From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Wed, 16 Mar 2016 23:32:24 +0000 (-0700)
Subject: rcu: Consolidate expedited GP code into exp_funnel_lock()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=aff12cdf86e6fa891d1c30c0fad112d138bd7b10;p=linux-beck.git

rcu: Consolidate expedited GP code into exp_funnel_lock()

This commit pulls the grace-period-start counter adjustment and tracing
from synchronize_rcu_expedited() and synchronize_sched_expedited()
into exp_funnel_lock(), thus eliminating some code duplication.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 5b1c8fd89af0..e8fff14e417b 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3653,6 +3653,8 @@ fastpath:
 		mutex_unlock(&rsp->exp_mutex);
 		return true;
 	}
+	rcu_exp_gp_seq_start(rsp);
+	trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
 	return false;
 }
 
@@ -3905,9 +3907,6 @@ void synchronize_sched_expedited(void)
 	if (exp_funnel_lock(rsp, s))
 		return;  /* Someone else did our work for us. */
 
-	rcu_exp_gp_seq_start(rsp);
-	trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
-
 	/* Initialize the rcu_node tree in preparation for the wait. */
 	sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler);
 
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 529a44085a63..ff1cd4e1188d 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -751,9 +751,6 @@ void synchronize_rcu_expedited(void)
 	if (exp_funnel_lock(rsp, s))
 		return;  /* Someone else did our work for us. */
 
-	rcu_exp_gp_seq_start(rsp);
-	trace_rcu_exp_grace_period(rsp->name, s, TPS("start"));
-
 	/* Initialize the rcu_node tree in preparation for the wait. */
 	sync_rcu_exp_select_cpus(rsp, sync_rcu_exp_handler);