+++ /dev/null
-// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
-// This source code is licensed under both the GPLv2 (found in the
-// COPYING file in the root directory) and Apache 2.0 License
-// (found in the LICENSE.Apache file in the root directory).
-
-#ifndef ROCKSDB_LITE
-
-#include "utilities/transactions/transaction_lock_mgr.h"
-
-#include <cinttypes>
-
-#include <algorithm>
-#include <condition_variable>
-#include <functional>
-#include <mutex>
-#include <string>
-#include <vector>
-
-#include "monitoring/perf_context_imp.h"
-#include "rocksdb/slice.h"
-#include "rocksdb/utilities/transaction_db_mutex.h"
-#include "test_util/sync_point.h"
-#include "util/cast_util.h"
-#include "util/hash.h"
-#include "util/thread_local.h"
-#include "utilities/transactions/pessimistic_transaction_db.h"
-
-namespace ROCKSDB_NAMESPACE {
-
-struct LockInfo {
- bool exclusive;
- autovector<TransactionID> txn_ids;
-
- // Transaction locks are not valid after this time in us
- uint64_t expiration_time;
-
- LockInfo(TransactionID id, uint64_t time, bool ex)
- : exclusive(ex), expiration_time(time) {
- txn_ids.push_back(id);
- }
- LockInfo(const LockInfo& lock_info)
- : exclusive(lock_info.exclusive),
- txn_ids(lock_info.txn_ids),
- expiration_time(lock_info.expiration_time) {}
-};
-
-struct LockMapStripe {
- explicit LockMapStripe(std::shared_ptr<TransactionDBMutexFactory> factory) {
- stripe_mutex = factory->AllocateMutex();
- stripe_cv = factory->AllocateCondVar();
- assert(stripe_mutex);
- assert(stripe_cv);
- }
-
- // Mutex must be held before modifying keys map
- std::shared_ptr<TransactionDBMutex> stripe_mutex;
-
- // Condition Variable per stripe for waiting on a lock
- std::shared_ptr<TransactionDBCondVar> stripe_cv;
-
- // Locked keys mapped to the info about the transactions that locked them.
- // TODO(agiardullo): Explore performance of other data structures.
- std::unordered_map<std::string, LockInfo> keys;
-};
-
-// Map of #num_stripes LockMapStripes
-struct LockMap {
- explicit LockMap(size_t num_stripes,
- std::shared_ptr<TransactionDBMutexFactory> factory)
- : num_stripes_(num_stripes) {
- lock_map_stripes_.reserve(num_stripes);
- for (size_t i = 0; i < num_stripes; i++) {
- LockMapStripe* stripe = new LockMapStripe(factory);
- lock_map_stripes_.push_back(stripe);
- }
- }
-
- ~LockMap() {
- for (auto stripe : lock_map_stripes_) {
- delete stripe;
- }
- }
-
- // Number of sepearate LockMapStripes to create, each with their own Mutex
- const size_t num_stripes_;
-
- // Count of keys that are currently locked in this column family.
- // (Only maintained if TransactionLockMgr::max_num_locks_ is positive.)
- std::atomic<int64_t> lock_cnt{0};
-
- std::vector<LockMapStripe*> lock_map_stripes_;
-
- size_t GetStripe(const std::string& key) const;
-};
-
-void DeadlockInfoBuffer::AddNewPath(DeadlockPath path) {
- std::lock_guard<std::mutex> lock(paths_buffer_mutex_);
-
- if (paths_buffer_.empty()) {
- return;
- }
-
- paths_buffer_[buffer_idx_] = std::move(path);
- buffer_idx_ = (buffer_idx_ + 1) % paths_buffer_.size();
-}
-
-void DeadlockInfoBuffer::Resize(uint32_t target_size) {
- std::lock_guard<std::mutex> lock(paths_buffer_mutex_);
-
- paths_buffer_ = Normalize();
-
- // Drop the deadlocks that will no longer be needed ater the normalize
- if (target_size < paths_buffer_.size()) {
- paths_buffer_.erase(
- paths_buffer_.begin(),
- paths_buffer_.begin() + (paths_buffer_.size() - target_size));
- buffer_idx_ = 0;
- }
- // Resize the buffer to the target size and restore the buffer's idx
- else {
- auto prev_size = paths_buffer_.size();
- paths_buffer_.resize(target_size);
- buffer_idx_ = (uint32_t)prev_size;
- }
-}
-
-std::vector<DeadlockPath> DeadlockInfoBuffer::Normalize() {
- auto working = paths_buffer_;
-
- if (working.empty()) {
- return working;
- }
-
- // Next write occurs at a nonexistent path's slot
- if (paths_buffer_[buffer_idx_].empty()) {
- working.resize(buffer_idx_);
- } else {
- std::rotate(working.begin(), working.begin() + buffer_idx_, working.end());
- }
-
- return working;
-}
-
-std::vector<DeadlockPath> DeadlockInfoBuffer::PrepareBuffer() {
- std::lock_guard<std::mutex> lock(paths_buffer_mutex_);
-
- // Reversing the normalized vector returns the latest deadlocks first
- auto working = Normalize();
- std::reverse(working.begin(), working.end());
-
- return working;
-}
-
-namespace {
-void UnrefLockMapsCache(void* ptr) {
- // Called when a thread exits or a ThreadLocalPtr gets destroyed.
- auto lock_maps_cache =
- static_cast<std::unordered_map<uint32_t, std::shared_ptr<LockMap>>*>(ptr);
- delete lock_maps_cache;
-}
-} // anonymous namespace
-
-TransactionLockMgr::TransactionLockMgr(
- TransactionDB* txn_db, size_t default_num_stripes, int64_t max_num_locks,
- uint32_t max_num_deadlocks,
- std::shared_ptr<TransactionDBMutexFactory> mutex_factory)
- : txn_db_impl_(nullptr),
- default_num_stripes_(default_num_stripes),
- max_num_locks_(max_num_locks),
- lock_maps_cache_(new ThreadLocalPtr(&UnrefLockMapsCache)),
- dlock_buffer_(max_num_deadlocks),
- mutex_factory_(mutex_factory) {
- assert(txn_db);
- txn_db_impl_ =
- static_cast_with_check<PessimisticTransactionDB, TransactionDB>(txn_db);
-}
-
-TransactionLockMgr::~TransactionLockMgr() {}
-
-size_t LockMap::GetStripe(const std::string& key) const {
- assert(num_stripes_ > 0);
- return fastrange64(GetSliceNPHash64(key), num_stripes_);
-}
-
-void TransactionLockMgr::AddColumnFamily(uint32_t column_family_id) {
- InstrumentedMutexLock l(&lock_map_mutex_);
-
- if (lock_maps_.find(column_family_id) == lock_maps_.end()) {
- lock_maps_.emplace(column_family_id,
- std::make_shared<LockMap>(default_num_stripes_, mutex_factory_));
- } else {
- // column_family already exists in lock map
- assert(false);
- }
-}
-
-void TransactionLockMgr::RemoveColumnFamily(uint32_t column_family_id) {
- // Remove lock_map for this column family. Since the lock map is stored
- // as a shared ptr, concurrent transactions can still keep using it
- // until they release their references to it.
- {
- InstrumentedMutexLock l(&lock_map_mutex_);
-
- auto lock_maps_iter = lock_maps_.find(column_family_id);
- assert(lock_maps_iter != lock_maps_.end());
-
- lock_maps_.erase(lock_maps_iter);
- } // lock_map_mutex_
-
- // Clear all thread-local caches
- autovector<void*> local_caches;
- lock_maps_cache_->Scrape(&local_caches, nullptr);
- for (auto cache : local_caches) {
- delete static_cast<LockMaps*>(cache);
- }
-}
-
-// Look up the LockMap std::shared_ptr for a given column_family_id.
-// Note: The LockMap is only valid as long as the caller is still holding on
-// to the returned std::shared_ptr.
-std::shared_ptr<LockMap> TransactionLockMgr::GetLockMap(
- uint32_t column_family_id) {
- // First check thread-local cache
- if (lock_maps_cache_->Get() == nullptr) {
- lock_maps_cache_->Reset(new LockMaps());
- }
-
- auto lock_maps_cache = static_cast<LockMaps*>(lock_maps_cache_->Get());
-
- auto lock_map_iter = lock_maps_cache->find(column_family_id);
- if (lock_map_iter != lock_maps_cache->end()) {
- // Found lock map for this column family.
- return lock_map_iter->second;
- }
-
- // Not found in local cache, grab mutex and check shared LockMaps
- InstrumentedMutexLock l(&lock_map_mutex_);
-
- lock_map_iter = lock_maps_.find(column_family_id);
- if (lock_map_iter == lock_maps_.end()) {
- return std::shared_ptr<LockMap>(nullptr);
- } else {
- // Found lock map. Store in thread-local cache and return.
- std::shared_ptr<LockMap>& lock_map = lock_map_iter->second;
- lock_maps_cache->insert({column_family_id, lock_map});
-
- return lock_map;
- }
-}
-
-// Returns true if this lock has expired and can be acquired by another
-// transaction.
-// If false, sets *expire_time to the expiration time of the lock according
-// to Env->GetMicros() or 0 if no expiration.
-bool TransactionLockMgr::IsLockExpired(TransactionID txn_id,
- const LockInfo& lock_info, Env* env,
- uint64_t* expire_time) {
- auto now = env->NowMicros();
-
- bool expired =
- (lock_info.expiration_time > 0 && lock_info.expiration_time <= now);
-
- if (!expired && lock_info.expiration_time > 0) {
- // return how many microseconds until lock will be expired
- *expire_time = lock_info.expiration_time;
- } else {
- for (auto id : lock_info.txn_ids) {
- if (txn_id == id) {
- continue;
- }
-
- bool success = txn_db_impl_->TryStealingExpiredTransactionLocks(id);
- if (!success) {
- expired = false;
- break;
- }
- *expire_time = 0;
- }
- }
-
- return expired;
-}
-
-Status TransactionLockMgr::TryLock(PessimisticTransaction* txn,
- uint32_t column_family_id,
- const std::string& key, Env* env,
- bool exclusive) {
- // Lookup lock map for this column family id
- std::shared_ptr<LockMap> lock_map_ptr = GetLockMap(column_family_id);
- LockMap* lock_map = lock_map_ptr.get();
- if (lock_map == nullptr) {
- char msg[255];
- snprintf(msg, sizeof(msg), "Column family id not found: %" PRIu32,
- column_family_id);
-
- return Status::InvalidArgument(msg);
- }
-
- // Need to lock the mutex for the stripe that this key hashes to
- size_t stripe_num = lock_map->GetStripe(key);
- assert(lock_map->lock_map_stripes_.size() > stripe_num);
- LockMapStripe* stripe = lock_map->lock_map_stripes_.at(stripe_num);
-
- LockInfo lock_info(txn->GetID(), txn->GetExpirationTime(), exclusive);
- int64_t timeout = txn->GetLockTimeout();
-
- return AcquireWithTimeout(txn, lock_map, stripe, column_family_id, key, env,
- timeout, std::move(lock_info));
-}
-
-// Helper function for TryLock().
