On Wed, Jun 18, 2008 at 6:51 PM, Li Zefan <lizf@xxxxxxxxxxxxxx> wrote: > > Signed-off-by: Li Zefan <lizf@xxxxxxxxxxxxxx> Acked-by: Paul Menage <menage@xxxxxxxxxx> Thanks. > --- > Documentation/cgroups.txt | 6 ++++++ > include/linux/cgroup.h | 2 ++ > kernel/cgroup.c | 21 ++++++++++++++++++++- > 3 files changed, 28 insertions(+), 1 deletions(-) > > diff --git a/Documentation/cgroups.txt b/Documentation/cgroups.txt > index 824fc02..8252f5b 100644 > --- a/Documentation/cgroups.txt > +++ b/Documentation/cgroups.txt > @@ -530,6 +530,12 @@ and root cgroup. Currently this will only involve movement between > the default hierarchy (which never has sub-cgroups) and a hierarchy > that is being created/destroyed (and hence has no sub-cgroups). > > +int subsys_depend(struct cgroup_subsys *ss, unsigned long subsys_bits) > + > +Called when a cgroup subsystem wants to check if some other subsystems > +are also present in the proposed hierarchy. If this method returns error, > +the mount of the cgroup filesystem will fail. > + > 4. Questions > ============ > > diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h > index e155aa7..fc99ba4 100644 > --- a/include/linux/cgroup.h > +++ b/include/linux/cgroup.h > @@ -305,6 +305,8 @@ struct cgroup_subsys { > struct cgroup *cgrp); > void (*post_clone)(struct cgroup_subsys *ss, struct cgroup *cgrp); > void (*bind)(struct cgroup_subsys *ss, struct cgroup *root); > + int (*subsys_depend)(struct cgroup_subsys *ss, > + unsigned long subsys_bits); > /* > * This routine is called with the task_lock of mm->owner held > */ > diff --git a/kernel/cgroup.c b/kernel/cgroup.c > index 15ac0e1..18e8132 100644 > --- a/kernel/cgroup.c > +++ b/kernel/cgroup.c > @@ -774,6 +774,25 @@ static int cgroup_show_options(struct seq_file *seq, struct vfsmount *vfs) > return 0; > } > > +static int check_subsys_dependency(unsigned long subsys_bits) > +{ > + int i; > + int ret; > + struct cgroup_subsys *ss; > + > + for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) { > + ss = subsys[i]; > + > + if (test_bit(i, &subsys_bits) && ss->subsys_depend) { > + ret = ss->subsys_depend(ss, subsys_bits); > + if (ret) > + return ret; > + } > + } > + > + return 0; > +} > + > struct cgroup_sb_opts { > unsigned long subsys_bits; > unsigned long flags; > @@ -834,7 +853,7 @@ static int parse_cgroupfs_options(char *data, > if (!opts->subsys_bits) > return -EINVAL; > > - return 0; > + return check_subsys_dependency(opts->subsys_bits); > } > > static int cgroup_remount(struct super_block *sb, int *flags, char *data) > -- > 1.5.4.rc3 > > _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers