Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - xattr support added.  The implementation is shared with tmpfs.  The
   usage is restricted and intended to be used to manage per-cgroup
   metadata by system software.  tmpfs changes are routed through this
   branch with Hugh's permission.

 - cgroup subsystem ID handling simplified.

* 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: Define CGROUP_SUBSYS_COUNT according the configuration
  cgroup: Assign subsystem IDs during compile time
  cgroup: Do not depend on a given order when populating the subsys array
  cgroup: Wrap subsystem selection macro
  cgroup: Remove CGROUP_BUILTIN_SUBSYS_COUNT
  cgroup: net_prio: Do not define task_netpioidx() when not selected
  cgroup: net_cls: Do not define task_cls_classid() when not selected
  cgroup: net_cls: Move sock_update_classid() declaration to cls_cgroup.h
  cgroup: trivial fixes for Documentation/cgroups/cgroups.txt
  xattr: mark variable as uninitialized to make both gcc and smatch happy
  fs: add missing documentation to simple_xattr functions
  cgroup: add documentation on extended attributes usage
  cgroup: rename subsys_bits to subsys_mask
  cgroup: add xattr support
  cgroup: revise how we re-populate root directory
  xattr: extract simple_xattr code from tmpfs

3 files changed, 4 insertions, 35 deletions

diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c
index c75e3f9d060f..6bc460c38e4f 100644
--- a/net/core/netprio_cgroup.c
+++ b/net/core/netprio_cgroup.c
@@ -326,9 +326,7 @@ struct cgroup_subsys net_prio_subsys = {
         .create         = cgrp_create,
         .destroy        = cgrp_destroy,
         .attach         = net_prio_attach,
-#ifdef CONFIG_NETPRIO_CGROUP
         .subsys_id      = net_prio_subsys_id,
-#endif
         .base_cftypes   = ss_files,
         .module         = THIS_MODULE
 };
@@ -366,10 +364,6 @@ static int __init init_cgroup_netprio(void)
         ret = cgroup_load_subsys(&net_prio_subsys);
         if (ret)
                 goto out;
-#ifndef CONFIG_NETPRIO_CGROUP
-        smp_wmb();
-        net_prio_subsys_id = net_prio_subsys.subsys_id;
-#endif
 
         register_netdevice_notifier(&netprio_device_notifier);
 
@@ -386,11 +380,6 @@ static void __exit exit_cgroup_netprio(void)
 
         cgroup_unload_subsys(&net_prio_subsys);
 
-#ifndef CONFIG_NETPRIO_CGROUP
-        net_prio_subsys_id = -1;
-        synchronize_rcu();
-#endif
-
         rtnl_lock();
         for_each_netdev(&init_net, dev) {
                 old = rtnl_dereference(dev->priomap);
diff --git a/net/core/sock.c b/net/core/sock.c
index a6000fbad294..341fa1c3bd69 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -326,17 +326,6 @@ int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(__sk_backlog_rcv);
 
-#if defined(CONFIG_CGROUPS)
-#if !defined(CONFIG_NET_CLS_CGROUP)
-int net_cls_subsys_id = -1;
-EXPORT_SYMBOL_GPL(net_cls_subsys_id);
-#endif
-#if !defined(CONFIG_NETPRIO_CGROUP)
-int net_prio_subsys_id = -1;
-EXPORT_SYMBOL_GPL(net_prio_subsys_id);
-#endif
-#endif
-
 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
 {
         struct timeval tv;
@@ -1224,6 +1213,7 @@ static void sk_prot_free(struct proto *prot, struct sock *sk)
 }
 
 #ifdef CONFIG_CGROUPS
+#if IS_ENABLED(CONFIG_NET_CLS_CGROUP)
 void sock_update_classid(struct sock *sk)
 {
         u32 classid;
@@ -1235,7 +1225,9 @@ void sock_update_classid(struct sock *sk)
                 sk->sk_classid = classid;
 }
 EXPORT_SYMBOL(sock_update_classid);
+#endif
 
+#if IS_ENABLED(CONFIG_NETPRIO_CGROUP)
 void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
 {
         if (in_interrupt())
@@ -1245,6 +1237,7 @@ void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
 }
 EXPORT_SYMBOL_GPL(sock_update_netprioidx);
 #endif
+#endif
 
 /**
  *      sk_alloc - All socket objects are allocated here
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
index 7743ea8d1d38..67cf90d962f4 100644
--- a/net/sched/cls_cgroup.c
+++ b/net/sched/cls_cgroup.c
@@ -77,9 +77,7 @@ struct cgroup_subsys net_cls_subsys = {
         .name           = "net_cls",
         .create         = cgrp_create,
         .destroy        = cgrp_destroy,
-#ifdef CONFIG_NET_CLS_CGROUP
         .subsys_id      = net_cls_subsys_id,
-#endif
         .base_cftypes   = ss_files,
         .module         = THIS_MODULE,
 };
@@ -283,12 +281,6 @@ static int __init init_cgroup_cls(void)
         if (ret)
                 goto out;
 
-#ifndef CONFIG_NET_CLS_CGROUP
-        /* We can't use rcu_assign_pointer because this is an int. */
-        smp_wmb();
-        net_cls_subsys_id = net_cls_subsys.subsys_id;
-#endif
-
         ret = register_tcf_proto_ops(&cls_cgroup_ops);
         if (ret)
                 cgroup_unload_subsys(&net_cls_subsys);
@@ -301,11 +293,6 @@ static void __exit exit_cgroup_cls(void)
 {
         unregister_tcf_proto_ops(&cls_cgroup_ops);
 
-#ifndef CONFIG_NET_CLS_CGROUP
-        net_cls_subsys_id = -1;
-        synchronize_rcu();
-#endif
-
         cgroup_unload_subsys(&net_cls_subsys);
 }