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 <sj@kernel.org> 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 17 static int __link_vmas(struct maple_tree *mt, struct vm_area_struct *vmas, 18 ssize_t nr_vmas) 19 { 20 int i, ret = -ENOMEM; 21 MA_STATE(mas, mt, 0, 0); 22 23 if (!nr_vmas) 24 return 0; 25 26 mas_lock(&mas); 27 for (i = 0; i < nr_vmas; i++) { 28 mas_set_range(&mas, vmas[i].vm_start, vmas[i].vm_end - 1); 29 if (mas_store_gfp(&mas, &vmas[i], GFP_KERNEL)) 30 goto failed; 31 } 32 33 ret = 0; 34 failed: 35 mas_unlock(&mas); 36 return ret; 37 } 38 39 /* 40 * Test __damon_va_three_regions() function 41 * 42 * In case of virtual memory address spaces monitoring, DAMON converts the 43 * complex and dynamic memory mappings of each target task to three 44 * discontiguous regions which cover every mapped areas. However, the three 45 * regions should not include the two biggest unmapped areas in the original 46 * mapping, because the two biggest areas are normally the areas between 1) 47 * heap and the mmap()-ed regions, and 2) the mmap()-ed regions and stack. 48 * Because these two unmapped areas are very huge but obviously never accessed, 49 * covering the region is just a waste. 50 * 51 * '__damon_va_three_regions() receives an address space of a process. It 52 * first identifies the start of mappings, end of mappings, and the two biggest 53 * unmapped areas. After that, based on the information, it constructs the 54 * three regions and returns. For more detail, refer to the comment of 55 * 'damon_init_regions_of()' function definition in 'mm/damon.c' file. 56 * 57 * For example, suppose virtual address ranges of 10-20, 20-25, 200-210, 58 * 210-220, 300-305, and 307-330 (Other comments represent this mappings in 59 * more short form: 10-20-25, 200-210-220, 300-305, 307-330) of a process are 60 * mapped. To cover every mappings, the three regions should start with 10, 61 * and end with 305. The process also has three unmapped areas, 25-200, 62 * 220-300, and 305-307. Among those, 25-200 and 220-300 are the biggest two 63 * unmapped areas, and thus it should be converted to three regions of 10-25, 64 * 200-220, and 300-330. 65 */ 66 static void damon_test_three_regions_in_vmas(struct kunit *test) 67 { 68 static struct mm_struct mm; 69 struct damon_addr_range regions[3] = {0}; 70 /* 10-20-25, 200-210-220, 300-305, 307-330 */ 71 static struct vm_area_struct vmas[] = { 72 (struct vm_area_struct) {.vm_start = 10, .vm_end = 20}, 73 (struct vm_area_struct) {.vm_start = 20, .vm_end = 25}, 74 (struct vm_area_struct) {.vm_start = 200, .vm_end = 210}, 75 (struct vm_area_struct) {.vm_start = 210, .vm_end = 220}, 76 (struct vm_area_struct) {.vm_start = 300, .vm_end = 305}, 77 (struct vm_area_struct) {.vm_start = 307, .vm_end = 330}, 78 }; 79 80 mt_init_flags(&mm.mm_mt, MT_FLAGS_ALLOC_RANGE | MT_FLAGS_USE_RCU); 81 if (__link_vmas(&mm.mm_mt, vmas, ARRAY_SIZE(vmas))) 82 kunit_skip(test, "Failed to create VMA tree"); 83 84 __damon_va_three_regions(&mm, regions); 85 86 KUNIT_EXPECT_EQ(test, 10ul, regions[0].start); 87 KUNIT_EXPECT_EQ(test, 25ul, regions[0].end); 88 KUNIT_EXPECT_EQ(test, 200ul, regions[1].start); 89 KUNIT_EXPECT_EQ(test, 220ul, regions[1].end); 90 KUNIT_EXPECT_EQ(test, 300ul, regions[2].start); 91 KUNIT_EXPECT_EQ(test, 330ul, regions[2].end); 92 } 93 94 static struct damon_region *__nth_region_of(struct damon_target *t, int idx) 95 { 96 struct damon_region *r; 97 unsigned int i = 0; 98 99 damon_for_each_region(r, t) { 100 if (i++ == idx) 101 return r; 102 } 103 104 return NULL; 105 } 106 107 /* 108 * Test 'damon_set_regions()' 109 * 110 * test kunit object 111 * regions an array containing start/end addresses of current 112 * monitoring target regions 113 * nr_regions the number of the addresses in 'regions' 114 * three_regions The three regions that need to be applied now 115 * expected start/end addresses of monitoring target regions that 116 * 'three_regions' are applied 117 * nr_expected the number of addresses in 'expected' 118 * 119 * The memory mapping of the target processes changes dynamically. To follow 120 * the change, DAMON periodically reads the mappings, simplifies it to the 121 * three regions, and updates the monitoring target regions to fit in the three 122 * regions. The update of current target regions is the role of 123 * 'damon_set_regions()'. 124 * 125 * This test passes the given target regions and the new three regions that 126 * need to be applied to the function and check whether it updates the regions 127 * as expected. 