Replace the open-coded memset loops with the memset32/64 routines that
reduce to a single instruction or two:
add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-83 (-83)
Function old new delta
gen6_ppgtt_clear_range 371 344 -27
gen8_ppgtt_clear_pd 575 519 -56
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Matthew Auld <matthew.auld@xxxxxxxxx>
Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxx>
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 7e79691664e5..f97cc7b437f2 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -809,8 +809,6 @@ static bool gen8_ppgtt_clear_pt(const struct i915_address_space *vm,
u64 start, u64 length)
{
unsigned int num_entries = gen8_pte_count(start, length);
- unsigned int pte = gen8_pte_index(start);
- unsigned int pte_end = pte + num_entries;
gen8_pte_t *vaddr;
GEM_BUG_ON(num_entries > pt->used_ptes);
@@ -820,8 +818,7 @@ static bool gen8_ppgtt_clear_pt(const struct i915_address_space *vm,
return true;
vaddr = kmap_atomic_px(pt);
- while (pte < pte_end)
- vaddr[pte++] = vm->scratch_pte;
+ memset64(vaddr + gen8_pte_index(start), vm->scratch_pte, num_entries);
kunmap_atomic(vaddr);
return false;
@@ -1672,8 +1669,7 @@ static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
while (num_entries) {
struct i915_page_table *pt = ppgtt->base.pd.page_table[pde++];
- const unsigned int end = min(pte + num_entries, GEN6_PTES);
- const unsigned int count = end - pte;
+ const unsigned int count = min(num_entries, GEN6_PTES - pte);
gen6_pte_t *vaddr;
GEM_BUG_ON(pt == vm->scratch_pt);
@@ -1693,9 +1689,7 @@ static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
*/
vaddr = kmap_atomic_px(pt);
- do {
- vaddr[pte++] = scratch_pte;
- } while (pte < end);
+ memset32(vaddr + pte, scratch_pte, count);
kunmap_atomic(vaddr);
pte = 0;
--
2.20.1
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