From: Davidlohr Bueso <dave@xxxxxxxxxxxx> Subject: lib/rbtree_test.c: support rb_root_cached We can work with a single rb_root_cached root to test both cached and non-cached rbtrees. In addition, also add a test to measure latencies between rb_first and its fast counterpart. Link: http://lkml.kernel.org/r/20170719014603.19029-7-dave@xxxxxxxxxxxx Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/rbtree_test.c | 156 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 137 insertions(+), 19 deletions(-) diff -puN lib/rbtree_test.c~lib-rbtree_testc-support-rb_root_cached lib/rbtree_test.c --- a/lib/rbtree_test.c~lib-rbtree_testc-support-rb_root_cached +++ a/lib/rbtree_test.c @@ -23,14 +23,14 @@ struct test_node { u32 augmented; }; -static struct rb_root root = RB_ROOT; +static struct rb_root_cached root = RB_ROOT_CACHED; static struct test_node *nodes = NULL; static struct rnd_state rnd; -static void insert(struct test_node *node, struct rb_root *root) +static void insert(struct test_node *node, struct rb_root_cached *root) { - struct rb_node **new = &root->rb_node, *parent = NULL; + struct rb_node **new = &root->rb_root.rb_node, *parent = NULL; u32 key = node->key; while (*new) { @@ -42,14 +42,40 @@ static void insert(struct test_node *nod } rb_link_node(&node->rb, parent, new); - rb_insert_color(&node->rb, root); + rb_insert_color(&node->rb, &root->rb_root); } -static inline void erase(struct test_node *node, struct rb_root *root) +static void insert_cached(struct test_node *node, struct rb_root_cached *root) { - rb_erase(&node->rb, root); + struct rb_node **new = &root->rb_root.rb_node, *parent = NULL; + u32 key = node->key; + bool leftmost = true; + + while (*new) { + parent = *new; + if (key < rb_entry(parent, struct test_node, rb)->key) + new = &parent->rb_left; + else { + new = &parent->rb_right; + leftmost = false; + } + } + + rb_link_node(&node->rb, parent, new); + rb_insert_color_cached(&node->rb, root, leftmost); } +static inline void erase(struct test_node *node, struct rb_root_cached *root) +{ + rb_erase(&node->rb, &root->rb_root); +} + +static inline void erase_cached(struct test_node *node, struct rb_root_cached *root) +{ + rb_erase_cached(&node->rb, root); +} + + static inline u32 augment_recompute(struct test_node *node) { u32 max = node->val, child_augmented; @@ -71,9 +97,10 @@ static inline u32 augment_recompute(stru RB_DECLARE_CALLBACKS(static, augment_callbacks, struct test_node, rb, u32, augmented, augment_recompute) -static void insert_augmented(struct test_node *node, struct rb_root *root) +static void insert_augmented(struct test_node *node, + struct rb_root_cached *root) { - struct rb_node **new = &root->rb_node, *rb_parent = NULL; + struct rb_node **new = &root->rb_root.rb_node, *rb_parent = NULL; u32 key = node->key; u32 val = node->val; struct test_node *parent; @@ -91,12 +118,47 @@ static void insert_augmented(struct test node->augmented = val; rb_link_node(&node->rb, rb_parent, new); - rb_insert_augmented(&node->rb, root, &augment_callbacks); + rb_insert_augmented(&node->rb, &root->rb_root, &augment_callbacks); +} + +static void insert_augmented_cached(struct test_node *node, + struct rb_root_cached *root) +{ + struct rb_node **new = &root->rb_root.rb_node, *rb_parent = NULL; + u32 key = node->key; + u32 val = node->val; + struct test_node *parent; + bool leftmost = true; + + while (*new) { + rb_parent = *new; + parent = rb_entry(rb_parent, struct test_node, rb); + if (parent->augmented < val) + parent->augmented = val; + if (key < parent->key) + new = &parent->rb.rb_left; + else { + new = &parent->rb.rb_right; + leftmost = false; + } + } + + node->augmented = val; + rb_link_node(&node->rb, rb_parent, new); + rb_insert_augmented_cached(&node->rb, root, + leftmost, &augment_callbacks); +} + + +static void erase_augmented(struct test_node *node, struct rb_root_cached *root) +{ + rb_erase_augmented(&node->rb, &root->rb_root, &augment_callbacks); } -static void erase_augmented(struct test_node *node, struct rb_root *root) +static void erase_augmented_cached(struct test_node *node, + struct rb_root_cached *root) { - rb_erase_augmented(&node->rb, root, &augment_callbacks); + rb_erase_augmented_cached(&node->rb, root, &augment_callbacks); } static