scripts/performance/topN_perf.py

3 #  Print the top N most executed functions in QEMU using perf.
5 #  topN_perf.py [-h] [-n] <number of displayed top functions>  -- \
9 #  [-h] - Print the script arguments help message.
10 #  [-n] - Specify the number of top functions to print.
11 #       - If this flag is not specified, the tool defaults to 25.
14 #  topN_perf.py -n 20 -- qemu-arm coulomb_double-arm
26 #  This program is distributed in the hope that it will be useful,
42     usage='topN_perf.py [-h] [-n] <number of displayed top functions >  -- '
46 parser.add_argument('-n', dest='top', type=int, default=25,
47                     help='Specify the number of top functions to print.')
77   -1: Allow use of (almost) all events by all users
85    kernel.perf_event_paranoid = -1
92 perf_record = subprocess.run((["perf", "record", "--output=/tmp/perf.data"] +
98     sys.exit(perf_record.stderr.decode("utf-8"))
103         ["perf", "report", "--input=/tmp/perf.data", "--stdio"],
110         sys.exit(perf_report.stderr.decode("utf-8"))
112 # Read the reported data to functions[]
113 functions = []  variable
117     functions = [line for line in data.readlines() if line and line[0]  variable
120 # Limit the number of top functions to "top"
121 number_of_top_functions = top if len(functions) > top else len(functions)
123 # Store the data of the top functions in top_functions[]
124 top_functions = functions[:number_of_top_functions]
131                                                          '-' * 4,
132                                                          '-' * 10,
133                                                          '-' * 30,
134                                                          '-' * 25))
136 # Print top N functions
137 for (index, function) in enumerate(top_functions, start=1):
140     function_name = function_data[-1]
141     function_invoker = ' '.join(function_data[2:-2])