-Status TransactionLockMgr::AcquireWithTimeout(
- PessimisticTransaction* txn, LockMap* lock_map, LockMapStripe* stripe,
- uint32_t column_family_id, const std::string& key, Env* env,
- int64_t timeout, LockInfo&& lock_info) {
- Status result;
- uint64_t end_time = 0;
-
- if (timeout > 0) {
- uint64_t start_time = env->NowMicros();
- end_time = start_time + timeout;
- }
-
- if (timeout < 0) {
- // If timeout is negative, we wait indefinitely to acquire the lock
- result = stripe->stripe_mutex->Lock();
- } else {
- result = stripe->stripe_mutex->TryLockFor(timeout);
- }
-
- if (!result.ok()) {
- // failed to acquire mutex
- return result;
- }
-
- // Acquire lock if we are able to
- uint64_t expire_time_hint = 0;
- autovector<TransactionID> wait_ids;
- result = AcquireLocked(lock_map, stripe, key, env, std::move(lock_info),
- &expire_time_hint, &wait_ids);
-
- if (!result.ok() && timeout != 0) {
- PERF_TIMER_GUARD(key_lock_wait_time);
- PERF_COUNTER_ADD(key_lock_wait_count, 1);
- // If we weren't able to acquire the lock, we will keep retrying as long
- // as the timeout allows.
- bool timed_out = false;
- do {
- // Decide how long to wait
- int64_t cv_end_time = -1;
-
- // Check if held lock's expiration time is sooner than our timeout
- if (expire_time_hint > 0 &&
- (timeout < 0 || (timeout > 0 && expire_time_hint < end_time))) {
- // expiration time is sooner than our timeout
- cv_end_time = expire_time_hint;
- } else if (timeout >= 0) {
- cv_end_time = end_time;
- }
-
- assert(result.IsBusy() || wait_ids.size() != 0);
-
- // We are dependent on a transaction to finish, so perform deadlock
- // detection.
- if (wait_ids.size() != 0) {
- if (txn->IsDeadlockDetect()) {
- if (IncrementWaiters(txn, wait_ids, key, column_family_id,
- lock_info.exclusive, env)) {
- result = Status::Busy(Status::SubCode::kDeadlock);
- stripe->stripe_mutex->UnLock();
- return result;
- }
- }
- txn->SetWaitingTxn(wait_ids, column_family_id, &key);
- }
-
- TEST_SYNC_POINT("TransactionLockMgr::AcquireWithTimeout:WaitingTxn");
- if (cv_end_time < 0) {
- // Wait indefinitely
- result = stripe->stripe_cv->Wait(stripe->stripe_mutex);
- } else {
- uint64_t now = env->NowMicros();
- if (static_cast<uint64_t>(cv_end_time) > now) {
- result = stripe->stripe_cv->WaitFor(stripe->stripe_mutex,
- cv_end_time - now);
- }
- }
-
- if (wait_ids.size() != 0) {
- txn->ClearWaitingTxn();
- if (txn->IsDeadlockDetect()) {
- DecrementWaiters(txn, wait_ids);
- }
- }
-
- if (result.IsTimedOut()) {
- timed_out = true;
- // Even though we timed out, we will still make one more attempt to
- // acquire lock below (it is possible the lock expired and we
- // were never signaled).
- }
-
- if (result.ok() || result.IsTimedOut()) {
- result = AcquireLocked(lock_map, stripe, key, env, std::move(lock_info),
- &expire_time_hint, &wait_ids);
- }
- } while (!result.ok() && !timed_out);
- }
-
- stripe->stripe_mutex->UnLock();
-
- return result;
-}
-
-void TransactionLockMgr::DecrementWaiters(
- const PessimisticTransaction* txn,
- const autovector<TransactionID>& wait_ids) {
- std::lock_guard<std::mutex> lock(wait_txn_map_mutex_);
- DecrementWaitersImpl(txn, wait_ids);
-}
-
-void TransactionLockMgr::DecrementWaitersImpl(
- const PessimisticTransaction* txn,
- const autovector<TransactionID>& wait_ids) {
- auto id = txn->GetID();
- assert(wait_txn_map_.Contains(id));
- wait_txn_map_.Delete(id);
-
- for (auto wait_id : wait_ids) {
- rev_wait_txn_map_.Get(wait_id)--;
- if (rev_wait_txn_map_.Get(wait_id) == 0) {
- rev_wait_txn_map_.Delete(wait_id);
- }
- }
-}
-
-bool TransactionLockMgr::IncrementWaiters(
- const PessimisticTransaction* txn,
- const autovector<TransactionID>& wait_ids, const std::string& key,
- const uint32_t& cf_id, const bool& exclusive, Env* const env) {
- auto id = txn->GetID();
- std::vector<int> queue_parents(static_cast<size_t>(txn->GetDeadlockDetectDepth()));
- std::vector<TransactionID> queue_values(static_cast<size_t>(txn->GetDeadlockDetectDepth()));
- std::lock_guard<std::mutex> lock(wait_txn_map_mutex_);
- assert(!wait_txn_map_.Contains(id));
-
- wait_txn_map_.Insert(id, {wait_ids, cf_id, exclusive, key});
-
- for (auto wait_id : wait_ids) {
- if (rev_wait_txn_map_.Contains(wait_id)) {
- rev_wait_txn_map_.Get(wait_id)++;
- } else {
- rev_wait_txn_map_.Insert(wait_id, 1);
- }
- }
-
- // No deadlock if nobody is waiting on self.
