Commit 6eebfe8a authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915/gtt: Use shallow dma pages for scratch 



We only use the dma pages for scratch, and so do not need to allocate
the extra storage for the shadow page directory.

v2: Refrain from reintroducing I915_PDES

Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: default avatarMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190712075818.20616-1-chris@chris-wilson.co.uk
parent 3e1f0a51

drivers/gpu/drm/i915/i915_gem_gtt.c

+83 −113
Original line number Diff line number Diff line
@@ -594,26 +594,17 @@ static void cleanup_page_dma(struct i915_address_space *vm, 


#define kmap_atomic_px(px) kmap_atomic(px_base(px)->page)



#define fill_px(vm, px, v) fill_page_dma((vm), px_base(px), (v))

#define fill32_px(vm, px, v) fill_page_dma_32((vm), px_base(px), (v))



static void fill_page_dma(struct i915_address_space *vm,

			  struct i915_page_dma *p,

			  const u64 val)

static void

fill_page_dma(const struct i915_page_dma *p, const u64 val, unsigned int count)

{

	u64 * const vaddr = kmap_atomic(p->page);



	memset64(vaddr, val, PAGE_SIZE / sizeof(val));



	kunmap_atomic(vaddr);

	kunmap_atomic(memset64(kmap_atomic(p->page), val, count));

}



static void fill_page_dma_32(struct i915_address_space *vm,

			     struct i915_page_dma *p,

			     const u32 v)

{

	fill_page_dma(vm, p, (u64)v << 32 | v);

}

#define fill_px(px, v) fill_page_dma(px_base(px), (v), PAGE_SIZE / sizeof(u64))

#define fill32_px(px, v) do {						\

	u64 v__ = lower_32_bits(v);					\

	fill_px((px), v__ << 32 | v__);					\

} while (0)



static int

setup_scratch_page(struct i915_address_space *vm, gfp_t gfp)
@@ -687,6 +678,21 @@ static void cleanup_scratch_page(struct i915_address_space *vm) 
	__free_pages(p->page, order);

}



static void free_scratch(struct i915_address_space *vm)

{

	if (!vm->scratch_page.daddr) /* set to 0 on clones */

		return;



	if (vm->scratch_pdp.daddr)

		cleanup_page_dma(vm, &vm->scratch_pdp);

	if (vm->scratch_pd.daddr)

		cleanup_page_dma(vm, &vm->scratch_pd);

	if (vm->scratch_pt.daddr)

		cleanup_page_dma(vm, &vm->scratch_pt);



	cleanup_scratch_page(vm);

}



static struct i915_page_table *alloc_pt(struct i915_address_space *vm)

{

	struct i915_page_table *pt;
@@ -711,18 +717,6 @@ static void free_pt(struct i915_address_space *vm, struct i915_page_table *pt) 
	kfree(pt);

}



static void gen8_initialize_pt(struct i915_address_space *vm,

			       struct i915_page_table *pt)

{

	fill_px(vm, pt, vm->scratch_pte);

}



static void gen6_initialize_pt(struct i915_address_space *vm,

			       struct i915_page_table *pt)

{

	fill32_px(vm, pt, vm->scratch_pte);

}



static struct i915_page_directory *__alloc_pd(void)

{

	struct i915_page_directory *pd;
@@ -765,9 +759,11 @@ static void free_pd(struct i915_address_space *vm, 
	kfree(pd);

}



#define init_pd(vm, pd, to) {					\

	fill_px((vm), (pd), gen8_pde_encode(px_dma(to), I915_CACHE_LLC)); \

	memset_p((pd)->entry, (to), 512);				\

static void init_pd(struct i915_page_directory *pd,

		    struct i915_page_dma *scratch)

{

	fill_px(pd, gen8_pde_encode(scratch->daddr, I915_CACHE_LLC));

	memset_p(pd->entry, scratch, 512);

