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
17 #include "perfetto/ext/base/clock_snapshots.h"
18
19 #include "perfetto/base/build_config.h"
20 #include "perfetto/base/time.h"
21 #include "protos/perfetto/common/builtin_clock.pbzero.h"
22
23 namespace perfetto::base {
24
CaptureClockSnapshots()25 ClockSnapshotVector CaptureClockSnapshots() {
26 ClockSnapshotVector snapshot_data;
27 #if !PERFETTO_BUILDFLAG(PERFETTO_OS_APPLE) && \
28 !PERFETTO_BUILDFLAG(PERFETTO_OS_WIN) && \
29 !PERFETTO_BUILDFLAG(PERFETTO_OS_NACL)
30 struct {
31 clockid_t id;
32 protos::pbzero::BuiltinClock type;
33 struct timespec ts;
34 } clocks[] = {
35 {CLOCK_BOOTTIME, protos::pbzero::BUILTIN_CLOCK_BOOTTIME, {0, 0}},
36 {CLOCK_REALTIME_COARSE,
37 protos::pbzero::BUILTIN_CLOCK_REALTIME_COARSE,
38 {0, 0}},
39 {CLOCK_MONOTONIC_COARSE,
40 protos::pbzero::BUILTIN_CLOCK_MONOTONIC_COARSE,
41 {0, 0}},
42 {CLOCK_REALTIME, protos::pbzero::BUILTIN_CLOCK_REALTIME, {0, 0}},
43 {CLOCK_MONOTONIC, protos::pbzero::BUILTIN_CLOCK_MONOTONIC, {0, 0}},
44 {CLOCK_MONOTONIC_RAW,
45 protos::pbzero::BUILTIN_CLOCK_MONOTONIC_RAW,
46 {0, 0}},
47 };
48 // First snapshot all the clocks as atomically as we can.
49 for (auto& clock : clocks) {
50 if (clock_gettime(clock.id, &clock.ts) == -1)
51 PERFETTO_DLOG("clock_gettime failed for clock %d", clock.id);
52 }
53 for (auto& clock : clocks) {
54 snapshot_data.push_back(ClockReading(
55 static_cast<uint32_t>(clock.type),
56 static_cast<uint64_t>(base::FromPosixTimespec(clock.ts).count())));
57 }
58 #else // OS_APPLE || OS_WIN && OS_NACL
59 auto wall_time_ns = static_cast<uint64_t>(base::GetWallTimeNs().count());
60 // The default trace clock is boot time, so we always need to emit a path to
61 // it. However since we don't actually have a boot time source on these
62 // platforms, pretend that wall time equals boot time.
63 snapshot_data.push_back(
64 ClockReading(protos::pbzero::BUILTIN_CLOCK_BOOTTIME, wall_time_ns));
65 snapshot_data.push_back(
66 ClockReading(protos::pbzero::BUILTIN_CLOCK_MONOTONIC, wall_time_ns));
67 #endif
68
69 #if PERFETTO_BUILDFLAG(PERFETTO_ARCH_CPU_X86_64)
70 // X86-specific but OS-independent TSC clocksource
71 snapshot_data.push_back(
72 ClockReading(protos::pbzero::BUILTIN_CLOCK_TSC, base::Rdtsc()));
73 #endif // PERFETTO_BUILDFLAG(PERFETTO_ARCH_CPU_X86_64)
74
75 return snapshot_data;
76 }
77
78 } // namespace perfetto
79