locking, percpu counters: introduce separate lock classes

Impact: fix lockdep false positives

Classify percpu_counter instances similar to regular lock objects --
that is, per instantiation site.

The networking code has increased its use of percpu_counters, which
leads to false positives if they are treated as a single class.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra
2008-12-26 15:08:55 +01:00
committed by Ingo Molnar
parent 00ef9f7348
commit ea319518ba
4 changed files with 18 additions and 22 deletions

View File

@@ -71,11 +71,11 @@ s64 __percpu_counter_sum(struct percpu_counter *fbc)
}
EXPORT_SYMBOL(__percpu_counter_sum);
static struct lock_class_key percpu_counter_irqsafe;
int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
int __percpu_counter_init(struct percpu_counter *fbc, s64 amount,
struct lock_class_key *key)
{
spin_lock_init(&fbc->lock);
lockdep_set_class(&fbc->lock, key);
fbc->count = amount;
fbc->counters = alloc_percpu(s32);
if (!fbc->counters)
@@ -87,17 +87,7 @@ int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
#endif
return 0;
}
EXPORT_SYMBOL(percpu_counter_init);
int percpu_counter_init_irq(struct percpu_counter *fbc, s64 amount)
{
int err;
err = percpu_counter_init(fbc, amount);
if (!err)
lockdep_set_class(&fbc->lock, &percpu_counter_irqsafe);
return err;
}
EXPORT_SYMBOL(__percpu_counter_init);
void percpu_counter_destroy(struct percpu_counter *fbc)
{

View File

@@ -83,11 +83,11 @@ int prop_descriptor_init(struct prop_descriptor *pd, int shift)
pd->index = 0;
pd->pg[0].shift = shift;
mutex_init(&pd->mutex);
err = percpu_counter_init_irq(&pd->pg[0].events, 0);
err = percpu_counter_init(&pd->pg[0].events, 0);
if (err)
goto out;
err = percpu_counter_init_irq(&pd->pg[1].events, 0);
err = percpu_counter_init(&pd->pg[1].events, 0);
if (err)
percpu_counter_destroy(&pd->pg[0].events);
@@ -191,7 +191,7 @@ int prop_local_init_percpu(struct prop_local_percpu *pl)
spin_lock_init(&pl->lock);
pl->shift = 0;
pl->period = 0;
return percpu_counter_init_irq(&pl->events, 0);
return percpu_counter_init(&pl->events, 0);
}
void prop_local_destroy_percpu(struct prop_local_percpu *pl)