protos/perfetto/common/data_source_descriptor.proto

/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * 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.
 */

syntax = "proto2";

package perfetto.protos;

import "protos/perfetto/common/ftrace_descriptor.proto";
import "protos/perfetto/common/gpu_counter_descriptor.proto";
import "protos/perfetto/common/track_event_descriptor.proto";

// This message is sent from Producer(s) to the tracing Service when registering
// to advertise their capabilities. It describes the structure of tracing
// protos that will be produced by the data source and the supported filters.
message DataSourceDescriptor {
  // e.g., "linux.ftrace", "chromium.tracing"
  optional string name = 1;

  // When non-zero, this is a unique ID within the scope of the Producer for
  // this data source (it is NOT globally unique). This is useful to
  // differentiate between data sources with matching names when calling
  // UpdateDataSource(). This field has been introduced in November 2021
  // (v22, Android T) and is not supported on older versions.
  optional uint64 id = 7;

  // When true the data source is expected to ack the stop request through the
  // NotifyDataSourceStopped() IPC. This field has been introduced after
  // Android P in Jul 2018 and is not supported on older versions.
  optional bool will_notify_on_stop = 2;

  // When true the data source is expected to ack the start request through the
  // NotifyDataSourceStarted() IPC. This field has been introduced after
  // Android P in March 2019 and is not supported on older versions.
  optional bool will_notify_on_start = 3;

  // If true, opt into receiving the ClearIncrementalState() IPC. This should be
  // set if the data source writes packets that refer to previous trace
  // contents, and knows how to stop referring to the already-emitted data.
  optional bool handles_incremental_state_clear = 4;

  // If true, indicates that the data source does nothing upon Flush. This
  // allows the service to reduce the flush-related IPC traffic and better deal
  // with frozen producers (see go/perfetto-frozen). This is usually the case
  // for data sources like 'track_event' that don't have access to the various
  // thread task runners to post a flush task and rely purely on server-side
  // scraping.
  // Introduced in v39 / Android V.
  optional bool no_flush = 9;

  // Optional specification about available GPU counters.
  optional GpuCounterDescriptor gpu_counter_descriptor = 5 [lazy = true];

  optional TrackEventDescriptor track_event_descriptor = 6 [lazy = true];

  optional FtraceDescriptor ftrace_descriptor = 8 [lazy = true];
}