db6c2b4151
With full-ppgtt one of the main bottlenecks is the lookup of the VMA underneath the object. For execbuf there is merit in having a very fast direct lookup of ctx:handle to the vma using a hashtree, but that still leaves a large number of other lookups. One way to speed up the lookup would be to use a rhashtable, but that requires extra allocations and may exhibit poor worse case behaviour. An alternative is to use an embedded rbtree, i.e. no extra allocations and deterministic behaviour, but at the slight cost of O(lgN) lookups (instead of O(1) for rhashtable). The major of such tree will be very shallow and so not much slower, and still scales much, much better than the current unsorted list. v2: Bump vma_compare() to return a long, as we return the result of comparing two pointers. References: https://bugs.freedesktop.org/show_bug.cgi?id=87726 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/20161101115400.15647-1-chris@chris-wilson.co.uk |
||
|---|---|---|
| .. | ||
| drm | ||
| host1x | ||
| ipu-v3 | ||
| vga | ||
| Makefile | ||