criu managed cgroups is now an opt-in thing, so by default criu does not manage
(i.e. dump or restore) cgroups. This allows users to use the previous behavior.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Andrey validly pointed out, that restoring pdeath_sig is not
compatible with criu_restore_child() call -- after criu restore
children, it will exit and fire the pdeath_sig into restored
tree root, potentially killing it.
The fix for that could be -- when started in swrk more, criu can
restore tree not as children tasks, but as siblings, using the
CLONE_PARENT flag when fork()-ing the root task.
With this we should also take care about errors handing -- right
now criu catches the SIGCHILD from dying children tasks, and
since we plan to create them be children of the criu parent (the
library caller) we will not be able to catch them. To do so we
SEIZE the root task in advance thus causing all SIGCHLD-s go to
criu, not to its parent.
Having this done we no longer need the SUBREAPER trick in the
library call -- tasks get restored right as callers kids :)
Some thoughts for future -- using this trick we can finally make
"natural" restoration of shell jobs. I.e. -- make criu restore
some subtree right under bash, w/o leaving itself as intermediate
task and w/o re-parenting the subtree to init after restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrey Vagin <avagin@parallels.com>
Perform dumping but with preliminary iterations. Each
time an iteration ends the ->more callback is called.
The callback's return value is
- positive -- one more iteration starts
- zero -- final dump is performed and call exits
- negative -- dump is aborted, the value is returned
back from criu_dump_iters
Inside callback one may (well, should) call criu_set_
function to alter the details of next iterations. In
particluar, then prev and next images directories should
be changed.
The @pi argument is an opaque value that caller may
use to request pre-dump statistics (not yet implemented).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
After a bit more thinking I found a way to fetch arguments
from notifications -- pass opaque value into callback and
provide a set of calls for exploring one.
With this we can
a) provide more data if service supplies additional fields
in the future
b) not check the action name to decide whether or not the
requested argument is available
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This is achieved by supplying the callback. Every time a notification
arrives the callback is called. Return value of 0 means continue,
any other value aborst the request and the value is reported back
to the caller (from criu_dump/criu_restore calls).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It fully uses the swrk action of criu. The problems, that caller may
have is that the restored tasks die _before_ libcriu's call returns.
v2:
* rename _sub to _child
* unblock sigchild before execl-ing criu
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The --exec-cmd option specifies a command that will be execvp()-ed on successful
restore. This way the command specified here will become the parent process of
the restored process tree.
Waiting for the restored processes to finish is responsibility of this command.
All service FDs are closed before we call execvp(). Standad output and error of
the command are redirected to the log file when we are restoring through the RPC
service.
This option will be used when restoring LinuX Containers and it seems helpful
for perf or other use cases when restored processes must be supervised by a
parent.
Two directions were researched in order to integrate CRIU and LXC:
1. We tell to CRIU, that after restoring container is should execve()
lxc properly explaining to it that there's a new container hanging
around.
2. We make LXC set himself as child subreaper, then fork() criu and ask
it to detach (-d) from restore container afterwards. Being a subreaper,
it should get the container's init into his child list after it.
The main reason for choosing the first option is that the second one can't work
with the RPC service. If we call restore via the service then criu service will
be the top-most task in the hierarchy and will not be able to reparent the
restore trees to any other task in the system. Calling execve from service
worker sub-task (and daemonizing it) should solve this.
Signed-off-by: Deyan Doychev <deyandoichev@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This function implements the --root command line option in libcriu.
Signed-off-by: Deyan Doychev <deyandoichev@gmail.com>
Reviewed-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The top-level makefile defines an ARCH_DIR variable. Always use
it rather than referencing ARCH directly, since ARCH may be set
by the user on the command line and that raw input may not be
what needs to be used internally.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
A user may have necessary linker directories specified in CFLAGS.
Make sure to include them.
Change-Id: I76c2a7bd6e34cc282bfcd5f83cc69ae7fa2c8cc2
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Using a soname makes it easy for applications to
detect if the ABI of libcriu.so has changed.
It still creates libcriu.so as before in lib. During
'make install' additional links are created:
libcriu.so -> libcriu.so.1.0
libcriu.so.1 -> libcriu.so.1.0
Signed-off-by: Adrian Reber <adrian@lisas.de>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
As we've added work_dir_fd to RPC, lets add support for it to libcriu.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
CID 1141012 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
2. fixed_size_dest: You might overrun the 108 byte fixed-size string
"addr.sun_path" by copying "service_address" without checking the
length.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
These functions are to be used to check criu, dump process and restore process.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We need ldflags-so to link libcriu with -lprotobuf-c
and rpc.pb-c.o to use RPC.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Defining it as static char is a bad idea especially
if it get included and never used -- we will get
"unused" variable error.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Add target lib to Makefile for criu library.
Created directory lib and add there Makefile and criu.c - skelettons for criu library.
Signed-off-by: Ruslan Kupreev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
