rcu: Remove rcu_is_idle_cpu()

The commit 3fcd6a230fa7 ("x86/cpu: Avoid cpuinfo-induced IPIing of
idle CPUs") introduced rcu_is_idle_cpu() in order to identify the
current CPU idle state.  But commit f3eca381bd49 ("x86/aperfmperf:
Replace arch_freq_get_on_cpu()") switched to using MAX_SAMPLE_AGE,
so rcu_is_idle_cpu() is no longer used.  This commit therefore removes it.

Fixes: f3eca381bd49 ("x86/aperfmperf: Replace arch_freq_get_on_cpu()")
Signed-off-by: Yipeng Zou <zouyipeng@huawei.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index 9bc025aa79a30cbd8b99c8c6519a877ad67210cc..5c271bf3a1e7e3719c6bac630552081ddfb97a80 100644 (file)
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -146,8 +146,6 @@ static inline void rcu_virt_note_context_switch(void) { }
 static inline void rcu_cpu_stall_reset(void) { }
 static inline int rcu_jiffies_till_stall_check(void) { return 21 * HZ; }
 static inline void rcu_irq_exit_check_preempt(void) { }
-#define rcu_is_idle_cpu(cpu) \
-       (is_idle_task(current) && !in_nmi() && !in_hardirq() && !in_serving_softirq())
 static inline void exit_rcu(void) { }
 static inline bool rcu_preempt_need_deferred_qs(struct task_struct *t)
 {

diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 70795386b9ffac665d9319ae610a857ae24b3c67..4003bf6cfa1c275c6a5abe6cf25a5bda89d884f1 100644 (file)
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -87,8 +87,6 @@ bool poll_state_synchronize_rcu_full(struct rcu_gp_oldstate *rgosp);
 void cond_synchronize_rcu(unsigned long oldstate);
 void cond_synchronize_rcu_full(struct rcu_gp_oldstate *rgosp);
 
-bool rcu_is_idle_cpu(int cpu);
-
 #ifdef CONFIG_PROVE_RCU
 void rcu_irq_exit_check_preempt(void);
 #else

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 5ec97e3f7468fe090f2f2d6e5495962d7353e4c5..f6561aa401c04f0f0bd75c9a5618f7d551b48723 100644 (file)
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -301,12 +301,6 @@ static bool rcu_dynticks_in_eqs(int snap)
        return !(snap & RCU_DYNTICKS_IDX);
 }
 
-/* Return true if the specified CPU is currently idle from an RCU viewpoint.  */
-bool rcu_is_idle_cpu(int cpu)
-{
-       return rcu_dynticks_in_eqs(rcu_dynticks_snap(cpu));
-}
-
 /*
  * Return true if the CPU corresponding to the specified rcu_data
  * structure has spent some time in an extended quiescent state since