xref: /aosp_15_r20/external/perfetto/protos/perfetto/ipc/relay_port.proto (revision 6dbdd20afdafa5e3ca9b8809fa73465d530080dc) 
1/*
2 * Copyright (C) 2024 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17syntax = "proto2";
18
19package perfetto.protos;
20
21// IPC interface definition for serving the requests from the relay service.
22service RelayPort {
23  // Synchronize the clocks with a guest. This is used for multi-machine tracing
24  // with a VM guest or a remote machine. The client may make consecutive calls
25  // of this method to get better results.
26  rpc SyncClock(SyncClockRequest) returns (SyncClockResponse) {}
27}
28
29// For the client to send its clock readings to the host.
30message SyncClockRequest {
31  // Relay service synchronizes its clocks with the host using round-trip
32  // messages of clock snapshots on both sides for an estimation of clock
33  // offsets of the built-in clocks.
34  enum Phase {
35    // Clock synchronization starts with the client (relay service) sends its
36    // clock snapshots in the PING phase. The host also snapshots its clocks on
37    // receiving the request and acks the client.
38    PING = 1;
39    // Clock synchronization completes with the client sending the second clock
40    // snapshot request after the round-trip of the PING request. The host
41    // estimates the clock offsets using 2 consecutive clock snapshots on both
42    // sides.
43    UPDATE = 2;
44  };
45
46  message Clock {
47    // The clock ID enumerated in builtin_clocks.proto.
48    optional uint32 clock_id = 1;
49    // The clock reading value (e.g. in nanoseconds for BUILTIN_CLOCK_BOOTTIME).
50    optional uint64 timestamp = 2;
51  }
52
53  optional Phase phase = 1;
54  repeated Clock clocks = 2;
55}
56
57// The host doesn't send any information back to the client.
58message SyncClockResponse {}
59