- if (!rev_wait_txn_map_.Contains(id)) {
- return false;
- }
-
- const auto* next_ids = &wait_ids;
- int parent = -1;
- int64_t deadlock_time = 0;
- for (int tail = 0, head = 0; head < txn->GetDeadlockDetectDepth(); head++) {
- int i = 0;
- if (next_ids) {
- for (; i < static_cast<int>(next_ids->size()) &&
- tail + i < txn->GetDeadlockDetectDepth();
- i++) {
- queue_values[tail + i] = (*next_ids)[i];
- queue_parents[tail + i] = parent;
- }
- tail += i;
- }
-
- // No more items in the list, meaning no deadlock.
- if (tail == head) {
- return false;
- }
-
- auto next = queue_values[head];
- if (next == id) {
- std::vector<DeadlockInfo> path;
- while (head != -1) {
- assert(wait_txn_map_.Contains(queue_values[head]));
-
- auto extracted_info = wait_txn_map_.Get(queue_values[head]);
- path.push_back({queue_values[head], extracted_info.m_cf_id,
- extracted_info.m_exclusive,
- extracted_info.m_waiting_key});
- head = queue_parents[head];
- }
- env->GetCurrentTime(&deadlock_time);
- std::reverse(path.begin(), path.end());
- dlock_buffer_.AddNewPath(DeadlockPath(path, deadlock_time));
- deadlock_time = 0;
- DecrementWaitersImpl(txn, wait_ids);
- return true;
- } else if (!wait_txn_map_.Contains(next)) {
- next_ids = nullptr;
- continue;
- } else {
- parent = head;
- next_ids = &(wait_txn_map_.Get(next).m_neighbors);
- }
- }
-
- // Wait cycle too big, just assume deadlock.
- env->GetCurrentTime(&deadlock_time);
- dlock_buffer_.AddNewPath(DeadlockPath(deadlock_time, true));
- DecrementWaitersImpl(txn, wait_ids);
- return true;
-}
-
-// Try to lock this key after we have acquired the mutex.
-// Sets *expire_time to the expiration time in microseconds
-// or 0 if no expiration.
-// REQUIRED: Stripe mutex must be held.
-Status TransactionLockMgr::AcquireLocked(LockMap* lock_map,
- LockMapStripe* stripe,
- const std::string& key, Env* env,
- LockInfo&& txn_lock_info,
- uint64_t* expire_time,
- autovector<TransactionID>* txn_ids) {
- assert(txn_lock_info.txn_ids.size() == 1);
-
- Status result;
- // Check if this key is already locked
- auto stripe_iter = stripe->keys.find(key);
- if (stripe_iter != stripe->keys.end()) {
- // Lock already held
- LockInfo& lock_info = stripe_iter->second;
- assert(lock_info.txn_ids.size() == 1 || !lock_info.exclusive);
-
- if (lock_info.exclusive || txn_lock_info.exclusive) {
- if (lock_info.txn_ids.size() == 1 &&
- lock_info.txn_ids[0] == txn_lock_info.txn_ids[0]) {
- // The list contains one txn and we're it, so just take it.
