Hi Am 01.12.21 um 17:39 schrieb Arunpravin:
- Make drm_buddy_alloc a single function to handle range allocation and non-range allocation demands - Implemented a new function alloc_range() which allocates the requested power-of-two block comply with range limitations - Moved order computation and memory alignment logic from i915 driver to drm buddy v2: merged below changes to keep the build unbroken - drm_buddy_alloc_range() becomes obsolete and may be removed - enable ttm range allocation (fpfn / lpfn) support in i915 driver - apply enhanced drm_buddy_alloc() function to i915 driver v3(Matthew Auld): - Fix alignment issues and remove unnecessary list_empty check - add more validation checks for input arguments - make alloc_range() block allocations as bottom-up - optimize order computation logic - replace uint64_t with u64, which is preferred in the kernel v4(Matthew Auld): - keep drm_buddy_alloc_range() function implementation for generic actual range allocations - keep alloc_range() implementation for end bias allocations Signed-off-by: Arunpravin <Arunpravin.PaneerSelvam@xxxxxxx> --- drivers/gpu/drm/drm_buddy.c | 316 +++++++++++++----- drivers/gpu/drm/i915/i915_ttm_buddy_manager.c | 67 ++-- drivers/gpu/drm/i915/i915_ttm_buddy_manager.h | 2 + include/drm/drm_buddy.h | 22 +- 4 files changed, 285 insertions(+), 122 deletions(-) diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c index 9340a4b61c5a..7f47632821f4 100644 --- a/drivers/gpu/drm/drm_buddy.c +++ b/drivers/gpu/drm/drm_buddy.c @@ -280,23 +280,97 @@ void drm_buddy_free_list(struct drm_buddy_mm *mm, struct list_head *objects) } EXPORT_SYMBOL(drm_buddy_free_list);-/**- * drm_buddy_alloc - allocate power-of-two blocks - * - * @mm: DRM buddy manager to allocate from - * @order: size of the allocation - * - * The order value here translates to: - * - * 0 = 2^0 * mm->chunk_size - * 1 = 2^1 * mm->chunk_size - * 2 = 2^2 * mm->chunk_size - * - * Returns: - * allocated ptr to the &drm_buddy_block on success - */ -struct drm_buddy_block * -drm_buddy_alloc(struct drm_buddy_mm *mm, unsigned int order) +static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) +{ + return s1 <= e2 && e1 >= s2; +} + +static inline bool contains(u64 s1, u64 e1, u64 s2, u64 e2) +{ + return s1 <= s2 && e1 >= e2; +} + +static struct drm_buddy_block * +alloc_range_bias(struct drm_buddy_mm *mm, + u64 start, u64 end, + unsigned int order) +{ + struct drm_buddy_block *block; + struct drm_buddy_block *buddy; + LIST_HEAD(dfs); + int err; + int i; + + end = end - 1; + + for (i = 0; i < mm->n_roots; ++i) + list_add_tail(&mm->roots[i]->tmp_link, &dfs); + + do { + u64 block_start; + u64 block_end; + + block = list_first_entry_or_null(&dfs, + struct drm_buddy_block, + tmp_link); + if (!block) + break; + + list_del(&block->tmp_link); + + if (drm_buddy_block_order(block) < order) + continue; + + block_start = drm_buddy_block_offset(block); + block_end = block_start + drm_buddy_block_size(mm, block) - 1; + + if (!overlaps(start, end, block_start, block_end)) + continue; + + if (drm_buddy_block_is_allocated(block)) + continue; + + if (contains(start, end, block_start, block_end) && + order == drm_buddy_block_order(block)) { + /* + * Find the free block within the range. + */ + if (drm_buddy_block_is_free(block)) + return block; + + continue; + } + + if (!drm_buddy_block_is_split(block)) { + err = split_block(mm, block); + if (unlikely(err)) + goto err_undo; + } + + list_add(&block->right->tmp_link, &dfs); + list_add(&block->left->tmp_link, &dfs); + } while (1); + + return ERR_PTR(-ENOSPC); + +err_undo: + /* + * We really don't want to leave around a bunch of split blocks, since + * bigger is better, so make sure we merge everything back before we + * free the allocated blocks. + */ + buddy = get_buddy(block); + if (buddy && + (drm_buddy_block_is_free(block) && + drm_buddy_block_is_free(buddy))) + __drm_buddy_free(mm, block); + return ERR_PTR(err); +} + +static struct drm_buddy_block * +alloc_from_freelist(struct drm_buddy_mm *mm, + unsigned int order, + unsigned