This patch introduces the drm_gem_object_unreference_unlocked
and drm_gem_object_handle_unreference_unlocked functions that
do not require holding struct_mutex.
drm_gem_object_unreference_unlocked calls the new
-gem_free_object_unlocked entry point if available, and
otherwise just takes struct_mutex and just calls -gem_free_object
Signed-off-by: Luca Barbieri l...@luca-barbieri.com
---
drivers/gpu/drm/drm_gem.c | 49
include/drm/drmP.h| 28 +++--
2 files changed, 69 insertions(+), 8 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 8bf3770..4018b3b 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -411,8 +411,19 @@ drm_gem_release(struct drm_device *dev, struct drm_file
*file_private)
mutex_unlock(dev-struct_mutex);
}
+static void
+drm_gem_object_free_common(struct drm_gem_object *obj)
+{
+ struct drm_device *dev = obj-dev;
+ fput(obj-filp);
+ atomic_dec(dev-object_count);
+ atomic_sub(obj-size, dev-object_memory);
+ kfree(obj);
+}
+
/**
* Called after the last reference to the object has been lost.
+ * Must be called holding struct_ mutex
*
* Frees the object
*/
@@ -427,14 +438,40 @@ drm_gem_object_free(struct kref *kref)
if (dev-driver-gem_free_object != NULL)
dev-driver-gem_free_object(obj);
- fput(obj-filp);
- atomic_dec(dev-object_count);
- atomic_sub(obj-size, dev-object_memory);
- kfree(obj);
+ drm_gem_object_free_common(obj);
}
EXPORT_SYMBOL(drm_gem_object_free);
/**
+ * Called after the last reference to the object has been lost.
+ * Must be called without holding struct_mutex
+ *
+ * Frees the object
+ */
+void
+drm_gem_object_free_unlocked(struct kref *kref)
+{
+ struct drm_gem_object *obj = (struct drm_gem_object *) kref;
+ struct drm_device *dev = obj-dev;
+
+ if (dev-driver-gem_free_object_unlocked != NULL)
+ dev-driver-gem_free_object_unlocked(obj);
+ else if (dev-driver-gem_free_object != NULL) {
+ mutex_lock(dev-struct_mutex);
+ dev-driver-gem_free_object(obj);
+ mutex_unlock(dev-struct_mutex);
+ }
+
+ drm_gem_object_free_common(obj);
+}
+EXPORT_SYMBOL(drm_gem_object_free_unlocked);
+
+static void drm_gem_object_ref_bug(struct kref *list_kref)
+{
+ BUG();
+}
+
+/**
* Called after the last handle to the object has been closed
*
* Removes any name for the object. Note that this must be
@@ -458,8 +495,10 @@ drm_gem_object_handle_free(struct kref *kref)
/*
* The object name held a reference to this object, drop
* that now.
+ *
+ * This cannot be the last reference, since the handle holds one
too.
*/
- drm_gem_object_unreference(obj);
+ kref_put(obj-refcount, drm_gem_object_ref_bug);
} else
spin_unlock(dev-object_name_lock);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index ffac157..4a3c4e4 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -801,6 +801,7 @@ struct drm_driver {
*/
int (*gem_init_object) (struct drm_gem_object *obj);
void (*gem_free_object) (struct drm_gem_object *obj);
+ void (*gem_free_object_unlocked) (struct drm_gem_object *obj);
/* vga arb irq handler */
void (*vgaarb_irq)(struct drm_device *dev, bool state);
@@ -1427,6 +1428,7 @@ extern void drm_sysfs_connector_remove(struct
drm_connector *connector);
int drm_gem_init(struct drm_device *dev);
void drm_gem_destroy(struct drm_device *dev);
void drm_gem_object_free(struct kref *kref);
+void drm_gem_object_free_unlocked(struct kref *kref);
struct drm_gem_object *drm_gem_object_alloc(struct drm_device *dev,
size_t size);
void drm_gem_object_handle_free(struct kref *kref);
@@ -1443,10 +1445,15 @@ drm_gem_object_reference(struct drm_gem_object *obj)
static inline void
drm_gem_object_unreference(struct drm_gem_object *obj)
{
- if (obj == NULL)
- return;
+ if (obj != NULL)
+ kref_put(obj-refcount, drm_gem_object_free);
+}
- kref_put(obj-refcount, drm_gem_object_free);
+static inline void
+drm_gem_object_unreference_unlocked(struct drm_gem_object *obj)
+{
+ if (obj != NULL)
+ kref_put(obj-refcount, drm_gem_object_free_unlocked);
}
int drm_gem_handle_create(struct drm_file *file_priv,
@@ -1475,6 +1482,21 @@ drm_gem_object_handle_unreference(struct drm_gem_object
*obj)
drm_gem_object_unreference(obj);
}
+static inline void
+drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj)
+{
+ if (obj == NULL)
+ return;
+
+ /*
+ * Must bump handle count first as this may be the last
+ * ref, in
