rcu/srcutiny: don't return before reenabling preemption

Code after the return statement is dead. Enable preemption before
returning from srcu_drive_gp().

This will be important when/if PREEMPT_AUTO (lazy resched) gets merged.

Fixes: 65b4a59557f6 ("srcu: Make Tiny SRCU explicitly disable preemption")
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Neeraj Upadhyay <Neeraj.Upadhyay@amd.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>

diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c
index 549c03336ee97150598a37e4c39f981ad21c98d5..4dcbf8aa80ff73e9844482356c28967d13a87e24 100644 (file)
--- a/kernel/rcu/srcutiny.c
+++ b/kernel/rcu/srcutiny.c
@@ -122,8 +122,8 @@ void srcu_drive_gp(struct work_struct *wp)
        ssp = container_of(wp, struct srcu_struct, srcu_work);
        preempt_disable();  // Needed for PREEMPT_AUTO
        if (ssp->srcu_gp_running || ULONG_CMP_GE(ssp->srcu_idx, READ_ONCE(ssp->srcu_idx_max))) {
-               return; /* Already running or nothing to do. */
                preempt_enable();
+               return; /* Already running or nothing to do. */
        }
 
        /* Remove recently arrived callbacks and wait for readers. */