lockdep: Fix -Wunused-parameter for _THIS_IP_

While looking into a bug related to the compiler's handling of addresses
of labels, I noticed some uses of _THIS_IP_ seemed unused in lockdep.
Drive by cleanup.

-Wunused-parameter:
kernel/locking/lockdep.c:1383:22: warning: unused parameter 'ip'
kernel/locking/lockdep.c:4246:48: warning: unused parameter 'ip'
kernel/locking/lockdep.c:4844:19: warning: unused parameter 'ip'

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lore.kernel.org/r/20220314221909.2027027-1-ndesaulniers@google.com

Author: nickdesaulniers

arch/arm64/kernel/entry-common.c

@@ -75,7 +75,7 @@ static __always_inline void __exit_to_kernel_mode(struct pt_regs *regs)
 	if (interrupts_enabled(regs)) {
 		if (regs->exit_rcu) {
 			trace_hardirqs_on_prepare();
-			lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+			lockdep_hardirqs_on_prepare();
 			rcu_irq_exit();
 			lockdep_hardirqs_on(CALLER_ADDR0);
 			return;
@@ -121,7 +121,7 @@ static __always_inline void enter_from_user_mode(struct pt_regs *regs)
 static __always_inline void __exit_to_user_mode(void)
 {
 	trace_hardirqs_on_prepare();
-	lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+	lockdep_hardirqs_on_prepare();
 	user_enter_irqoff();
 	lockdep_hardirqs_on(CALLER_ADDR0);
 }
@@ -179,7 +179,7 @@ static void noinstr arm64_exit_nmi(struct pt_regs *regs)
 	ftrace_nmi_exit();
 	if (restore) {
 		trace_hardirqs_on_prepare();
-		lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+		lockdep_hardirqs_on_prepare();
 	}
 
 	rcu_nmi_exit();
@@ -215,7 +215,7 @@ static void noinstr arm64_exit_el1_dbg(struct pt_regs *regs)
 
 	if (restore) {
 		trace_hardirqs_on_prepare();
-		lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+		lockdep_hardirqs_on_prepare();
 	}
 
 	rcu_nmi_exit();

include/linux/irqflags.h

@@ -20,13 +20,13 @@
 #ifdef CONFIG_PROVE_LOCKING
   extern void lockdep_softirqs_on(unsigned long ip);
   extern void lockdep_softirqs_off(unsigned long ip);
-  extern void lockdep_hardirqs_on_prepare(unsigned long ip);
+  extern void lockdep_hardirqs_on_prepare(void);
   extern void lockdep_hardirqs_on(unsigned long ip);
   extern void lockdep_hardirqs_off(unsigned long ip);
 #else
   static inline void lockdep_softirqs_on(unsigned long ip) { }
   static inline void lockdep_softirqs_off(unsigned long ip) { }
-  static inline void lockdep_hardirqs_on_prepare(unsigned long ip) { }
+  static inline void lockdep_hardirqs_on_prepare(void) { }
   static inline void lockdep_hardirqs_on(unsigned long ip) { }
   static inline void lockdep_hardirqs_off(unsigned long ip) { }
 #endif

include/linux/kvm_host.h

@@ -450,7 +450,7 @@ static __always_inline void guest_state_enter_irqoff(void)
 {
 	instrumentation_begin();
 	trace_hardirqs_on_prepare();
-	lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+	lockdep_hardirqs_on_prepare();
 	instrumentation_end();
 
 	guest_context_enter_irqoff();

kernel/entry/common.c

@@ -126,7 +126,7 @@ static __always_inline void __exit_to_user_mode(void)
 {
 	instrumentation_begin();
 	trace_hardirqs_on_prepare();
-	lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+	lockdep_hardirqs_on_prepare();
 	instrumentation_end();
 
 	user_enter_irqoff();
@@ -416,7 +416,7 @@ noinstr void irqentry_exit(struct pt_regs *regs, irqentry_state_t state)
 			instrumentation_begin();
 			/* Tell the tracer that IRET will enable interrupts */
 			trace_hardirqs_on_prepare();
-			lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+			lockdep_hardirqs_on_prepare();
 			instrumentation_end();
 			rcu_irq_exit();
 			lockdep_hardirqs_on(CALLER_ADDR0);
@@ -465,7 +465,7 @@ void noinstr irqentry_nmi_exit(struct pt_regs *regs, irqentry_state_t irq_state)
 	ftrace_nmi_exit();
 	if (irq_state.lockdep) {
 		trace_hardirqs_on_prepare();
-		lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+		lockdep_hardirqs_on_prepare();
 	}
 	instrumentation_end();
 

