1 files changed, 0 insertions, 131 deletions
diff --git a/third_party/abseil-cpp/absl/strings/internal/cordz_handle.h b/third_party/abseil-cpp/absl/strings/internal/cordz_handle.h
deleted file mode 100644
index 5df53c782a..0000000000
--- a/third_party/abseil-cpp/absl/strings/internal/cordz_handle.h
+++ /dev/null
@@ -1,131 +0,0 @@
-// Copyright 2019 The Abseil Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      https://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef ABSL_STRINGS_CORDZ_HANDLE_H_
-#define ABSL_STRINGS_CORDZ_HANDLE_H_
-
-#include <atomic>
-#include <vector>
-
-#include "absl/base/config.h"
-#include "absl/base/internal/raw_logging.h"
-#include "absl/base/internal/spinlock.h"
-#include "absl/synchronization/mutex.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-namespace cord_internal {
-
-// This base class allows multiple types of object (CordzInfo and
-// CordzSampleToken) to exist simultaneously on the delete queue (pointed to by
-// global_dq_tail and traversed using dq_prev_ and dq_next_). The
-// delete queue guarantees that once a profiler creates a CordzSampleToken and
-// has gained visibility into a CordzInfo object, that CordzInfo object will not
-// be deleted prematurely. This allows the profiler to inspect all CordzInfo
-// objects that are alive without needing to hold a global lock.
-class CordzHandle {
- public:
-  CordzHandle() : CordzHandle(false) {}
-
-  bool is_snapshot() const { return is_snapshot_; }
-
-  // Returns true if this instance is safe to be deleted because it is either a
-  // snapshot, which is always safe to delete, or not included in the global
-  // delete queue and thus not included in any snapshot.
-  // Callers are responsible for making sure this instance can not be newly
-  // discovered by other threads. For example, CordzInfo instances first de-list
-  // themselves from the global CordzInfo list before determining if they are
-  // safe to be deleted directly.
-  // If SafeToDelete returns false, callers MUST use the Delete() method to
-  // safely queue CordzHandle instances for deletion.
-  bool SafeToDelete() const;
-
-  // Deletes the provided instance, or puts it on the delete queue to be deleted
-  // once there are no more sample tokens (snapshot) instances potentially
-  // referencing the instance. `handle` should not be null.
-  static void Delete(CordzHandle* handle);
-
-  // Returns the current entries in the delete queue in LIFO order.
-  static std::vector<const CordzHandle*> DiagnosticsGetDeleteQueue();
-
-  // Returns true if the provided handle is nullptr or guarded by this handle.
-  // Since the CordzSnapshot token is itself a CordzHandle, this method will
-  // allow tests to check if that token is keeping an arbitrary CordzHandle
-  // alive.
-  bool DiagnosticsHandleIsSafeToInspect(const CordzHandle* handle) const;
-
-  // Returns the current entries in the delete queue, in LIFO order, that are
-  // protected by this. CordzHandle objects are only placed on the delete queue
-  // after CordzHandle::Delete is called with them as an argument. Only
-  // CordzHandle objects that are not also CordzSnapshot objects will be
-  // included in the return vector. For each of the handles in the return
-  // vector, the earliest that their memory can be freed is when this
-  // CordzSnapshot object is deleted.
-  std::vector<const CordzHandle*> DiagnosticsGetSafeToInspectDeletedHandles();
-
- protected:
-  explicit CordzHandle(bool is_snapshot);
-  virtual ~CordzHandle();
-
- private:
-  // Global queue data. CordzHandle stores a pointer to the global queue
-  // instance to harden against ODR violations.
-  struct Queue {
-    constexpr explicit Queue(absl::ConstInitType)
-        : mutex(absl::kConstInit,
-                absl::base_internal::SCHEDULE_COOPERATIVE_AND_KERNEL) {}
-
-    absl::base_internal::SpinLock mutex;
-    std::atomic<CordzHandle*> dq_tail ABSL_GUARDED_BY(mutex){nullptr};
-
-    // Returns true if this delete queue is empty. This method does not acquire
-    // the lock, but does a 'load acquire' observation on the delete queue tail.
-    // It is used inside Delete() to check for the presence of a delete queue
-    // without holding the lock. The assumption is that the caller is in the
-    // state of 'being deleted', and can not be newly discovered by a concurrent
-    // 'being constructed' snapshot instance. Practically, this means that any
-    // such discovery (`find`, 'first' or 'next', etc) must have proper 'happens
-    // before / after' semantics and atomic fences.
-    bool IsEmpty() const ABSL_NO_THREAD_SAFETY_ANALYSIS {
-      return dq_tail.load(std::memory_order_acquire) == nullptr;
-    }
-  };
-
-  void ODRCheck() const {
-#ifndef NDEBUG
-    ABSL_RAW_CHECK(queue_ == &global_queue_, "ODR violation in Cord");
-#endif
-  }
-
-  ABSL_CONST_INIT static Queue global_queue_;
-  Queue* const queue_ = &global_queue_;
-  const bool is_snapshot_;
-
-  // dq_prev_ and dq_next_ require the global queue mutex to be held.
-  // Unfortunately we can't use thread annotations such that the thread safety
-  // analysis understands that queue_ and global_queue_ are one and the same.
-  CordzHandle* dq_prev_  = nullptr;
-  CordzHandle* dq_next_ = nullptr;
-};
-
-class CordzSnapshot : public CordzHandle {
- public:
-  CordzSnapshot() : CordzHandle(true) {}
-};
-
-}  // namespace cord_internal
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_STRINGS_CORDZ_HANDLE_H_