rcu: Remove unneeded __rcu_process_callbacks() argument

With the advent of __this_cpu_ptr(), it is no longer necessary to pass
both the rcu_state and rcu_data structures into __rcu_process_callbacks().
This commit therefore computes the rcu_data pointer from the rcu_state
pointer within __rcu_process_callbacks() so that callers can pass in
only the pointer to the rcu_state structure.  This paves the way for
linking the rcu_state structures together and iterating over them.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index dda43d826504a6e5085db45499f14e6dd36cd184..5376a156be8abe13501b5c6e59150a2eaa95ccb2 100644 (file)
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1788,9 +1788,10 @@ unlock_fqs_ret:
  * whom the rdp belongs.
  */
 static void
-__rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
+__rcu_process_callbacks(struct rcu_state *rsp)
 {
        unsigned long flags;
+       struct rcu_data *rdp = __this_cpu_ptr(rsp->rda);
 
        WARN_ON_ONCE(rdp->beenonline == 0);
 
@@ -1827,9 +1828,8 @@ __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp)
 static void rcu_process_callbacks(struct softirq_action *unused)
 {
        trace_rcu_utilization("Start RCU core");
-       __rcu_process_callbacks(&rcu_sched_state,
-                               &__get_cpu_var(rcu_sched_data));
-       __rcu_process_callbacks(&rcu_bh_state, &__get_cpu_var(rcu_bh_data));
+       __rcu_process_callbacks(&rcu_sched_state);
+       __rcu_process_callbacks(&rcu_bh_state);
        rcu_preempt_process_callbacks();
        trace_rcu_utilization("End RCU core");
 }

diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 9cb3a68819fae81aab2a69ad34fc0b0c325fe204..5a80cdd9a0a3f35d8be14cda97e1feeaa42c666b 100644 (file)
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -687,8 +687,7 @@ static void rcu_preempt_check_callbacks(int cpu)
  */
 static void rcu_preempt_process_callbacks(void)
 {
-       __rcu_process_callbacks(&rcu_preempt_state,
-                               &__get_cpu_var(rcu_preempt_data));
+       __rcu_process_callbacks(&rcu_preempt_state);
 }
 
 #ifdef CONFIG_RCU_BOOST