cgroups: net_cls as module
Allows the net_cls cgroup subsystem to be compiled as a module
This patch modifies net/sched/cls_cgroup.c to allow the net_cls subsystem
to be optionally compiled as a module instead of builtin. The
cgroup_subsys struct is moved around a bit to allow the subsys_id to be
either declared as a compile-time constant by the cgroup_subsys.h include
in cgroup.h, or, if it's a module, initialized within the struct by
cgroup_load_subsys.
Signed-off-by: Ben Blum <bblum@andrew.cmu.edu>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
index e4877ca..7f27d2c 100644
--- a/net/sched/cls_cgroup.c
+++ b/net/sched/cls_cgroup.c
@@ -24,6 +24,25 @@
u32 classid;
};
+static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss,
+ struct cgroup *cgrp);
+static void cgrp_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp);
+static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp);
+
+struct cgroup_subsys net_cls_subsys = {
+ .name = "net_cls",
+ .create = cgrp_create,
+ .destroy = cgrp_destroy,
+ .populate = cgrp_populate,
+#ifdef CONFIG_NET_CLS_CGROUP
+ .subsys_id = net_cls_subsys_id,
+#else
+#define net_cls_subsys_id net_cls_subsys.subsys_id
+#endif
+ .module = THIS_MODULE,
+};
+
+
static inline struct cgroup_cls_state *cgrp_cls_state(struct cgroup *cgrp)
{
return container_of(cgroup_subsys_state(cgrp, net_cls_subsys_id),
@@ -79,14 +98,6 @@
return cgroup_add_files(cgrp, ss, ss_files, ARRAY_SIZE(ss_files));
}
-struct cgroup_subsys net_cls_subsys = {
- .name = "net_cls",
- .create = cgrp_create,
- .destroy = cgrp_destroy,
- .populate = cgrp_populate,
- .subsys_id = net_cls_subsys_id,
-};
-
struct cls_cgroup_head
{
u32 handle;
@@ -277,12 +288,19 @@
static int __init init_cgroup_cls(void)
{
- return register_tcf_proto_ops(&cls_cgroup_ops);
+ int ret = register_tcf_proto_ops(&cls_cgroup_ops);
+ if (ret)
+ return ret;
+ ret = cgroup_load_subsys(&net_cls_subsys);
+ if (ret)
+ unregister_tcf_proto_ops(&cls_cgroup_ops);
+ return ret;
}
static void __exit exit_cgroup_cls(void)
{
unregister_tcf_proto_ops(&cls_cgroup_ops);
+ cgroup_unload_subsys(&net_cls_subsys);
}
module_init(init_cgroup_cls);