rcu: Eliminate unused APIs intended for adaptive ticks

The rcu_user_enter_after_irq() and rcu_user_exit_after_irq()
functions were intended for use by adaptive ticks, but changes
in implementation have rendered them unnecessary.  This commit
therefore removes them.

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

1 files changed, 0 insertions, 43 deletions

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 338f1d1c1c66..8807019138c6 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -444,27 +444,6 @@ void rcu_user_enter(void)
 {
         rcu_eqs_enter(1);
 }
-
-/**
- * rcu_user_enter_after_irq - inform RCU that we are going to resume userspace
- * after the current irq returns.
- *
- * This is similar to rcu_user_enter() but in the context of a non-nesting
- * irq. After this call, RCU enters into idle mode when the interrupt
- * returns.
- */
-void rcu_user_enter_after_irq(void)
-{
-        unsigned long flags;
-        struct rcu_dynticks *rdtp;
-
-        local_irq_save(flags);
-        rdtp = &__get_cpu_var(rcu_dynticks);
-        /* Ensure this irq is interrupting a non-idle RCU state.  */
-        WARN_ON_ONCE(!(rdtp->dynticks_nesting & DYNTICK_TASK_MASK));
-        rdtp->dynticks_nesting = 1;
-        local_irq_restore(flags);
-}
 #endif /* CONFIG_RCU_USER_QS */
 
 /**
@@ -581,28 +560,6 @@ void rcu_user_exit(void)
 {
         rcu_eqs_exit(1);
 }
-
-/**
- * rcu_user_exit_after_irq - inform RCU that we won't resume to userspace
- * idle mode after the current non-nesting irq returns.
- *
- * This is similar to rcu_user_exit() but in the context of an irq.
- * This is called when the irq has interrupted a userspace RCU idle mode
- * context. When the current non-nesting interrupt returns after this call,
- * the CPU won't restore the RCU idle mode.
- */
-void rcu_user_exit_after_irq(void)
-{
-        unsigned long flags;
-        struct rcu_dynticks *rdtp;
-
-        local_irq_save(flags);
-        rdtp = &__get_cpu_var(rcu_dynticks);
-        /* Ensure we are interrupting an RCU idle mode. */
-        WARN_ON_ONCE(rdtp->dynticks_nesting & DYNTICK_TASK_NEST_MASK);
-        rdtp->dynticks_nesting += DYNTICK_TASK_EXIT_IDLE;
-        local_irq_restore(flags);
-}
 #endif /* CONFIG_RCU_USER_QS */
 
 /**