We have to many controllers names in cgroup.c file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
During the dump phase, /proc/cgroups is parsed to find co-mounted cgroups.
Then, for each task /proc/self/cgroup is parsed for the cgroups that it is a
member of, and that cgroup is traversed to find any child cgroups which may
also need restoring. Any cgroups not currently mounted will be temporarily
mounted and traversed. All of this information is persisted along with the
original cg_sets, which indicate which cgroups a task is a member of.
On restore, an initial phase creates all the cgroups which were saved. Tasks
are then restored into these cgroups via cg_sets as usual.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Skip the string "name=" when recreating cgroups directories in cgyard.
For example, systemd's entries in cgroup.img are:
name: "name=systemd"
path: "/user/1000.user/4.session"
When creating systemd subdir, named= should not be part of the name.
Signed-off-by: Saied Kazemi <saied@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Otherwise cgroups sub-mounts may propagate to another namespaces
and the directory would become unremovable.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
On restore find out in which sets tasks live in and move
them there.
Optimization note -- move tasks into cgroups _before_ fork
kids to make them inherit cgroups if required. This saves
a lot of time.
Accessibility note -- when moving tasks into cgroups don't
search for existing host mounts (they may be not available)
and don't mount temporary ones (may be impossible due to
user namespaces). Instead introduce service fd with a yard
of mounts.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Each task points to a single ID of cgroup-set it lives in. This
is done so to save some space in the image, as tasks likely
live in the same set of cgroups.
Other than this we keep track of what cgroup set we dump the
subtree from. If it happens, that root task lives in the same
cgroup set as criu does, we don't allow for any other sub-cgroups
and make restore (next patch) much simpler and faster.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