- lock_info.exclusive = txn_lock_info.exclusive;
- lock_info.expiration_time = txn_lock_info.expiration_time;
- } else {
- // Check if it's expired. Skips over txn_lock_info.txn_ids[0] in case
- // it's there for a shared lock with multiple holders which was not
- // caught in the first case.
- if (IsLockExpired(txn_lock_info.txn_ids[0], lock_info, env,
- expire_time)) {
- // lock is expired, can steal it
- lock_info.txn_ids = txn_lock_info.txn_ids;
- lock_info.exclusive = txn_lock_info.exclusive;
- lock_info.expiration_time = txn_lock_info.expiration_time;
- // lock_cnt does not change
- } else {
- result = Status::TimedOut(Status::SubCode::kLockTimeout);
- *txn_ids = lock_info.txn_ids;
- }
- }
- } else {
- // We are requesting shared access to a shared lock, so just grant it.
- lock_info.txn_ids.push_back(txn_lock_info.txn_ids[0]);
- // Using std::max means that expiration time never goes down even when
- // a transaction is removed from the list. The correct solution would be
- // to track expiry for every transaction, but this would also work for
- // now.
- lock_info.expiration_time =
- std::max(lock_info.expiration_time, txn_lock_info.expiration_time);
- }
- } else { // Lock not held.
- // Check lock limit
- if (max_num_locks_ > 0 &&
- lock_map->lock_cnt.load(std::memory_order_acquire) >= max_num_locks_) {
- result = Status::Busy(Status::SubCode::kLockLimit);
- } else {
- // acquire lock
- stripe->keys.emplace(key, std::move(txn_lock_info));
-
- // Maintain lock count if there is a limit on the number of locks
- if (max_num_locks_) {
- lock_map->lock_cnt++;
- }
- }
- }
-
- return result;
-}
-
-void TransactionLockMgr::UnLockKey(const PessimisticTransaction* txn,
- const std::string& key,
- LockMapStripe* stripe, LockMap* lock_map,
- Env* env) {
-#ifdef NDEBUG
- (void)env;
-#endif
- TransactionID txn_id = txn->GetID();
-
- auto stripe_iter = stripe->keys.find(key);
- if (stripe_iter != stripe->keys.end()) {
- auto& txns = stripe_iter->second.txn_ids;
- auto txn_it = std::find(txns.begin(), txns.end(), txn_id);
- // Found the key we locked. unlock it.
- if (txn_it != txns.end()) {
- if (txns.size() == 1) {
- stripe->keys.erase(stripe_iter);
- } else {
- auto last_it = txns.end() - 1;
- if (txn_it != last_it) {
- *txn_it = *last_it;
- }
- txns.pop_back();
- }
-
- if (max_num_locks_ > 0) {
- // Maintain lock count if there is a limit on the number of locks.
- assert(lock_map->lock_cnt.load(std::memory_order_relaxed) > 0);
- lock_map->lock_cnt--;
- }
- }
- } else {
- // This key is either not locked or locked by someone else. This should
- // only happen if the unlocking transaction has expired.
- assert(txn->GetExpirationTime() > 0 &&
- txn->GetExpirationTime() < env->NowMicros());
- }
-}
-
-void TransactionLockMgr::UnLock(PessimisticTransaction* txn,
- uint32_t column_family_id,
- const std::string& key, Env* env) {
- std::shared_ptr<LockMap> lock_map_ptr = GetLockMap(column_family_id);
- LockMap* lock_map = lock_map_ptr.get();
- if (lock_map == nullptr) {
- // Column Family must have been dropped.
