We can restore task's pgid which is not equal to its pid,
only when the respective group leader is alive. To make
restore reliable we wait for all group leaders to restore
using separate restore stage.
It's better to optimize this -- each task has a pointer on
its group leader and waits for one to become such.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We restore chroot before doing this, so if we might need to
open one, we may have no access to the /proc/... paths.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This patch adds a function for removing the restorer blob. This function
never returns and the process must be trapped on the exit from the
munmap syscall.
v2: * release parasite_ctl sturcture and use the new interface of
parasite_prep_ctl
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
For the root task the clone syscall returns the pid in criu's pidns,
but for other processes the clone syscall returns PID in the restored
namespace.
The /proc/self link contains the PID value of the current process, so if
we want to determing the PID in a criu's pidns, we should use criu's
/proc.
v2: readlink() does not append a null byte to buf, so we must do that
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have generic do_pb_show() call and tons of show_foo
routines, that just call one with proper args. Compact
the code by putting the args into array and calling
the do_pb_show() in one place.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Move image object descriptors to own image-desc
file(s). This allow to reuse the code in other tools.
I had to move show declarations to cr-show.h as well.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
With this action criu will seize tasks, grab all its memory into
page-pipes, rest dirty tracker and will then release them. Writing
the memory from page-pipes would occur after tasks are unfreezed
and thus the frozen time should become reasonably small.
When pre-dump is in action, the dirty tracking is forcedly turned
off as well as tasks are resumed afterwards, not killed, by default.
This is a prerequisite for iterative migration.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
They are not documented, thus OK for now. Two options --
* one to specify where the parent images are
* one to reset dirty memory tracking
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We'll have one more "image" file generated by dump and (surprisingly)
restore commands -- the stats one. It will contain in a single pb
object all the statistics collected by dump/restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
1. Directory with images may have a "parent" symlink pointing to the
place where the previous snapshot is
2. Each pagemap will have "in_parent" bit, which means, that the
pages for this pagemap entry are not in the respective page.img
but in parent
3. New --leave-running option to use with --snapshot not to kill
tasks after snapshot
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Show only image info relevant to given pid. Also reuse
the introduced --pid argument for exec action.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
After reworkring the way pagemap is stored the backward compatibility
was not preserved for patches simplicity. Time to return it back.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently shmem generates page images in parallel
with page server and IDs may intersect. Fix this by
making page server create larger IDs.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The page server is a process, that is about to get pages over
the network and put them into pagemap- + pages- images. Right
now what it does is simply get the data and puts it into the
image files. When we have dirty set tracking in the kernel the
page server will have to collect "page changes" and properly
integrate them into images.
Running crtools with page server is like this:
dst_node# crtools page-server --port <port> -D dump/ ...
src_node# crtools dump -t <pid> --page-server --address <dst_node> --port <port> -D dump/ ...
After this images from dst_node/dump/ and src_node/dump/ should
be put into one place and tasks can be restored out of it.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Since now we drain pages out of parasite, we can invent any format for
page dumps. Let is be ... prorobuf one! :)
Another thing to keep in mind, is that we're about to use splices and
implement iterative migration, so it's better to have actual pages be
page-aligned in the image.
And -- backward compatibility. That said the new format is:
1. pagemap-... file which contains a header (currently with a ID of
the image with pages, see below) and an array of <nr_pages:vaddr>
pairs. The first value means "how many pages to take from the
file with pages (see below)" and the second -- where in the task
address space to put them. Simple.
2. pages-... file which containes only pages one by one (thus aligned
as we want).
This patch breaks backward compatibility (old images with pages wil
be restored and then crash). Need to do it before v0.5 release.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
I will have to push some sort of map of pages to dump into parasite.
For this, I need to have estimation of how much memory I'd need for
than in parasite args. These two values will help with it.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Right now when we collect list of vmas we need to know the
number of elements in it. In the future I will need to know
more, so it makes sense to create a vmas-list object for it.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
No need to walk up the directories if we need
to include protobuf file. This was always a bad
use of ability to walk the filesystem from other
headers.
Same time we don't need -I$(SRC_DIR)/protobuf/
in general makefile anymore.
[xemul: Small fixlet in head Makefile, since patch
it out-of-order]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This allows us to have a unique place where version lives
and what is more important other subsystems (such as docs
generation) may reuse version definitions.
At moment EXTRA (which corresponds kernels -rc tag) and
NAME is not yet used, but I desided to put them in place
for future needs.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When we've read all pstree-items and their ids we
can get the desired clone-flags early and avoid all
these dances with flag calculations in fork_with_pid
and company.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's no longer required to use this option -- two currently
supported cases (tasks on host and tasks in containers) can
be detected automatically. Keep this option for future.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Add --file-locks/-l option to support handling file locks, for safety,
only used for container.
Originally-signed-off-by: Zheng Gu <cengku.gu@huawei.com>
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currenly crtools supports a case when a child shared a fd table
with parent.
Here is only two interesting things.
* Service descriptors should be cloned for each process
who shared one fd table.
* One task should restore files and other tasks should sleep in this
* time.
v2: * allocate fdt_lock from shared memory
* don't wait a child, if it doesn't share fdtable
v3: * don't move ids on the pstree image
v4: * save ids in a separate image
* save fdinfo per id instead of pid
v5: fix alignment of service_fd_id
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
fdt shared data contains PID of process, which will restore file
descriptors and a futex for synchronization.
A process with mimimal pid restores file descriptors.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It is read together with pstree items for checking what kind of
resources should be shared. Core is too big for reading it in
this place.
v2: fix check_core
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
A service fd should be created, otherwise get_service_fd returns -1.
This patch removes this functionality from other subsystems and
allows to clone service descriptors.
v2: rename open_service_fd to install_service_fd
v3: two patches were merged for bisecting
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It looks like a namespace for service descriptors.
It will be used for restoring tasks with shared fd tables.
Service descriptors should be own for each process.
v2: clone_service_fd doesn't know about sub-systems like log, proc, etc
v3: Don't try to find a free name-space.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
