rcu: Consolidate expedited GP code into rcu_exp_wait_wake()
Currently, synchronize_rcu_expedited() and rcu_sched_expedited() have
significant duplicate code. This commit therefore consolidates some of
this code into rcu_exp_wake(), which is now renamed to rcu_exp_wait_wake()
in recognition of its added responsibilities.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 892a140..fd86eca 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3839,14 +3839,18 @@
}
/*
- * Wake up everyone who piggybacked on the just-completed expedited
+ * Wait for the current expedited grace period to complete, and then
+ * wake up everyone who piggybacked on the just-completed expedited
* grace period. Also update all the ->exp_seq_rq counters as needed
* in order to avoid counter-wrap problems.
*/
-static void rcu_exp_wake(struct rcu_state *rsp, unsigned long s)
+static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
{
struct rcu_node *rnp;
+ synchronize_sched_expedited_wait(rsp);
+ rcu_exp_gp_seq_end(rsp);
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("end"));
rcu_for_each_node_breadth_first(rsp, rnp) {
if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s)) {
spin_lock(&rnp->exp_lock);
@@ -3857,6 +3861,8 @@
}
wake_up_all(&rnp->exp_wq[(rsp->expedited_sequence >> 1) & 0x1]);
}
+ trace_rcu_exp_grace_period(rsp->name, s, TPS("endwake"));
+ mutex_unlock(&rsp->exp_mutex);
}
/**
@@ -3904,13 +3910,7 @@
sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler);
/* Wait and clean up, including waking everyone. */
- synchronize_sched_expedited_wait(rsp);
- rcu_exp_gp_seq_end(rsp);
- trace_rcu_exp_grace_period(rsp->name, s, TPS("end"));
- rcu_exp_wake(rsp, s);
-
- trace_rcu_exp_grace_period(rsp->name, s, TPS("endwake"));
- mutex_unlock(&rsp->exp_mutex);
+ rcu_exp_wait_wake(rsp, s);
}
EXPORT_SYMBOL_GPL(synchronize_sched_expedited);