[CRIU] [PATCH v3] Add docker phaul driver

[Hui Kang]

On Wed, Oct 21, 2015 at 8:23 AM, Pavel Emelyanov <xemul at parallels.com> wrote:
>> diff --git a/phaul/p_haul_iters.py b/phaul/p_haul_iters.py
>> index b2c76e3..f8b97db 100644
>> --- a/phaul/p_haul_iters.py
>> +++ b/phaul/p_haul_iters.py
>> @@ -62,6 +62,7 @@ class phaul_iter_worker:
>>               self.fs.set_options(opts)
>>               self.__force = opts["force"]
>>               self.pre_dump = opts["pre_dump"]
>> +             self.target_host_ip = opts["to"]
>>
>>       def validate_cpu(self):
>>               logging.info("Checking CPU compatibility")
>> @@ -110,6 +111,12 @@ class phaul_iter_worker:
>>               self.fs.set_work_dir(self.img.work_dir())
>>               self.fs.start_migration()
>>
>> +             # TODO: Do not do predump for docker right now. Add page-server
>> +             #       to docker C/R API, then we can enable the pre-dump
>> +             if self.htype.get_driver_name() == "docker" :
>> +                     logging.info("Disable pre-dump for docker")
>> +                     self.pre_dump = False
>> +
>
> No if self.htype.get_driver_name() == "docker" checks should remain in
> generic code, please.

What does the "No" point to in your reply? Do you think the above code
is correct or not? Thanks.

>
>>               logging.info("Checking for Dirty Tracking")
>>               if self.pre_dump == PRE_DUMP_AUTO_DETECT:
>>                       # pre-dump auto-detection
>> @@ -194,36 +201,41 @@ class phaul_iter_worker:
>>
>>               logging.info("Final dump and restore")
>>
>> -             self.target_host.start_iter()
>> -             self.img.new_image_dir()
>> +             if self.htype.get_driver_name() == "docker" :
>> +                     # call docker dump API
>> +                     self.htype.dump()
>> +                     logging.info("Dump complete")
>
> Why do you need such rough fix? Why just setting pre_dump to false doesn't help?

Two reasons. First, this part is about the final dump. So setting
predump=False does not have effect here. Second, docker driver calls
the dump() which will call docker C/R API directly. This is different
than pid or openvz.

>
>> +             else:
>> +                     self.target_host.start_iter()
>> +                     self.img.new_image_dir()
>>
>> -             logging.info("\tIssuing dump command to service")
>> +                     logging.info("\tIssuing dump command to service")
>>
>> -             req = criu_req.make_dump_req(
>> -                     self.pid, self.htype, self.img, self.criu_connection, self.fs)
>> -             resp = self.criu_connection.send_req(req)
>> -             while True:
>> -                     if resp.type != pycriu.rpc.NOTIFY:
>> -                             raise Exception("Dump failed")
>> -
>> -                     if resp.notify.script == "post-dump":
>> -                             #
>> -                             # Dump is effectively over. Now CRIU
>> -                             # waits for us to do whatever we want
>> -                             # and keeps the tasks frozen.
>> -                             #
>> -                             break
>> +                     req = criu_req.make_dump_req(
>> +                             self.pid, self.htype, self.img, self.criu_connection, self.fs)
>> +                     resp = self.criu_connection.send_req(req)
>> +                     while True:
>> +                             if resp.type != pycriu.rpc.NOTIFY:
>> +                                     raise Exception("Dump failed")
>> +
>> +                             if resp.notify.script == "post-dump":
>> +                                     #
>> +                                     # Dump is effectively over. Now CRIU
>> +                                     # waits for us to do whatever we want
>> +                                     # and keeps the tasks frozen.
>> +                                     #
>> +                                     break
>>
>> -                     elif resp.notify.script == "network-lock":
>> -                             self.htype.net_lock()
>> -                     elif resp.notify.script == "network-unlock":
>> -                             self.htype.net_unlock()
>> +                             elif resp.notify.script == "network-lock":
>> +                                     self.htype.net_lock()
>> +                             elif resp.notify.script == "network-unlock":
>> +                                     self.htype.net_unlock()
>>
>> -                     logging.info("\t\tNotify (%s)", resp.notify.script)
>> -                     resp = self.criu_connection.ack_notify()
>> +                             logging.info("\t\tNotify (%s)", resp.notify.script)
>> +                             resp = self.criu_connection.ack_notify()
>>
>> -             logging.info("Dump complete")
>> -             self.target_host.end_iter()
>> +                     logging.info("Dump complete")
>> +                     self.target_host.end_iter()
>>
>>               #
>>               # Dump is complete -- go to target node,
>> @@ -233,8 +245,12 @@ class phaul_iter_worker:
>>
>>               logging.info("Final FS and images sync")
>>               self.fs.stop_migration()
>> -             self.img.sync_imgs_to_target(self.target_host, self.htype,
>> -                     self.connection.mem_sk)
>> +
>> +             if self.htype.get_driver_name() == "docker" :
>> +                     self.htype.send_criu_images(self.target_host_ip)
>
> The fs_haul_docker.send_criu_images() does almost the same as phaul_images.send_criu_images
> do, please, reuse the phaul_images class functionality for this.

Do you mean "sync_imgs_to_target()" in imgaes.py? If so, yes I will
change the code to re-use sync_imgs_to_target.
Thanks.

>
>> +             else:
>> +                     self.img.sync_imgs_to_target(self.target_host, self.htype,
>> +                                                  self.connection.mem_sk)
>>
>>               logging.info("Asking target host to restore")
>>               self.target_host.restore_from_images()
>
> -- Pavel
>