drm/i915: Replace PIN_NONFAULT with calls to PIN_NOEVICT
authorChris Wilson <chris@chris-wilson.co.uk>
Wed, 21 Aug 2019 12:32:34 +0000 (13:32 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Wed, 21 Aug 2019 13:07:54 +0000 (14:07 +0100)
commit6846895fde05558a39ffcee7631a802a923d9b16
tree1e0540db40effef4ea0e18750f07622b46f3dd2e
parent783877458f1fb5c3ac05d9c89f9506337c2a6f98
drm/i915: Replace PIN_NONFAULT with calls to PIN_NOEVICT

When under severe stress for GTT mappable space, the LRU eviction model
falls off a cliff. We spend all our time scanning the much larger
non-mappable area searching for something within the mappable zone we can
evict. Turn this on its head by only using the full vma for the object if
it is already pinned in the mappable zone or there is sufficient *free*
space to accommodate it (prioritizing speedy reuse). If there is not,
immediately fall back to using small chunks (tilerow for GTT mmap, single
pages for pwrite/relocation) and using random eviction before doing a full
search.

Testcase: igt/gem_concurrent_blt
References: https://bugs.freedesktop.org/show_bug.cgi?id=110848
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190821123234.19194-1-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
drivers/gpu/drm/i915/gem/i915_gem_mman.c
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/i915/i915_gem_evict.c
drivers/gpu/drm/i915/i915_gem_gtt.c
drivers/gpu/drm/i915/i915_gem_gtt.h