- return;
- }
-
- // Lock the mutex for the stripe that this key hashes to
- size_t stripe_num = lock_map->GetStripe(key);
- assert(lock_map->lock_map_stripes_.size() > stripe_num);
- LockMapStripe* stripe = lock_map->lock_map_stripes_.at(stripe_num);
-
- stripe->stripe_mutex->Lock();
- UnLockKey(txn, key, stripe, lock_map, env);
- stripe->stripe_mutex->UnLock();
-
- // Signal waiting threads to retry locking
- stripe->stripe_cv->NotifyAll();
-}
-
-void TransactionLockMgr::UnLock(const PessimisticTransaction* txn,
- const TransactionKeyMap* key_map, Env* env) {
- for (auto& key_map_iter : *key_map) {
- uint32_t column_family_id = key_map_iter.first;
- auto& keys = key_map_iter.second;
-
- std::shared_ptr<LockMap> lock_map_ptr = GetLockMap(column_family_id);
- LockMap* lock_map = lock_map_ptr.get();
-
- if (lock_map == nullptr) {
- // Column Family must have been dropped.
- return;
- }
-
- // Bucket keys by lock_map_ stripe
- std::unordered_map<size_t, std::vector<const std::string*>> keys_by_stripe(
- std::max(keys.size(), lock_map->num_stripes_));
-
- for (auto& key_iter : keys) {
- const std::string& key = key_iter.first;
-
- size_t stripe_num = lock_map->GetStripe(key);
- keys_by_stripe[stripe_num].push_back(&key);
- }
-
- // For each stripe, grab the stripe mutex and unlock all keys in this stripe
- for (auto& stripe_iter : keys_by_stripe) {
- size_t stripe_num = stripe_iter.first;
- auto& stripe_keys = stripe_iter.second;
-
- assert(lock_map->lock_map_stripes_.size() > stripe_num);
- LockMapStripe* stripe = lock_map->lock_map_stripes_.at(stripe_num);
-
- stripe->stripe_mutex->Lock();
-
- for (const std::string* key : stripe_keys) {
- UnLockKey(txn, *key, stripe, lock_map, env);
- }
-
- stripe->stripe_mutex->UnLock();
-
- // Signal waiting threads to retry locking
- stripe->stripe_cv->NotifyAll();
- }
- }
-}
-
-TransactionLockMgr::LockStatusData TransactionLockMgr::GetLockStatusData() {
- LockStatusData data;
- // Lock order here is important. The correct order is lock_map_mutex_, then
- // for every column family ID in ascending order lock every stripe in
- // ascending order.
- InstrumentedMutexLock l(&lock_map_mutex_);
-
- std::vector<uint32_t> cf_ids;
- for (const auto& map : lock_maps_) {
- cf_ids.push_back(map.first);
- }
- std::sort(cf_ids.begin(), cf_ids.end());
-
- for (auto i : cf_ids) {
- const auto& stripes = lock_maps_[i]->lock_map_stripes_;
- // Iterate and lock all stripes in ascending order.
- for (const auto& j : stripes) {
- j->stripe_mutex->Lock();
- for (const auto& it : j->keys) {
- struct KeyLockInfo info;
- info.exclusive = it.second.exclusive;
- info.key = it.first;
- for (const auto& id : it.second.txn_ids) {
- info.ids.push_back(id);
- }
- data.insert({i, info});
- }
- }
- }
-
- // Unlock everything. Unlocking order is not important.
- for (auto i : cf_ids) {
- const auto& stripes = lock_maps_[i]->lock_map_stripes_;
- for (const auto& j : stripes) {
- j->stripe_mutex->UnLock();
- }
- }
-
- return data;
-}
-std::vector<DeadlockPath> TransactionLockMgr::GetDeadlockInfoBuffer() {
- return dlock_buffer_.PrepareBuffer();
-}
-
-void TransactionLockMgr::Resize(uint32_t target_size) {
- dlock_buffer_.Resize(target_size);
-}
-
-} // namespace ROCKSDB_NAMESPACE
-#endif // ROCKSDB_LITE
projects / ceph.git / blobdiff