}



static inline void
@@ -869,12 +865,11 @@ static void gen8_ppgtt_clear_pd(struct i915_address_space *vm, 
	u32 pde;



	gen8_for_each_pde(pt, pd, start, length, pde) {

		GEM_BUG_ON(pt == vm->scratch_pt);

		GEM_BUG_ON(px_base(pt) == &vm->scratch_pt);



		atomic_inc(&pt->used);

		gen8_ppgtt_clear_pt(vm, pt, start, length);

		if (release_pd_entry(pd, pde, &pt->used,

				     px_base(vm->scratch_pt)))

		if (release_pd_entry(pd, pde, &pt->used, &vm->scratch_pt))

			free_pt(vm, pt);

	}

}
@@ -890,12 +885,11 @@ static void gen8_ppgtt_clear_pdp(struct i915_address_space *vm, 
	unsigned int pdpe;



	gen8_for_each_pdpe(pd, pdp, start, length, pdpe) {

		GEM_BUG_ON(pd == vm->scratch_pd);

		GEM_BUG_ON(px_base(pd) == &vm->scratch_pd);



		atomic_inc(&pd->used);

		gen8_ppgtt_clear_pd(vm, pd, start, length);

		if (release_pd_entry(pdp, pdpe, &pd->used,

				     px_base(vm->scratch_pd)))

		if (release_pd_entry(pdp, pdpe, &pd->used, &vm->scratch_pd))

			free_pd(vm, pd);

	}

}
@@ -921,12 +915,11 @@ static void gen8_ppgtt_clear_4lvl(struct i915_address_space *vm, 
	GEM_BUG_ON(!i915_vm_is_4lvl(vm));



	gen8_for_each_pml4e(pdp, pml4, start, length, pml4e) {

		GEM_BUG_ON(pdp == vm->scratch_pdp);

		GEM_BUG_ON(px_base(pdp) == &vm->scratch_pdp);



		atomic_inc(&pdp->used);

		gen8_ppgtt_clear_pdp(vm, pdp, start, length);

		if (release_pd_entry(pml4, pml4e, &pdp->used,

				     px_base(vm->scratch_pdp)))

		if (release_pd_entry(pml4, pml4e, &pdp->used, &vm->scratch_pdp))

			free_pd(vm, pdp);

	}

}
@@ -1181,7 +1174,7 @@ static void gen8_free_page_tables(struct i915_address_space *vm, 
	int i;



	for (i = 0; i < I915_PDES; i++) {

		if (pd->entry[i] != vm->scratch_pt)

		if (pd->entry[i] != &vm->scratch_pt)

			free_pt(vm, pd->entry[i]);

	}

}
@@ -1218,37 +1211,34 @@ static int gen8_init_scratch(struct i915_address_space *vm) 
				I915_CACHE_LLC,

				vm->has_read_only);



	vm->scratch_pt = alloc_pt(vm);

	if (IS_ERR(vm->scratch_pt)) {

		ret = PTR_ERR(vm->scratch_pt);

	if (unlikely(setup_page_dma(vm, &vm->scratch_pt))) {

		ret = -ENOMEM;

		goto free_scratch_page;

	}

	fill_px(&vm->scratch_pt, vm->scratch_pte);



	vm->scratch_pd = alloc_pd(vm);

	if (IS_ERR(vm->scratch_pd)) {

		ret = PTR_ERR(vm->scratch_pd);

	if (unlikely(setup_page_dma(vm, &vm->scratch_pd))) {

		ret = -ENOMEM;

		goto free_pt;

	}

	fill_px(&vm->scratch_pd,

		gen8_pde_encode(vm->scratch_pt.daddr, I915_CACHE_LLC));



	if (i915_vm_is_4lvl(vm)) {

		vm->scratch_pdp = alloc_pd(vm);

		if (IS_ERR(vm->scratch_pdp)) {

			ret = PTR_ERR(vm->scratch_pdp);

		if (unlikely(setup_page_dma(vm, &vm->scratch_pdp))) {

			ret = -ENOMEM;

			goto free_pd;

		}

		fill_px(&vm->scratch_pdp,

			gen8_pde_encode(vm->scratch_pd.daddr, I915_CACHE_LLC));

