rcu: Stop disabling expedited RCU CPU stall warnings

Now that RCU expedited grace periods are always driven by a workqueue,
there is no need to account for signal reception, and thus no need
to disable expedited RCU CPU stall warnings due to signal reception.
This commit therefore removes the signal-reception checks, leaving a
WARN_ON() to catch possible future bugs.

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

diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 97f5ffe..3a647eb 100644 (file)
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -427,12 +427,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
                                jiffies_stall);
                if (ret > 0 || sync_rcu_preempt_exp_done(rnp_root))
                        return;
-               if (ret < 0) {
-                       /* Hit a signal, disable CPU stall warnings. */
-                       swait_event(rsp->expedited_wq,
-                                  sync_rcu_preempt_exp_done(rnp_root));
-                       return;
-               }
+               WARN_ON(ret < 0);  /* workqueues should not be signaled. */
                pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {",
                       rsp->name);
                ndetected = 0;