From: Chris Wilson Date: Wed, 12 Sep 2018 10:11:33 +0000 (+0100) Subject: drm/i915: Reorder execobject[] to insert non-48b objects into the low 4G X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=35e882a4441e73c347aab2c42559e55a1d857fa1;p=linux.git drm/i915: Reorder execobject[] to insert non-48b objects into the low 4G If the caller supplies more than 4G of objects and than one that has to be in the low 4G, it is possible for the low 4G to be full before we attempt to find room for the last object that must be there. As we don't reorder the two types, every pass hits the same problem and we fail with ENOSPC. However, if we impose a little bit of ordering between the two classes of objects, on the second pass we will be able to fit the special object as we do it first. For setups that only use !48b objects, we now reverse the order between passes, hopefully making the subsequent passes more likely to succeed given that we are trying a different order (rather than repeating the previous pass!) v2: Quick one line explanation for the relative priorities given to reservations. Signed-off-by: Chris Wilson Reviewed-by: Joonas Lahtinen Link: https://patchwork.freedesktop.org/patch/msgid/20180912101133.31377-1-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 094c3b1cf2027..bb0980793b486 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -693,9 +693,14 @@ static int eb_reserve(struct i915_execbuffer *eb) eb_unreserve_vma(vma, &eb->flags[i]); if (flags & EXEC_OBJECT_PINNED) + /* Pinned must have their slot */ list_add(&vma->exec_link, &eb->unbound); else if (flags & __EXEC_OBJECT_NEEDS_MAP) + /* Map require the lowest 256MiB (aperture) */ list_add_tail(&vma->exec_link, &eb->unbound); + else if (!(flags & EXEC_OBJECT_SUPPORTS_48B_ADDRESS)) + /* Prioritise 4GiB region for restricted bo */ + list_add(&vma->exec_link, &last); else list_add_tail(&vma->exec_link, &last); }