	}



	gen8_initialize_pt(vm, vm->scratch_pt);

	init_pd(vm, vm->scratch_pd, vm->scratch_pt);

	if (i915_vm_is_4lvl(vm))

		init_pd(vm, vm->scratch_pdp, vm->scratch_pd);



	return 0;



free_pd:

	free_pd(vm, vm->scratch_pd);

	cleanup_page_dma(vm, &vm->scratch_pd);

free_pt:

	free_pt(vm, vm->scratch_pt);

	cleanup_page_dma(vm, &vm->scratch_pt);

free_scratch_page:

	cleanup_scratch_page(vm);
@@ -1292,18 +1282,6 @@ static int gen8_ppgtt_notify_vgt(struct i915_ppgtt *ppgtt, bool create) 
	return 0;

}



static void gen8_free_scratch(struct i915_address_space *vm)

{

	if (!vm->scratch_page.daddr)

		return;



	if (i915_vm_is_4lvl(vm))

		free_pd(vm, vm->scratch_pdp);

	free_pd(vm, vm->scratch_pd);

	free_pt(vm, vm->scratch_pt);

	cleanup_scratch_page(vm);

}



static void gen8_ppgtt_cleanup_3lvl(struct i915_address_space *vm,

				    struct i915_page_directory *pdp)

{
@@ -1311,7 +1289,7 @@ static void gen8_ppgtt_cleanup_3lvl(struct i915_address_space *vm, 
	int i;



	for (i = 0; i < pdpes; i++) {

		if (pdp->entry[i] == vm->scratch_pd)

		if (pdp->entry[i] == &vm->scratch_pd)

			continue;



		gen8_free_page_tables(vm, pdp->entry[i]);
@@ -1329,7 +1307,7 @@ static void gen8_ppgtt_cleanup_4lvl(struct i915_ppgtt *ppgtt) 
	for (i = 0; i < GEN8_PML4ES_PER_PML4; i++) {

		struct i915_page_directory *pdp = i915_pdp_entry(pml4, i);



		if (pdp == ppgtt->vm.scratch_pdp)

		if (px_base(pdp) == &ppgtt->vm.scratch_pdp)

			continue;



		gen8_ppgtt_cleanup_3lvl(&ppgtt->vm, pdp);
@@ -1351,7 +1329,7 @@ static void gen8_ppgtt_cleanup(struct i915_address_space *vm) 
	else

		gen8_ppgtt_cleanup_3lvl(&ppgtt->vm, ppgtt->pd);



	gen8_free_scratch(vm);

	free_scratch(vm);

}



static int gen8_ppgtt_alloc_pd(struct i915_address_space *vm,
@@ -1367,7 +1345,7 @@ static int gen8_ppgtt_alloc_pd(struct i915_address_space *vm, 
	gen8_for_each_pde(pt, pd, start, length, pde) {

		const int count = gen8_pte_count(start, length);



		if (pt == vm->scratch_pt) {

		if (px_base(pt) == &vm->scratch_pt) {

			spin_unlock(&pd->lock);



			pt = fetch_and_zero(&alloc);
@@ -1379,10 +1357,10 @@ static int gen8_ppgtt_alloc_pd(struct i915_address_space *vm, 
			}



			if (count < GEN8_PTES || intel_vgpu_active(vm->i915))

				gen8_initialize_pt(vm, pt);

				fill_px(pt, vm->scratch_pte);



			spin_lock(&pd->lock);

			if (pd->entry[pde] == vm->scratch_pt) {

			if (pd->entry[pde] == &vm->scratch_pt) {

				set_pd_entry(pd, pde, pt);

			} else {

				alloc = pt;
@@ -1414,7 +1392,7 @@ static int gen8_ppgtt_alloc_pdp(struct i915_address_space *vm, 


	spin_lock(&pdp->lock);

	gen8_for_each_pdpe(pd, pdp, start, length, pdpe) {

		if (pd == vm->scratch_pd) {

		if (px_base(pd) == &vm->scratch_pd) {

			spin_unlock(&pdp->lock);



			pd = fetch_and_zero(&alloc);
@@ -1425,10 +1403,10 @@ static int gen8_ppgtt_alloc_pdp(struct i915_address_space *vm, 
				goto unwind;

