1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * benchmark.c:
4  * Author: Konstantin Khlebnikov <koct9i@gmail.com>
5  */
6 #include <linux/radix-tree.h>
7 #include <linux/slab.h>
8 #include <linux/errno.h>
9 #include <time.h>
10 #include "test.h"
11 
12 #define NSEC_PER_SEC	1000000000L
13 
14 static long long benchmark_iter(struct radix_tree_root *root, bool tagged)
15 {
16 	volatile unsigned long sink = 0;
17 	struct radix_tree_iter iter;
18 	struct timespec start, finish;
19 	long long nsec;
20 	int l, loops = 1;
21 	void **slot;
22 
23 #ifdef BENCHMARK
24 again:
25 #endif
26 	clock_gettime(CLOCK_MONOTONIC, &start);
27 	for (l = 0; l < loops; l++) {
28 		if (tagged) {
29 			radix_tree_for_each_tagged(slot, root, &iter, 0, 0)
30 				sink ^= (unsigned long)slot;
31 		} else {
32 			radix_tree_for_each_slot(slot, root, &iter, 0)
33 				sink ^= (unsigned long)slot;
34 		}
35 	}
36 	clock_gettime(CLOCK_MONOTONIC, &finish);
37 
38 	nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC +
39 	       (finish.tv_nsec - start.tv_nsec);
40 
41 #ifdef BENCHMARK
42 	if (loops == 1 && nsec * 5 < NSEC_PER_SEC) {
43 		loops = NSEC_PER_SEC / nsec / 4 + 1;
44 		goto again;
45 	}
46 #endif
47 
48 	nsec /= loops;
49 	return nsec;
50 }
51 
52 static void benchmark_insert(struct radix_tree_root *root,
53 			     unsigned long size, unsigned long step)
54 {
55 	struct timespec start, finish;
56 	unsigned long index;
57 	long long nsec;
58 
59 	clock_gettime(CLOCK_MONOTONIC, &start);
60 
61 	for (index = 0 ; index < size ; index += step)
62 		item_insert(root, index);
63 
64 	clock_gettime(CLOCK_MONOTONIC, &finish);
65 
66 	nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC +
67 	       (finish.tv_nsec - start.tv_nsec);
68 
69 	printv(2, "Size: %8ld, step: %8ld, insertion: %15lld ns\n",
70 		size, step, nsec);
71 }
72 
73 static void benchmark_tagging(struct radix_tree_root *root,
74 			     unsigned long size, unsigned long step)
75 {
76 	struct timespec start, finish;
77 	unsigned long index;
78 	long long nsec;
79 
80 	clock_gettime(CLOCK_MONOTONIC, &start);
81 
82 	for (index = 0 ; index < size ; index += step)
83 		radix_tree_tag_set(root, index, 0);
84 
85 	clock_gettime(CLOCK_MONOTONIC, &finish);
86 
87 	nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC +
88 	       (finish.tv_nsec - start.tv_nsec);
89 
90 	printv(2, "Size: %8ld, step: %8ld, tagging: %17lld ns\n",
91 		size, step, nsec);
92 }
93 
94 static void benchmark_delete(struct radix_tree_root *root,
95 			     unsigned long size, unsigned long step)
96 {
97 	struct timespec start, finish;
98 	unsigned long index;
99 	long long nsec;
100 
101 	clock_gettime(CLOCK_MONOTONIC, &start);
102 
103 	for (index = 0 ; index < size ; index += step)
104 		item_delete(root, index);
105 
106 	clock_gettime(CLOCK_MONOTONIC, &finish);
107 
108 	nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC +
109 	       (finish.tv_nsec - start.tv_nsec);
110 
111 	printv(2, "Size: %8ld, step: %8ld, deletion: %16lld ns\n",
112 		size, step, nsec);
113 }
114 
115 static void benchmark_size(unsigned long size, unsigned long step)
116 {
117 	RADIX_TREE(tree, GFP_KERNEL);
118 	long long normal, tagged;
119 
120 	benchmark_insert(&tree, size, step);
121 	benchmark_tagging(&tree, size, step);
122 
123 	tagged = benchmark_iter(&tree, true);
124 	normal = benchmark_iter(&tree, false);
125 
126 	printv(2, "Size: %8ld, step: %8ld, tagged iteration: %8lld ns\n",
127 		size, step, tagged);
128 	printv(2, "Size: %8ld, step: %8ld, normal iteration: %8lld ns\n",
129 		size, step, normal);
130 
131 	benchmark_delete(&tree, size, step);
132 
133 	item_kill_tree(&tree);
134 	rcu_barrier();
135 }
136 
137 void benchmark(void)
138 {
139 	unsigned long size[] = {1 << 10, 1 << 20, 0};
140 	unsigned long step[] = {1, 2, 7, 15, 63, 64, 65,
141 				128, 256, 512, 12345, 0};
142 	int c, s;
143 
144 	printv(1, "starting benchmarks\n");
145 	printv(1, "RADIX_TREE_MAP_SHIFT = %d\n", RADIX_TREE_MAP_SHIFT);
146 
147 	for (c = 0; size[c]; c++)
148 		for (s = 0; step[s]; s++)
149 			benchmark_size(size[c], step[s]);
150 }
151