rcu: Clean up code based on review feedback from Josh Triplett, part 3

Whitespace fixes, updated comments, and trivial code movement.

o	Fix whitespace error in RCU_HEAD_INIT()

o	Move "So where is rcu_write_lock()" comment so that it does
	not come between the rcu_read_unlock() header comment and
	the rcu_read_unlock() definition.

o	Move the module_param statements for blimit, qhimark, and
	qlowmark to immediately follow the corresponding
	definitions.

o	In __rcu_offline_cpu(), move the assignment to rdp_me
	inside the "if" statement, given that rdp_me is not used
	outside of that "if" statement.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
LKML-Reference: <12541491931164-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 81af59b..d5597830 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -122,6 +122,10 @@
 static int qhimark = 10000;	/* If this many pending, ignore blimit. */
 static int qlowmark = 100;	/* Once only this many pending, use blimit. */
 
+module_param(blimit, int, 0);
+module_param(qhimark, int, 0);
+module_param(qlowmark, int, 0);
+
 static void force_quiescent_state(struct rcu_state *rsp, int relaxed);
 static int rcu_pending(int cpu);
 
@@ -878,8 +882,8 @@
 	 * indefinitely delay callbacks, you have far worse things to
 	 * be worrying about.
 	 */
-	rdp_me = rsp->rda[smp_processor_id()];
 	if (rdp->nxtlist != NULL) {
+		rdp_me = rsp->rda[smp_processor_id()];
 		*rdp_me->nxttail[RCU_NEXT_TAIL] = rdp->nxtlist;
 		rdp_me->nxttail[RCU_NEXT_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
 		rdp->nxtlist = NULL;
@@ -1575,7 +1579,3 @@
 }
 
 #include "rcutree_plugin.h"
-
-module_param(blimit, int, 0);
-module_param(qhimark, int, 0);
-module_param(qlowmark, int, 0);