xref: /aosp_15_r20/external/perfetto/src/trace_processor/importers/ftrace/rss_stat_tracker.cc (revision 6dbdd20afdafa5e3ca9b8809fa73465d530080dc)
1 /*
2  * Copyright (C) 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 #include "src/trace_processor/importers/ftrace/rss_stat_tracker.h"
18 
19 #include <cstdint>
20 #include <optional>
21 
22 #include "perfetto/base/logging.h"
23 #include "src/trace_processor/importers/common/event_tracker.h"
24 #include "src/trace_processor/importers/common/process_tracker.h"
25 #include "src/trace_processor/storage/stats.h"
26 #include "src/trace_processor/storage/trace_storage.h"
27 #include "src/trace_processor/types/trace_processor_context.h"
28 
29 #include "protos/perfetto/trace/ftrace/ftrace_event.pbzero.h"
30 #include "protos/perfetto/trace/ftrace/kmem.pbzero.h"
31 #include "protos/perfetto/trace/ftrace/synthetic.pbzero.h"
32 
33 namespace perfetto::trace_processor {
34 namespace {
35 
36 using FtraceEvent = protos::pbzero::FtraceEvent;
37 
GetProcessMemoryKey(uint32_t member)38 const char* GetProcessMemoryKey(uint32_t member) {
39   switch (member) {
40     case 0:
41       return "rss.file";
42     case 1:
43       return "rss.anon";
44     case 2:
45       return "swap";
46     case 3:
47       return "rss.shmem";
48     case 4:
49       return "unreclaimable";
50     default:
51       return "unknown";
52   }
53 }
54 
55 }  // namespace
56 
RssStatTracker(TraceProcessorContext * context)57 RssStatTracker::RssStatTracker(TraceProcessorContext* context)
58     : context_(context) {}
59 
ParseRssStat(int64_t ts,uint32_t field_id,uint32_t pid,ConstBytes blob)60 void RssStatTracker::ParseRssStat(int64_t ts,
61                                   uint32_t field_id,
62                                   uint32_t pid,
63                                   ConstBytes blob) {
64   uint32_t member;
65   int64_t size;
66   std::optional<bool> curr;
67   std::optional<int64_t> mm_id;
68 
69   if (field_id == FtraceEvent::kRssStatFieldNumber) {
70     protos::pbzero::RssStatFtraceEvent::Decoder rss(blob.data, blob.size);
71 
72     member = static_cast<uint32_t>(rss.member());
73     size = rss.size();
74     if (rss.has_curr()) {
75       curr = std::make_optional(static_cast<bool>(rss.curr()));
76     }
77     if (rss.has_mm_id()) {
78       mm_id = std::make_optional(rss.mm_id());
79     }
80 
81     ParseRssStat(ts, pid, size, member, curr, mm_id);
82   } else if (field_id == FtraceEvent::kRssStatThrottledFieldNumber) {
83     protos::pbzero::RssStatThrottledFtraceEvent::Decoder rss(blob.data,
84                                                              blob.size);
85 
86     member = static_cast<uint32_t>(rss.member());
87     size = rss.size();
88     curr = std::make_optional(static_cast<bool>(rss.curr()));
89     mm_id = std::make_optional(rss.mm_id());
90 
91     ParseRssStat(ts, pid, size, member, curr, mm_id);
92   } else {
93     PERFETTO_DFATAL("Unexpected field id");
94   }
95 }
96 
ParseRssStat(int64_t ts,uint32_t pid,int64_t size,uint32_t member,std::optional<bool> curr,std::optional<int64_t> mm_id)97 void RssStatTracker::ParseRssStat(int64_t ts,
98                                   uint32_t pid,
99                                   int64_t size,
100                                   uint32_t member,
101                                   std::optional<bool> curr,
102                                   std::optional<int64_t> mm_id) {
103   const char* memory_key = GetProcessMemoryKey(member);
104   if (!memory_key) {
105     context_->storage->IncrementStats(stats::rss_stat_unknown_keys);
106     return;
107   }
108   if (size < 0) {
109     context_->storage->IncrementStats(stats::rss_stat_negative_size);
110     return;
111   }
112 
113   std::optional<UniqueTid> utid;
114   if (mm_id.has_value() && curr.has_value()) {
115     utid = FindUtidForMmId(*mm_id, *curr, pid);
116   } else {
117     utid = context_->process_tracker->GetOrCreateThread(pid);
118   }
119 
120   if (utid) {
121     context_->event_tracker->PushProcessCounterForThread(
122         EventTracker::RssStat{memory_key}, ts, static_cast<double>(size),
123         *utid);
124   } else {
125     context_->storage->IncrementStats(stats::rss_stat_unknown_thread_for_mm_id);
126   }
127 }
128 
FindUtidForMmId(int64_t mm_id,bool is_curr,uint32_t pid)129 std::optional<UniqueTid> RssStatTracker::FindUtidForMmId(int64_t mm_id,
130                                                          bool is_curr,
131                                                          uint32_t pid) {
132   // If curr is true, we can just overwrite the state in the map and return
133   // the utid correspodning to |pid|.
134   if (is_curr) {
135     UniqueTid utid = context_->process_tracker->GetOrCreateThread(pid);
136     mm_id_to_utid_[mm_id] = utid;
137     return utid;
138   }
139 
140   // If curr is false, try and lookup the utid we previously saw for this
141   // mm id.
142   auto* it = mm_id_to_utid_.Find(mm_id);
143   if (!it)
144     return std::nullopt;
145 
146   // If the utid in the map is the same as our current utid but curr is false,
147   // that means we are in the middle of a process changing mm structs (i.e. in
148   // the middle of a vfork + exec). Therefore, we should discard the association
149   // of this vm struct with this thread.
150   const UniqueTid mm_utid = *it;
151   const UniqueTid utid = context_->process_tracker->GetOrCreateThread(pid);
152   if (mm_utid == utid) {
153     mm_id_to_utid_.Erase(mm_id);
154     return std::nullopt;
155   }
156 
157   // Verify that the utid in the map is still alive. This can happen if an mm
158   // struct we saw in the past is about to be reused after thread but we don't
159   // know the new process that struct will be associated with.
160   if (!context_->process_tracker->IsThreadAlive(mm_utid)) {
161     mm_id_to_utid_.Erase(mm_id);
162     return std::nullopt;
163   }
164 
165   // This case happens when a process is changing the VM of another process and
166   // we know that the utid corresponding to the target process. Just return that
167   // utid.
168   return mm_utid;
169 }
170 
171 }  // namespace perfetto::trace_processor
172