1import os 2from autotest_lib.client.bin import utils 3 4 5class Tracer(object): 6 """ 7 Common interface for tracing. 8 """ 9 10 tracing_dir = None 11 12 def trace_config(self, path, value): 13 """ 14 Write value to a tracing config file under self.tracing_dir. 15 """ 16 path = os.path.join(self.tracing_dir, path) 17 utils.open_write_close(path, value) 18 19 def warmup(self, buffer_size_kb): 20 pass 21 def cleanup(self): 22 pass 23 def start_tracing(self): 24 pass 25 def stop_tracing(self): 26 pass 27 def gather_stats(self, results): 28 pass 29 def reset_tracing(self): 30 pass 31