1 | #include <linux/device.h> |
2 | #include <linux/dma-map-ops.h> |
3 | #include <linux/dma-mapping.h> |
4 | #include <linux/dmapool.h> |
5 | #include <linux/kernel.h> |
6 | #include <linux/ktime.h> |
7 | #include <linux/module.h> |
8 | |
9 | #define NR_TESTS (100) |
10 | |
11 | struct dma_pool_pair { |
12 | dma_addr_t dma; |
13 | void *v; |
14 | }; |
15 | |
16 | struct dmapool_parms { |
17 | size_t size; |
18 | size_t align; |
19 | size_t boundary; |
20 | }; |
21 | |
22 | static const struct dmapool_parms pool_parms[] = { |
23 | { .size = 16, .align = 16, .boundary = 0 }, |
24 | { .size = 64, .align = 64, .boundary = 0 }, |
25 | { .size = 256, .align = 256, .boundary = 0 }, |
26 | { .size = 1024, .align = 1024, .boundary = 0 }, |
27 | { .size = 4096, .align = 4096, .boundary = 0 }, |
28 | { .size = 68, .align = 32, .boundary = 4096 }, |
29 | }; |
30 | |
31 | static struct dma_pool *pool; |
32 | static struct device test_dev; |
33 | static u64 dma_mask; |
34 | |
35 | static inline int nr_blocks(int size) |
36 | { |
37 | return clamp_t(int, (PAGE_SIZE / size) * 512, 1024, 8192); |
38 | } |
39 | |
40 | static int dmapool_test_alloc(struct dma_pool_pair *p, int blocks) |
41 | { |
42 | int i; |
43 | |
44 | for (i = 0; i < blocks; i++) { |
45 | p[i].v = dma_pool_alloc(pool, GFP_KERNEL, |
46 | handle: &p[i].dma); |
47 | if (!p[i].v) |
48 | goto pool_fail; |
49 | } |
50 | |
51 | for (i = 0; i < blocks; i++) |
52 | dma_pool_free(pool, vaddr: p[i].v, addr: p[i].dma); |
53 | |
54 | return 0; |
55 | |
56 | pool_fail: |
57 | for (--i; i >= 0; i--) |
58 | dma_pool_free(pool, vaddr: p[i].v, addr: p[i].dma); |
59 | return -ENOMEM; |
60 | } |
61 | |
62 | static int dmapool_test_block(const struct dmapool_parms *parms) |
63 | { |
64 | int blocks = nr_blocks(size: parms->size); |
65 | ktime_t start_time, end_time; |
66 | struct dma_pool_pair *p; |
67 | int i, ret; |
68 | |
69 | p = kcalloc(n: blocks, size: sizeof(*p), GFP_KERNEL); |
70 | if (!p) |
71 | return -ENOMEM; |
72 | |
73 | pool = dma_pool_create(name: "test pool" , dev: &test_dev, size: parms->size, |
74 | align: parms->align, allocation: parms->boundary); |
75 | if (!pool) { |
76 | ret = -ENOMEM; |
77 | goto free_pairs; |
78 | } |
79 | |
80 | start_time = ktime_get(); |
81 | for (i = 0; i < NR_TESTS; i++) { |
82 | ret = dmapool_test_alloc(p, blocks); |
83 | if (ret) |
84 | goto free_pool; |
85 | if (need_resched()) |
86 | cond_resched(); |
87 | } |
88 | end_time = ktime_get(); |
89 | |
90 | printk("dmapool test: size:%-4zu align:%-4zu blocks:%-4d time:%llu\n" , |
91 | parms->size, parms->align, blocks, |
92 | ktime_us_delta(end_time, start_time)); |
93 | |
94 | free_pool: |
95 | dma_pool_destroy(pool); |
96 | free_pairs: |
97 | kfree(objp: p); |
98 | return ret; |
99 | } |
100 | |
101 | static void dmapool_test_release(struct device *dev) |
102 | { |
103 | } |
104 | |
105 | static int dmapool_checks(void) |
106 | { |
107 | int i, ret; |
108 | |
109 | ret = dev_set_name(dev: &test_dev, name: "dmapool-test" ); |
110 | if (ret) |
111 | return ret; |
112 | |
113 | ret = device_register(dev: &test_dev); |
114 | if (ret) { |
115 | printk("%s: register failed:%d\n" , __func__, ret); |
116 | goto put_device; |
117 | } |
118 | |
119 | test_dev.release = dmapool_test_release; |
120 | set_dma_ops(dev: &test_dev, NULL); |
121 | test_dev.dma_mask = &dma_mask; |
122 | ret = dma_set_mask_and_coherent(dev: &test_dev, DMA_BIT_MASK(64)); |
123 | if (ret) { |
124 | printk("%s: mask failed:%d\n" , __func__, ret); |
125 | goto del_device; |
126 | } |
127 | |
128 | for (i = 0; i < ARRAY_SIZE(pool_parms); i++) { |
129 | ret = dmapool_test_block(parms: &pool_parms[i]); |
130 | if (ret) |
131 | break; |
132 | } |
133 | |
134 | del_device: |
135 | device_del(dev: &test_dev); |
136 | put_device: |
137 | put_device(dev: &test_dev); |
138 | return ret; |
139 | } |
140 | |
141 | static void dmapool_exit(void) |
142 | { |
143 | } |
144 | |
145 | module_init(dmapool_checks); |
146 | module_exit(dmapool_exit); |
147 | MODULE_LICENSE("GPL" ); |
148 | |