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