Fathom TCP level changes. TracedBuffer for keeping track of all buffers

to be traced. Adding tests for Fathom and TracedBuffer. A lot more.
Please read PR description.

1 files changed, 81 insertions, 0 deletions

diff --git a/src/core/lib/iomgr/buffer_list.h b/src/core/lib/iomgr/buffer_list.h
new file mode 100644
index 0000000000..d42f97ff97
--- /dev/null
+++ b/src/core/lib/iomgr/buffer_list.h
@@ -0,0 +1,81 @@
+/*
+ *
+ * Copyright 2018 gRPC 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
+ *
+ *     http://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 GRPC_CORE_LIB_IOMGR_BUFFER_LIST_H
+#define GRPC_CORE_LIB_IOMGR_BUFFER_LIST_H
+
+#include <grpc/support/port_platform.h>
+
+#include "src/core/lib/iomgr/port.h"
+
+#include <grpc/support/time.h>
+
+#include "src/core/lib/gprpp/memory.h"
+#include "src/core/lib/iomgr/error.h"
+#include "src/core/lib/iomgr/internal_errqueue.h"
+
+namespace grpc_core {
+struct Timestamps {
+  gpr_timespec sendmsg_time;
+  gpr_timespec scheduled_time;
+  gpr_timespec sent_time;
+  gpr_timespec acked_time;
+};
+
+#ifdef GRPC_LINUX_ERRQUEUE
+class TracedBuffer {
+ public:
+  /** Add a new entry in the TracedBuffer list pointed to by head */
+  static void AddNewEntry(grpc_core::TracedBuffer** head, uint32_t seq_no,
+                          void* arg);
+
+  /** Processes a timestamp received */
+  static void ProcessTimestamp(grpc_core::TracedBuffer** head,
+                               struct sock_extended_err* serr,
+                               struct scm_timestamping* tss);
+
+  /** Calls the callback for each traced buffer in the list with timestamps that
+   * it has. */
+  static void Shutdown(grpc_core::TracedBuffer** head,
+                       grpc_error* shutdown_err);
+
+ private:
+  GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_NEW
+
+  TracedBuffer(int seq_no, void* arg)
+      : seq_no_(seq_no), arg_(arg), next_(nullptr) {
+    gpr_log(GPR_INFO, "seq_no %d", seq_no_);
+  }
+
+  uint32_t seq_no_; /* The sequence number for the last byte in the buffer */
+  void* arg_;       /* The arg to pass to timestamps_callback */
+  grpc_core::Timestamps ts_;
+  grpc_core::TracedBuffer* next_;
+};
+#else  /* GRPC_LINUX_ERRQUEUE */
+class TracedBuffer {};
+#endif /* GRPC_LINUX_ERRQUEUE */
+
+/** Sets the timestamp callback */
+void grpc_tcp_set_write_timestamps_callback(void (*fn)(void*,
+                                                       grpc_core::Timestamps*,
+                                                       grpc_error* error));
+
+};  // namespace grpc_core
+
+#endif /* GRPC_CORE_LIB_IOMGR_BUFFER_LIST_H */