			}



			init_pd(vm, pd, vm->scratch_pt);

			init_pd(pd, &vm->scratch_pt);



			spin_lock(&pdp->lock);

			if (pdp->entry[pdpe] == vm->scratch_pd) {

			if (pdp->entry[pdpe] == &vm->scratch_pd) {

				set_pd_entry(pdp, pdpe, pd);

			} else {

				alloc = pd;
@@ -1449,7 +1427,7 @@ static int gen8_ppgtt_alloc_pdp(struct i915_address_space *vm, 
	goto out;



unwind_pd:

	if (release_pd_entry(pdp, pdpe, &pd->used, px_base(vm->scratch_pd)))

	if (release_pd_entry(pdp, pdpe, &pd->used, &vm->scratch_pd))

		free_pd(vm, pd);

unwind:

	gen8_ppgtt_clear_pdp(vm, pdp, from, start - from);
@@ -1478,7 +1456,7 @@ static int gen8_ppgtt_alloc_4lvl(struct i915_address_space *vm, 


	spin_lock(&pml4->lock);

	gen8_for_each_pml4e(pdp, pml4, start, length, pml4e) {

		if (pdp == vm->scratch_pdp) {

		if (px_base(pdp) == &vm->scratch_pdp) {

			spin_unlock(&pml4->lock);



			pdp = fetch_and_zero(&alloc);
@@ -1489,10 +1467,10 @@ static int gen8_ppgtt_alloc_4lvl(struct i915_address_space *vm, 
				goto unwind;

			}



			init_pd(vm, pdp, vm->scratch_pd);

			init_pd(pdp, &vm->scratch_pd);



			spin_lock(&pml4->lock);

			if (pml4->entry[pml4e] == vm->scratch_pdp) {

			if (pml4->entry[pml4e] == &vm->scratch_pdp) {

				set_pd_entry(pml4, pml4e, pdp);

			} else {

				alloc = pdp;
@@ -1513,7 +1491,7 @@ static int gen8_ppgtt_alloc_4lvl(struct i915_address_space *vm, 
	goto out;



unwind_pdp:

	if (release_pd_entry(pml4, pml4e, &pdp->used, px_base(vm->scratch_pdp)))

	if (release_pd_entry(pml4, pml4e, &pdp->used, &vm->scratch_pdp))

		free_pd(vm, pdp);

unwind:

	gen8_ppgtt_clear_4lvl(vm, from, start - from);
@@ -1537,7 +1515,7 @@ static int gen8_preallocate_top_level_pdp(struct i915_ppgtt *ppgtt) 
		if (IS_ERR(pd))

			goto unwind;



		init_pd(vm, pd, vm->scratch_pt);

		init_pd(pd, &vm->scratch_pt);

		set_pd_entry(pdp, pdpe, pd);

	}
@@ -1568,10 +1546,10 @@ static void ppgtt_init(struct i915_ppgtt *ppgtt, struct intel_gt *gt) 


static void init_pd_n(struct i915_address_space *vm,

		      struct i915_page_directory *pd,

		      struct i915_page_directory *to,

		      struct i915_page_dma *to,

		      const unsigned int entries)

{

	const u64 daddr = gen8_pde_encode(px_dma(to), I915_CACHE_LLC);

	const u64 daddr = gen8_pde_encode(to->daddr, I915_CACHE_LLC);

	u64 * const vaddr = kmap_atomic(pd->base.page);



	memset64(vaddr, daddr, entries);
@@ -1588,7 +1566,7 @@ gen8_alloc_top_pd(struct i915_address_space *vm) 
	if (i915_vm_is_4lvl(vm)) {

		pd = alloc_pd(vm);

		if (!IS_ERR(pd))

			init_pd(vm, pd, vm->scratch_pdp);

			init_pd(pd, &vm->scratch_pdp);



		return pd;

