On Wed, Apr 27, 2016 at 02:12:46PM +0200, Daniel Vetter wrote:
On Wed, Apr 27, 2016 at 12:58:51PM +0100, Chris Wilson wrote:
On Wed, Apr 27, 2016 at 01:50:00PM +0200, Daniel Vetter wrote:
Finally all the core gem and a lot of drivers are entirely free of dev->struct_mutex depencies, and we can start to have an entirely lockless unref path.
To make sure that no one who touches the core code accidentally breaks existing drivers which still require dev->struct_mutex I've made the might_lock check unconditional.
While at it de-inline the ref/unref functions, they've become a bit too big.
v2: Make it not leak like a sieve.
v3: Review from Lucas:
- drop != NULL in pointer checks.
- fixup copypasted kerneldoc to actually match the functions.
Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Alex Deucher alexdeucher@gmail.com Cc: Lucas Stach l.stach@pengutronix.de Reviewed-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Daniel Vetter daniel.vetter@intel.com
drivers/gpu/drm/drm_gem.c | 64 ++++++++++++++++++++++++++++++++++++++--------- include/drm/drmP.h | 15 ++++++++--- include/drm/drm_gem.h | 45 ++------------------------------- 3 files changed, 66 insertions(+), 58 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 25dac31eef37..a4684a306c48 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -788,16 +788,7 @@ drm_gem_object_release(struct drm_gem_object *obj) } EXPORT_SYMBOL(drm_gem_object_release);
-/**
- drm_gem_object_free - free a GEM object
- @kref: kref of the object to free
- Called after the last reference to the object has been lost.
- Must be called holding struct_ mutex
- Frees the object
- */
-void +static void drm_gem_object_free(struct kref *kref) { struct drm_gem_object *obj = @@ -806,10 +797,59 @@ drm_gem_object_free(struct kref *kref)
WARN_ON(!mutex_is_locked(&dev->struct_mutex));
- if (dev->driver->gem_free_object != NULL)
- if (dev->driver->gem_free_object_unlocked)
dev->driver->gem_free_object_unlocked(obj);- else if (dev->driver->gem_free_object) dev->driver->gem_free_object(obj);
} -EXPORT_SYMBOL(drm_gem_object_free);
With my plan, I want to keep drm_gem_object_free exported. The plan being a __drm_gem_object_free_lockless fastpath.
Yeah, but I think we can reexport again in the patch that adds __drm_gem_object_free_lockless. Just not much personally a friend of sprawling EXPORT_SYMBOL when not needed. But I can drop that part too if you feel strongly.
The alternative is to add the function now and then I can just drop the support into my tree and start testing :) -Chris