kernel/locking/lockdep.c

@@ -1380,7 +1380,7 @@ static struct lock_list *alloc_list_entry(void)
  */
 static int add_lock_to_list(struct lock_class *this,
 			    struct lock_class *links_to, struct list_head *head,
-			    unsigned long ip, u16 distance, u8 dep,
+			    u16 distance, u8 dep,
 			    const struct lock_trace *trace)
 {
 	struct lock_list *entry;
@@ -3133,19 +3133,15 @@ check_prev_add(struct task_struct *curr, struct held_lock *prev,
 	 * to the previous lock's dependency list:
 	 */
 	ret = add_lock_to_list(hlock_class(next), hlock_class(prev),
-			       &hlock_class(prev)->locks_after,
-			       next->acquire_ip, distance,
-			       calc_dep(prev, next),
-			       *trace);
+			       &hlock_class(prev)->locks_after, distance,
+			       calc_dep(prev, next), *trace);
 
 	if (!ret)
 		return 0;
 
 	ret = add_lock_to_list(hlock_class(prev), hlock_class(next),
-			       &hlock_class(next)->locks_before,
-			       next->acquire_ip, distance,
-			       calc_depb(prev, next),
-			       *trace);
+			       &hlock_class(next)->locks_before, distance,
+			       calc_depb(prev, next), *trace);
 	if (!ret)
 		return 0;
 
@@ -4236,14 +4232,13 @@ static void __trace_hardirqs_on_caller(void)
 
 /**
  * lockdep_hardirqs_on_prepare - Prepare for enabling interrupts
- * @ip:		Caller address
  *
  * Invoked before a possible transition to RCU idle from exit to user or
  * guest mode. This ensures that all RCU operations are done before RCU
  * stops watching. After the RCU transition lockdep_hardirqs_on() has to be
  * invoked to set the final state.
  */
-void lockdep_hardirqs_on_prepare(unsigned long ip)
+void lockdep_hardirqs_on_prepare(void)
 {
 	if (unlikely(!debug_locks))
 		return;
@@ -4840,8 +4835,7 @@ EXPORT_SYMBOL_GPL(__lockdep_no_validate__);
 
 static void
 print_lock_nested_lock_not_held(struct task_struct *curr,
-				struct held_lock *hlock,
-				unsigned long ip)
+				struct held_lock *hlock)
 {
 	if (!debug_locks_off())
 		return;
@@ -5017,7 +5011,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 	chain_key = iterate_chain_key(chain_key, hlock_id(hlock));
 
 	if (nest_lock && !__lock_is_held(nest_lock, -1)) {
-		print_lock_nested_lock_not_held(curr, hlock, ip);
+		print_lock_nested_lock_not_held(curr, hlock);
 		return 0;
 	}
 

kernel/sched/idle.c

@@ -102,7 +102,7 @@ void __cpuidle default_idle_call(void)
 		 * last -- this is very similar to the entry code.
 		 */
 		trace_hardirqs_on_prepare();
-		lockdep_hardirqs_on_prepare(_THIS_IP_);
+		lockdep_hardirqs_on_prepare();
 		rcu_idle_enter();
 		lockdep_hardirqs_on(_THIS_IP_);
 

kernel/trace/trace_preemptirq.c

@@ -46,7 +46,7 @@ void trace_hardirqs_on(void)
 		this_cpu_write(tracing_irq_cpu, 0);
 	}
 
-	lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+	lockdep_hardirqs_on_prepare();
 	lockdep_hardirqs_on(CALLER_ADDR0);
 }
 EXPORT_SYMBOL(trace_hardirqs_on);
@@ -94,7 +94,7 @@ __visible void trace_hardirqs_on_caller(unsigned long caller_addr)
 		this_cpu_write(tracing_irq_cpu, 0);
 	}
 
-	lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+	lockdep_hardirqs_on_prepare();
 	lockdep_hardirqs_on(CALLER_ADDR0);
 }
 EXPORT_SYMBOL(trace_hardirqs_on_caller);