[Intel-gfx] [PATCH i-g-t] gem_userptr_benchmark: Test overlapping bo mmu notifier performance impact

[Chris Wilson]

On Mon, Jun 01, 2015 at 11:11:15AM +0100, Tvrtko Ursulin wrote:
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> Current userptr kernel implementation downgrades tracking VMA ranges (real
> userspace ones) to an inefficient linear walk for any process which has
> instantiated overlapping userptr objects.
> 
> This adds a test which shows the performance cliff on, most visibly, generic
> userspace mmap(2) and munmap(2) operations between unsync, non-overlapping
> and overlapping userptr objects.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Thomas Daniel <thomas.daniel at intel.com>

Looked good, pushed.
Thanks,
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre