[CRIU] [PATCH] test, pipes: Exhaustive test of shared pipes
Kirill Tkhai
ktkhai at virtuozzo.com
Mon Dec 12 04:46:32 PST 2016
On 12.12.2016 15:46, Pavel Emelyanov wrote:
> On 12/12/2016 01:04 PM, Kirill Tkhai wrote:
>> On 09.12.2016 16:59, Pavel Emelyanov wrote:
>>> So, here's the next test that just enumerates all possible states and checks
>>> that CRIU C/R-s it well. This time -- pipes. The goal of the test is to load
>>> the fd-sharing engine, so pipes are chosen, as they not only generate shared
>>> struct files, but also produce 2 descriptors in CRIU's fdesc->open callback
>>> which is handled separately.
>>>
>>> It's implemented slightly differently from the unix test, since we don't want
>>> to check sequences of syscalls on objects, we need to check the task to pipe
>>> relations in all possible ways.
>>>
>>> The 'state' is several tasks, several pipes and each generated test includes
>>> pipe ends sitting in all possible combinations in the tasks' FDTs.
>>>
>>> Also note, that states, that seem to be equal to each other, e.g. pipe between
>>> tasks A->B and pipe B->A, are really different as CRIU picks the pipe-restorer
>>> based in task PIDs. So whether the picked task has read end or write end at
>>> his FDT makes a difference on restore.
>>>
>>> Number of tasks is limited with --tasks option, number of pipes with the
>>> --pipes one. Test just runs all -- generates states, makes them and C/R-s
>>> them. To check the restored result the /proc/pid/fd/ and /proc/pid/fdinfo/
>>> for all restored tasks is analyzed.
>>>
>>> Right now CRIU works OK for --tasks 2 --pipes 2 (for more -- didn't check).
>>> Kirill, please, check that your patches pass this test.
>>
>> I applied the test to criu-dev (without my patches) and run it:
>>
>> ~/criu# python ./test/exhaustive/pipe.py --tasks 2 --pipes 2
>> Checking [(0, 0), (0, 0)]
>> Make pipes
>> Make pipes for 0
>> Make pipes for 1
>> Wait for C/R
>> C/R test
>> `- dump fail
>> Wake up test
>> Done (1, pid == 23208)
>> FAIL
>>
>> Hm... Do I run it in a wrong way?
>
> Did you build criu before running the test?
Yes, it's definitely built:
root at pro:/home/kirill/criu# file criu/criu
criu/criu: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=9933205650ef97e01e3258b42dc41eedb9e3efdd, not stripped
root at pro:/home/kirill/criu# python ./test/exhaustive/pipe.py --tasks 2 --pipes 2
Checking [(0, 0), (0, 0)]
Make pipes
Make pipes for 0
Make pipes for 1
Wait for C/R
C/R test
`- dump fail
Wake up test
Done (1, pid == 29464)
FAIL
>>> TODO:
>>>
>>> - Randomize FDs under which tasks see the pipes. Now all tasks if they have
>>> some pipe, all see it under the same set of FDs.
>>>
>>> Signed-off-by: Pavel Emelyanov <xemul at virtuozzo.com>
>>> ---
>>> test/exhaustive/pipe.py | 270 ++++++++++++++++++++++++++++++++++++++++++++++++
>>> 1 file changed, 270 insertions(+)
>>> create mode 100755 test/exhaustive/pipe.py
>>>
>>> diff --git a/test/exhaustive/pipe.py b/test/exhaustive/pipe.py
>>> new file mode 100755
>>> index 0000000..4e94cab
>>> --- /dev/null
>>> +++ b/test/exhaustive/pipe.py
>>> @@ -0,0 +1,270 @@
>>> +#!/usr/bin/env python
>>> +
>>> +import argparse
>>> +import os
>>> +import signal
>>> +import socket
>>> +import time
>>> +import sys
>>> +import subprocess
>>> +
>>> +criu_bin='../../criu/criu'
>>> +
>>> +def mix(nr_tasks, nr_pipes):
>>> + # Returned is the list of combinations.
>>> + # Each combination is the lists of pipe descriptors.
>>> + # Each pipe descriptor is a 2-elemtn tuple, that contains values
>>> + # for R and W ends of pipes, each being a bit-field denoting in
>>> + # which tasks the respective end should be opened or not.
>>> +
>>> + # First -- make a full set of combinations for a single pipe.
>>> + max_idx = 1 << nr_tasks
>>> + pipe_mix = [[(r, w)] for r in xrange(0, max_idx) for w in xrange(0, max_idx)]
>>> +
>>> + # Now, for every pipe throw another one into the game making
>>> + # all possible combinations of what was seen before with the
>>> + # newbie.