void init(void) @@ -125,7 +187,7 @@ static void check_postorder_foreach(int { struct test_node *cur, *n; int count = 0; - rbtree_postorder_for_each_entry_safe(cur, n, &root, rb) + rbtree_postorder_for_each_entry_safe(cur, n, &root.rb_root, rb) count++; WARN_ON_ONCE(count != nr_nodes); @@ -135,7 +197,7 @@ static void check_postorder(int nr_nodes { struct rb_node *rb; int count = 0; - for (rb = rb_first_postorder(&root); rb; rb = rb_next_postorder(rb)) + for (rb = rb_first_postorder(&root.rb_root); rb; rb = rb_next_postorder(rb)) count++; WARN_ON_ONCE(count != nr_nodes); @@ -147,7 +209,7 @@ static void check(int nr_nodes) int count = 0, blacks = 0; u32 prev_key = 0; - for (rb = rb_first(&root); rb; rb = rb_next(rb)) { + for (rb = rb_first(&root.rb_root); rb; rb = rb_next(rb)) { struct test_node *node = rb_entry(rb, struct test_node, rb); WARN_ON_ONCE(node->key < prev_key); WARN_ON_ONCE(is_red(rb) && @@ -162,7 +224,7 @@ static void check(int nr_nodes) } WARN_ON_ONCE(count != nr_nodes); - WARN_ON_ONCE(count < (1 << black_path_count(rb_last(&root))) - 1); + WARN_ON_ONCE(count < (1 << black_path_count(rb_last(&root.rb_root))) - 1); check_postorder(nr_nodes); check_postorder_foreach(nr_nodes); @@ -173,7 +235,7 @@ static void check_augmented(int nr_nodes struct rb_node *rb; check(nr_nodes); - for (rb = rb_first(&root); rb; rb = rb_next(rb)) { + for (rb = rb_first(&root.rb_root); rb; rb = rb_next(rb)) { struct test_node *node = rb_entry(rb, struct test_node, rb); WARN_ON_ONCE(node->augmented != augment_recompute(node)); } @@ -207,7 +269,24 @@ static int __init rbtree_test_init(void) time = time2 - time1; time = div_u64(time, perf_loops); - printk(" -> test 1 (latency of nnodes insert+delete): %llu cycles\n", (unsigned long long)time); + printk(" -> test 1 (latency of nnodes insert+delete): %llu cycles\n", + (unsigned long long)time); + + time1 = get_cycles(); + + for (i = 0; i < perf_loops; i++) { + for (j = 0; j < nnodes; j++) + insert_cached(nodes + j, &root); + for (j = 0; j < nnodes; j++) + erase_cached(nodes + j, &root); + } + + time2 = get_cycles(); + time = time2 - time1; + + time = div_u64(time, perf_loops); + printk(" -> test 2 (latency of nnodes cached insert+delete): %llu cycles\n", + (unsigned long long)time); for (i = 0; i < nnodes; i++) insert(nodes + i, &root); @@ -215,7 +294,7 @@ static int __init rbtree_test_init(void) time1 = get_cycles(); for (i = 0; i < perf_loops; i++) { - for (node = rb_first(&root); node; node = rb_next(node)) + for (node = rb_first(&root.rb_root); node; node = rb_next(node)) ; } @@ -223,7 +302,31 @@ static int __init rbtree_test_init(void) time = time2 - time1; time = div_u64(time, perf_loops); - printk(" -> test 2 (latency of inorder traversal): %llu cycles\n", (unsigned long long)time); + printk(" -> test 3 (latency of inorder traversal): %llu cycles\n", + (unsigned long long)time); + + time1 = get_cycles(); + + for (i = 0; i < perf_loops; i++) + node = rb_first(&root.rb_root); + + time2 = get_cycles(); + time = time2 - time1; + + time = div_u64(time, perf_loops); + printk(" -> test 4 (latency to fetch first node)\n"); + printk(" non-cached: %llu cycles\n", (unsigned long long)time); + + time1 = get_cycles(); + + for (i = 0; i < perf_loops; i++) + node = rb_first_cached(&root); + + time2 = get_cycles(); + time = time2 - time1; + + time = div_u64(time, perf_loops); + printk(" cached: %llu cycles\n", (unsigned long long)time); for (i = 0; i < nnodes; i++) erase(nodes + i, &root); @@ -261,6 +364,21 @@ static int __init rbtree_test_init(void) time = div_u64(time, perf_loops); printk(" -> test 1 (latency of nnodes insert+delete): %llu cycles\n", (unsigned long long)time); + time1 = get_cycles(); + + for (i = 0; i < perf_loops; i++) { + for (j = 0; j < nnodes; j++) + insert_augmented_cached(nodes + j, &root); + for (j = 0; j < nnodes; j++) + erase_augmented_cached(nodes + j, &root); + } + + time2 = get_cycles(); + time = time2 - time1; + + time = div_u64(time, perf_loops); + printk(" -> test 2 (latency of nnodes cached insert+delete): %llu cycles\n", (unsigned long long)time); + for (i = 0; i < check_loops; i++) { init(); for (j = 0; j < nnodes; j++) { _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
