xref: /aosp_15_r20/external/perfetto/src/traced/probes/ps/process_stats_data_source.h (revision 6dbdd20afdafa5e3ca9b8809fa73465d530080dc)
1 /*
2  * Copyright (C) 2018 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_TRACED_PROBES_PS_PROCESS_STATS_DATA_SOURCE_H_
18 #define SRC_TRACED_PROBES_PS_PROCESS_STATS_DATA_SOURCE_H_
19 
20 #include <functional>
21 #include <limits>
22 #include <memory>
23 #include <unordered_map>
24 #include <utility>
25 #include <vector>
26 
27 #include "perfetto/base/flat_set.h"
28 #include "perfetto/ext/base/scoped_file.h"
29 #include "perfetto/ext/base/weak_ptr.h"
30 #include "perfetto/ext/tracing/core/basic_types.h"
31 #include "perfetto/ext/tracing/core/trace_writer.h"
32 #include "perfetto/tracing/core/forward_decls.h"
33 #include "src/traced/probes/probes_data_source.h"
34 
35 namespace perfetto {
36 
37 namespace base {
38 class TaskRunner;
39 }
40 
41 namespace protos {
42 namespace pbzero {
43 class ProcessTree;
44 class ProcessStats;
45 class ProcessStats_Process;
46 }  // namespace pbzero
47 }  // namespace protos
48 
49 class ProcessStatsDataSource : public ProbesDataSource {
50  public:
51   static const ProbesDataSource::Descriptor descriptor;
52 
53   ProcessStatsDataSource(base::TaskRunner*,
54                          TracingSessionID,
55                          std::unique_ptr<TraceWriter> writer,
56                          const DataSourceConfig&);
57   ~ProcessStatsDataSource() override;
58 
59   base::WeakPtr<ProcessStatsDataSource> GetWeakPtr() const;
60   void WriteAllProcesses();
61   void OnPids(const base::FlatSet<int32_t>& pids);
62   void OnRenamePids(const base::FlatSet<int32_t>& pids);
63   void OnFds(const base::FlatSet<std::pair<pid_t, uint64_t>>& fds);
64 
65   // ProbesDataSource implementation.
66   void Start() override;
67   void Flush(FlushRequestID, std::function<void()> callback) override;
68   void ClearIncrementalState() override;
69 
on_demand_dumps_enabled()70   bool on_demand_dumps_enabled() const { return enable_on_demand_dumps_; }
71 
72   // Virtual for testing.
73   virtual const char* GetProcMountpoint();
74   virtual base::ScopedDir OpenProcDir();
75   virtual std::string ReadProcPidFile(int32_t pid, const std::string& file);
76 
77  private:
78   struct CachedProcessStats {
79     uint32_t vm_size_kb = std::numeric_limits<uint32_t>::max();
80     uint32_t vm_rss_kb = std::numeric_limits<uint32_t>::max();
81     uint32_t rss_anon_kb = std::numeric_limits<uint32_t>::max();
82     uint32_t rss_file_kb = std::numeric_limits<uint32_t>::max();
83     uint32_t rss_shmem_kb = std::numeric_limits<uint32_t>::max();
84     uint32_t vm_swap_kb = std::numeric_limits<uint32_t>::max();
85     uint32_t vm_locked_kb = std::numeric_limits<uint32_t>::max();
86     uint32_t vm_hvm_kb = std::numeric_limits<uint32_t>::max();
87     int32_t oom_score_adj = std::numeric_limits<int32_t>::max();
88     uint32_t smr_rss_kb = std::numeric_limits<uint32_t>::max();
89     uint32_t smr_pss_kb = std::numeric_limits<uint32_t>::max();
90     uint32_t smr_pss_anon_kb = std::numeric_limits<uint32_t>::max();
91     uint32_t smr_pss_file_kb = std::numeric_limits<uint32_t>::max();
92     uint32_t smr_pss_shmem_kb = std::numeric_limits<uint32_t>::max();
93     uint32_t smr_swap_pss_kb = std::numeric_limits<uint32_t>::max();
94     uint64_t runtime_user_mode_ns = std::numeric_limits<uint64_t>::max();
95     uint64_t runtime_kernel_mode_ns = std::numeric_limits<uint64_t>::max();
96     // file descriptors
97     base::FlatSet<uint64_t> seen_fds;
98   };
99 
100   // Common functions.
