Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 131 insertions, 0 deletions

diff --git a/src/rocksdb/monitoring/thread_status_util.h b/src/rocksdb/monitoring/thread_status_util.h
new file mode 100644
index 000000000..0137d2682
--- /dev/null
+++ b/src/rocksdb/monitoring/thread_status_util.h
@@ -0,0 +1,131 @@
+// 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).
+
+#pragma once
+
+#include <string>
+
+#include "monitoring/thread_status_updater.h"
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/thread_status.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+class ColumnFamilyData;
+
+// The static utility class for updating thread-local status.
+//
+// The thread-local status is updated via the thread-local cached
+// pointer thread_updater_local_cache_.  During each function call,
+// when ThreadStatusUtil finds thread_updater_local_cache_ is
+// left uninitialized (determined by thread_updater_initialized_),
+// it will tries to initialize it using the return value of
+// Env::GetThreadStatusUpdater().  When thread_updater_local_cache_
+// is initialized by a non-null pointer, each function call will
+// then update the status of the current thread.  Otherwise,
+// all function calls to ThreadStatusUtil will be no-op.
+class ThreadStatusUtil {
+ public:
+  // Register the current thread for tracking.
+  static void RegisterThread(const Env* env,
+                             ThreadStatus::ThreadType thread_type);
+
+  // Unregister the current thread.
+  static void UnregisterThread();
+
+  // Create an entry in the global ColumnFamilyInfo table for the
+  // specified column family.  This function should be called only
+  // when the current thread does not hold db_mutex.
+  static void NewColumnFamilyInfo(const DB* db, const ColumnFamilyData* cfd,
+                                  const std::string& cf_name, const Env* env);
+
+  // Erase the ConstantColumnFamilyInfo that is associated with the
+  // specified ColumnFamilyData.  This function should be called only
+  // when the current thread does not hold db_mutex.
+  static void EraseColumnFamilyInfo(const ColumnFamilyData* cfd);
+
+  // Erase all ConstantColumnFamilyInfo that is associated with the
+  // specified db instance.  This function should be called only when
+  // the current thread does not hold db_mutex.
+  static void EraseDatabaseInfo(const DB* db);
+
+  // Update the thread status to indicate the current thread is doing
+  // something related to the specified column family.
+  static void SetColumnFamily(const ColumnFamilyData* cfd, const Env* env,
+                              bool enable_thread_tracking);
+
+  static void SetThreadOperation(ThreadStatus::OperationType type);
+
+  static ThreadStatus::OperationStage SetThreadOperationStage(
+      ThreadStatus::OperationStage stage);
+
+  static void SetThreadOperationProperty(int code, uint64_t value);
+
+  static void IncreaseThreadOperationProperty(int code, uint64_t delta);
+
+  static void SetThreadState(ThreadStatus::StateType type);
+
+  static void ResetThreadStatus();
+
+#ifndef NDEBUG
+  static void TEST_SetStateDelay(const ThreadStatus::StateType state,
+                                 int micro);
+  static void TEST_StateDelay(const ThreadStatus::StateType state);
+#endif
+
+ protected:
+  // Initialize the thread-local ThreadStatusUpdater when it finds
+  // the cached value is nullptr.  Returns true if it has cached
+  // a non-null pointer.
+  static bool MaybeInitThreadLocalUpdater(const Env* env);
+
+#ifdef ROCKSDB_USING_THREAD_STATUS
+  // A boolean flag indicating whether thread_updater_local_cache_
+  // is initialized.  It is set to true when an Env uses any
+  // ThreadStatusUtil functions using the current thread other
+  // than UnregisterThread().  It will be set to false when
+  // UnregisterThread() is called.
+  //
+  // When this variable is set to true, thread_updater_local_cache_
+  // will not be updated until this variable is again set to false
+  // in UnregisterThread().
+  static thread_local bool thread_updater_initialized_;
+
+  // The thread-local cached ThreadStatusUpdater that caches the
+  // thread_status_updater_ of the first Env that uses any ThreadStatusUtil
+  // function other than UnregisterThread().  This variable will
+  // be cleared when UnregisterThread() is called.
+  //
+  // When this variable is set to a non-null pointer, then the status
+  // of the current thread will be updated when a function of
+  // ThreadStatusUtil is called.  Otherwise, all functions of
+  // ThreadStatusUtil will be no-op.
+  //
+  // When thread_updater_initialized_ is set to true, this variable
+  // will not be updated until this thread_updater_initialized_ is
+  // again set to false in UnregisterThread().
+  static thread_local ThreadStatusUpdater* thread_updater_local_cache_;
+#else
+  static bool thread_updater_initialized_;
+  static ThreadStatusUpdater* thread_updater_local_cache_;
+#endif
+};
+
+// A helper class for updating thread state.  It will set the
+// thread state according to the input parameter in its constructor
+// and set the thread state to the previous state in its destructor.
+class AutoThreadOperationStageUpdater {
+ public:
+  explicit AutoThreadOperationStageUpdater(ThreadStatus::OperationStage stage);
+  ~AutoThreadOperationStageUpdater();
+
+#ifdef ROCKSDB_USING_THREAD_STATUS
+ private:
+  ThreadStatus::OperationStage prev_stage_;
+#endif
+};
+
+}  // namespace ROCKSDB_NAMESPACE