[Intel-gfx] [PATCH 09/14] drm: Protect authmagic with master_mutex

[Daniel Vetter]

On Wed, Jun 15, 2016 at 12:54:24PM +0100, Chris Wilson wrote:
> On Tue, Jun 14, 2016 at 08:51:04PM +0200, Daniel Vetter wrote:
> > Simplifies cleanup, and there's no reason drivers should ever care
> > about authmagic at all - it's all handled in the core.
> > 
> > And with that, Ladies and Gentlemen, it's time to pop the champagen
> > and celebrate: dev->struct_mutex is now officially gone from modern
> > drivers, and if a driver is using gem_free_object_unlocked and doesn't
> > do anything else silly it's positively impossible to ever touch
> > dev->struct_mutex at runtime, anywhere.
> 
> Still keen to know what the fuss is all about.

I hate sprawling locks, and go all ocd about them. There's not really
anything else. It also makes reviewing changes painful since you have to
re-read every code that somehow interacts with your lock. I much prefer
locking where each part fits into my brain, and that one is of pityful
capacity ;-)
-Daniel

>  
> > Well except for the mutex_init on driver load ;-)
> > 
> > Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
> -Chris
> 
> -- 
> Chris Wilson, Intel Open Source Technology Centre

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch