iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

cgroup: Add named hierarchy disabling to cgroup_no_v1 boot param

Browse Source 
It can be useful to inhibit all cgroup1 hierarchies especially during
transition and for debugging.  cgroup_no_v1 can block hierarchies with
controllers which leaves out the named hierarchies.  Expand it to
cover the named hierarchies so that "cgroup_no_v1=all,named" disables
all cgroup1 hierarchies.

Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Marcin Pawlowski <mpawlowski@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Tejun Heo 2018-12-28 10:31:07 -08:00
parent e250d91d65
commit 3fc9c12d27
2 changed files with 19 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
Documentation/admin-guide/kernel-parameters.txt
View File

@ -486,10 +486,14 @@
cut the overhead, others just disable the usage. So
only cgroup_disable=memory is actually worthy}
cgroup_no_v1= [KNL] Disable one, multiple, all cgroup controllers in v1
Format: { controller[,controller...] | "all" }
cgroup_no_v1= [KNL] Disable cgroup controllers and named hierarchies in v1
Format: { { controller | "all" | "named" }
[,{ controller | "all" | "named" }...] }
Like cgroup_disable, but only applies to cgroup v1;
the blacklisted controllers remain available in cgroup2.
"all" blacklists all controllers and "named" disables
named mounts. Specifying both "all" and "named" disables
all v1 hierarchies.
cgroup.memory= [KNL] Pass options to the cgroup memory controller.
Format: <string>

14
kernel/cgroup/cgroup-v1.c
View File

@ -27,6 +27,9 @@
/* Controllers blocked by the commandline in v1 */
static u16 cgroup_no_v1_mask;
/* disable named v1 mounts */
static bool cgroup_no_v1_named;
/*
* pidlist destructions need to be flushed on cgroup destruction. Use a
* separate workqueue as flush domain.
@ -963,6 +966,10 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
}
if (!strncmp(token, "name=", 5)) {
const char *name = token + 5;
/* blocked by boot param? */
if (cgroup_no_v1_named)
return -ENOENT;
/* Can't specify an empty name */
if (!strlen(name))
return -EINVAL;
@ -1292,7 +1299,12 @@ static int __init cgroup_no_v1(char *str)
if (!strcmp(token, "all")) {
cgroup_no_v1_mask = U16_MAX;
break;
continue;
}
if (!strcmp(token, "named")) {
cgroup_no_v1_named = true;
continue;
}
for_each_subsys(ss, i) {