task: Add write_signal_queues stub

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Add debug output for task_read_aux_pos

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Add some more debug output in show_task_cont

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Add task states constants

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Encode criu task states

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Show task state in debug output

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Make sure the tasks is in known state

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Encode task state with helper

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Rework internal representation

This is a huge rework to make tasks look like
ones represented in the linux kernel (internal
structure). Thus we can use same named helpers
for walking over tasks.

Another benefit is that now process tree takes
into account threads, which were missed before
this commit.

Also we start accounting zombie tasks and don't
fail on conversion if one of them are faced.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Add conversion of threads

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
task: Thread cores have no TaskCoreEntry

Thus zap core.tc, otherwise criu complains
on optional fields present in thread core.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>