>>> + pipes_mix = pipe_mix
>>> + for t in xrange(1, nr_pipes):
>>> + pipes_mix = [ o + n for o in pipes_mix for n in pipe_mix ]
>>> +
>>> + return pipes_mix
>>> +
>>> +
>>> +# Called by a test sub-process. It just closes the not needed ends
>>> +# of pipes and sleeps waiting for death.
>>> +def make_pipes(task_nr, nr_pipes, pipes, comb, status_pipe):
>>> + print '\t\tMake pipes for %d' % task_nr
>>> + # We need to make sure that pipes have their
>>> + # ends according to comb for task_nr
>>> +
>>> + for i in xrange(0, nr_pipes):
>>> + # Read end
>>> + if not (comb[i][0] & (1 << task_nr)):
>>> + os.close(pipes[i][0])
>>> + # Write end
>>> + if not (comb[i][1] & (1 << task_nr)):
>>> + os.close(pipes[i][1])
>>> +
>>> + os.write(status_pipe, '0')
>>> + os.close(status_pipe)
>>> + while True:
>>> + time.sleep(100)
>>> +
>>> +
>>> +def get_pipe_ino(pid, fd):
>>> + try:
>>> + return os.stat('/proc/%d/fd/%d' % (pid, fd)).st_ino
>>> + except:
>>> + return None
>>> +
>>> +
>>> +def get_pipe_rw(pid, fd):
>>> + for l in open('/proc/%d/fdinfo/%d' % (pid, fd)):
>>> + if l.startswith('flags:'):
>>> + f = l.split(None, 1)[1][-2]
>>> + if f == '0':
>>> + return 0 # Read
>>> + elif f == '1':
>>> + return 1 # Write
>>> + break
>>> +
>>> + raise Exception('Unexpected fdinfo contents')
>>> +
>>> +
>>> +def check_pipe_y(pid, fd, rw, inos):
>>> + ino = get_pipe_ino(pid, fd)
>>> + if ino == None:
>>> + return 'missing '
>>> + if not inos.has_key(fd):
>>> + inos[fd] = ino
>>> + elif inos[fd] != ino:
>>> + return 'wrong '
>>> + mod = get_pipe_rw(pid, fd)
>>> + if mod != rw:
>>> + return 'badmode '
>>> + return None
>>> +
>>> +
>>> +def check_pipe_n(pid, fd):
>>> + ino = get_pipe_ino(pid, fd)
>>> + if ino == None:
>>> + return None
>>> + else:
>>> + return 'present '
>>> +
>>> +
>>> +def check_pipe_end(kids, fd, comb, rw, inos):
>>> + t_nr = 0
>>> + for t_pid in kids:
>>> + if comb & (1 << t_nr):
>>> + res = check_pipe_y(t_pid, fd, rw, inos)
>>> + else:
>>> + res = check_pipe_n(t_pid, fd)
>>> + if res != None:
>>> + return res + 'kid(%d)' % t_nr
>>> + t_nr += 1
>>> + return None
>>> +
>>> +
>>> +def check_pipe(kids, fds, comb, inos):
>>> + for e in (0, 1): # 0 == R, 1 == W, see get_pipe_rw()
>>> + res = check_pipe_end(kids, fds[e], comb[e], e, inos)
>>> + if res != None:
>>> + return res + 'end(%d)' % e
>>> + return None
>>> +
>>> +def check_pipes(kids, pipes, comb):
>>> + # Kids contain pids
>>> + # Pipes contain pipe FDs
>>> + # Comb contain list of pairs of bits for RW ends
>>> + p_nr = 0
>>> + p_inos = {}
>>> + for p_fds in pipes:
>>> + res = check_pipe(kids, p_fds, comb[p_nr], p_inos)
>>> + if res != None:
>>> + return res + 'pipe(%d)' % p_nr
>>> + p_nr += 1
>>> +
>>> + return None
>>> +
>>> +
>>> +# Run by test main process. It opens pipes, then forks kids that
>>> +# will contain needed pipe ends, then report back that it's ready
>>> +# and waits for a signal (unix socket message) to start checking
>>> +# the kids' FD tables.
