context_tracking, rcu: Rename ct_dynticks_nmi_nesting() into ct_nmi_nesting()

The context_tracking.state RCU_DYNTICKS subvariable has been renamed to
RCU_WATCHING, and the 'dynticks' prefix can be dropped without losing any
meaning.
Suggested-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>

include/linux/context_tracking_state.h

@@ -87,7 +87,7 @@ static __always_inline long ct_nesting_cpu(int cpu)
 	return ct->nesting;
 }
 
-static __always_inline long ct_dynticks_nmi_nesting(void)
+static __always_inline long ct_nmi_nesting(void)
 {
 	return __this_cpu_read(context_tracking.nmi_nesting);
 }

kernel/context_tracking.c

@@ -125,7 +125,7 @@ static void noinstr ct_kernel_exit(bool user, int offset)
 {
 	struct context_tracking *ct = this_cpu_ptr(&context_tracking);
 
-	WARN_ON_ONCE(ct_dynticks_nmi_nesting() != DYNTICK_IRQ_NONIDLE);
+	WARN_ON_ONCE(ct_nmi_nesting() != DYNTICK_IRQ_NONIDLE);
 	WRITE_ONCE(ct->nmi_nesting, 0);
 	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) &&
 		     ct_nesting() == 0);
@@ -185,7 +185,7 @@ static void noinstr ct_kernel_enter(bool user, int offset)
 	trace_rcu_dyntick(TPS("End"), ct_nesting(), 1, ct_rcu_watching());
 	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) && !user && !is_idle_task(current));
 	WRITE_ONCE(ct->nesting, 1);
-	WARN_ON_ONCE(ct_dynticks_nmi_nesting());
+	WARN_ON_ONCE(ct_nmi_nesting());
 	WRITE_ONCE(ct->nmi_nesting, DYNTICK_IRQ_NONIDLE);
 	instrumentation_end();
 }
@@ -207,28 +207,28 @@ void noinstr ct_nmi_exit(void)
 
 	instrumentation_begin();
 	/*
-	 * Check for ->nmi_nesting underflow and bad ->dynticks.
+	 * Check for ->nmi_nesting underflow and bad CT state.
 	 * (We are exiting an NMI handler, so RCU better be paying attention
 	 * to us!)
 	 */
-	WARN_ON_ONCE(ct_dynticks_nmi_nesting() <= 0);
+	WARN_ON_ONCE(ct_nmi_nesting() <= 0);
 	WARN_ON_ONCE(rcu_dynticks_curr_cpu_in_eqs());
 
 	/*
 	 * If the nesting level is not 1, the CPU wasn't RCU-idle, so
 	 * leave it in non-RCU-idle state.
 	 */
-	if (ct_dynticks_nmi_nesting() != 1) {
-		trace_rcu_dyntick(TPS("--="), ct_dynticks_nmi_nesting(), ct_dynticks_nmi_nesting() - 2,
+	if (ct_nmi_nesting() != 1) {
+		trace_rcu_dyntick(TPS("--="), ct_nmi_nesting(), ct_nmi_nesting() - 2,
 				  ct_rcu_watching());
 		WRITE_ONCE(ct->nmi_nesting, /* No store tearing. */
-			   ct_dynticks_nmi_nesting() - 2);
+			   ct_nmi_nesting() - 2);
 		instrumentation_end();
 		return;
 	}
 
 	/* This NMI interrupted an RCU-idle CPU, restore RCU-idleness. */
-	trace_rcu_dyntick(TPS("Startirq"), ct_dynticks_nmi_nesting(), 0, ct_rcu_watching());
+	trace_rcu_dyntick(TPS("Startirq"), ct_nmi_nesting(), 0, ct_rcu_watching());
 	WRITE_ONCE(ct->nmi_nesting, 0); /* Avoid store tearing. */
 
 	// instrumentation for the noinstr ct_kernel_exit_state()
@@ -261,7 +261,7 @@ void noinstr ct_nmi_enter(void)
 	struct context_tracking *ct = this_cpu_ptr(&context_tracking);
 
 	/* Complain about underflow. */
-	WARN_ON_ONCE(ct_dynticks_nmi_nesting() < 0);
+	WARN_ON_ONCE(ct_nmi_nesting() < 0);
 
 	/*
 	 * If idle from RCU viewpoint, atomically increment CT state
@@ -295,11 +295,11 @@ void noinstr ct_nmi_enter(void)
 	}
 
 	trace_rcu_dyntick(incby == 1 ? TPS("Endirq") : TPS("++="),
-			  ct_dynticks_nmi_nesting(),
-			  ct_dynticks_nmi_nesting() + incby, ct_rcu_watching());
+			  ct_nmi_nesting(),
+			  ct_nmi_nesting() + incby, ct_rcu_watching());
 	instrumentation_end();
 	WRITE_ONCE(ct->nmi_nesting, /* Prevent store tearing. */
-		   ct_dynticks_nmi_nesting() + incby);
+		   ct_nmi_nesting() + incby);
 	barrier();
 }
 

kernel/rcu/tree.c

@@ -390,11 +390,11 @@ static int rcu_is_cpu_rrupt_from_idle(void)
 	/* Check for counter underflows */
 	RCU_LOCKDEP_WARN(ct_nesting() < 0,
 			 "RCU nesting counter underflow!");
-	RCU_LOCKDEP_WARN(ct_dynticks_nmi_nesting() <= 0,
+	RCU_LOCKDEP_WARN(ct_nmi_nesting() <= 0,
 			 "RCU nmi_nesting counter underflow/zero!");
 
 	/* Are we at first interrupt nesting level? */
-	nesting = ct_dynticks_nmi_nesting();
+	nesting = ct_nmi_nesting();
 	if (nesting > 1)
 		return false;
 
@@ -598,7 +598,7 @@ void rcu_irq_exit_check_preempt(void)
 
 	RCU_LOCKDEP_WARN(ct_nesting() <= 0,
 			 "RCU nesting counter underflow/zero!");
-	RCU_LOCKDEP_WARN(ct_dynticks_nmi_nesting() !=
+	RCU_LOCKDEP_WARN(ct_nmi_nesting() !=
 			 DYNTICK_IRQ_NONIDLE,
 			 "Bad RCU  nmi_nesting counter\n");
 	RCU_LOCKDEP_WARN(rcu_dynticks_curr_cpu_in_eqs(),