	}
@@ -1605,7 +1583,7 @@ gen8_alloc_top_pd(struct i915_address_space *vm) 
		return ERR_PTR(-ENOMEM);

	}



	init_pd_n(vm, pd, vm->scratch_pd, GEN8_3LVL_PDPES);

	init_pd_n(vm, pd, &vm->scratch_pd, GEN8_3LVL_PDPES);



	return pd;

}
@@ -1678,7 +1656,7 @@ static struct i915_ppgtt *gen8_ppgtt_create(struct drm_i915_private *i915) 
err_free_pd:

	free_pd(&ppgtt->vm, ppgtt->pd);

err_free_scratch:

	gen8_free_scratch(&ppgtt->vm);

	free_scratch(&ppgtt->vm);

err_free:

	kfree(ppgtt);

	return ERR_PTR(err);
@@ -1763,7 +1741,7 @@ static void gen6_ppgtt_clear_range(struct i915_address_space *vm, 
		const unsigned int count = min(num_entries, GEN6_PTES - pte);

		gen6_pte_t *vaddr;



		GEM_BUG_ON(pt == vm->scratch_pt);

		GEM_BUG_ON(px_base(pt) == &vm->scratch_pt);



		num_entries -= count;
@@ -1800,7 +1778,7 @@ static void gen6_ppgtt_insert_entries(struct i915_address_space *vm, 
	struct sgt_dma iter = sgt_dma(vma);

	gen6_pte_t *vaddr;



	GEM_BUG_ON(i915_pt_entry(pd, act_pt) == vm->scratch_pt);

	GEM_BUG_ON(pd->entry[act_pt] == &vm->scratch_pt);



	vaddr = kmap_atomic_px(i915_pt_entry(pd, act_pt));

	do {
@@ -1845,7 +1823,7 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, 
	gen6_for_each_pde(pt, pd, start, length, pde) {

		const unsigned int count = gen6_pte_count(start, length);



		if (pt == vm->scratch_pt) {

		if (px_base(pt) == &vm->scratch_pt) {

			spin_unlock(&pd->lock);



			pt = fetch_and_zero(&alloc);
@@ -1856,10 +1834,10 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, 
				goto unwind_out;

			}



			gen6_initialize_pt(vm, pt);

			fill32_px(pt, vm->scratch_pte);



			spin_lock(&pd->lock);

			if (pd->entry[pde] == vm->scratch_pt) {

			if (pd->entry[pde] == &vm->scratch_pt) {

				pd->entry[pde] = pt;

				if (i915_vma_is_bound(ppgtt->vma,

						      I915_VMA_GLOBAL_BIND)) {
@@ -1908,26 +1886,18 @@ static int gen6_ppgtt_init_scratch(struct gen6_ppgtt *ppgtt) 
					 I915_CACHE_NONE,

					 PTE_READ_ONLY);



	vm->scratch_pt = alloc_pt(vm);

	if (IS_ERR(vm->scratch_pt)) {

	if (unlikely(setup_page_dma(vm, &vm->scratch_pt))) {

		cleanup_scratch_page(vm);

		return PTR_ERR(vm->scratch_pt);

		return -ENOMEM;

	}



	gen6_initialize_pt(vm, vm->scratch_pt);

	fill32_px(&vm->scratch_pt, vm->scratch_pte);



	gen6_for_all_pdes(unused, pd, pde)

		pd->entry[pde] = vm->scratch_pt;

		pd->entry[pde] = &vm->scratch_pt;



	return 0;

}



static void gen6_ppgtt_free_scratch(struct i915_address_space *vm)

{

	free_pt(vm, vm->scratch_pt);

	cleanup_scratch_page(vm);

}



static void gen6_ppgtt_free_pd(struct gen6_ppgtt *ppgtt)