long flags) { struct drm_buddy_block *block = NULL; unsigned int i; @@ -318,78 +392,28 @@ drm_buddy_alloc(struct drm_buddy_mm *mm, unsigned int order) while (i != order) { err = split_block(mm, block); if (unlikely(err)) - goto out_free; + goto err_undo;- /* Go low */- block = block->left; + block = block->right; i--; } - - mark_allocated(block); - mm->avail -= drm_buddy_block_size(mm, block); - kmemleak_update_trace(block); return block;-out_free:+err_undo: if (i != order) __drm_buddy_free(mm, block); return ERR_PTR(err); } -EXPORT_SYMBOL(drm_buddy_alloc); - -static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) -{ - return s1 <= e2 && e1 >= s2; -}-static inline bool contains(u64 s1, u64 e1, u64 s2, u64 e2)-{ - return s1 <= s2 && e1 >= e2; -} - -/** - * drm_buddy_alloc_range - allocate range - * - * @mm: DRM buddy manager to allocate from - * @blocks: output list head to add allocated blocks - * @start: start of the allowed range for this block - * @size: size of the allocation - * - * Intended for pre-allocating portions of the address space, for example to - * reserve a block for the initial framebuffer or similar, hence the expectation - * here is that drm_buddy_alloc() is still the main vehicle for - * allocations, so if that's not the case then the drm_mm range allocator is - * probably a much better fit, and so you should probably go use that instead. - * - * Note that it's safe to chain together multiple alloc_ranges - * with the same blocks list - * - * Returns: - * 0 on success, error code on failure. - */ -int drm_buddy_alloc_range(struct drm_buddy_mm *mm, - struct list_head *blocks, - u64 start, u64 size) +static int __alloc_range(struct drm_buddy_mm *mm, + struct list_head *dfs, + u64 start, u64 size, + struct list_head *blocks) { struct drm_buddy_block *block; struct drm_buddy_block *buddy; - LIST_HEAD(allocated); - LIST_HEAD(dfs); u64 end; int err; - int i; - - if (size < mm->chunk_size) - return -EINVAL; - - if (!IS_ALIGNED(size | start, mm->chunk_size)) - return -EINVAL; - - if (range_overflows(start, size, mm->size)) - return -EINVAL; - - for (i = 0; i < mm->n_roots; ++i) - list_add_tail(&mm->roots[i]->tmp_link, &dfs);end = start + size - 1; @@ -397,7 +421,7 @@ int drm_buddy_alloc_range(struct drm_buddy_mm *mm,u64 block_start; u64 block_end;- block = list_first_entry_or_null(&dfs,+ block = list_first_entry_or_null(dfs, struct drm_buddy_block, tmp_link); if (!block) @@ -424,7 +448,7 @@ int drm_buddy_alloc_range(struct drm_buddy_mm *mm,mark_allocated(block);mm->avail -= drm_buddy_block_size(mm, block); - list_add_tail(&block->link, &allocated); + list_add_tail(&block->link, blocks); continue; }@@ -434,11 +458,10 @@ int drm_buddy_alloc_range(struct drm_buddy_mm *mm,goto err_undo; }- list_add(&block->right->tmp_link, &dfs);- list_add(&block->left->tmp_link, &dfs); + list_add(&block->right->tmp_link, dfs); + list_add(&block->left->tmp_link, dfs); } while (1);- list_splice_tail(&allocated, blocks);return 0;err_undo:@@ -453,11 +476,144 @@ int drm_buddy_alloc_range(struct drm_buddy_mm *mm, drm_buddy_block_is_free(buddy))) __drm_buddy_free(mm, block);+err_free:+ drm_buddy_free_list(mm, blocks); + return err; +} + +/** + * __drm_buddy_alloc_range - actual range allocation + * + * @mm: DRM buddy manager to allocate from + * @start: start of the allowed range for this block + * @size: size of the allocation + * @blocks: output list head to add allocated blocks + * + * Intended for pre-allocating portions of the address space, for example to + * reserve a block for the initial framebuffer or similar + * + * Note that it's safe to chain together multiple alloc_ranges + * with the same blocks list + * + * Returns: + * 0 on success, error code on failure. + */ +static int __drm_buddy_alloc_range(struct drm_buddy_mm *mm, + u64 start, + u64 size, + struct list_head *blocks) +{ + LIST_HEAD(dfs); + int i; + + for (i = 0; i < mm->n_roots; ++i) + list_add_tail(&mm->roots[i]->tmp_link, &dfs); + + return __alloc_range(mm, &dfs, start, size, blocks); +} + +/** + * drm_buddy_alloc - allocate power-of-two blocks + * + * @mm: DRM buddy manager to allocate from + * @start: start of the allowed range for this block + * @end: end of the allowed range for this block + * @size: size of the allocation + * @min_page_size: alignment of the allocation + * @blocks: output list head to add allocated blocks + * @flags: DRM_BUDDY_*_ALLOCATION flags + * + * alloc_range_bias() called on range limitations, which traverses + * the tree and returns the desired block. + * + * alloc_from_freelist() called when *no* range restrictions + * are enforced, which picks the block from the freelist. + * + * blocks are allocated in order, the order value here translates to: + * + * 0 = 2^0 * mm->chunk_size + * 1 = 2^1 * mm->chunk_size + * 2 = 2^2 * mm->chunk_size + * + * Returns: + * 0 on success, error code on failure. + */ +int drm_buddy_alloc(struct drm_buddy_mm *mm, + u64 start, u64 end, u64 size, + u64 min_page_size, + struct list_head *blocks, + unsigned long flags) +{ + struct drm_buddy_block *block = NULL; + unsigned int min_order, order; + unsigned long pages; + LIST_HEAD(allocated); + int err; + + if (size < mm->chunk_size) + return -EINVAL; + + if (min_page_size < mm->chunk_size) + return -EINVAL; + + if (!is_power_of_2(min_page_size)) + return -EINVAL; + + if (!IS_ALIGNED(start | end | size, mm->chunk_size)) + return -EINVAL; + + if (check_range_overflow(start, end, size, mm->size)) + return -EINVAL; + + /* Actual range allocation */ + if (start + size == end) + return __drm_buddy_alloc_range(mm, start, size, blocks); + + pages = size >> ilog2(mm->chunk_size); + order = fls(pages) - 1; + min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); + + do { + order = min(order, (unsigned int)fls(pages) - 1); + BUG_ON(order > mm->max_order); + BUG_ON(order < min_order); + + do { + if (flags & DRM_BUDDY_RANGE_ALLOCATION) + /* Allocate traversing within the range */ + block = alloc_range_bias(mm, start, end, order); + else + /* Allocate from freelist */ + block = alloc_from_freelist(mm, order, flags); + + if (!IS_ERR(block)) + break; + + if (order-- == min_order) { + err = -ENOSPC; + goto err_free; + } + } while (1); + + mark_allocated(block); + mm->avail -= drm_buddy_block_size(mm, block); + kmemleak_update_trace(block); + list_add_tail(&block->link, &allocated); + + pages -= BIT(order); + + if (!pages) + break; + } while (1); + + list_splice_tail(&allocated, blocks); + return 0; + err_free: drm_buddy_free_list(mm, &allocated); return err; } -EXPORT_SYMBOL(drm_buddy_alloc_range); +EXPORT_SYMBOL(drm_buddy_alloc);/*** drm_buddy_block_print - print block information diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c index c4b70cb8c248..7621d42155e6 100644 --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c @@ -36,13 +36,14 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, struct i915_ttm_buddy_manager *bman = to_buddy_manager(man); struct i915_ttm_buddy_resource *bman_res; struct drm_buddy_mm *mm = &bman->mm; - unsigned long n_pages; - unsigned int min_order; + unsigned long n_pages, lpfn; u64 min_page_size; u64 size; int err;- GEM_BUG_ON(place->fpfn || place->lpfn);+ lpfn = place->lpfn; + if (!lpfn) + lpfn = man->size;bman_res = kzalloc(sizeof(*bman_res), GFP_KERNEL);if (!bman_res) @@ -52,6 +53,9 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man, INIT_LIST_HEAD(&bman_res->blocks); bman_res->mm = mm;+ if (place->fpfn || lpfn != man->size)+ bman_res->flags |= DRM_BUDDY_RANGE_ALLOCATION; + GEM_BUG_ON(!bman_res->base.num_pages); size = bman_res->base.num_pages << PAGE_SHIFT;@@ -60,10 +64,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man,min_page_size = bo->page_alignment << PAGE_SHIFT;GEM_BUG_ON(min_page_size < mm->chunk_size);- min_order = ilog2(min_page_size) - ilog2(mm->chunk_size); + if (place->flags & TTM_PL_FLAG_CONTIGUOUS) { + unsigned long pages; + size = roundup_pow_of_two(size); - min_order = ilog2(size) - ilog2(mm->chunk_size); + min_page_size = size; + + pages = size >> ilog2(mm->chunk_size); + if (pages > lpfn) + lpfn = pages; }if (size > mm->size) {@@ -73,34 +83,16 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man,n_pages = size >> ilog2(mm->chunk_size); - do {- struct drm_buddy_block *block; - unsigned int order; - - order = fls(n_pages) - 1; - GEM_BUG_ON(order > mm->max_order); - GEM_BUG_ON(order < min_order); - - do { - mutex_lock(&bman->lock); - block = drm_buddy_alloc(mm, order); - mutex_unlock(&bman->lock); - if (!IS_ERR(block)) - break; - - if (order-- == min_order) { - err = -ENOSPC; - goto err_free_blocks; - } - } while (1); - - n_pages -= BIT(order); - - list_add_tail(&block->link, &bman_res->blocks); - - if (!n_pages) - break; - } while (1); + mutex_lock(&bman->lock); + err = drm_buddy_alloc(mm, (u64)place->fpfn << PAGE_SHIFT, + (u64)place->lpfn << PAGE_SHIFT, + (u64)n_pages << PAGE_SHIFT, + min_page_size, + &bman_res->blocks, + bman_res->flags); + mutex_unlock(&bman->lock); + if (unlikely(err)) + goto err_free_blocks;*res = &bman_res->base;return 0; @@ -266,10 +258,17 @@ int i915_ttm_buddy_man_reserve(struct ttm_resource_manager *man, { struct i915_ttm_buddy_manager *bman = to_buddy_manager(man); struct drm_buddy_mm *mm = &bman->mm; + unsigned long flags = 0; int ret;+ flags |= DRM_BUDDY_RANGE_ALLOCATION;+ mutex_lock(&bman->lock); - ret = drm_buddy_alloc_range(mm, &bman->reserved, start, size); + ret = drm_buddy_alloc(mm, start, + start + size, + size, mm->chunk_size, + &bman->reserved, + flags); mutex_unlock(&bman->lock);return ret;diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h index fa644b512c2e..5ba490875f66 100644 --- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h +++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.h @@ -20,6 +20,7 @@ struct drm_buddy_mm; * * @base: struct ttm_resource base class we extend * @blocks: the list of struct i915_buddy_block for this resource/allocation + * @flags: DRM_BUDDY_*_ALLOCATION flags * @mm: the struct i915_buddy_mm for this resource * * Extends the struct ttm_resource to manage an address space allocation with @@ -28,6 +29,7 @@ struct drm_buddy_mm; struct i915_ttm_buddy_resource { struct ttm_resource base; struct list_head blocks; + unsigned long flags; struct drm_buddy_mm *mm; };diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.hindex f9ff48a3f3a6..221de702e909 100644 --- a/include/drm/drm_buddy.h +++ b/include/drm/drm_buddy.h @@ -13,15 +13,22 @@#include <drm/drm_print.h> -#define range_overflows(start, size, max) ({ \+#define check_range_overflow(start, end, size, max) ({ \ typeof(start) start__ = (start); \ + typeof(end) end__ = (end);\ typeof(size) size__ = (size); \ typeof(max) max__ = (max); \ (void)(&start__ == &size__); \ (void)(&start__ == &max__); \ - start__ >= max__ || size__ > max__ - start__; \ + (void)(&start__ == &end__); \ + (void)(&end__ == &size__); \ + (void)(&end__ == &max__); \ + start__ >= max__ || end__ > max__ || \ + size__ > end__ - start__; \ })+#define DRM_BUDDY_RANGE_ALLOCATION (1 << 0)+ struct drm_buddy_block { #define DRM_BUDDY_HEADER_OFFSET GENMASK_ULL(63, 12) #define DRM_BUDDY_HEADER_STATE GENMASK_ULL(11, 10) @@ -132,12 +139,11 @@ int drm_buddy_init(struct drm_buddy_mm *mm, u64 size, u64 chunk_size);void drm_buddy_fini(struct drm_buddy_mm *mm); -struct drm_buddy_block *-drm_buddy_alloc(struct drm_buddy_mm *mm, unsigned int order);
Just a style issue. The structure is called drm_buddy_mm. For consistency, I like to suggest to name all the public interfaces and defines drm_buddy_mm_* instead of just drm_buddy_*.
- -int drm_buddy_alloc_range(struct drm_buddy_mm *mm, - struct list_head *blocks, - u64 start, u64 size); +int drm_buddy_alloc(struct drm_buddy_mm *mm, + u64 start, u64 end, u64 size, + u64 min_page_size, + struct list_head *blocks, + unsigned long flags);void drm_buddy_free(struct drm_buddy_mm *mm, struct drm_buddy_block *block);
I'd call those *_alloc_blocks() and _free_blocks(). Right now it sounds as if they allocate and free instances of drm_buddy_mm.
Best regards Thomas
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Ivo Totev
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