cpuset: Expose cpuset.cpus.subpartitions with cgroup_debug

For debugging purpose, it will be useful to expose the content of the
subparts_cpus as a read-only file to see if the code work correctly.
However, subparts_cpus will not be used at all in most use cases. So
adding a new cpuset file that clutters the cgroup directory may not be
desirable.  This is now being done by using the hidden "cgroup_debug"
kernel command line option to expose a new "cpuset.cpus.subpartitions"
file.

That option was originally used by the debug controller to expose
itself when configured into the kernel. This is now extended to set an
internal flag used by cgroup_addrm_files(). A new CFTYPE_DEBUG flag
can now be used to specify that a cgroup file should only be created
when the "cgroup_debug" option is specified.

Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Waiman Long 2018-11-08 10:08:46 -05:00 committed by Tejun Heo
parent 90e92f2d55
commit 5cf8114d6e
5 changed files with 28 additions and 4 deletions

View file

@ -373,11 +373,9 @@ struct cgroup_subsys debug_cgrp_subsys = {
* On v2, debug is an implicit controller enabled by "cgroup_debug" boot
* parameter.
*/
static int __init enable_cgroup_debug(char *str)
void __init enable_debug_cgroup(void)
{
debug_cgrp_subsys.dfl_cftypes = debug_files;
debug_cgrp_subsys.implicit_on_dfl = true;
debug_cgrp_subsys.threaded = true;
return 1;
}
__setup("cgroup_debug", enable_cgroup_debug);