cgroup: remove cgroup_subsys argument from callbacks

The argument is not used at all, and it's not necessary, because
a specific callback handler of course knows which subsys it
belongs to.

Now only ->pupulate() takes this argument, because the handlers of
this callback always call cgroup_add_file()/cgroup_add_files().

So we reduce a few lines of code, though the shrinking of object size
is minimal.

 16 files changed, 113 insertions(+), 162 deletions(-)

   text    data     bss     dec     hex filename
5486240  656987 7039960 13183187         c928d3 vmlinux.o.orig
5486170  656987 7039960 13183117         c9288d vmlinux.o

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

4 files changed, 12 insertions, 16 deletions

diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index 3a9fd48..22036ab 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -23,9 +23,8 @@
 #include <net/sock.h>
 #include <net/netprio_cgroup.h>
 
-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 struct cgroup_subsys_state *cgrp_create(struct cgroup *cgrp);
+static void cgrp_destroy(struct cgroup *cgrp);
 static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp);
 
 struct cgroup_subsys net_prio_subsys = {
@@ -120,8 +119,7 @@ static void update_netdev_tables(void)
 	rtnl_unlock();
 }
 
-static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss,
-						 struct cgroup *cgrp)
+static struct cgroup_subsys_state *cgrp_create(struct cgroup *cgrp)
 {
 	struct cgroup_netprio_state *cs;
 	int ret;
@@ -145,7 +143,7 @@ static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss,
 	return &cs->css;
 }
 
-static void cgrp_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
+static void cgrp_destroy(struct cgroup *cgrp)
 {
 	struct cgroup_netprio_state *cs;
 	struct net_device *dev;
diff --git a/net/core/sock.c b/net/core/sock.c
index 5c5af998..688037cb 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -160,19 +160,19 @@ int mem_cgroup_sockets_init(struct cgroup *cgrp, struct cgroup_subsys *ss)
 out:
 	list_for_each_entry_continue_reverse(proto, &proto_list, node)
 		if (proto->destroy_cgroup)
-			proto->destroy_cgroup(cgrp, ss);
+			proto->destroy_cgroup(cgrp);
 	mutex_unlock(&proto_list_mutex);
 	return ret;
 }
 
-void mem_cgroup_sockets_destroy(struct cgroup *cgrp, struct cgroup_subsys *ss)
+void mem_cgroup_sockets_destroy(struct cgroup *cgrp)
 {
 	struct proto *proto;
 
 	mutex_lock(&proto_list_mutex);
 	list_for_each_entry_reverse(proto, &proto_list, node)
 		if (proto->destroy_cgroup)
-			proto->destroy_cgroup(cgrp, ss);
+			proto->destroy_cgroup(cgrp);
 	mutex_unlock(&proto_list_mutex);
 }
 #endif
diff --git a/net/ipv4/tcp_memcontrol.c b/net/ipv4/tcp_memcontrol.c
index 4997878..e714c68 100644
--- a/net/ipv4/tcp_memcontrol.c
+++ b/net/ipv4/tcp_memcontrol.c
@@ -94,7 +94,7 @@ create_files:
 }
 EXPORT_SYMBOL(tcp_init_cgroup);
 
-void tcp_destroy_cgroup(struct cgroup *cgrp, struct cgroup_subsys *ss)
+void tcp_destroy_cgroup(struct cgroup *cgrp)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
 	struct cg_proto *cg_proto;
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
index f84fdc3..1afaa28 100644
--- a/net/sched/cls_cgroup.c
+++ b/net/sched/cls_cgroup.c
@@ -22,9 +22,8 @@
 #include <net/sock.h>
 #include <net/cls_cgroup.h>
 
-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 struct cgroup_subsys_state *cgrp_create(struct cgroup *cgrp);
+static void cgrp_destroy(struct cgroup *cgrp);
 static int cgrp_populate(struct cgroup_subsys *ss, struct cgroup *cgrp);
 
 struct cgroup_subsys net_cls_subsys = {
@@ -51,8 +50,7 @@ static inline struct cgroup_cls_state *task_cls_state(struct task_struct *p)
 			    struct cgroup_cls_state, css);
 }
 
-static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss,
-						 struct cgroup *cgrp)
+static struct cgroup_subsys_state *cgrp_create(struct cgroup *cgrp)
 {
 	struct cgroup_cls_state *cs;
 
@@ -66,7 +64,7 @@ static struct cgroup_subsys_state *cgrp_create(struct cgroup_subsys *ss,
 	return &cs->css;
 }
 
-static void cgrp_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
+static void cgrp_destroy(struct cgroup *cgrp)
 {
 	kfree(cgrp_cls_state(cgrp));
 }