locking/lockdep: Do not record IRQ state within lockdep code
authorSteven Rostedt (VMware) <rostedt@goodmis.org>
Wed, 4 Apr 2018 18:06:30 +0000 (14:06 -0400)
committerIngo Molnar <mingo@kernel.org>
Thu, 21 Jun 2018 16:19:01 +0000 (18:19 +0200)
While debugging where things were going wrong with mapping
enabling/disabling interrupts with the lockdep state and actual real
enabling and disabling interrupts, I had to silent the IRQ
disabling/enabling in debug_check_no_locks_freed() because it was
always showing up as it was called before the splat was.

Use raw_local_irq_save/restore() for not only debug_check_no_locks_freed()
but for all internal lockdep functions, as they hide useful information
about where interrupts were used incorrectly last.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/lkml/20180404140630.3f4f4c7a@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel/locking/lockdep.c

index edcac5de7ebcdb489113800c941274d8887f9b56..5fa4d3138bf106cd87f822636652c144e846f3aa 100644 (file)
@@ -1265,11 +1265,11 @@ unsigned long lockdep_count_forward_deps(struct lock_class *class)
        this.parent = NULL;
        this.class = class;
 
-       local_irq_save(flags);
+       raw_local_irq_save(flags);
        arch_spin_lock(&lockdep_lock);
        ret = __lockdep_count_forward_deps(&this);
        arch_spin_unlock(&lockdep_lock);
-       local_irq_restore(flags);
+       raw_local_irq_restore(flags);
 
        return ret;
 }
@@ -1292,11 +1292,11 @@ unsigned long lockdep_count_backward_deps(struct lock_class *class)
        this.parent = NULL;
        this.class = class;
 
-       local_irq_save(flags);
+       raw_local_irq_save(flags);
        arch_spin_lock(&lockdep_lock);
        ret = __lockdep_count_backward_deps(&this);
        arch_spin_unlock(&lockdep_lock);
-       local_irq_restore(flags);
+       raw_local_irq_restore(flags);
 
        return ret;
 }
@@ -4411,7 +4411,7 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
        if (unlikely(!debug_locks))
                return;
 
-       local_irq_save(flags);
+       raw_local_irq_save(flags);
        for (i = 0; i < curr->lockdep_depth; i++) {
                hlock = curr->held_locks + i;
 
@@ -4422,7 +4422,7 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len)
                print_freed_lock_bug(curr, mem_from, mem_from + mem_len, hlock);
                break;
        }
-       local_irq_restore(flags);
+       raw_local_irq_restore(flags);
 }
 EXPORT_SYMBOL_GPL(debug_check_no_locks_freed);