1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Data Access Monitor Unit Tests
4 *
5 * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved.
6 *
7 * Author: SeongJae Park <sjpark@amazon.de>
8 */
9
10 #ifdef CONFIG_DAMON_VADDR_KUNIT_TEST
11
12 #ifndef _DAMON_VADDR_TEST_H
13 #define _DAMON_VADDR_TEST_H
14
15 #include <kunit/test.h>
16
__link_vmas(struct maple_tree * mt,struct vm_area_struct * vmas,ssize_t nr_vmas)17 static void __link_vmas(struct maple_tree *mt, struct vm_area_struct *vmas,
18 ssize_t nr_vmas)
19 {
20 int i;
21 MA_STATE(mas, mt, 0, 0);
22
23 if (!nr_vmas)
24 return;
25
26 mas_lock(&mas);
27 for (i = 0; i < nr_vmas; i++)
28 vma_mas_store(&vmas[i], &mas);
29 mas_unlock(&mas);
30 }
31
32 /*
33 * Test __damon_va_three_regions() function
34 *
35 * In case of virtual memory address spaces monitoring, DAMON converts the
36 * complex and dynamic memory mappings of each target task to three
37 * discontiguous regions which cover every mapped areas. However, the three
38 * regions should not include the two biggest unmapped areas in the original
39 * mapping, because the two biggest areas are normally the areas between 1)
40 * heap and the mmap()-ed regions, and 2) the mmap()-ed regions and stack.
41 * Because these two unmapped areas are very huge but obviously never accessed,
42 * covering the region is just a waste.
43 *
44 * '__damon_va_three_regions() receives an address space of a process. It
45 * first identifies the start of mappings, end of mappings, and the two biggest
46 * unmapped areas. After that, based on the information, it constructs the
47 * three regions and returns. For more detail, refer to the comment of
48 * 'damon_init_regions_of()' function definition in 'mm/damon.c' file.
49 *
50 * For example, suppose virtual address ranges of 10-20, 20-25, 200-210,
51 * 210-220, 300-305, and 307-330 (Other comments represent this mappings in
52 * more short form: 10-20-25, 200-210-220, 300-305, 307-330) of a process are
53 * mapped. To cover every mappings, the three regions should start with 10,
54 * and end with 305. The process also has three unmapped areas, 25-200,
55 * 220-300, and 305-307. Among those, 25-200 and 220-300 are the biggest two
56 * unmapped areas, and thus it should be converted to three regions of 10-25,
57 * 200-220, and 300-330.
58 */
damon_test_three_regions_in_vmas(struct kunit * test)59 static void damon_test_three_regions_in_vmas(struct kunit *test)
60 {
61 static struct mm_struct mm;
62 struct damon_addr_range regions[3] = {0,};
63 /* 10-20-25, 200-210-220, 300-305, 307-330 */
64 struct vm_area_struct vmas[] = {
65 (struct vm_area_struct) {.vm_start = 10, .vm_end = 20},
66 (struct vm_area_struct) {.vm_start = 20, .vm_end = 25},
67 (struct vm_area_struct) {.vm_start = 200, .vm_end = 210},
68 (struct vm_area_struct) {.vm_start = 210, .vm_end = 220},
69 (struct vm_area_struct) {.vm_start = 300, .vm_end = 305},
70 (struct vm_area_struct) {.vm_start = 307, .vm_end = 330},
71 };
72
73 mt_init_flags(&mm.mm_mt, MM_MT_FLAGS);
74 __link_vmas(&mm.mm_mt, vmas, ARRAY_SIZE(vmas));
75
76 __damon_va_three_regions(&mm, regions);
77
78 KUNIT_EXPECT_EQ(test, 10ul, regions[0].start);
79 KUNIT_EXPECT_EQ(test, 25ul, regions[0].end);
80 KUNIT_EXPECT_EQ(test, 200ul, regions[1].start);
81 KUNIT_EXPECT_EQ(test, 220ul, regions[1].end);
82 KUNIT_EXPECT_EQ(test, 300ul, regions[2].start);
83 KUNIT_EXPECT_EQ(test, 330ul, regions[2].end);
84 }
85
__nth_region_of(struct damon_target * t,int idx)86 static struct damon_region *__nth_region_of(struct damon_target *t, int idx)
87 {
88 struct damon_region *r;
89 unsigned int i = 0;
90
91 damon_for_each_region(r, t) {
92 if (i++ == idx)
93 return r;
94 }
95
96 return NULL;
97 }
98
99 /*
100 * Test 'damon_set_regions()'
101 *
102 * test kunit object
103 * regions an array containing start/end addresses of current
104 * monitoring target regions
105 * nr_regions the number of the addresses in 'regions'
106 * three_regions The three regions that need to be applied now
107 * expected start/end addresses of monitoring target regions that
108 * 'three_regions' are applied
109 * nr_expected the number of addresses in 'expected'
110 *
111 * The memory mapping of the target processes changes dynamically. To follow
112 * the change, DAMON periodically reads the mappings, simplifies it to the
113 * three regions, and updates the monitoring target regions to fit in the three
114 * regions. The update of current target regions is the role of
115 * 'damon_set_regions()'.