{

	struct i915_page_directory * const pd = ppgtt->base.pd;
@@ -1935,7 +1905,7 @@ static void gen6_ppgtt_free_pd(struct gen6_ppgtt *ppgtt) 
	u32 pde;



	gen6_for_all_pdes(pt, pd, pde)

		if (pt != ppgtt->base.vm.scratch_pt)

		if (px_base(pt) != &ppgtt->base.vm.scratch_pt)

			free_pt(&ppgtt->base.vm, pt);

}
@@ -1950,7 +1920,7 @@ static void gen6_ppgtt_cleanup(struct i915_address_space *vm) 
	mutex_unlock(&i915->drm.struct_mutex);



	gen6_ppgtt_free_pd(ppgtt);

	gen6_ppgtt_free_scratch(vm);

	free_scratch(vm);

	kfree(ppgtt->base.pd);

}
@@ -1993,7 +1963,7 @@ static void pd_vma_unbind(struct i915_vma *vma) 
{

	struct gen6_ppgtt *ppgtt = vma->private;

	struct i915_page_directory * const pd = ppgtt->base.pd;

	struct i915_page_table * const scratch_pt = ppgtt->base.vm.scratch_pt;

	struct i915_page_dma * const scratch = &ppgtt->base.vm.scratch_pt;

	struct i915_page_table *pt;

	unsigned int pde;
@@ -2002,11 +1972,11 @@ static void pd_vma_unbind(struct i915_vma *vma) 


	/* Free all no longer used page tables */

	gen6_for_all_pdes(pt, ppgtt->base.pd, pde) {

		if (atomic_read(&pt->used) || pt == scratch_pt)

		if (px_base(pt) == scratch || atomic_read(&pt->used))

			continue;



		free_pt(&ppgtt->base.vm, pt);

		pd->entry[pde] = scratch_pt;

		pd->entry[pde] = scratch;

	}



	ppgtt->scan_for_unused_pt = false;
@@ -2148,7 +2118,7 @@ static struct i915_ppgtt *gen6_ppgtt_create(struct drm_i915_private *i915) 
	return &ppgtt->base;



err_scratch:

	gen6_ppgtt_free_scratch(&ppgtt->base.vm);

	free_scratch(&ppgtt->base.vm);

err_pd:

	kfree(ppgtt->base.pd);

err_free:

drivers/gpu/drm/i915/i915_gem_gtt.h

+17 −6
Original line number Diff line number Diff line
@@ -240,9 +240,6 @@ struct i915_page_dma { 
	};

};



#define px_base(px) (&(px)->base)

#define px_dma(px) (px_base(px)->daddr)



struct i915_page_table {

	struct i915_page_dma base;

	atomic_t used;
@@ -255,6 +252,20 @@ struct i915_page_directory { 
	void *entry[512];

};



#define __px_choose_expr(x, type, expr, other) \

	__builtin_choose_expr( \

	__builtin_types_compatible_p(typeof(x), type) || \

	__builtin_types_compatible_p(typeof(x), const type), \

	({ type __x = (type)(x); expr; }), \

	other)



#define px_base(px) \

	__px_choose_expr(px, struct i915_page_dma *, __x, \

	__px_choose_expr(px, struct i915_page_table *, &__x->base, \

	__px_choose_expr(px, struct i915_page_directory *, &__x->base, \

	(void)0)))

#define px_dma(px) (px_base(px)->daddr)



struct i915_vma_ops {

	/* Map an object into an address space with the given cache flags. */

	int (*bind_vma)(struct i915_vma *vma,
@@ -304,9 +315,9 @@ struct i915_address_space { 
	u64 scratch_pte;

	int scratch_order;

	struct i915_page_dma scratch_page;

	struct i915_page_table *scratch_pt;

	struct i915_page_directory *scratch_pd;

	struct i915_page_directory *scratch_pdp; /* GEN8+ & 48b PPGTT */

	struct i915_page_dma scratch_pt;

	struct i915_page_dma scratch_pd;

	struct i915_page_dma scratch_pdp; /* GEN8+ & 48b PPGTT */



	/**

	 * List of vma currently bound.

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