From: Chris Wilson chris@chris-wilson.co.uk
After calling lock_set_subclass() the lock _must_ be used, or else lockdep's internal nr_used_locks becomes unbalanced. Extract the little utility function to i915_utils.c
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Thomas Hellström thomas.hellstrom@linux.intel.com Reviewed-by: Thomas Hellström thomas.hellstrom@linux.intel.com Signed-off-by: Tvrtko Ursulin tvrtko.ursulin@intel.com --- drivers/gpu/drm/i915/gt/intel_engine_cs.c | 13 +------------ drivers/gpu/drm/i915/i915_utils.c | 15 +++++++++++++++ drivers/gpu/drm/i915/i915_utils.h | 7 +++++++ 3 files changed, 23 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c index 3f9a811eb02b..15566819539f 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c @@ -794,18 +794,7 @@ intel_engine_init_active(struct intel_engine_cs *engine, unsigned int subclass)
spin_lock_init(&engine->active.lock); lockdep_set_subclass(&engine->active.lock, subclass); - - /* - * Due to an interesting quirk in lockdep's internal debug tracking, - * after setting a subclass we must ensure the lock is used. Otherwise, - * nr_unused_locks is incremented once too often. - */ -#ifdef CONFIG_DEBUG_LOCK_ALLOC - local_irq_disable(); - lock_map_acquire(&engine->active.lock.dep_map); - lock_map_release(&engine->active.lock.dep_map); - local_irq_enable(); -#endif + mark_lock_used_irq(&engine->active.lock); }
static struct intel_context * diff --git a/drivers/gpu/drm/i915/i915_utils.c b/drivers/gpu/drm/i915/i915_utils.c index 90c7f0c4838c..894de60833ec 100644 --- a/drivers/gpu/drm/i915/i915_utils.c +++ b/drivers/gpu/drm/i915/i915_utils.c @@ -127,3 +127,18 @@ void fs_reclaim_taints_mutex(struct mutex *mutex)
fs_reclaim_release(GFP_KERNEL); } + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +void __mark_lock_used_irq(struct lockdep_map *lock) +{ + /* + * Due to an interesting quirk in lockdep's internal debug tracking, + * after setting a subclass we must ensure the lock is used. Otherwise, + * nr_unused_locks is incremented once too often. + */ + local_irq_disable(); + lock_map_acquire(lock); + lock_map_release(lock); + local_irq_enable(); +} +#endif diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h index 4133d5193839..c3d234133da7 100644 --- a/drivers/gpu/drm/i915/i915_utils.h +++ b/drivers/gpu/drm/i915/i915_utils.h @@ -455,6 +455,13 @@ static inline bool timer_expired(const struct timer_list *t) return timer_active(t) && !timer_pending(t); }
+#ifdef CONFIG_DEBUG_LOCK_ALLOC +void __mark_lock_used_irq(struct lockdep_map *lock); +#define mark_lock_used_irq(lock) __mark_lock_used_irq(&(lock)->dep_map) +#else +#define mark_lock_used_irq(lock) +#endif + /* * This is a lookalike for IS_ENABLED() that takes a kconfig value, * e.g. CONFIG_DRM_I915_SPIN_REQUEST, and evaluates whether it is non-zero