116 *
117 * This test passes the given target regions and the new three regions that
118 * need to be applied to the function and check whether it updates the regions
119 * as expected.
120 */
damon_do_test_apply_three_regions(struct kunit * test,unsigned long * regions,int nr_regions,struct damon_addr_range * three_regions,unsigned long * expected,int nr_expected)121 static void damon_do_test_apply_three_regions(struct kunit *test,
122 unsigned long *regions, int nr_regions,
123 struct damon_addr_range *three_regions,
124 unsigned long *expected, int nr_expected)
125 {
126 struct damon_target *t;
127 struct damon_region *r;
128 int i;
129
130 t = damon_new_target();
131 for (i = 0; i < nr_regions / 2; i++) {
132 r = damon_new_region(regions[i * 2], regions[i * 2 + 1]);
133 damon_add_region(r, t);
134 }
135
136 damon_set_regions(t, three_regions, 3);
137
138 for (i = 0; i < nr_expected / 2; i++) {
139 r = __nth_region_of(t, i);
140 KUNIT_EXPECT_EQ(test, r->ar.start, expected[i * 2]);
141 KUNIT_EXPECT_EQ(test, r->ar.end, expected[i * 2 + 1]);
142 }
143 }
144
145 /*
146 * This function test most common case where the three big regions are only
147 * slightly changed. Target regions should adjust their boundary (10-20-30,
148 * 50-55, 70-80, 90-100) to fit with the new big regions or remove target
149 * regions (57-79) that now out of the three regions.
150 */
damon_test_apply_three_regions1(struct kunit * test)151 static void damon_test_apply_three_regions1(struct kunit *test)
152 {
153 /* 10-20-30, 50-55-57-59, 70-80-90-100 */
154 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,
155 70, 80, 80, 90, 90, 100};
156 /* 5-27, 45-55, 73-104 */
157 struct damon_addr_range new_three_regions[3] = {
158 (struct damon_addr_range){.start = 5, .end = 27},
159 (struct damon_addr_range){.start = 45, .end = 55},
160 (struct damon_addr_range){.start = 73, .end = 104} };
161 /* 5-20-27, 45-55, 73-80-90-104 */
162 unsigned long expected[] = {5, 20, 20, 27, 45, 55,
163 73, 80, 80, 90, 90, 104};
164
165 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),
166 new_three_regions, expected, ARRAY_SIZE(expected));
167 }
168
169 /*
170 * Test slightly bigger change. Similar to above, but the second big region
171 * now require two target regions (50-55, 57-59) to be removed.
172 */
damon_test_apply_three_regions2(struct kunit * test)173 static void damon_test_apply_three_regions2(struct kunit *test)
174 {
175 /* 10-20-30, 50-55-57-59, 70-80-90-100 */
176 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,
177 70, 80, 80, 90, 90, 100};
178 /* 5-27, 56-57, 65-104 */
179 struct damon_addr_range new_three_regions[3] = {
180 (struct damon_addr_range){.start = 5, .end = 27},
181 (struct damon_addr_range){.start = 56, .end = 57},
182 (struct damon_addr_range){.start = 65, .end = 104} };
183 /* 5-20-27, 56-57, 65-80-90-104 */
184 unsigned long expected[] = {5, 20, 20, 27, 56, 57,
185 65, 80, 80, 90, 90, 104};
186
187 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),
188 new_three_regions, expected, ARRAY_SIZE(expected));
189 }
190
191 /*
192 * Test a big change. The second big region has totally freed and mapped to
193 * different area (50-59 -> 61-63). The target regions which were in the old
194 * second big region (50-55-57-59) should be removed and new target region
195 * covering the second big region (61-63) should be created.
196 */
damon_test_apply_three_regions3(struct kunit * test)197 static void damon_test_apply_three_regions3(struct kunit *test)
198 {
199 /* 10-20-30, 50-55-57-59, 70-80-90-100 */
200 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,
201 70, 80, 80, 90, 90, 100};
202 /* 5-27, 61-63, 65-104 */
203 struct damon_addr_range new_three_regions[3] = {
204 (struct damon_addr_range){.start = 5, .end = 27},
205 (struct damon_addr_range){.start = 61, .end = 63},
206 (struct damon_addr_range){.start = 65, .end = 104} };
207 /* 5-20-27, 61-63, 65-80-90-104 */
208 unsigned long expected[] = {5, 20, 20, 27, 61, 63,
209 65, 80, 80, 90, 90, 104};
210
211 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),
212 new_three_regions, expected, ARRAY_SIZE(expected));
213 }
214
215 /*
216 * Test another big change. Both of the second and third big regions (50-59
217 * and 70-100) has totally freed and mapped to different area (30-32 and
218 * 65-68). The target regions which were in the old second and third big
219 * regions should now be removed and new target regions covering the new second
220 * and third big regions should be created.
