[tip: core/rcu] rcu: Remove unused __rcu_is_watching() function

[tip-bot2 for Paul E. McKenney]

The following commit has been merged into the core/rcu branch of tip:

Commit-ID:     7f2a53c231fe5d9522c3b695ab454203904031ac
Gitweb:        https://git.kernel.org/tip/7f2a53c231fe5d9522c3b695ab454203904031ac
Author:        Paul E. McKenney <paulmck@xxxxxxxxxx>
AuthorDate:    Mon, 17 Aug 2020 10:37:22 -07:00
Committer:     Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Mon, 24 Aug 2020 18:37:56 -07:00

rcu: Remove unused __rcu_is_watching() function

The x86/entry work removed all uses of __rcu_is_watching(), therefore
this commit removes it entirely.

Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: <x86@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
 include/linux/rcutiny.h | 1 -
 include/linux/rcutree.h | 1 -
 kernel/entry/common.c   | 2 +-
 kernel/rcu/tree.c       | 5 -----
 4 files changed, 1 insertion(+), 8 deletions(-)

diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index 5cc9637..7c1ecdb 100644
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -103,7 +103,6 @@ static inline void rcu_scheduler_starting(void) { }
 static inline void rcu_end_inkernel_boot(void) { }
 static inline bool rcu_inkernel_boot_has_ended(void) { return true; }
 static inline bool rcu_is_watching(void) { return true; }
-static inline bool __rcu_is_watching(void) { return true; }
 static inline void rcu_momentary_dyntick_idle(void) { }
 static inline void kfree_rcu_scheduler_running(void) { }
 static inline bool rcu_gp_might_be_stalled(void) { return false; }
diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index d2f4064..59eb5cd 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -64,7 +64,6 @@ extern int rcu_scheduler_active __read_mostly;
 void rcu_end_inkernel_boot(void);
 bool rcu_inkernel_boot_has_ended(void);
 bool rcu_is_watching(void);
-bool __rcu_is_watching(void);
 #ifndef CONFIG_PREEMPTION
 void rcu_all_qs(void);
 #endif
diff --git a/kernel/entry/common.c b/kernel/entry/common.c
index 9852e0d..ad794a1 100644
--- a/kernel/entry/common.c
+++ b/kernel/entry/common.c
@@ -278,7 +278,7 @@ noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs)
 	 * terminate a grace period, if and only if the timer interrupt is
 	 * not nested into another interrupt.
 	 *
-	 * Checking for __rcu_is_watching() here would prevent the nesting
+	 * Checking for rcu_is_watching() here would prevent the nesting
 	 * interrupt to invoke rcu_irq_enter(). If that nested interrupt is
 	 * the tick then rcu_flavor_sched_clock_irq() would wrongfully
 	 * assume that it is the first interupt and eventually claim
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 396abe0..2323622 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1077,11 +1077,6 @@ static void rcu_disable_urgency_upon_qs(struct rcu_data *rdp)
 	}
 }
 
-noinstr bool __rcu_is_watching(void)
-{
-	return !rcu_dynticks_curr_cpu_in_eqs();
-}
-
 /**
  * rcu_is_watching - see if RCU thinks that the current CPU is not idle
  *