From 986dbac4803c7eb2be0d0dac7bc642744502d080 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 14 Jun 2018 19:42:17 +0100 Subject: [PATCH] drm/i915/gtt: Cache the PTE encoding of the scratch page As the most frequent PTE encoding is for the scratch page, cache it upon creation. Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Cc: Mika Kuoppala Cc: Matthew Auld Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20180614184218.1606-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_gtt.c | 20 ++++++++++---------- drivers/gpu/drm/i915/i915_gem_gtt.h | 1 + 2 files changed, 11 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 50160be6357e..dec8a8401c2d 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -640,11 +640,10 @@ static void gen8_initialize_pt(struct i915_address_space *vm, gen8_pte_encode(vm->scratch_page.daddr, I915_CACHE_LLC)); } -static void gen6_initialize_pt(struct i915_address_space *vm, +static void gen6_initialize_pt(struct gen6_hw_ppgtt *ppgtt, struct i915_page_table *pt) { - fill32_px(vm, pt, - vm->pte_encode(vm->scratch_page.daddr, I915_CACHE_LLC, 0)); + fill32_px(&ppgtt->base.vm, pt, ppgtt->scratch_pte); } static struct i915_page_directory *alloc_pd(struct i915_address_space *vm) @@ -1631,9 +1630,7 @@ static struct i915_hw_ppgtt *gen8_ppgtt_create(struct drm_i915_private *i915) static void gen6_dump_ppgtt(struct i915_hw_ppgtt *base, struct seq_file *m) { struct gen6_hw_ppgtt *ppgtt = to_gen6_ppgtt(base); - struct i915_address_space *vm = &base->vm; - const gen6_pte_t scratch_pte = - vm->pte_encode(vm->scratch_page.daddr, I915_CACHE_LLC, 0); + const gen6_pte_t scratch_pte = ppgtt->scratch_pte; struct i915_page_table *pt; u32 pte, pde; @@ -1758,8 +1755,7 @@ static void gen6_ppgtt_clear_range(struct i915_address_space *vm, unsigned int pde = first_entry / GEN6_PTES; unsigned int pte = first_entry % GEN6_PTES; unsigned int num_entries = length >> PAGE_SHIFT; - const gen6_pte_t scratch_pte = - vm->pte_encode(vm->scratch_page.daddr, I915_CACHE_LLC, 0); + const gen6_pte_t scratch_pte = ppgtt->scratch_pte; while (num_entries) { struct i915_page_table *pt = ppgtt->base.pd.page_table[pde++]; @@ -1850,7 +1846,7 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, if (IS_ERR(pt)) goto unwind_out; - gen6_initialize_pt(vm, pt); + gen6_initialize_pt(ppgtt, pt); ppgtt->base.pd.page_table[pde] = pt; if (i915_vma_is_bound(ppgtt->vma, @@ -1888,13 +1884,17 @@ static int gen6_ppgtt_init_scratch(struct gen6_hw_ppgtt *ppgtt) if (ret) return ret; + ppgtt->scratch_pte = + vm->pte_encode(vm->scratch_page.daddr, + I915_CACHE_NONE, PTE_READ_ONLY); + vm->scratch_pt = alloc_pt(vm); if (IS_ERR(vm->scratch_pt)) { cleanup_scratch_page(vm); return PTR_ERR(vm->scratch_pt); } - gen6_initialize_pt(vm, vm->scratch_pt); + gen6_initialize_pt(ppgtt, vm->scratch_pt); gen6_for_all_pdes(unused, &ppgtt->base.pd, pde) ppgtt->base.pd.page_table[pde] = vm->scratch_pt; diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h index 46c95d188580..7ff5cc612771 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.h +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h @@ -412,6 +412,7 @@ struct gen6_hw_ppgtt { struct i915_vma *vma; gen6_pte_t __iomem *pd_addr; + gen6_pte_t scratch_pte; unsigned int pin_count; bool scan_for_unused_pt;