test-ss.py

from __future__ import print_function
#
# This script needs to be run on startup
# qemu -kernel ${KERNEL} -s -S
# and then:
# gdb ${KERNEL}.vmlinux -x ${QEMU_SRC}/tests/guest-debug/test-ss.py
#
# This is a soak test for single-stepping which attempts to detect
# failed single-steps by single stepping a whole kernel.

import gdb
import re

def run_test():
    "Run through the tests one by one"

    print ("Stepping... until we fails")
    steps_taken = 0
    step_ok = True

    while step_ok:
        start_pc = gdb.parse_and_eval('$pc')
        result = gdb.execute("si", to_string=True)
        end_pc = gdb.parse_and_eval('$pc')

        if start_pc == end_pc:
            step_ok = False
        else:
            steps_taken += 1

        if steps_taken % 1000 == 0:
            print ("Stepping %d insns, currently @ %s" %
                   (steps_taken, end_pc))

    print ("Failed at %s (%s)" % (end_pc, result))

#
# This runs as the script it sourced (via -x)
#

try:
    print ("Connecting to remote")
    gdb.execute("target remote localhost:1234")

    # These are not very useful in scripts
    gdb.execute("set pagination off")
    gdb.execute("set confirm off")

    # Run the actual tests
    run_test()

except:
    print ("GDB Exception: %s" % (sys.exc_info()[0]))
    import code
    code.InteractiveConsole(locals=globals()).interact()
    raise

# Finally kill the inferior and exit gdb with a count of failures
gdb.execute("kill")
exit(failcount)