create a pot-sized mm, then allocate one of each possible order within. This should leave the mm with exactly one page left.
v2: - removed unnecessary test succeeded print - replace list_del()/list_add_tail() with list_move_tail() Signed-off-by: Arunpravin <arunpravin.paneersel...@amd.com> Reviewed-by: Matthew Auld <matthew.a...@intel.com> Acked-by: Christian König <christian.koe...@amd.com> --- .../gpu/drm/selftests/drm_buddy_selftests.h | 1 + drivers/gpu/drm/selftests/test-drm_buddy.c | 147 ++++++++++++++++++ 2 files changed, 148 insertions(+) diff --git a/drivers/gpu/drm/selftests/drm_buddy_selftests.h b/drivers/gpu/drm/selftests/drm_buddy_selftests.h index 21a6bd38864f..b14f04a1de19 100644 --- a/drivers/gpu/drm/selftests/drm_buddy_selftests.h +++ b/drivers/gpu/drm/selftests/drm_buddy_selftests.h @@ -10,3 +10,4 @@ selftest(sanitycheck, igt_sanitycheck) /* keep first (selfcheck for igt) */ selftest(buddy_alloc_limit, igt_buddy_alloc_limit) selftest(buddy_alloc_range, igt_buddy_alloc_range) selftest(buddy_alloc_optimistic, igt_buddy_alloc_optimistic) +selftest(buddy_alloc_pessimistic, igt_buddy_alloc_pessimistic) diff --git a/drivers/gpu/drm/selftests/test-drm_buddy.c b/drivers/gpu/drm/selftests/test-drm_buddy.c index f20d3ad1ac65..2496113c4868 100644 --- a/drivers/gpu/drm/selftests/test-drm_buddy.c +++ b/drivers/gpu/drm/selftests/test-drm_buddy.c @@ -314,6 +314,153 @@ static void igt_mm_config(u64 *size, u64 *chunk_size) *size = (u64)s << 12; } +static int igt_buddy_alloc_pessimistic(void *arg) +{ + u64 mm_size, size, min_page_size, start = 0; + struct drm_buddy_block *block, *bn; + const unsigned int max_order = 16; + unsigned long flags = 0; + struct drm_buddy mm; + unsigned int order; + LIST_HEAD(blocks); + LIST_HEAD(tmp); + int err; + + /* + * Create a pot-sized mm, then allocate one of each possible + * order within. This should leave the mm with exactly one + * page left. + */ + + mm_size = PAGE_SIZE << max_order; + err = drm_buddy_init(&mm, mm_size, PAGE_SIZE); + if (err) { + pr_err("buddy_init failed(%d)\n", err); + return err; + } + BUG_ON(mm.max_order != max_order); + + for (order = 0; order < max_order; order++) { + size = min_page_size = get_size(order, PAGE_SIZE); + err = drm_buddy_alloc_blocks(&mm, start, mm_size, size, min_page_size, &tmp, flags); + if (err) { + pr_info("buddy_alloc hit -ENOMEM with order=%d\n", + order); + goto err; + } + + block = list_first_entry_or_null(&tmp, + struct drm_buddy_block, + link); + if (!block) { + pr_err("alloc_blocks has no blocks\n"); + err = -EINVAL; + goto err; + } + + list_move_tail(&block->link, &blocks); + } + + /* And now the last remaining block available */ + size = min_page_size = get_size(0, PAGE_SIZE); + err = drm_buddy_alloc_blocks(&mm, start, mm_size, size, min_page_size, &tmp, flags); + if (err) { + pr_info("buddy_alloc hit -ENOMEM on final alloc\n"); + goto err; + } + + block = list_first_entry_or_null(&tmp, + struct drm_buddy_block, + link); + if (!block) { + pr_err("alloc_blocks has no blocks\n"); + err = -EINVAL; + goto err; + } + + list_move_tail(&block->link, &blocks); + + /* Should be completely full! */ + for (order = max_order; order--; ) { + size = min_page_size = get_size(order, PAGE_SIZE); + err = drm_buddy_alloc_blocks(&mm, start, mm_size, size, min_page_size, &tmp, flags); + if (!err) { + pr_info("buddy_alloc unexpectedly succeeded at order %d, it should be full!", + order); + block = list_first_entry_or_null(&tmp, + struct drm_buddy_block, + link); + if (!block) { + pr_err("alloc_blocks has no blocks\n"); + err = -EINVAL; + goto err; + } + + list_move_tail(&block->link, &blocks); + err = -EINVAL; + goto err; + } + } + + block = list_last_entry(&blocks, typeof(*block), link); + list_del(&block->link); + drm_buddy_free_block(&mm, block); + + /* As we free in increasing size, we make available larger blocks */ + order = 1; + list_for_each_entry_safe(block, bn, &blocks, link) { + list_del(&block->link); + drm_buddy_free_block(&mm, block); + + size = min_page_size = get_size(order, PAGE_SIZE); + err = drm_buddy_alloc_blocks(&mm, start, mm_size, size, min_page_size, &tmp, flags); + if (err) { + pr_info("buddy_alloc (realloc) hit -ENOMEM with order=%d\n", + order); + goto err; + } + + block = list_first_entry_or_null(&tmp, + struct drm_buddy_block, + link); + if (!block) { + pr_err("alloc_blocks has no blocks\n"); + err = -EINVAL; + goto err; + } + + list_del(&block->link); + drm_buddy_free_block(&mm, block); + order++; + } + + /* To confirm, now the whole mm should be available */ + size = min_page_size = get_size(max_order, PAGE_SIZE); + err = drm_buddy_alloc_blocks(&mm, start, mm_size, size, min_page_size, &tmp, flags); + if (err) { + pr_info("buddy_alloc (realloc) hit -ENOMEM with order=%d\n", + max_order); + goto err; + } + + block = list_first_entry_or_null(&tmp, + struct drm_buddy_block, + link); + if (!block) { + pr_err("alloc_blocks has no blocks\n"); + err = -EINVAL; + goto err; + } + + list_del(&block->link); + drm_buddy_free_block(&mm, block); + +err: + drm_buddy_free_list(&mm, &blocks); + drm_buddy_fini(&mm); + return err; +} + static int igt_buddy_alloc_optimistic(void *arg) { u64 mm_size, size, min_page_size, start = 0; -- 2.25.1