From: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> Add a unit test to verify that we can iterate over multi-order entries properly via a radix_tree_for_each_slot() loop. This was done with a single, somewhat complicated configuration that was meant to test many of the various corner cases having to do with multi-order entries: - An iteration could begin at a sibling entry, and we need to return the canonical entry. - We could have entries of various orders in the same slots[] array. - We could have multi-order entries at a nonzero height, followed by indirect pointers to more radix tree nodes later in that same slots[] array. Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx> Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx> --- tools/testing/radix-tree/multiorder.c | 92 +++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) diff --git a/tools/testing/radix-tree/multiorder.c b/tools/testing/radix-tree/multiorder.c index 606bfe04b104..583c5127fbcf 100644 --- a/tools/testing/radix-tree/multiorder.c +++ b/tools/testing/radix-tree/multiorder.c @@ -57,6 +57,96 @@ static void multiorder_insert_bug(void) item_kill_tree(&tree); } +void multiorder_iteration(void) +{ + RADIX_TREE(tree, GFP_KERNEL); + struct radix_tree_iter iter; + void **slot; + int i, err; + + printf("Multiorder iteration test\n"); + +#define NUM_ENTRIES 11 + int index[NUM_ENTRIES] = {0, 2, 4, 8, 16, 32, 34, 36, 64, 72, 128}; + int order[NUM_ENTRIES] = {1, 1, 2, 3, 4, 1, 0, 1, 3, 0, 7}; + + for (i = 0; i < NUM_ENTRIES; i++) { + err = item_insert_order(&tree, index[i], order[i]); + assert(!err); + } + + i = 0; + /* start from index 1 to verify we find the multi-order entry at 0 */ + radix_tree_for_each_slot(slot, &tree, &iter, 1) { + int height = order[i] / RADIX_TREE_MAP_SHIFT; + int shift = height * RADIX_TREE_MAP_SHIFT; + + assert(iter.index == index[i]); + assert(iter.shift == shift); + i++; + } + + /* + * Now iterate through the tree starting at an elevated multi-order + * entry, beginning at an index in the middle of the range. + */ + i = 8; + radix_tree_for_each_slot(slot, &tree, &iter, 70) { + int height = order[i] / RADIX_TREE_MAP_SHIFT; + int shift = height * RADIX_TREE_MAP_SHIFT; + + assert(iter.index == index[i]); + assert(iter.shift == shift); + i++; + } + + item_kill_tree(&tree); +} + +void multiorder_tagged_iteration(void) +{ + RADIX_TREE(tree, GFP_KERNEL); + struct radix_tree_iter iter; + void **slot; + int i; + + printf("Multiorder tagged iteration test\n"); + +#define MT_NUM_ENTRIES 9 + int index[MT_NUM_ENTRIES] = {0, 2, 4, 16, 32, 40, 64, 72, 128}; + int order[MT_NUM_ENTRIES] = {1, 0, 2, 4, 3, 1, 3, 0, 7}; + +#define TAG_ENTRIES 7 + int tag_index[TAG_ENTRIES] = {0, 4, 16, 40, 64, 72, 128}; + + for (i = 0; i < MT_NUM_ENTRIES; i++) + assert(!item_insert_order(&tree, index[i], order[i])); + + assert(!radix_tree_tagged(&tree, 1)); + + for (i = 0; i < TAG_ENTRIES; i++) + assert(radix_tree_tag_set(&tree, tag_index[i], 1)); + + i = 0; + /* start from index 1 to verify we find the multi-order entry at 0 */ + radix_tree_for_each_tagged(slot, &tree, &iter, 1, 1) { + assert(iter.index == tag_index[i]); + i++; + } + + /* + * Now iterate through the tree starting at an elevated multi-order + * entry, beginning at an index in the middle of the range. + */ + i = 4; + radix_tree_for_each_slot(slot, &tree, &iter, 70) { + assert(iter.index == tag_index[i]); + i++; + } + + item_kill_tree(&tree); +} + void multiorder_checks(void) { int i; @@ -67,5 +157,7 @@ void multiorder_checks(void) multiorder_check((1UL << i) + 1, i); } + multiorder_iteration(); + multiorder_tagged_iteration(); multiorder_insert_bug(); } -- 2.8.0.rc3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>