1 /*
2 * Copyright 2019 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 #pragma once
18
19 #include <chrono>
20 #include <cmath>
21 #include <functional>
22 #include <string>
23
24 #include <cutils/compiler.h>
25 #include <utils/Trace.h>
26
27 namespace std {
28 template <class Rep, class Period>
signbit(std::chrono::duration<Rep,Period> v)29 bool signbit(std::chrono::duration<Rep, Period> v) {
30 return signbit(std::chrono::duration_cast<std::chrono::nanoseconds>(v).count());
31 }
32 } // namespace std
33
34 namespace android {
35
36 namespace {
37 template <typename T>
to_int64(T v)38 int64_t to_int64(T v) {
39 return int64_t(v);
40 }
41
42 template <class Rep, class Period>
to_int64(std::chrono::duration<Rep,Period> v)43 int64_t to_int64(std::chrono::duration<Rep, Period> v) {
44 return int64_t(v.count());
45 }
46 } // namespace
47
48 template <typename T>
49 class TracedOrdinal {
50 public:
51 static_assert(std::is_same<bool, T>() || (std::is_signed<T>() && std::is_integral<T>()) ||
52 std::is_same<std::chrono::nanoseconds, T>(),
53 "Type is not supported. Please test it with systrace before adding "
54 "it to the list.");
55
TracedOrdinal(std::string name,T initialValue)56 TracedOrdinal(std::string name, T initialValue)
57 : mName(std::move(name)),
58 mHasGoneNegative(std::signbit(initialValue)),
59 mData(initialValue) {
60 trace();
61 }
62
get()63 T get() const { return mData; }
64
T()65 operator T() const { return get(); }
66
67 TracedOrdinal& operator=(T other) {
68 mData = other;
69 mHasGoneNegative = mHasGoneNegative || std::signbit(mData);
70 trace();
71 return *this;
72 }
73
74 private:
trace()75 void trace() {
76 if (CC_LIKELY(!ATRACE_ENABLED())) {
77 return;
78 }
79
80 if (mNameNegative.empty()) {
81 mNameNegative = mName + "Negative";
82 }
83
84 if (!std::signbit(mData)) {
85 ATRACE_INT64(mName.c_str(), to_int64(mData));
86 if (mHasGoneNegative) {
87 ATRACE_INT64(mNameNegative.c_str(), 0);
88 }
89 } else {
90 ATRACE_INT64(mNameNegative.c_str(), -to_int64(mData));
91 ATRACE_INT64(mName.c_str(), 0);
92 }
93 }
94
95 const std::string mName;
96 std::string mNameNegative;
97 bool mHasGoneNegative;
98 T mData;
99 };
100
101 } // namespace android
102