1 //
2 // Copyright (C) 2021 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 //! Trace provider backed by ARM Coresight ETM, using simpleperf tool.
18 
19 use anyhow::{anyhow, Result};
20 use std::fs::{read_dir, remove_file};
21 use std::path::{Path, PathBuf};
22 use std::time::Duration;
23 use trace_provider::TraceProvider;
24 
25 use crate::trace_provider;
26 
27 static ETM_TRACEFILE_EXTENSION: &str = "etmtrace";
28 static ETM_PROFILE_EXTENSION: &str = "data";
29 
30 pub struct SimpleperfEtmTraceProvider {}
31 
32 impl TraceProvider for SimpleperfEtmTraceProvider {
get_name(&self) -> &'static str33     fn get_name(&self) -> &'static str {
34         "simpleperf_etm"
35     }
36 
is_ready(&self) -> bool37     fn is_ready(&self) -> bool {
38         simpleperf_profcollect::is_etm_device_available()
39     }
40 
trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration, binary_filter: &str)41     fn trace(&self, trace_dir: &Path, tag: &str, sampling_period: &Duration, binary_filter: &str) {
42         let trace_file = trace_provider::get_path(trace_dir, tag, ETM_TRACEFILE_EXTENSION);
43         // Record ETM data for kernel space only when it's not filtered out by binary_filter. So we
44         // can get more ETM data for user space when ETM data for kernel space isn't needed.
45         let event_name = if binary_filter.contains("kernel") { "cs-etm" } else { "cs-etm:u" };
46         let duration: String = sampling_period.as_secs_f64().to_string();
47         let args: Vec<&str> = vec![
48             "-a",
49             "-e",
50             event_name,
51             "--duration",
52             &duration,
53             "--decode-etm",
54             "--exclude-perf",
55             "--binary",
56             binary_filter,
57             "--no-dump-symbols",
58             "--no-dump-kernel-symbols",
59             "-o",
60             trace_file.to_str().unwrap(),
61         ];
62 
63         simpleperf_profcollect::run_record_cmd(&args);
64     }
65 
process(&self, trace_dir: &Path, profile_dir: &Path, binary_filter: &str) -> Result<()>66     fn process(&self, trace_dir: &Path, profile_dir: &Path, binary_filter: &str) -> Result<()> {
67         let is_etm_extension = |file: &PathBuf| {
68             file.extension()
69                 .and_then(|f| f.to_str())
70                 .filter(|ext| ext == &ETM_TRACEFILE_EXTENSION)
71                 .is_some()
72         };
73 
74         let process_trace_file = |trace_file: PathBuf| {
75             let mut profile_file = PathBuf::from(profile_dir);
76             profile_file.push(
77                 trace_file
78                     .file_name()
79                     .ok_or_else(|| anyhow!("Malformed trace path: {}", trace_file.display()))?,
80             );
81             profile_file.set_extension(ETM_PROFILE_EXTENSION);
82 
83             let args: Vec<&str> = vec![
84                 "-i",
85                 trace_file.to_str().unwrap(),
86                 "-o",
87                 profile_file.to_str().unwrap(),
88                 "--output",
89                 "branch-list",
90                 "--binary",
91                 binary_filter,
92             ];
93             simpleperf_profcollect::run_inject_cmd(&args);
94             remove_file(&trace_file)?;
95             Ok(())
96         };
97 
98         read_dir(trace_dir)?
99             .filter_map(|e| e.ok())
100             .map(|e| e.path())
101             .filter(|e| e.is_file())
102             .filter(is_etm_extension)
103             .try_for_each(process_trace_file)
104     }
105 
set_log_file(&self, filename: &Path)106     fn set_log_file(&self, filename: &Path) {
107         simpleperf_profcollect::set_log_file(filename);
108     }
109 
reset_log_file(&self)110     fn reset_log_file(&self) {
111         simpleperf_profcollect::reset_log_file();
112     }
113 }
114 
115 impl SimpleperfEtmTraceProvider {
supported() -> bool116     pub fn supported() -> bool {
117         simpleperf_profcollect::is_etm_driver_available()
118     }
119 }
120