1 files changed, 5 insertions, 51 deletions

diff --git a/kernel/rcutiny_plugin.h b/kernel/rcutiny_plugin.h
index fc31a2d65100..918fd1e8509c 100644
--- a/kernel/rcutiny_plugin.h
+++ b/kernel/rcutiny_plugin.h
@@ -132,7 +132,6 @@ static struct rcu_preempt_ctrlblk rcu_preempt_ctrlblk = {
         RCU_TRACE(.rcb.name = "rcu_preempt")
 };
 
-static void rcu_read_unlock_special(struct task_struct *t);
 static int rcu_preempted_readers_exp(void);
 static void rcu_report_exp_done(void);
 
@@ -351,8 +350,9 @@ static int rcu_initiate_boost(void)
                         rcu_preempt_ctrlblk.boost_tasks =
                                 rcu_preempt_ctrlblk.gp_tasks;
                 invoke_rcu_callbacks();
-        } else
+        } else {
                 RCU_TRACE(rcu_initiate_boost_trace());
+        }
         return 1;
 }
 
@@ -527,23 +527,11 @@ void rcu_preempt_note_context_switch(void)
 }
 
 /*
- * Tiny-preemptible RCU implementation for rcu_read_lock().
- * Just increment ->rcu_read_lock_nesting, shared state will be updated
- * if we block.
- */
-void __rcu_read_lock(void)
-{
-        current->rcu_read_lock_nesting++;
-        barrier();  /* needed if we ever invoke rcu_read_lock in rcutiny.c */
-}
-EXPORT_SYMBOL_GPL(__rcu_read_lock);
-
-/*
  * Handle special cases during rcu_read_unlock(), such as needing to
  * notify RCU core processing or task having blocked during the RCU
  * read-side critical section.
  */
-static noinline void rcu_read_unlock_special(struct task_struct *t)
+void rcu_read_unlock_special(struct task_struct *t)
 {
         int empty;
         int empty_exp;
@@ -627,38 +615,6 @@ static noinline void rcu_read_unlock_special(struct task_struct *t)
 }
 
 /*
- * Tiny-preemptible RCU implementation for rcu_read_unlock().
- * Decrement ->rcu_read_lock_nesting.  If the result is zero (outermost
- * rcu_read_unlock()) and ->rcu_read_unlock_special is non-zero, then
- * invoke rcu_read_unlock_special() to clean up after a context switch
- * in an RCU read-side critical section and other special cases.
- */
-void __rcu_read_unlock(void)
-{
-        struct task_struct *t = current;
-
-        barrier();  /* needed if we ever invoke rcu_read_unlock in rcutiny.c */
-        if (t->rcu_read_lock_nesting != 1)
-                --t->rcu_read_lock_nesting;
-        else {
-                t->rcu_read_lock_nesting = INT_MIN;
-                barrier();  /* assign before ->rcu_read_unlock_special load */
-                if (unlikely(ACCESS_ONCE(t->rcu_read_unlock_special)))
-                        rcu_read_unlock_special(t);
-                barrier();  /* ->rcu_read_unlock_special load before assign */
-                t->rcu_read_lock_nesting = 0;
-        }
-#ifdef CONFIG_PROVE_LOCKING
-        {
-                int rrln = ACCESS_ONCE(t->rcu_read_lock_nesting);
-
-                WARN_ON_ONCE(rrln < 0 && rrln > INT_MIN / 2);
-        }
-#endif /* #ifdef CONFIG_PROVE_LOCKING */
-}
-EXPORT_SYMBOL_GPL(__rcu_read_unlock);
-
-/*
  * Check for a quiescent state from the current CPU.  When a task blocks,
  * the task is recorded in the rcu_preempt_ctrlblk structure, which is
  * checked elsewhere.  This is called from the scheduling-clock interrupt.
@@ -823,9 +779,9 @@ void synchronize_rcu_expedited(void)
                 rpcp->exp_tasks = NULL;
 
         /* Wait for tail of ->blkd_tasks list to drain. */
-        if (!rcu_preempted_readers_exp())
+        if (!rcu_preempted_readers_exp()) {
                 local_irq_restore(flags);
-        else {
+        } else {
                 rcu_initiate_boost();
                 local_irq_restore(flags);
                 wait_event(sync_rcu_preempt_exp_wq,
@@ -846,8 +802,6 @@ EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
  */
 int rcu_preempt_needs_cpu(void)
 {
-        if (!rcu_preempt_running_reader())
-                rcu_preempt_cpu_qs();
         return rcu_preempt_ctrlblk.rcb.rcucblist != NULL;
 }