From: "Liam R. Howlett" Liam.Howlett@oracle.com
commit 24662decdd44645e8f027d7912be962dd461d1aa upstream.
Since the pivot being set is now reliable, the optimized loop no longer needs to find the node end. The redundant check for a dead node can also be avoided as there is no danger of using the wrong pivot since the results will be thrown out in the case of a dead node by the later check.
This patch also adds a benchmark test for the function to the maple tree test framework. The benchmark shows an average increase performance of 5.98% over 3 runs with this commit.
Link: https://lkml.kernel.org/r/20231101171629.3612299-12-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Liam.Howlett@oracle.com Cc: Peng Zhang zhangpeng.00@bytedance.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Yu Kuai yukuai3@huawei.com --- lib/maple_tree.c | 12 +++--------- lib/test_maple_tree.c | 21 +++++++++++++++++++++ 2 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/lib/maple_tree.c b/lib/maple_tree.c index 472aef7a3d5c..ad8bf3413889 100644 --- a/lib/maple_tree.c +++ b/lib/maple_tree.c @@ -3742,23 +3742,17 @@ static inline void *mtree_lookup_walk(struct ma_state *mas) enum maple_type type; void __rcu **slots; unsigned char end; - unsigned long max;
next = mas->node; - max = ULONG_MAX; do { - offset = 0; node = mte_to_node(next); type = mte_node_type(next); pivots = ma_pivots(node, type); - end = ma_data_end(node, type, pivots, max); - if (unlikely(ma_dead_node(node))) - goto dead_node; + end = mt_pivots[type]; + offset = 0; do { - if (pivots[offset] >= mas->index) { - max = pivots[offset]; + if (pivots[offset] >= mas->index) break; - } } while (++offset < end);
slots = ma_slots(node, type); diff --git a/lib/test_maple_tree.c b/lib/test_maple_tree.c index f9acc6ef0728..26991888da14 100644 --- a/lib/test_maple_tree.c +++ b/lib/test_maple_tree.c @@ -43,6 +43,7 @@ atomic_t maple_tree_tests_passed; /* #define BENCH_NODE_STORE */ /* #define BENCH_AWALK */ /* #define BENCH_WALK */ +/* #define BENCH_LOAD */ /* #define BENCH_MT_FOR_EACH */ /* #define BENCH_FORK */ /* #define BENCH_MAS_FOR_EACH */ @@ -1754,6 +1755,19 @@ static noinline void __init bench_walk(struct maple_tree *mt) } #endif
+#if defined(BENCH_LOAD) +static noinline void __init bench_load(struct maple_tree *mt) +{ + int i, max = 2500, count = 550000000; + + for (i = 0; i < max; i += 10) + mtree_store_range(mt, i, i + 5, xa_mk_value(i), GFP_KERNEL); + + for (i = 0; i < count; i++) + mtree_load(mt, 1470); +} +#endif + #if defined(BENCH_MT_FOR_EACH) static noinline void __init bench_mt_for_each(struct maple_tree *mt) { @@ -3620,6 +3634,13 @@ static int __init maple_tree_seed(void) mtree_destroy(&tree); goto skip; #endif +#if defined(BENCH_LOAD) +#define BENCH + mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE); + bench_load(&tree); + mtree_destroy(&tree); + goto skip; +#endif #if defined(BENCH_FORK) #define BENCH mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);