>>> +def make_comb(comb, opts, status_pipe):
>>> + print '\tMake pipes'
>>> + # 1st -- make needed pipes
>>> + pipes = []
>>> + for p in xrange(0, opts.pipes):
>>> + pipes.append(os.pipe())
>>> +
>>> + # Fork the kids that'll make pipes
>>> + kc_pipe = os.pipe()
>>> + kids = []
>>> + for t in xrange(0, opts.tasks):
>>> + pid = os.fork()
>>> + if pid == 0:
>>> + os.close(status_pipe)
>>> + os.close(kc_pipe[0])
>>> + make_pipes(t, opts.pipes, pipes, comb, kc_pipe[1])
>>> + sys.exit(1)
>>> + kids.append(pid)
>>> +
>>> + os.close(kc_pipe[1])
>>> + for p in pipes:
>>> + os.close(p[0])
>>> + os.close(p[1])
>>> +
>>> + # Wait for kids to get ready
>>> + k_res = ''
>>> + while True:
>>> + v = os.read(kc_pipe[0], 16)
>>> + if v == '':
>>> + break
>>> + k_res += v
>>> + os.close(kc_pipe[0])
>>> +
>>> + ex_code = 1
>>> + if k_res == '0' * opts.tasks:
>>> + print '\tWait for C/R'
>>> + cmd_sk = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM, 0)
>>> + cmd_sk.bind('\0CRIUPCSK')
>>> +
>>> + # Kids are ready, so is socket for kicking us. Notify the
>>> + # parent task that we are good to go.
>>> + os.write(status_pipe, '0')
>>> + os.close(status_pipe)
>>> + v = cmd_sk.recv(16)
>>> + if v == '0':
>>> + print '\tCheck pipes'
>>> + res = check_pipes(kids, pipes, comb)
>>> + if res == None:
>>> + ex_code = 0
>>> + else:
>>> + print '\tFAIL %s' % res
>>> +
>>> + # Just kill kids, all checks are done by us, we don't need'em any more
>>> + for t in kids:
>>> + os.kill(t, signal.SIGKILL)
>>> + os.waitpid(t, 0)
>>> +
>>> + return ex_code
>>> +
>>> +
>>> +def cr_test(pid):
>>> + print 'C/R test'
>>> + img_dir = 'pimg_%d' % pid
>>> + try:
>>> + os.mkdir(img_dir)
>>> + subprocess.check_call([criu_bin, 'dump', '-t', '%d' % pid, '-D', img_dir, '-o', 'dump.log', '-v4', '-j'])
>>> + except:
>>> + print '`- dump fail'
>>> + return False
>>> +
>>> + try:
>>> + os.waitpid(pid, 0)
>>> + subprocess.check_call([criu_bin, 'restore', '-D', img_dir, '-o', 'rst.log', '-v4', '-j', '-d', '-S'])
>>> + except:
>>> + print '`- restore fail'
>>> + return False
>>> +
>>> + return True
>>> +
>>> +
>>> +def run(comb, opts):
>>> + print 'Checking %r' % comb
>>> + cpipe = os.pipe()
>>> + pid = os.fork()
>>> + if pid == 0:
>>> + os.close(cpipe[0])
>>> + ret = make_comb(comb, opts, cpipe[1])
>>> + sys.exit(ret)
>>> +
>>> + # Wait for the main process to get ready
>>> + os.close(cpipe[1])
>>> + res = os.read(cpipe[0], 16)
>>> + os.close(cpipe[0])
>>> +
>>> + if res == '0':
>>> + res = cr_test(pid)
>>> +
>>> + print 'Wake up test'
>>> + s = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM, 0)
>>> + if res:
>>> + res = '0'
>>> + else:
>>> + res = 'X'
>>> + try:
>>> + # Kick the test to check its state
>>> + s.sendto(res, '\0CRIUPCSK')
>>> + except:
>>> + # Restore might have failed or smth else happenned
>>> + os.kill(pid, signal.SIGKILL)
>>> + s.close()
>>> +
>>> + # Wait for the guy to exit and get the result (PASS/FAIL)
>>> + p, st = os.waitpid(pid, 0)
>>> + if os.WIFEXITED(st):
>>> + st = os.WEXITSTATUS(st)
>>> +
>>> + print 'Done (%d, pid == %d)' % (st, pid)
>>> + return st == 0
>>> +
>>> +
>>> +p = argparse.ArgumentParser("CRIU test suite")
>>> +p.add_argument("--tasks", help = "Number of tasks", default = '2')
>>> +p.add_argument("--pipes", help = "Number of pipes", default = '2')
>>> +opts = p.parse_args()
>>> +opts.tasks = int(opts.tasks)
>>> +opts.pipes = int(opts.pipes)
>>> +
>>> +pipe_combs = mix(opts.tasks, opts.pipes)
>>> +
>>> +for comb in pipe_combs:
>>> + if not run(comb, opts):
>>> + print 'FAIL'
>>> + break
>>> +else:
>>> + print 'PASS'
>>>
>> .
>>
>
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