scripts/performance: Add dissect.py script

Python script that dissects QEMU execution into three main phases:
code generation, JIT execution and helpers execution.

Syntax:
dissect.py [-h] -- <qemu executable> [<qemu executable options>] \
                 <target executable> [<target executable options>]

[-h] - Print the script arguments help message.

Example of usage:
dissect.py -- qemu-arm coulomb_double-arm

Example output:
Total Instructions:        4,702,865,362

Code Generation:             115,819,309	 2.463%
JIT Execution:             1,081,980,528	23.007%
Helpers:                   3,505,065,525	74.530%

Signed-off-by: Ahmed Karaman <ahmedkhaledkaraman@gmail.com>
Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200709052055.2650-2-ahmedkhaledkaraman@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

scripts/performance/dissect.py

@@ -0,0 +1,166 @@
+#!/usr/bin/env python3
+
+#  Print the percentage of instructions spent in each phase of QEMU
+#  execution.
+#
+#  Syntax:
+#  dissect.py [-h] -- <qemu executable> [<qemu executable options>] \
+#                   <target executable> [<target executable options>]
+#
+#  [-h] - Print the script arguments help message.
+#
+#  Example of usage:
+#  dissect.py -- qemu-arm coulomb_double-arm
+#
+#  This file is a part of the project "TCG Continuous Benchmarking".
+#
+#  Copyright (C) 2020  Ahmed Karaman <ahmedkhaledkaraman@gmail.com>
+#  Copyright (C) 2020  Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
+#
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+import argparse
+import os
+import subprocess
+import sys
+import tempfile
+
+
+def get_JIT_line(callgrind_data):
+    """
+    Search for the first instance of the JIT call in
+    the callgrind_annotate output when ran using --tree=caller
+    This is equivalent to the self number of instructions of JIT.
+
+    Parameters:
+    callgrind_data (list): callgrind_annotate output
+
+    Returns:
+    (int): Line number
+    """
+    line = -1
+    for i in range(len(callgrind_data)):
+        if callgrind_data[i].strip('\n') and \
+                callgrind_data[i].split()[-1] == "[???]":
+            line = i
+            break
+    if line == -1:
+        sys.exit("Couldn't locate the JIT call ... Exiting.")
+    return line
+
+
+def main():
+    # Parse the command line arguments
+    parser = argparse.ArgumentParser(
+        usage='dissect.py [-h] -- '
+        '<qemu executable> [<qemu executable options>] '
+        '<target executable> [<target executable options>]')
+
+    parser.add_argument('command', type=str, nargs='+', help=argparse.SUPPRESS)
+
+    args = parser.parse_args()
+
+    # Extract the needed variables from the args
+    command = args.command
+
+    # Insure that valgrind is installed
+    check_valgrind = subprocess.run(
+        ["which", "valgrind"], stdout=subprocess.DEVNULL)
+    if check_valgrind.returncode:
+        sys.exit("Please install valgrind before running the script.")
+
+    # Save all intermediate files in a temporary directory
+    with tempfile.TemporaryDirectory() as tmpdirname:
+        # callgrind output file path
+        data_path = os.path.join(tmpdirname, "callgrind.data")
+        # callgrind_annotate output file path
+        annotate_out_path = os.path.join(tmpdirname, "callgrind_annotate.out")
+
+        # Run callgrind
+        callgrind = subprocess.run((["valgrind",
+                                     "--tool=callgrind",
+                                     "--callgrind-out-file=" + data_path]
+                                    + command),
+                                   stdout=subprocess.DEVNULL,
+                                   stderr=subprocess.PIPE)
+        if callgrind.returncode:
+            sys.exit(callgrind.stderr.decode("utf-8"))
+
+        # Save callgrind_annotate output
+        with open(annotate_out_path, "w") as output:
+            callgrind_annotate = subprocess.run(
+                ["callgrind_annotate", data_path, "--tree=caller"],
+                stdout=output,
+                stderr=subprocess.PIPE)
+            if callgrind_annotate.returncode:
+                sys.exit(callgrind_annotate.stderr.decode("utf-8"))
+
+        # Read the callgrind_annotate output to callgrind_data[]
+        callgrind_data = []
+        with open(annotate_out_path, 'r') as data:
+            callgrind_data = data.readlines()
+
+        # Line number with the total number of instructions
+        total_instructions_line_number = 20
+        # Get the total number of instructions
+        total_instructions_line_data = \
+            callgrind_data[total_instructions_line_number]
+        total_instructions = total_instructions_line_data.split()[0]
+        total_instructions = int(total_instructions.replace(',', ''))
+
+        # Line number with the JIT self number of instructions
+        JIT_self_instructions_line_number = get_JIT_line(callgrind_data)
+        # Get the JIT self number of instructions
+        JIT_self_instructions_line_data = \
+            callgrind_data[JIT_self_instructions_line_number]
+        JIT_self_instructions = JIT_self_instructions_line_data.split()[0]
+        JIT_self_instructions = int(JIT_self_instructions.replace(',', ''))
+
+        # Line number with the JIT self + inclusive number of instructions
+        # It's the line above the first JIT call when running with --tree=caller
+        JIT_total_instructions_line_number = JIT_self_instructions_line_number-1
+        # Get the JIT self + inclusive number of instructions
+        JIT_total_instructions_line_data = \
+            callgrind_data[JIT_total_instructions_line_number]
+        JIT_total_instructions = JIT_total_instructions_line_data.split()[0]
+        JIT_total_instructions = int(JIT_total_instructions.replace(',', ''))
+
+        # Calculate number of instructions in helpers and code generation
+        helpers_instructions = JIT_total_instructions-JIT_self_instructions
+        code_generation_instructions = total_instructions-JIT_total_instructions
+
+        # Print results (Insert commas in large numbers)
+        # Print total number of instructions
+        print('{:<20}{:>20}\n'.
+              format("Total Instructions:",
+                     format(total_instructions, ',')))
+        # Print code generation instructions and percentage
+        print('{:<20}{:>20}\t{:>6.3f}%'.
+              format("Code Generation:",
+                     format(code_generation_instructions, ","),
+                     (code_generation_instructions / total_instructions) * 100))
+        # Print JIT instructions and percentage
+        print('{:<20}{:>20}\t{:>6.3f}%'.
+              format("JIT Execution:",
+                     format(JIT_self_instructions, ","),
+                     (JIT_self_instructions / total_instructions) * 100))
+        # Print helpers instructions and percentage
+        print('{:<20}{:>20}\t{:>6.3f}%'.
+              format("Helpers:",
+                     format(helpers_instructions, ","),
+                     (helpers_instructions/total_instructions)*100))
+
+
+if __name__ == "__main__":
+    main()