rcu: Remove rsp parameter from __call_rcu() and friend

There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions.  This commit therefore removes the rsp parameter from
__call_rcu_core() and __call_rcu().

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

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 6c86004..9f5e67e 100644 (file)
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2814,8 +2814,8 @@ static void invoke_rcu_core(void)
 /*
  * Handle any core-RCU processing required by a call_rcu() invocation.
  */
-static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp,
-                           struct rcu_head *head, unsigned long flags)
+static void __call_rcu_core(struct rcu_data *rdp, struct rcu_head *head,
+                           unsigned long flags)
 {
        /*
         * If called from an extended quiescent state, invoke the RCU
@@ -2847,10 +2847,10 @@ static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp,
                } else {
                        /* Give the grace period a kick. */
                        rdp->blimit = LONG_MAX;
-                       if (rsp->n_force_qs == rdp->n_force_qs_snap &&
+                       if (rcu_state.n_force_qs == rdp->n_force_qs_snap &&
                            rcu_segcblist_first_pend_cb(&rdp->cblist) != head)
                                force_quiescent_state();
-                       rdp->n_force_qs_snap = rsp->n_force_qs;
+                       rdp->n_force_qs_snap = rcu_state.n_force_qs;
                        rdp->qlen_last_fqs_check = rcu_segcblist_n_cbs(&rdp->cblist);
                }
        }
@@ -2870,11 +2870,11 @@ static void rcu_leak_callback(struct rcu_head *rhp)
  * is expected to specify a CPU.
  */
 static void
-__call_rcu(struct rcu_head *head, rcu_callback_t func,
-          struct rcu_state *rsp, int cpu, bool lazy)
+__call_rcu(struct rcu_head *head, rcu_callback_t func, int cpu, bool lazy)
 {
        unsigned long flags;
        struct rcu_data *rdp;
+       struct rcu_state __maybe_unused *rsp = &rcu_state;
 
        /* Misaligned rcu_head! */
        WARN_ON_ONCE((unsigned long)head & (sizeof(void *) - 1));
@@ -2932,7 +2932,7 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func,
                                   rcu_segcblist_n_cbs(&rdp->cblist));
 
        /* Go handle any RCU core processing required. */
-       __call_rcu_core(rsp, rdp, head, flags);
+       __call_rcu_core(rdp, head, flags);
        local_irq_restore(flags);
 }
 
@@ -2973,7 +2973,7 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func,
  */
 void call_rcu(struct rcu_head *head, rcu_callback_t func)
 {
-       __call_rcu(head, func, &rcu_state, -1, 0);
+       __call_rcu(head, func, -1, 0);
 }
 EXPORT_SYMBOL_GPL(call_rcu);
 
@@ -3000,7 +3000,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched);
 void kfree_call_rcu(struct rcu_head *head,
                    rcu_callback_t func)
 {
-       __call_rcu(head, func, &rcu_state, -1, 1);
+       __call_rcu(head, func, -1, 1);
 }
 EXPORT_SYMBOL_GPL(kfree_call_rcu);
 
@@ -3272,7 +3272,7 @@ static void _rcu_barrier(struct rcu_state *rsp)
                                smp_mb__before_atomic();
                                atomic_inc(&rsp->barrier_cpu_count);
                                __call_rcu(&rdp->barrier_head,
-                                          rcu_barrier_callback, rsp, cpu, 0);
+                                          rcu_barrier_callback, cpu, 0);
                        }
                } else if (rcu_segcblist_n_cbs(&rdp->cblist)) {
                        _rcu_barrier_trace(rsp, TPS("OnlineQ"), cpu,