... other mutation of the handle idr is still serialised using spin locks.

Signed-off-by: Chris Wilson chris@chris-wilson.co.uk --- drivers/gpu/drm/drm_gem.c | 20 ++++++++------------ 1 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index ea1c4b0..ce63a14 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -184,7 +184,6 @@ EXPORT_SYMBOL(drm_gem_object_alloc); static int drm_gem_handle_delete(struct drm_file *filp, u32 handle) { - struct drm_device *dev; struct drm_gem_object *obj;

/* This is gross. The idr system doesn't let us try a delete and @@ -204,12 +203,13 @@ drm_gem_handle_delete(struct drm_file *filp, u32 handle) spin_unlock(&filp->table_lock); return -EINVAL; } - dev = obj->dev;

/* Release reference and decrement refcount. */ idr_remove(&filp->object_idr, handle); spin_unlock(&filp->table_lock);

+ synchronize_rcu(); + drm_gem_object_handle_unreference_unlocked(obj);

return 0; @@ -257,18 +257,14 @@ drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, { struct drm_gem_object *obj;

- spin_lock(&filp->table_lock); + rcu_read_lock();

/* Check if we currently have a reference on the object */ obj = idr_find(&filp->object_idr, handle); - if (obj == NULL) { - spin_unlock(&filp->table_lock); - return NULL; - } - - drm_gem_object_reference(obj); + if (obj) + drm_gem_object_reference(obj);

- spin_unlock(&filp->table_lock); + rcu_read_unlock();

return obj; } @@ -363,11 +359,11 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data, if (!(dev->driver->driver_features & DRIVER_GEM)) return -ENODEV;

- spin_lock(&dev->object_name_lock); + rcu_read_lock(); obj = idr_find(&dev->object_name_idr, (int) args->name); if (obj) drm_gem_object_reference(obj); - spin_unlock(&dev->object_name_lock); + rcu_read_unlock(); if (!obj) return -ENOENT;