101   ProcessStatsDataSource(const ProcessStatsDataSource&) = delete;
102   ProcessStatsDataSource& operator=(const ProcessStatsDataSource&) = delete;
103 
104   void StartNewPacketIfNeeded();
105   void FinalizeCurPacket();
106   protos::pbzero::ProcessTree* GetOrCreatePsTree();
107   protos::pbzero::ProcessStats* GetOrCreateStats();
108   protos::pbzero::ProcessStats_Process* GetOrCreateStatsProcess(int32_t pid);
109 
110   // Functions for snapshotting process/thread long-term info and relationships.
111   bool WriteProcess(int32_t pid,
112                     const std::string& proc_status,
113                     const std::string& proc_stat);
114   void WriteThread(int32_t tid, int32_t tgid);
115   void WriteDetailedThread(int32_t tid,
116                            int32_t tgid,
117                            const std::string& proc_status);
118   void WriteProcessOrThread(int32_t pid);
119 
120   // Functions for periodically sampling process stats/counters.
121   static void Tick(base::WeakPtr<ProcessStatsDataSource>);
122   void WriteAllProcessStats();
123   bool WriteProcessRuntimes(int32_t pid, const std::string& proc_stat);
124   bool WriteMemCounters(int32_t pid, const std::string& proc_status);
125   void WriteFds(int32_t pid);
126   void WriteSingleFd(int32_t pid, uint64_t fd);
127 
128   // Scans /proc/pid/status and writes the ProcessTree packet for input pids.
129   void WriteProcessTree(const base::FlatSet<int32_t>&);
130 
131   // Read and "latch" the current procfs scan-start timestamp, which
132   // we reset only in FinalizeCurPacket.
133   uint64_t CacheProcFsScanStartTimestamp();
134 
135   // Common fields used for both process/tree relationships and stats/counters.
136   base::TaskRunner* const task_runner_;
137   std::unique_ptr<TraceWriter> writer_;
138   TraceWriter::TracePacketHandle cur_packet_;
139 
140   // Cached before-scan timestamp; zero means cached time is absent.
141   // By the time we create the trace packet into which we dump procfs
142   // scan results, we've already read at least one bit of data from
143   // procfs, and by that point, it's too late to snap a timestamp from
144   // before we started looking at procfs at all, which is what trace
145   // analysis wants.  To solve this problem, we record the scan-start
146   // timestamp here when we first open something in procfs and use
147   // that time when we create the packet.
148   // We reset this field after each FinalizeCurPacket().
149   uint64_t cur_procfs_scan_start_timestamp_ = 0;
150 
151   // Fields for keeping track of the state of process/tree relationships.
152   protos::pbzero::ProcessTree* cur_ps_tree_ = nullptr;
153   bool record_thread_names_ = false;
154   bool enable_on_demand_dumps_ = true;
155   bool dump_all_procs_on_start_ = false;
156   bool resolve_process_fds_ = false;
157   bool scan_smaps_rollup_ = false;
158   bool record_process_age_ = false;
159   bool record_process_runtime_ = false;
160 
161   // This set contains PIDs as per the Linux kernel notion of a PID (which is
162   // really a TID). In practice this set will contain all TIDs for all processes
163   // seen, not just the main thread id (aka thread group ID).
164   struct SeenPid {
165     int32_t pid;
166     int32_t tgid;
167 
pidSeenPid168     SeenPid(int32_t _pid, int32_t _tgid = 0) : pid(_pid), tgid(_tgid) {}
169     // TODO(rsavitski): add comparator support to FlatSet
170     bool operator==(const SeenPid& other) const { return pid == other.pid; }
171     bool operator<(const SeenPid& other) const { return pid < other.pid; }
172   };
173   base::FlatSet<SeenPid> seen_pids_;
174 
175   // Fields for keeping track of the periodic stats/counters.
176   uint32_t poll_period_ms_ = 0;
177   uint64_t cache_ticks_ = 0;
178   protos::pbzero::ProcessStats* cur_ps_stats_ = nullptr;
179   protos::pbzero::ProcessStats_Process* cur_ps_stats_process_ = nullptr;
180   std::vector<bool> skip_mem_for_pids_;
181 
182   // Cached process stats per process. Cleared every |cache_ttl_ticks_| *
183   // |poll_period_ms_| ms.
184   uint32_t process_stats_cache_ttl_ticks_ = 0;
185   std::unordered_map<int32_t, CachedProcessStats> process_stats_cache_;
186 
187   // If true, the next trace packet will have the |incremental_state_cleared|
188   // flag set. Set initially and when handling a ClearIncrementalState call.
189   bool did_clear_incremental_state_ = true;
190 
191   base::WeakPtrFactory<ProcessStatsDataSource> weak_factory_;  // Keep last.
192 };
193 
194 }  // namespace perfetto
195 
196 #endif  // SRC_TRACED_PROBES_PS_PROCESS_STATS_DATA_SOURCE_H_
197