[Intel-gfx] [PATCH 14/19] drm/i915: Remove bitmap tracking for used-pdpes
Chris Wilson
chris at chris-wilson.co.uk
Thu Feb 2 15:02:43 UTC 2017
We only operate on known extents (both for alloc/clear) and so we can use
both the knowledge of the bind/unbind range along with the knowledge of
the existing pagetable to avoid having to allocate temporary and
auxiliary bitmaps.
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
drivers/gpu/drm/i915/i915_gem_gtt.c | 275 +++++++++++-------------------------
drivers/gpu/drm/i915/i915_gem_gtt.h | 3 +-
2 files changed, 84 insertions(+), 194 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 15e95904931f..99319461f86c 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -526,24 +526,13 @@ static void gen8_initialize_pd(struct i915_address_space *vm,
static int __pdp_init(struct i915_address_space *vm,
struct i915_page_directory_pointer *pdp)
{
- size_t pdpes = I915_PDPES_PER_PDP(vm->i915);
- int i;
-
- pdp->used_pdpes = kcalloc(BITS_TO_LONGS(pdpes),
- sizeof(unsigned long),
- GFP_KERNEL);
- if (!pdp->used_pdpes)
- return -ENOMEM;
+ const unsigned int pdpes = I915_PDPES_PER_PDP(vm->i915);
+ unsigned int i;
pdp->page_directory = kmalloc_array(pdpes, sizeof(*pdp->page_directory),
- GFP_KERNEL);
- if (!pdp->page_directory) {
- kfree(pdp->used_pdpes);
- /* the PDP might be the statically allocated top level. Keep it
- * as clean as possible */
- pdp->used_pdpes = NULL;
+ GFP_KERNEL | __GFP_NOWARN);
+ if (unlikely(!pdp->page_directory))
return -ENOMEM;
- }
for (i = 0; i < pdpes; i++)
pdp->page_directory[i] = vm->scratch_pd;
@@ -553,7 +542,6 @@ static int __pdp_init(struct i915_address_space *vm,
static void __pdp_fini(struct i915_page_directory_pointer *pdp)
{
- kfree(pdp->used_pdpes);
kfree(pdp->page_directory);
pdp->page_directory = NULL;
}
@@ -611,23 +599,12 @@ static void gen8_initialize_pdp(struct i915_address_space *vm,
static void gen8_initialize_pml4(struct i915_address_space *vm,
struct i915_pml4 *pml4)
{
- gen8_ppgtt_pml4e_t scratch_pml4e;
-
- scratch_pml4e = gen8_pml4e_encode(px_dma(vm->scratch_pdp),
- I915_CACHE_LLC);
-
- fill_px(vm, pml4, scratch_pml4e);
-}
-
-static void
-gen8_ppgtt_set_pml4e(struct i915_pml4 *pml4,
- struct i915_page_directory_pointer *pdp,
- int index)
-{
- gen8_ppgtt_pml4e_t *pagemap = kmap_atomic_px(pml4);
+ unsigned int i;
- pagemap[index] = gen8_pml4e_encode(px_dma(pdp), I915_CACHE_LLC);
- kunmap_atomic(pagemap);
+ fill_px(vm, pml4,
+ gen8_pml4e_encode(px_dma(vm->scratch_pdp), I915_CACHE_LLC));
+ for (i = 0; i < GEN8_PML4ES_PER_PML4; i++)
+ pml4->pdps[i] = vm->scratch_pdp;
}
/* Broadwell Page Directory Pointer Descriptors */
@@ -781,15 +758,12 @@ static bool gen8_ppgtt_clear_pdp(struct i915_address_space *vm,
continue;
gen8_ppgtt_set_pdpe(vm, pdp, vm->scratch_pd, pdpe);
- __clear_bit(pdpe, pdp->used_pdpes);
+ pdp->used_pdpes--;
free_pd(vm, pd);
}
- if (bitmap_empty(pdp->used_pdpes, I915_PDPES_PER_PDP(dev_priv)))
- return true;
-
- return false;
+ return !pdp->used_pdpes;
}
static void gen8_ppgtt_clear_3lvl(struct i915_address_space *vm,
@@ -798,6 +772,19 @@ static void gen8_ppgtt_clear_3lvl(struct i915_address_space *vm,
gen8_ppgtt_clear_pdp(vm, &i915_vm_to_ppgtt(vm)->pdp, start, length);
}
+static void gen8_ppgtt_set_pml4e(struct i915_pml4 *pml4,
+ struct i915_page_directory_pointer *pdp,
+ unsigned int pml4e)
+{
+ gen8_ppgtt_pml4e_t *vaddr;
+
+ pml4->pdps[pml4e] = pdp;
+
+ vaddr = kmap_atomic_px(pml4);
+ vaddr[pml4e] = gen8_pml4e_encode(px_dma(pdp), I915_CACHE_LLC);
+ kunmap_atomic(vaddr);
+}
+
/* Removes entries from a single pml4.
