local.rs.oplog", [&opCtx] {
-            WriteUnitOfWork uow(opCtx);
-            opCtx->getClient()->getServiceContext()->getOpObserver()->onOpMessage(
-                opCtx,
-                BSON("msg"
-                     << "linearizable read"));
-            uow.commit();
-        });
-    }
-    WriteConcernOptions wc = WriteConcernOptions(
-        WriteConcernOptions::kMajority, WriteConcernOptions::SyncMode::UNSET, 0);
 
-    repl::OpTime lastOpApplied = repl::ReplClientInfo::forClient(opCtx->getClient()).getLastOp();
-    auto awaitReplResult = replCoord->awaitReplication(opCtx, lastOpApplied, wc);
-    if (awaitReplResult.status == ErrorCodes::WriteConcernFailed) {
-        return Status(ErrorCodes::LinearizableReadConcernError,
-                      "Failed to confirm that read was linearizable.");
-    }
-    return awaitReplResult.status;
-}
+MONGO_DEFINE_SHIM(waitForReadConcern);
+MONGO_DEFINE_SHIM(waitForLinearizableReadConcern);
 
 }  // namespace mongo