xref: /aosp_15_r20/external/perfetto/src/trace_processor/importers/perf/perf_event_attr.h (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 
17 #ifndef SRC_TRACE_PROCESSOR_IMPORTERS_PERF_PERF_EVENT_ATTR_H_
18 #define SRC_TRACE_PROCESSOR_IMPORTERS_PERF_PERF_EVENT_ATTR_H_
19 
20 #include <sys/types.h>
21 #include <cstddef>
22 #include <cstdint>
23 #include <optional>
24 #include <string>
25 #include <unordered_map>
26 #include <utility>
27 
28 #include "perfetto/trace_processor/ref_counted.h"
29 #include "src/trace_processor/importers/common/clock_tracker.h"
30 #include "src/trace_processor/importers/perf/perf_counter.h"
31 #include "src/trace_processor/importers/perf/perf_event.h"
32 #include "src/trace_processor/tables/profiler_tables_py.h"
33 
34 namespace perfetto::trace_processor {
35 
36 class TraceProcessorContext;
37 
38 namespace perf_importer {
39 
40 // Wrapper around a `perf_event_attr` object that add some helper methods.
41 class PerfEventAttr : public RefCounted {
42  public:
43   PerfEventAttr(TraceProcessorContext* context,
44                 tables::PerfSessionTable::Id perf_session_id_,
45                 perf_event_attr attr);
46   ~PerfEventAttr();
type()47   uint32_t type() const { return attr_.type; }
config()48   uint64_t config() const { return attr_.config; }
sample_type()49   uint64_t sample_type() const { return attr_.sample_type; }
read_format()50   uint64_t read_format() const { return attr_.read_format; }
sample_id_all()51   bool sample_id_all() const { return !!attr_.sample_id_all; }
52 
53   // Returns period if set.
sample_period()54   std::optional<uint64_t> sample_period() const {
55     // attr_.freq tells whether attr_.sample_period or attr_.sample_freq is set.
56     return attr_.freq ? std::nullopt : std::make_optional(attr_.sample_period);
57   }
58 
59   // Returns frequency if set.
sample_freq()60   std::optional<uint64_t> sample_freq() const {
61     // attr_.freq tells whether attr_.sample_period or attr_.sample_freq is set.
62     return attr_.freq ? std::make_optional(attr_.sample_freq) : std::nullopt;
63   }
64 
65   // Offset from the end of a record's payload to the time filed (if present).
66   // To be used with non `PERF_RECORD_SAMPLE` records
time_offset_from_end()67   std::optional<size_t> time_offset_from_end() const {
68     return time_offset_from_end_;
69   }
70 
71   // Offset from the start of a record's payload to the time filed (if present).
72   // To be used with `PERF_RECORD SAMPLE` records
time_offset_from_start()73   std::optional<size_t> time_offset_from_start() const {
74     return time_offset_from_start_;
75   }
76 
77   // Offsets from start and end of record payload to the id field. These offsets
78   // are used to determine the event_id and thus the perf_event_attr value of a
79   // record. During tokenization we need to determine the `sample_type` to be
80   // able to later parse the record. The `sample_type` is stored in the
81   // `perf_event_attr` structure.
82 
83   // To be used with PERF_SAMPLE_RECORD records
id_offset_from_start()84   std::optional<size_t> id_offset_from_start() const {
85     return id_offset_from_start_;
86   }
87   // To be used with non PERF_SAMPLE_RECORD records if `sample_id_all` is set.
id_offset_from_end()88   std::optional<size_t> id_offset_from_end() const {
89     return id_offset_from_end_;
90   }
91 
set_event_name(std::string event_name)92   void set_event_name(std::string event_name) {
93     event_name_ = std::move(event_name);
94   }
95 
sample_id_size()96   size_t sample_id_size() const { return sample_id_size_; }
97 
98   PerfCounter& GetOrCreateCounter(uint32_t cpu);
99 
clock_id()100   ClockTracker::ClockId clock_id() const { return clock_id_; }
101 
102  private:
is_timebase()103   bool is_timebase() const {
104     // This is what simpleperf uses for events that are not supposed to sample
105     // TODO(b/334978369): Determine if there is a better way to figure this out.
106     return attr_.sample_period < (1ull << 62);
107   }
108 
109   PerfCounter CreateCounter(uint32_t cpu) const;
110 
111   TraceProcessorContext* const context_;
112   const ClockTracker::ClockId clock_id_;
113   tables::PerfSessionTable::Id perf_session_id_;
114   perf_event_attr attr_;
115   std::optional<size_t> time_offset_from_start_;
116   std::optional<size_t> time_offset_from_end_;
117   std::optional<size_t> id_offset_from_start_;
118   std::optional<size_t> id_offset_from_end_;
119   size_t sample_id_size_;
120   std::unordered_map<uint32_t, PerfCounter> counters_;
121   std::string event_name_;
122 };
123 
124 }  // namespace perf_importer
125 }  // namespace perfetto::trace_processor
126 
127 #endif  // SRC_TRACE_PROCESSOR_IMPORTERS_PERF_PERF_EVENT_ATTR_H_
128