Re: [libvirt] [PATCH 2/4] Add support for systemd cgroup mount

On 07/26/2013 09:48 AM, Daniel P. Berrange wrote: > From: "Daniel P. Berrange" <berrange(a)redhat.com&gt; > > Systemd uses a named cgroup mount for tracking processes. Add > it as another type of controller, albeit one which we have to > special case in a number of places. In particular we must > never create/delete directories there, nor add tasks. Essentially > the systemd mount is to be considered read-only for libvirt. > > Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com&gt; > --- > src/util/vircgroup.c | 68 +++++++++++++++++++++++++++++++++++++++------------ > src/util/vircgroup.h | 1 + > tests/vircgrouptest.c | 9 +++++++ > 3 files changed, 63 insertions(+), 15 deletions(-) > > @@ -524,13 +541,16 @@ static int virCgroupDetect(virCgroupPtr group, > return -1; > } > > - if (parent || path[0] == '/') { > - if (virCgroupCopyPlacement(group, path, parent) < 0) > - return -1; > - } else { > - if (virCgroupDetectPlacement(group, pid, path) < 0) > - return -1; This previously called only one of the two functions... > - } > + /* In some cases we can copy part of the placement info > + * based on the parent cgroup... > + */ > + if ((parent || path[0] == '/') && > + virCgroupCopyPlacement(group, path, parent) < 0) > + return -1; > + > + /* ... but use /proc/cgroups to fill in the rest */ > + if (virCgroupDetectPlacement(group, pid, path) < 0) ...now, if virCgroupCopyPlacement returns 0, it calls both functions. Is that intentional?