xref: /linux/tools/testing/selftests/dma/dma_map_benchmark.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2020 HiSilicon Limited.
4  */
5 
6 #include <fcntl.h>
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <unistd.h>
11 #include <sys/ioctl.h>
12 #include <sys/mman.h>
13 #include <linux/types.h>
14 #include <linux/map_benchmark.h>
15 
16 #define NSEC_PER_MSEC	1000000L
17 
18 static char *directions[] = {
19 	"BIDIRECTIONAL",
20 	"TO_DEVICE",
21 	"FROM_DEVICE",
22 };
23 
24 int main(int argc, char **argv)
25 {
26 	struct map_benchmark map;
27 	int fd, opt;
28 	/* default single thread, run 20 seconds on NUMA_NO_NODE */
29 	int threads = 1, seconds = 20, node = -1;
30 	/* default dma mask 32bit, bidirectional DMA */
31 	int bits = 32, xdelay = 0, dir = DMA_MAP_BIDIRECTIONAL;
32 	/* default granule 1 PAGESIZE */
33 	int granule = 1;
34 
35 	int cmd = DMA_MAP_BENCHMARK;
36 
37 	while ((opt = getopt(argc, argv, "t:s:n:b:d:x:g:")) != -1) {
38 		switch (opt) {
39 		case 't':
40 			threads = atoi(optarg);
41 			break;
42 		case 's':
43 			seconds = atoi(optarg);
44 			break;
45 		case 'n':
46 			node = atoi(optarg);
47 			break;
48 		case 'b':
49 			bits = atoi(optarg);
50 			break;
51 		case 'd':
52 			dir = atoi(optarg);
53 			break;
54 		case 'x':
55 			xdelay = atoi(optarg);
56 			break;
57 		case 'g':
58 			granule = atoi(optarg);
59 			break;
60 		default:
61 			return -1;
62 		}
63 	}
64 
65 	if (threads <= 0 || threads > DMA_MAP_MAX_THREADS) {
66 		fprintf(stderr, "invalid number of threads, must be in 1-%d\n",
67 			DMA_MAP_MAX_THREADS);
68 		exit(1);
69 	}
70 
71 	if (seconds <= 0 || seconds > DMA_MAP_MAX_SECONDS) {
72 		fprintf(stderr, "invalid number of seconds, must be in 1-%d\n",
73 			DMA_MAP_MAX_SECONDS);
74 		exit(1);
75 	}
76 
77 	if (xdelay < 0 || xdelay > DMA_MAP_MAX_TRANS_DELAY) {
78 		fprintf(stderr, "invalid transmit delay, must be in 0-%ld\n",
79 			DMA_MAP_MAX_TRANS_DELAY);
80 		exit(1);
81 	}
82 
83 	/* suppose the mininum DMA zone is 1MB in the world */
84 	if (bits < 20 || bits > 64) {
85 		fprintf(stderr, "invalid dma mask bit, must be in 20-64\n");
86 		exit(1);
87 	}
88 
89 	if (dir != DMA_MAP_BIDIRECTIONAL && dir != DMA_MAP_TO_DEVICE &&
90 			dir != DMA_MAP_FROM_DEVICE) {
91 		fprintf(stderr, "invalid dma direction\n");
92 		exit(1);
93 	}
94 
95 	if (granule < 1 || granule > 1024) {
96 		fprintf(stderr, "invalid granule size\n");
97 		exit(1);
98 	}
99 
100 	fd = open("/sys/kernel/debug/dma_map_benchmark", O_RDWR);
101 	if (fd == -1) {
102 		perror("open");
103 		exit(1);
104 	}
105 
106 	memset(&map, 0, sizeof(map));
107 	map.seconds = seconds;
108 	map.threads = threads;
109 	map.node = node;
110 	map.dma_bits = bits;
111 	map.dma_dir = dir;
112 	map.dma_trans_ns = xdelay;
113 	map.granule = granule;
114 
115 	if (ioctl(fd, cmd, &map)) {
116 		perror("ioctl");
117 		exit(1);
118 	}
119 
120 	printf("dma mapping benchmark: threads:%d seconds:%d node:%d dir:%s granule: %d\n",
121 			threads, seconds, node, dir[directions], granule);
122 	printf("average map latency(us):%.1f standard deviation:%.1f\n",
123 			map.avg_map_100ns/10.0, map.map_stddev/10.0);
124 	printf("average unmap latency(us):%.1f standard deviation:%.1f\n",
125 			map.avg_unmap_100ns/10.0, map.unmap_stddev/10.0);
126 
127 	return 0;
128 }
129