Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU changes for v3.4 from Ingo Molnar.  The major features of this
series are:

 - making RCU more aggressive about entering dyntick-idle mode in order
   to improve energy efficiency

 - converting a few more call_rcu()s to kfree_rcu()s

 - applying a number of rcutree fixes and cleanups to rcutiny

 - removing CONFIG_SMP #ifdefs from treercu

 - allowing RCU CPU stall times to be set via sysfs

 - adding CPU-stall capability to rcutorture

 - adding more RCU-abuse diagnostics

 - updating documentation

 - fixing yet more issues located by the still-ongoing top-to-bottom
   inspection of RCU, this time with a special focus on the CPU-hotplug
   code path.

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
  rcu: Stop spurious warnings from synchronize_sched_expedited
  rcu: Hold off RCU_FAST_NO_HZ after timer posted
  rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop
  rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections
  rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()
  rcu: Remove redundant check for rcu_head misalignment
  PTR_ERR should be called before its argument is cleared.
  rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep
  rcu: Trace only after NULL-pointer check
  rcu: Call out dangers of expedited RCU primitives
  rcu: Rework detection of use of RCU by offline CPUs
  lockdep: Add CPU-idle/offline warning to lockdep-RCU splat
  rcu: No interrupt disabling for rcu_prepare_for_idle()
  rcu: Move synchronize_sched_expedited() to rcutree.c
  rcu: Check for illegal use of RCU from offlined CPUs
  rcu: Update stall-warning documentation
  rcu: Add CPU-stall capability to rcutorture
  rcu: Make documentation give more realistic rcutorture duration
  rcutorture: Permit holding off CPU-hotplug operations during boot
  rcu: Print scheduling-clock information on RCU CPU stall-warning messages
  ...

3 files changed, 5 insertions, 21 deletions

diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 86f3b88..c48adc5 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1857,11 +1857,6 @@ static int cipso_v4_genopt(unsigned char *buf, u32 buf_len,
 	return CIPSO_V4_HDR_LEN + ret_val;
 }
 
-static void opt_kfree_rcu(struct rcu_head *head)
-{
-	kfree(container_of(head, struct ip_options_rcu, rcu));
-}
-
 /**
  * cipso_v4_sock_setattr - Add a CIPSO option to a socket
  * @sk: the socket
@@ -1938,7 +1933,7 @@ int cipso_v4_sock_setattr(struct sock *sk,
 	}
 	rcu_assign_pointer(sk_inet->inet_opt, opt);
 	if (old)
-		call_rcu(&old->rcu, opt_kfree_rcu);
+		kfree_rcu(old, rcu);
 
 	return 0;
 
@@ -2005,7 +2000,7 @@ int cipso_v4_req_setattr(struct request_sock *req,
 	req_inet = inet_rsk(req);
 	opt = xchg(&req_inet->opt, opt);
 	if (opt)
-		call_rcu(&opt->rcu, opt_kfree_rcu);
+		kfree_rcu(opt, rcu);
 
 	return 0;
 
@@ -2075,7 +2070,7 @@ static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr)
 		 * remove the entire option struct */
 		*opt_ptr = NULL;
 		hdr_delta = opt->opt.optlen;
-		call_rcu(&opt->rcu, opt_kfree_rcu);
+		kfree_rcu(opt, rcu);
 	}
 
 	return hdr_delta;
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 8aa87c1..5343d9a 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -445,11 +445,6 @@ out:
 }
 
 
-static void opt_kfree_rcu(struct rcu_head *head)
-{
-	kfree(container_of(head, struct ip_options_rcu, rcu));
-}
-
 /*
  *	Socket option code for IP. This is the end of the line after any
  *	TCP,UDP etc options on an IP socket.
@@ -525,7 +520,7 @@ static int do_ip_setsockopt(struct sock *sk, int level,
 		}
 		rcu_assign_pointer(inet->inet_opt, opt);
 		if (old)
-			call_rcu(&old->rcu, opt_kfree_rcu);
+			kfree_rcu(old, rcu);
 		break;
 	}
 	case IP_PKTINFO:
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index edf167e..30420bc 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -413,12 +413,6 @@ struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data
 	return NULL;
 }
 
-static void mesh_gate_node_reclaim(struct rcu_head *rp)
-{
-	struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
-	kfree(node);
-}
-
 /**
  * mesh_path_add_gate - add the given mpath to a mesh gate to our path table
  * @mpath: gate path to add to table
@@ -479,7 +473,7 @@ static int mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
 		if (gate->mpath == mpath) {
 			spin_lock_bh(&tbl->gates_lock);
 			hlist_del_rcu(&gate->list);
-			call_rcu(&gate->rcu, mesh_gate_node_reclaim);
+			kfree_rcu(gate, rcu);
 			spin_unlock_bh(&tbl->gates_lock);
 			mpath->sdata->u.mesh.num_gates--;
 			mpath->is_gate = false;