Commit d6e8d0dc authored by Peng Zhang's avatar Peng Zhang Committed by Andrew Morton
Browse files

maple_tree: add test for mas_wr_modify() fast path 

Patch series "Optimize the fast path of mas_store()", v4.

Add fast paths for mas_wr_append() and mas_wr_slot_store() respectively.
The newly added fast path of mas_wr_append() is used in fork() and how
much it benefits fork() depends on how many VMAs are duplicated.

Thanks Liam for the review.


This patch (of 4):

Add tests for all cases of mas_wr_append() and mas_wr_slot_store().

Link: https://lkml.kernel.org/r/20230628073657.75314-1-zhangpeng.00@bytedance.com
Link: https://lkml.kernel.org/r/20230628073657.75314-2-zhangpeng.00@bytedance.com


Signed-off-by: default avatarPeng Zhang <zhangpeng.00@bytedance.com>
Reviewed-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent f04d16ee

lib/test_maple_tree.c

+65 −0
Original line number Diff line number Diff line
@@ -1157,6 +1157,71 @@ static noinline void __init check_ranges(struct maple_tree *mt) 
	MT_BUG_ON(mt, !mt_height(mt));

	mtree_destroy(mt);



	/* Check in-place modifications */

	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);

	/* Append to the start of last range */

	mt_set_non_kernel(50);

	for (i = 0; i <= 500; i++) {

		val = i * 5 + 1;

		val2 = val + 4;

		check_store_range(mt, val, val2, xa_mk_value(val), 0);

	}



	/* Append to the last range without touching any boundaries */

	for (i = 0; i < 10; i++) {

		val = val2 + 5;

		val2 = val + 4;

		check_store_range(mt, val, val2, xa_mk_value(val), 0);

	}



	/* Append to the end of last range */

	val = val2;

	for (i = 0; i < 10; i++) {

		val += 5;

		MT_BUG_ON(mt, mtree_test_store_range(mt, val, ULONG_MAX,

						     xa_mk_value(val)) != 0);

	}



	/* Overwriting the range and over a part of the next range */

	for (i = 10; i < 30; i += 2) {

		val = i * 5 + 1;

		val2 = val + 5;

		check_store_range(mt, val, val2, xa_mk_value(val), 0);

	}



	/* Overwriting a part of the range and over the next range */

	for (i = 50; i < 70; i += 2) {

		val2 = i * 5;

		val = val2 - 5;

		check_store_range(mt, val, val2, xa_mk_value(val), 0);

	}



	/*

	 * Expand the range, only partially overwriting the previous and

	 * next ranges

	 */

	for (i = 100; i < 130; i += 3) {

		val = i * 5 - 5;

		val2 = i * 5 + 1;

		check_store_range(mt, val, val2, xa_mk_value(val), 0);

	}



	/*

	 * Expand the range, only partially overwriting the previous and

	 * next ranges, in RCU mode

	 */

	mt_set_in_rcu(mt);

	for (i = 150; i < 180; i += 3) {

		val = i * 5 - 5;

		val2 = i * 5 + 1;

		check_store_range(mt, val, val2, xa_mk_value(val), 0);

	}



	MT_BUG_ON(mt, !mt_height(mt));

	mt_validate(mt);

	mt_set_non_kernel(0);

	mtree_destroy(mt);



	/* Test rebalance gaps */

	mt_init_flags(mt, MT_FLAGS_ALLOC_RANGE);

	mt_set_non_kernel(50);