* This is the top-level structure in 4-level page tables used on gen8+.
* Empty entries are always scratch pml4e.
@@ -808,19 +795,18 @@ static void gen8_ppgtt_clear_4lvl(struct i915_address_space *vm,
struct i915_hw_ppgtt *ppgtt = i915_vm_to_ppgtt(vm);
struct i915_pml4 *pml4 = &ppgtt->pml4;
struct i915_page_directory_pointer *pdp;
- uint64_t pml4e;
+ unsigned int pml4e;
GEM_BUG_ON(!USES_FULL_48BIT_PPGTT(vm->i915));
gen8_for_each_pml4e(pdp, pml4, start, length, pml4e) {
- if (WARN_ON(!pml4->pdps[pml4e]))
- break;
+ if (!gen8_ppgtt_clear_pdp(vm, pdp, start, length))
+ continue;
- if (gen8_ppgtt_clear_pdp(vm, pdp, start, length)) {
- __clear_bit(pml4e, pml4->used_pml4es);
- gen8_ppgtt_set_pml4e(pml4, vm->scratch_pdp, pml4e);
- free_pdp(vm, pdp);
- }
+ gen8_ppgtt_set_pml4e(pml4, vm->scratch_pdp, pml4e);
+ __clear_bit(pml4e, pml4->used_pml4es);
+
+ free_pdp(vm, pdp);
}
}
@@ -1017,7 +1003,7 @@ static void gen8_ppgtt_cleanup_3lvl(struct i915_address_space *vm,
{
int i;
- for_each_set_bit(i, pdp->used_pdpes, I915_PDPES_PER_PDP(vm->i915)) {
+ for (i = 0; i < I915_PDPES_PER_PDP(vm->i915); i++) {
if (pdp->page_directory[i] == vm->scratch_pd)
continue;
@@ -1088,65 +1074,6 @@ static int gen8_ppgtt_alloc_pd(struct i915_address_space *vm,
}
/**
- * gen8_ppgtt_alloc_page_directories() - Allocate page directories for VA range.
- * @vm: Master vm structure.
- * @pdp: Page directory pointer for this address range.
- * @start: Starting virtual address to begin allocations.
- * @length: Size of the allocations.
- * @new_pds: Bitmap set by function with new allocations. Likely used by the
- * caller to free on error.
- *
- * Allocate the required number of page directories starting at the pde index of
- * @start, and ending at the pde index @start + @length. This function will skip
- * over already allocated page directories within the range, and only allocate
- * new ones, setting the appropriate pointer within the pdp as well as the
- * correct position in the bitmap @new_pds.
- *
- * The function will only allocate the pages within the range for a give page
- * directory pointer. In other words, if @start + @length straddles a virtually
- * addressed PDP boundary (512GB for 4k pages), there will be more allocations
- * required by the caller, This is not currently possible, and the BUG in the
- * code will prevent it.
- *
- * Return: 0 if success; negative error code otherwise.
- */
-static int
-gen8_ppgtt_alloc_page_directories(struct i915_address_space *vm,
- struct i915_page_directory_pointer *pdp,
- uint64_t start,
- uint64_t length,
- unsigned long *new_pds)
-{
- struct i915_page_directory *pd;
- uint32_t pdpe;
- uint32_t pdpes = I915_PDPES_PER_PDP(dev_priv);
-
- WARN_ON(!bitmap_empty(new_pds, pdpes));
-
- gen8_for_each_pdpe(pd, pdp, start, length, pdpe) {
- if (test_bit(pdpe, pdp->used_pdpes))
- continue;
-
- pd = alloc_pd(vm);
- if (IS_ERR(pd))
- goto unwind_out;
-
- gen8_initialize_pd(vm, pd);
- pdp->page_directory[pdpe] = pd;
- __set_bit(pdpe, new_pds);
- trace_i915_page_directory_entry_alloc(vm, pdpe, start, GEN8_PDPE_SHIFT);
- }
-
- return 0;
-
-unwind_out:
- for_each_set_bit(pdpe, new_pds, pdpes)
- free_pd(vm, pdp->page_directory[pdpe]);
-
- return -ENOMEM;
-}
-
-/**
* gen8_ppgtt_alloc_page_dirpointers() - Allocate pdps for VA range.
