[Intel-gfx] [PATCH 06/66] drm/i915: Export a preallocate variant of i915_active_acquire()

[Thomas Hellström (Intel)]

On 2020-07-15 13:50, Chris Wilson wrote:
> Sometimes we have to be very careful not to allocate underneath a mutex
> (or spinlock) and yet still want to track activity. Enter
> i915_active_acquire_for_context(). This raises the activity counter on
> i915_active prior to use and ensures that the fence-tree contains a slot
> for the context.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   .../gpu/drm/i915/gem/i915_gem_execbuffer.c    |   2 +-
>   drivers/gpu/drm/i915/gt/intel_timeline.c      |   4 +-
>   drivers/gpu/drm/i915/i915_active.c            | 136 +++++++++++++++---
>   drivers/gpu/drm/i915/i915_active.h            |  12 +-
>   4 files changed, 126 insertions(+), 28 deletions(-)
>
...
>   	/*
>   	 * We track the most recently used timeline to skip a rbtree search
> @@ -230,8 +260,8 @@ active_instance(struct i915_active *ref, struct intel_timeline *tl)
>   	 * after the previous activity has been retired, or if it matches the
>   	 * current timeline.
>   	 */


In addition to Tvrtko's comments, Should this comment be moved to 
__active_lookup() ?

/Thomas