[CRIU] [PATCH v3 4/6] p.haul: add option to enable/disable pre-dumps

[Nikita Spiridonov]

Acked-by: Nikita Spiridonov <nspiridonov at odin.com>

Acked, but it would be great to simplify --pre-dump/no-pre-dump logic in
further commits - e.g. repalce 0, 1 and 2 numbers with symbolic
constants, move 'pre_dump' flag setting in
phaul_iter_worker.start_migration to separate method and so on.

On Thu, 2015-10-08 at 14:06 +0000, Adrian Reber wrote:
> From: Adrian Reber <areber at redhat.com>
> 
> Although p.haul can now auto-detect if the used criu supports
> memory tracking this adds a command-line option to force
> pre-dumping on or off:
> 
>   --no-pre-dump        Force disable pre-dumps
>   --pre-dump           Force enable pre-dumps
> 
> Signed-off-by: Adrian Reber <areber at redhat.com>
> ---
>  p.haul                | 12 ++++++++++++
>  phaul/p_haul_iters.py | 18 ++++++++++++++----
>  2 files changed, 26 insertions(+), 4 deletions(-)
> 
> diff --git a/p.haul b/p.haul
> index e807c8f..6239709 100755
> --- a/p.haul
> +++ b/p.haul
> @@ -36,6 +36,18 @@ parser.add_argument("--log-file", help="Write logging messages to specified file
>  parser.add_argument("-j", "--shell-job",help ="Allow migration of shell jobs",
>  		    default=False, action='store_true')
>  
> +
> +parser.add_argument('--no-pre-dump', dest='pre_dump', action='store_const',
> +		    const=1, help='Force disable pre-dumps')
> +parser.add_argument('--pre-dump', dest='pre_dump', action='store_const',
> +		    const=2, help='Force enable pre-dumps')
> +
> +# If pre_dump is 0 then pre-dump autodetection should be used.
> +# If it is 1 or 2 it should be either enabled or disabled no
> +# matter if the kernel supports dirty page tracking or not.
> +
> +parser.set_defaults(pre_dump = 0)
> +
>  args = parser.parse_args()
>  
>  # Configure logging
> diff --git a/phaul/p_haul_iters.py b/phaul/p_haul_iters.py
> index ba96de3..96458b8 100644
> --- a/phaul/p_haul_iters.py
> +++ b/phaul/p_haul_iters.py
> @@ -42,6 +42,9 @@ class phaul_iter_worker:
>  		self.pid = self.htype.root_task_pid()
>  		self.fs.set_target_host(host[0])
>  
> +		# pre_dump 0 means auto-detection
> +		self.pre_dump = 0
> +
>  		logging.info("Setting up remote")
>  		self.target_host.setup(p_type)
>  
> @@ -55,6 +58,7 @@ class phaul_iter_worker:
>  		self.img.set_options(opts)
>  		self.htype.set_options(opts)
>  		self.__force = opts["force"]
> +		self.pre_dump = opts["pre_dump"]
>  
>  	def validate_cpu(self):
>  		logging.info("Checking CPU compatibility")
> @@ -87,11 +91,17 @@ class phaul_iter_worker:
>  		self.fs.set_work_dir(self.img.work_dir())
>  		self.fs.start_migration()
>  
> -		logging.info("Checking for Dirty Tracking")
> -		req = criu_req.make_dirty_tracking_req(self.htype, self.img)
> -		resp = self.criu_connection.send_req(req)
> +		if self.pre_dump == 0:
> +			# pre-dump auto-detection
> +			logging.info("Checking for Dirty Tracking")
> +			req = criu_req.make_dirty_tracking_req(self.htype, self.img)
> +			resp = self.criu_connection.send_req(req)
> +			pre_dump = resp.success
> +		elif self.pre_dump == 1:
> +			pre_dump = False
> +		else:
> +			pre_dump = True
>  
> -		pre_dump = False
>  		if resp.success:
>  			if resp.HasField('features'):
>  				if resp.features.HasField('mem_track'):