* @vm: Master vm structure.
* @pml4: Page map level 4 for this address range.
@@ -1166,23 +1093,19 @@ static int
gen8_ppgtt_alloc_page_dirpointers(struct i915_address_space *vm,
struct i915_pml4 *pml4,
uint64_t start,
- uint64_t length,
- unsigned long *new_pdps)
+ uint64_t length)
{
struct i915_page_directory_pointer *pdp;
uint32_t pml4e;
- WARN_ON(!bitmap_empty(new_pdps, GEN8_PML4ES_PER_PML4));
-
gen8_for_each_pml4e(pdp, pml4, start, length, pml4e) {
if (!test_bit(pml4e, pml4->used_pml4es)) {
pdp = alloc_pdp(vm);
if (IS_ERR(pdp))
- goto unwind_out;
+ return PTR_ERR(pdp);
gen8_initialize_pdp(vm, pdp);
pml4->pdps[pml4e] = pdp;
- __set_bit(pml4e, new_pdps);
trace_i915_page_directory_pointer_entry_alloc(vm,
pml4e,
start,
@@ -1191,34 +1114,6 @@ gen8_ppgtt_alloc_page_dirpointers(struct i915_address_space *vm,
}
return 0;
-
-unwind_out:
- for_each_set_bit(pml4e, new_pdps, GEN8_PML4ES_PER_PML4)
- free_pdp(vm, pml4->pdps[pml4e]);
-
- return -ENOMEM;
-}
-
-static void
-free_gen8_temp_bitmaps(unsigned long *new_pds)
-{
- kfree(new_pds);
-}
-
-/* Fills in the page directory bitmap, and the array of page tables bitmap. Both
- * of these are based on the number of PDPEs in the system.
- */
-static int __must_check
-alloc_gen8_temp_bitmaps(unsigned long **new_pds, uint32_t pdpes)
-{
- unsigned long *pds;
-
- pds = kcalloc(BITS_TO_LONGS(pdpes), sizeof(unsigned long), GFP_TEMPORARY);
- if (!pds)
- return -ENOMEM;
-
- *new_pds = pds;
- return 0;
}
static int gen8_alloc_va_range_3lvl(struct i915_address_space *vm,
@@ -1227,47 +1122,37 @@ static int gen8_alloc_va_range_3lvl(struct i915_address_space *vm,
uint64_t length)
{
struct i915_hw_ppgtt *ppgtt = i915_vm_to_ppgtt(vm);
- unsigned long *new_page_dirs;
struct i915_page_directory *pd;
- uint32_t pdpe;
- uint32_t pdpes = I915_PDPES_PER_PDP(dev_priv);
+ u64 from = start;
+ unsigned int pdpe;
int ret;
- ret = alloc_gen8_temp_bitmaps(&new_page_dirs, pdpes);
- if (ret)
- return ret;
-
- /* Do the allocations first so we can easily bail out */
- ret = gen8_ppgtt_alloc_page_directories(vm, pdp, start, length,
- new_page_dirs);
- if (ret) {
- free_gen8_temp_bitmaps(new_page_dirs);
- return ret;
- }
-
- /* For every page directory referenced, allocate page tables */
gen8_for_each_pdpe(pd, pdp, start, length, pdpe) {
- ret = gen8_ppgtt_alloc_pd(vm, pd, start, length);
- if (ret)
- goto err_out;
+ if (pd == vm->scratch_pd) {
+ pd = alloc_pd(vm);
+ if (IS_ERR(pd))
+ goto unwind;
- if (test_and_set_bit(pdpe, pdp->used_pdpes))
+ gen8_initialize_pd(vm, pd);
gen8_ppgtt_set_pdpe(vm, pdp, pd, pdpe);
+ pdp->used_pdpes++;
+ }
+
+ ret = gen8_ppgtt_alloc_pd(vm, pd, start, length);
+ if (unlikely(ret)) {
+ gen8_ppgtt_set_pdpe(vm, pdp, vm->scratch_pd, pdpe);
+ pdp->used_pdpes--;
+ free_pd(vm, pd);
+ goto unwind;
+ }
}
- /* Allocations have completed successfully, so set the bitmaps, and do
- * the mappings. */
- free_gen8_temp_bitmaps(new_page_dirs);
mark_tlbs_dirty(ppgtt);
return 0;
-err_out:
- for_each_set_bit(pdpe, new_page_dirs, pdpes)
- free_pd(vm, pdp->page_directory[pdpe]);
-
- free_gen8_temp_bitmaps(new_page_dirs);
- mark_tlbs_dirty(ppgtt);
- return ret;
+unwind:
+ gen8_ppgtt_clear_pdp(vm, pdp, from, start - from);
+ return -ENOMEM;
}
static int gen8_alloc_va_range_4lvl(struct i915_address_space *vm,
@@ -1287,8 +1172,7 @@ static int gen8_alloc_va_range_4lvl(struct i915_address_space *vm,
/* The pagedirectory and pagetable allocations are done in the shared 3
* and 4 level code. Just allocate the pdps.
