When an image of a certian type is not found, CRIU sometimes
fails, sometimes ignores this fact. I propose to ignore this
fact always and treat absent images and those containing no
objects inside (i.e. -- empty). If the latter code flow will
_need_ objects, then criu will fail later.
Why object will be explicitly required? For example, due to
restoring code reading the image with pb_read_one, w/o the
_eof suffix thus required the object to be in the image.
Another example is objects dependencies. E.g. fdinfo objects
require various files objects. So missing image files will
result in non-resolved searches later.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
and return an error, if a proccess live in another userns,
because criu doesn't support it.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When creating helpers, we need to make sure their
PIDs do not intersect with threads' IDs.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We want to have buffered images to speed up dump and,
slightly, restore. Right now we use plan file descriptors
to write and read images to/from. Making them buffered
cannot be gracefully done on plain fds, so introduce
a new class.
This will also help if (when?) we will want to do more
complex changes with images, e.g. store them all in one
file or send them directly to the network.
For now the cr_img just contains one int _fd variable.
This patch chages the prototype of open_image() to
return struct cr_img *, pb_(read|write)* to accept one
and fixes the compilation of the rest of the code :)
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
The same -- int-fd will soon go away, so return the
explicit int -1 instead of it.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
They don't change these objects, so can share them
with parent (will be created slightly faster :) ).
The plan is to make them CLONE_VM, but it's not that
easy.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We explicitly setns() every single task by hands when restoring
mount namespaces, they can be created without the NEWNS flag.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrey Vagin <avagin@parallels.com>
Now we supports sub-mntns, so root_ns_mask sounds more correct than
current_ns_mask.
v2: typo fix
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
v2: another attempt to write readable code:)
v3: clean up
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently ns_ids list is filled only on dump. Soon we'll need this
list for mount namespaces on restore, e.g. to know which tasks share
the namespaces.
v2: merge the patch "namespace: add a function to search an ns_id
item by id" into this one.
v3: add prefix rst_ to add_ns_id
v4: look up namespace by two values -- type AND ID
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This as well gives us minus one image per-task and
allocates more space on core task entry.
One thing to note -- the amount of posix timers is
not easily accessible at the core entry allocation
time, so the respective array is allocated on demand.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This allows to have one image less per-task, which in turn
reduces live migration time a little bit.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This one will hold all info about timers in the core_entry.
Since timers are always per-task, this one is on task core
entry.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
On PI machine we've got
| CC protobuf.o
| pstree.c: In function ‘core_entry_alloc’:
| pstree.c:36:10: error: ‘RLIM_NLIMITS’ undeclared (first use in this function)
due to old kernel headers. Note I've dropped off
BUG_ON here to localize all things in pstree code,
no need to sprinkle constants.
Reported-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
On Thu, Mar 13, 2014 at 04:20:37PM +0400, Pavel Emelyanov wrote:
>
> Would you rework this patch on top of my recent
> "allocate Core in on xmalloc call" one?
Attached.
>From c2233d4fafce30c4e7214a1a7ab3677824a30d75 Mon Sep 17 00:00:00 2001
From: Cyrill Gorcunov <gorcunov@openvz.org>
Date: Thu, 13 Mar 2014 16:57:14 +0400
Subject: [PATCH] rlimit: Allocate and free appropriate Core entry
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Right now we do it two times -- on shmem prepare and
on the restore itself. Make collection only once as
we do for fdinfo-s -- root task reads all stuff in and
populates tasks' rst_info with it.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
restorer.h includes about 20 headers. Any changes in these headers
provoke to recompilation of pstree.c.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
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>
A pstree item will contain pid and state. Both these properties will be
determined after creating processes and will be used from the
controlling proces.
v2: fix the error path
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's not arch dependent by any means, thus it looks
strange that we allocate it in arch/ but free in
pstree.c.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have three arrays for thread related data: item->threads,
parasite_ctl->thread and tid_state in parasite.
With this patch a thread will have the same index in all arrays.
The zero index is used for a thread leader.
In this case we don't need to search thread_state in parasite.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When parasite daemon mode will be implemented we get deprived of ability
to fetch registers at the late moment of dumping as we were, thus just
bind CoreEntry to pstree item and allocate CoreEntry'ies for every
thread found, once process tree is in seized state.
Then immediately fill CoreEntry'ies with registers. We use prctl
opcode for that but fetch a complete set of registers including
FPU state, and convert them into protobuf format.
Zombie tasks remains untouched, we allocate CoreEntry for them
right at moment of dumping becuase we don't need registers there
to be written on disk.
This way get_task_regs no longer need parasite_ctl argument
and it's zapped.
Still parasite_ctl has own copy of general registers set but
this is because we need them to be in cpu native format unlike
ones kept in CoreEntry.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
pstree.c:273:3: warning: Value stored to 'ret' is never read
ret = 0;
^ ~
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The root task must remain a session leader after c/r. The root task
can be executed in another pidns and the sid from another name space
will be invalid.
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Reported-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Otherwise we will get nil dereference in shared_fdt_prepare
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Here is updated one.
0001-ids-Make-sure-kIDs-is-present-in-image.patch
>From dee67b483f0ed1a6f81ebe95ae9bdf74d3ab2ad7 Mon Sep 17 00:00:00 2001
From: Cyrill Gorcunov <gorcunov@openvz.org>
Date: Fri, 15 Mar 2013 00:43:30 +0400
Subject: [PATCH 1/2] ids: Make sure kIDs is present in image
Otherwise yield error instead of nil dereference
if we meet a broken image.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This facrots out common core members freeing into pstree.c
helper. Per-arch freeing helpers are now symmetrical to the
allocating ones.
This is a merge of two Cyrill's patches.
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>
Helpers don't have any IDs on board and thus checks for "is
my X shared with parent" will be wrong.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Introduce the current_ns_mask variable, that collects info about
which namespaces tasks being dumped and to be restored live in.
For simlicity all tasks are supposed to live in one set of spaces.
This should be fixed eventually.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Sometimes, when we parse some global info files, we can only care about
tasks which are taken into dump(such as file locks), which means their
pids are in the pstree.
So a function like this would be help.
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>
