On Wed, Jul 24, 2013 at 2:00 AM, Dave Airlie <airlied@xxxxxxxxx> wrote:
> On Tue, Jul 23, 2013 at 10:43 PM, Rob Clark <robdclark@xxxxxxxxx> wrote:
>> On Tue, Jul 23, 2013 at 8:31 AM, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote:
>>> On Tue, Jul 23, 2013 at 2:07 PM, Rob Clark <robdclark@xxxxxxxxx> wrote:
>>>> On Tue, Jul 16, 2013 at 3:11 AM, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote:
>>>>> Only one callsite and since ->handle_count is not a simple reference
>>>>> count (it can resurrect) it's imo better to be explicit about things
>>>>> than hide the refcount dance.
>>>>
>>>> I'm not really sure I like this one.. I guess it could be that I'm
>>>> just used to the handle-ref stuff, so it doesn't seem odd not-inlined.
>>>> And it does seem kinda odd / unsymmetric to have an unref w/out a
>>>> ref. I guess I kinda like the bikeshed's current color in this case.
>>>
>>> I generally agree but in this case a follow-up patch ("drm/gem: fix up
>>> flink name create race") will change obj->handle_count from an
>>> atomic_t to a normal int protected by the dev->object_name_lock
>>> spinlock. To avoid races we need to hold that spinlock over a few
>>> different instructions, so with the refcounting dance inlined it's
>>> much more obvious that that obj->handle_count is always correctly
>>> protected imo.
>>
>> hmm, ok.. then I'll reserve judgment until I get further through the series ;-)
>>
>> if you do spin another version of the series, it could be worth
>> mentioning this in the commit msg
>>
>
> Just merge this into that series or patch,
>
> deinlining it now it just noise.
Yeah, I'll do so. I've started with a few refactoring patches to get a
clearer picture (since I've implemented&dismissed a few approaches to
fix the flink race until I've settled on this one here), but now this
patch here really looks a bit silly ;-)
-Danie
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/dri-devel