*/
- ret = gen8_ppgtt_alloc_page_dirpointers(vm, pml4, start, length,
- new_pdps);
+ ret = gen8_ppgtt_alloc_page_dirpointers(vm, pml4, start, length);
if (ret)
return ret;
@@ -1340,7 +1224,7 @@ static void gen8_dump_pdp(struct i915_hw_ppgtt *ppgtt,
uint64_t pd_start = start;
uint32_t pde;
- if (!test_bit(pdpe, pdp->used_pdpes))
+ if (pdp->page_directory[pdpe] == ppgtt->base.scratch_pd)
continue;
seq_printf(m, "\tPDPE #%d\n", pdpe);
@@ -1407,29 +1291,34 @@ static void gen8_dump_ppgtt(struct i915_hw_ppgtt *ppgtt, struct seq_file *m)
static int gen8_preallocate_top_level_pdps(struct i915_hw_ppgtt *ppgtt)
{
- unsigned long *new_page_dirs;
- uint32_t pdpes = I915_PDPES_PER_PDP(to_i915(ppgtt->base.dev));
- int ret;
+ struct i915_address_space *vm = &ppgtt->base;
+ struct i915_page_directory_pointer *pdp = &ppgtt->pdp;
+ struct i915_page_directory *pd;
+ u64 start = 0, length = ppgtt->base.total;
+ u64 from = start;
+ unsigned int pdpe;
- /* We allocate temp bitmap for page tables for no gain
- * but as this is for init only, lets keep the things simple
- */
- ret = alloc_gen8_temp_bitmaps(&new_page_dirs, pdpes);
- if (ret)
- return ret;
+ gen8_for_each_pdpe(pd, pdp, start, length, pdpe) {
+ pd = alloc_pd(vm);
+ if (IS_ERR(pd))
+ goto unwind;
- /* Allocate for all pdps regardless of how the ppgtt
- * was defined.
- */
- ret = gen8_ppgtt_alloc_page_directories(&ppgtt->base, &ppgtt->pdp,
- 0, 1ULL << 32,
- new_page_dirs);
- if (!ret)
- *ppgtt->pdp.used_pdpes = *new_page_dirs;
+ gen8_initialize_pd(vm, pd);
+ gen8_ppgtt_set_pdpe(vm, pdp, pd, pdpe);
+ pdp->used_pdpes++;
+ }
- free_gen8_temp_bitmaps(new_page_dirs);
+ pdp->used_pdpes++; /* never remove */
+ return 0;
- return ret;
+unwind:
+ start -= from;
+ gen8_for_each_pdpe(pd, pdp, from, start, pdpe) {
+ gen8_ppgtt_set_pdpe(vm, pdp, vm->scratch_pd, pdpe);
+ free_pd(vm, pd);
+ }
+ pdp->used_pdpes = 0;
+ return -ENOMEM;
}
/*
@@ -1486,8 +1375,10 @@ static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
if (intel_vgpu_active(dev_priv)) {
ret = gen8_preallocate_top_level_pdps(ppgtt);
- if (ret)
+ if (ret) {
+ __pdp_fini(&ppgtt->pdp);
goto free_scratch;
+ }
}
ppgtt->base.insert_entries = gen8_ppgtt_insert_3lvl;
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 72656cc5ecf1..063e062fad2b 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -231,9 +231,8 @@ struct i915_page_directory {
struct i915_page_directory_pointer {
struct i915_page_dma base;
-
- unsigned long *used_pdpes;
struct i915_page_directory **page_directory;
+ unsigned int used_pdpes;
};
struct i915_pml4 {
--
2.11.0
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