1# 2# Copyright (C) 2016 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 16import os 17import tempfile 18import shutil 19import subprocess 20import logging 21 22PATH_SYSTRACE_SCRIPT = os.path.join('tools/external/chromium-trace', 23 'systrace.py') 24EXPECTED_START_STDOUT = 'Starting tracing' 25 26 27class SystraceController(object): 28 '''A util to start/stop systrace through shell command. 29 30 Attributes: 31 _android_vts_path: string, path to android-vts 32 _path_output: string, systrace temporally output path 33 _path_systrace_script: string, path to systrace controller python script 34 _device_serial: string, device serial string 35 _subprocess: subprocess.Popen, a subprocess objects of systrace shell command 36 is_valid: boolean, whether the current environment setting for 37 systrace is valid 38 process_name: string, process name to trace. The value can be empty. 39 ''' 40 41 def __init__(self, android_vts_path, device_serial, process_name=''): 42 self._android_vts_path = android_vts_path 43 self._path_output = None 44 self._subprocess = None 45 self._device_serial = device_serial 46 if not device_serial: 47 logging.warning( 48 'Device serial is not provided for systrace. ' 49 'Tool will not start if multiple devices are connected.') 50 self.process_name = process_name 51 self._path_systrace_script = os.path.join(android_vts_path, 52 PATH_SYSTRACE_SCRIPT) 53 self.is_valid = os.path.exists(self._path_systrace_script) 54 if not self.is_valid: 55 logging.error('invalid systrace script path: %s', 56 self._path_systrace_script) 57 58 @property 59 def is_valid(self): 60 ''''returns whether the current environment setting is valid''' 61 return self._is_valid 62 63 @is_valid.setter 64 def is_valid(self, is_valid): 65 ''''Set valid status''' 66 self._is_valid = is_valid 67 68 @property 69 def process_name(self): 70 ''''returns process name''' 71 return self._process_name 72 73 @process_name.setter 74 def process_name(self, process_name): 75 ''''Set process name''' 76 self._process_name = process_name 77 78 @property 79 def has_output(self): 80 ''''returns whether output file exists and not empty. 81 82 Returns: 83 False if output path is not specified, or output file doesn't exist, or output 84 file size is zero; True otherwise. 85 ''' 86 if not self._path_output: 87 logging.warning('systrace output path is empty.') 88 return False 89 90 try: 91 if os.path.getsize(self._path_output) == 0: 92 logging.warning('systrace output file is empty.') 93 return False 94 except OSError: 95 logging.info('systrace output file does not exist.') 96 return False 97 return True 98 99 def Start(self): 100 '''Start systrace process. 101 102 Use shell command to start a python systrace script 103 104 Returns: 105 True if successfully started systrace; False otherwise. 106 ''' 107 self._subprocess = None 108 self._path_output = None 109 110 if not self.is_valid: 111 logging.error( 112 'Cannot start systrace: configuration is not correct for %s.', 113 self.process_name) 114 return False 115 116 # TODO: check target device for compatibility (e.g. has systrace hooks) 117 process_name_arg = '' 118 if self.process_name: 119 process_name_arg = '-a %s' % self.process_name 120 121 device_serial_arg = '' 122 if self._device_serial: 123 device_serial_arg = '--serial=%s' % self._device_serial 124 125 tmp_dir = tempfile.mkdtemp() 126 tmp_filename = self.process_name if self.process_name else 'systrace' 127 self._path_output = str(os.path.join(tmp_dir, tmp_filename + '.html')) 128 129 cmd = ('python -u {script} hal sched ' 130 '{process_name_arg} {serial} -o {output}').format( 131 script=self._path_systrace_script, 132 process_name_arg=process_name_arg, 133 serial=device_serial_arg, 134 output=self._path_output) 135 process = subprocess.Popen( 136 str(cmd), 137 shell=True, 138 stdin=subprocess.PIPE, 139 stdout=subprocess.PIPE, 140 stderr=subprocess.PIPE) 141 142 line = '' 143 success = False 144 while process.poll() is None: 145 line += process.stdout.read(1) 146 147 if not line: 148 break 149 elif EXPECTED_START_STDOUT in line: 150 success = True 151 break 152 153 if not success: 154 logging.error('Failed to start systrace on process %s', 155 self.process_name) 156 stdout, stderr = process.communicate() 157 logging.error('stdout: %s', line + stdout) 158 logging.error('stderr: %s', stderr) 159 logging.error('ret_code: %s', process.returncode) 160 return False 161 162 self._subprocess = process 163 logging.info('Systrace started for %s', self.process_name) 164 return True 165 166 def Stop(self): 167 '''Stop systrace process. 168 169 Returns: 170 True if successfully stopped systrace or systrace already stopped; 171 False otherwise. 172 ''' 173 if not self.is_valid: 174 logging.warn( 175 'Cannot stop systrace: systrace was not started for %s.', 176 self.process_name) 177 return False 178 179 if not self._subprocess: 180 logging.info('Systrace already stopped.') 181 return True 182 183 # Press enter to stop systrace script 184 self._subprocess.stdin.write('\n') 185 self._subprocess.stdin.flush() 186 # Wait for output to be written down 187 # TODO: use subprocess.TimeoutExpired after upgrading to python >3.3 188 out, err = self._subprocess.communicate() 189 logging.info('Systrace stopped for %s', self.process_name) 190 logging.info('Systrace stdout: %s', out) 191 logging.info('Systrace stderr: %s', err) 192 193 self._subprocess = None 194 195 return True 196 197 def ReadLastOutput(self): 198 '''Read systrace output html. 199 200 Returns: 201 string, data of systrace html output. None if failed to read. 202 ''' 203 if not self.is_valid or not self._subprocess: 204 logging.warn( 205 'Cannot read output: systrace was not started for %s.', 206 self.process_name) 207 return None 208 209 if not self.has_output: 210 logging.error( 211 'systrace did not started/ended correctly. Output is empty.') 212 return False 213 214 try: 215 with open(self._path_output, 'r') as f: 216 data = f.read() 217 logging.info('Systrace output length for %s: %s', process_name, 218 len(data)) 219 return data 220 except Exception as e: 221 logging.error('Cannot read output: file open failed, %s', e) 222 return None 223 224 def SaveLastOutput(self, report_path=None): 225 if not report_path: 226 logging.error('report path supplied is None') 227 return False 228 report_path = str(report_path) 229 230 if not self.has_output: 231 logging.error( 232 'systrace did not started/ended correctly. Output is empty.') 233 return False 234 235 parent_dir = os.path.dirname(report_path) 236 if not os.path.exists(parent_dir): 237 try: 238 os.makedirs(parent_dir) 239 except Exception as e: 240 logging.error('error happened while creating directory: %s', e) 241 return False 242 243 try: 244 shutil.copy(self._path_output, report_path) 245 except Exception as e: # TODO(yuexima): more specific error catch 246 logging.error('failed to copy output to report path: %s', e) 247 return False 248 249 return True 250 251 def ClearLastOutput(self): 252 '''Clear systrace output html. 253 254 Since output are created in temp directories, this step is optional. 255 256 Returns: 257 True if successfully deleted temp output file; False otherwise. 258 ''' 259 260 if self._path_output: 261 try: 262 shutil.rmtree(os.path.basename(self._path_output)) 263 except Exception as e: 264 logging.error('failed to remove systrace output file. %s', e) 265 return False 266 finally: 267 self._path_output = None 268 269 return True 270