221 */
damon_test_apply_three_regions4(struct kunit * test)222 static void damon_test_apply_three_regions4(struct kunit *test)
223 {
224 /* 10-20-30, 50-55-57-59, 70-80-90-100 */
225 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,
226 70, 80, 80, 90, 90, 100};
227 /* 5-7, 30-32, 65-68 */
228 struct damon_addr_range new_three_regions[3] = {
229 (struct damon_addr_range){.start = 5, .end = 7},
230 (struct damon_addr_range){.start = 30, .end = 32},
231 (struct damon_addr_range){.start = 65, .end = 68} };
232 /* expect 5-7, 30-32, 65-68 */
233 unsigned long expected[] = {5, 7, 30, 32, 65, 68};
234
235 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),
236 new_three_regions, expected, ARRAY_SIZE(expected));
237 }
238
damon_test_split_evenly_fail(struct kunit * test,unsigned long start,unsigned long end,unsigned int nr_pieces)239 static void damon_test_split_evenly_fail(struct kunit *test,
240 unsigned long start, unsigned long end, unsigned int nr_pieces)
241 {
242 struct damon_target *t = damon_new_target();
243 struct damon_region *r = damon_new_region(start, end);
244
245 damon_add_region(r, t);
246 KUNIT_EXPECT_EQ(test,
247 damon_va_evenly_split_region(t, r, nr_pieces), -EINVAL);
248 KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u);
249
250 damon_for_each_region(r, t) {
251 KUNIT_EXPECT_EQ(test, r->ar.start, start);
252 KUNIT_EXPECT_EQ(test, r->ar.end, end);
253 }
254
255 damon_free_target(t);
256 }
257
damon_test_split_evenly_succ(struct kunit * test,unsigned long start,unsigned long end,unsigned int nr_pieces)258 static void damon_test_split_evenly_succ(struct kunit *test,
259 unsigned long start, unsigned long end, unsigned int nr_pieces)
260 {
261 struct damon_target *t = damon_new_target();
262 struct damon_region *r = damon_new_region(start, end);
263 unsigned long expected_width = (end - start) / nr_pieces;
264 unsigned long i = 0;
265
266 damon_add_region(r, t);
267 KUNIT_EXPECT_EQ(test,
268 damon_va_evenly_split_region(t, r, nr_pieces), 0);
269 KUNIT_EXPECT_EQ(test, damon_nr_regions(t), nr_pieces);
270
271 damon_for_each_region(r, t) {
272 if (i == nr_pieces - 1) {
273 KUNIT_EXPECT_EQ(test,
274 r->ar.start, start + i * expected_width);
275 KUNIT_EXPECT_EQ(test, r->ar.end, end);
276 break;
277 }
278 KUNIT_EXPECT_EQ(test,
279 r->ar.start, start + i++ * expected_width);
280 KUNIT_EXPECT_EQ(test, r->ar.end, start + i * expected_width);
281 }
282 damon_free_target(t);
283 }
284
damon_test_split_evenly(struct kunit * test)285 static void damon_test_split_evenly(struct kunit *test)
286 {
287 KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5),
288 -EINVAL);
289
290 damon_test_split_evenly_fail(test, 0, 100, 0);
291 damon_test_split_evenly_succ(test, 0, 100, 10);
292 damon_test_split_evenly_succ(test, 5, 59, 5);
293 damon_test_split_evenly_fail(test, 5, 6, 2);
294 }
295
296 static struct kunit_case damon_test_cases[] = {
297 KUNIT_CASE(damon_test_three_regions_in_vmas),
298 KUNIT_CASE(damon_test_apply_three_regions1),
299 KUNIT_CASE(damon_test_apply_three_regions2),
300 KUNIT_CASE(damon_test_apply_three_regions3),
301 KUNIT_CASE(damon_test_apply_three_regions4),
302 KUNIT_CASE(damon_test_split_evenly),
303 {},
304 };
305
306 static struct kunit_suite damon_test_suite = {
307 .name = "damon-operations",
308 .test_cases = damon_test_cases,
309 };
310 kunit_test_suite(damon_test_suite);
311
312 #endif /* _DAMON_VADDR_TEST_H */
313
314 #endif /* CONFIG_DAMON_VADDR_KUNIT_TEST */
315