128 */ 129 static void damon_do_test_apply_three_regions(struct kunit *test, 130 unsigned long *regions, int nr_regions, 131 struct damon_addr_range *three_regions, 132 unsigned long *expected, int nr_expected) 133 { 134 struct damon_target *t; 135 struct damon_region *r; 136 int i; 137 138 t = damon_new_target(); 139 if (!t) 140 kunit_skip(test, "target alloc fail"); 141 for (i = 0; i < nr_regions / 2; i++) { 142 r = damon_new_region(regions[i * 2], regions[i * 2 + 1]); 143 if (!r) { 144 damon_destroy_target(t, NULL); 145 kunit_skip(test, "region alloc fail"); 146 } 147 damon_add_region(r, t); 148 } 149 150 damon_set_regions(t, three_regions, 3, DAMON_MIN_REGION); 151 152 for (i = 0; i < nr_expected / 2; i++) { 153 r = __nth_region_of(t, i); 154 KUNIT_EXPECT_EQ(test, r->ar.start, expected[i * 2]); 155 KUNIT_EXPECT_EQ(test, r->ar.end, expected[i * 2 + 1]); 156 } 157 158 damon_destroy_target(t, NULL); 159 } 160 161 /* 162 * This function test most common case where the three big regions are only 163 * slightly changed. Target regions should adjust their boundary (10-20-30, 164 * 50-55, 70-80, 90-100) to fit with the new big regions or remove target 165 * regions (57-79) that now out of the three regions. 166 */ 167 static void damon_test_apply_three_regions1(struct kunit *test) 168 { 169 /* 10-20-30, 50-55-57-59, 70-80-90-100 */ 170 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, 171 70, 80, 80, 90, 90, 100}; 172 /* 5-27, 45-55, 73-104 */ 173 struct damon_addr_range new_three_regions[3] = { 174 (struct damon_addr_range){.start = 5, .end = 27}, 175 (struct damon_addr_range){.start = 45, .end = 55}, 176 (struct damon_addr_range){.start = 73, .end = 104} }; 177 /* 5-20-27, 45-55, 73-80-90-104 */ 178 unsigned long expected[] = {5, 20, 20, 27, 45, 55, 179 73, 80, 80, 90, 90, 104}; 180 181 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), 182 new_three_regions, expected, ARRAY_SIZE(expected)); 183 } 184 185 /* 186 * Test slightly bigger change. Similar to above, but the second big region 187 * now require two target regions (50-55, 57-59) to be removed. 188 */ 189 static void damon_test_apply_three_regions2(struct kunit *test) 190 { 191 /* 10-20-30, 50-55-57-59, 70-80-90-100 */ 192 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, 193 70, 80, 80, 90, 90, 100}; 194 /* 5-27, 56-57, 65-104 */ 195 struct damon_addr_range new_three_regions[3] = { 196 (struct damon_addr_range){.start = 5, .end = 27}, 197 (struct damon_addr_range){.start = 56, .end = 57}, 198 (struct damon_addr_range){.start = 65, .end = 104} }; 199 /* 5-20-27, 56-57, 65-80-90-104 */ 200 unsigned long expected[] = {5, 20, 20, 27, 56, 57, 201 65, 80, 80, 90, 90, 104}; 202 203 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), 204 new_three_regions, expected, ARRAY_SIZE(expected)); 205 } 206 207 /* 208 * Test a big change. The second big region has totally freed and mapped to 209 * different area (50-59 -> 61-63). The target regions which were in the old 210 * second big region (50-55-57-59) should be removed and new target region 211 * covering the second big region (61-63) should be created. 212 */ 213 static void damon_test_apply_three_regions3(struct kunit *test) 214 { 215 /* 10-20-30, 50-55-57-59, 70-80-90-100 */ 216 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, 217 70, 80, 80, 90, 90, 100}; 218 /* 5-27, 61-63, 65-104 */ 219 struct damon_addr_range new_three_regions[3] = { 220 (struct damon_addr_range){.start = 5, .end = 27}, 221 (struct damon_addr_range){.start = 61, .end = 63}, 222 (struct damon_addr_range){.start = 65, .end = 104} }; 223 /* 5-20-27, 61-63, 65-80-90-104 */ 224 unsigned long expected[] = {5, 20, 20, 27, 61, 63, 225 65, 80, 80, 90, 90, 104}; 226 227 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), 228 new_three_regions, expected, ARRAY_SIZE(expected)); 229 } 230 231 /* 232 * Test another big change. Both of the second and third big regions (50-59 233 * and 70-100) has totally freed and mapped to different area (30-32 and 234 * 65-68). The target regions which were in the old second and third big 235 * regions should now be removed and new target regions covering the new second 236 * and third big regions should be created. 237 */ 238 static void damon_test_apply_three_regions4(struct kunit *test) 239 { 240 /* 10-20-30, 50-55-57-59, 70-80-90-100 */ 241 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59, 242 70, 80, 80, 90, 90, 100}; 243 /* 5-7, 30-32, 65-68 */ 244 struct damon_addr_range new_three_regions[3] = { 245 (struct damon_addr_range){.start = 5, .end = 7}, 246 (struct damon_addr_range){.start = 30, .end = 32}, 247 (struct damon_addr_range){.start = 65, .end = 68} }; 248 /* expect 5-7, 30-32, 65-68 */ 249 unsigned long expected[] = {5, 7, 30, 32, 65, 68}; 250 251 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions), 252 new_three_regions, expected, ARRAY_SIZE(expected)); 253 } 254 255 static void damon_test_split_evenly_fail(struct kunit *test, 256 unsigned long start, unsigned long end, unsigned int nr_pieces) 257 { 258 struct damon_target *t = damon_new_target(); 259 struct damon_region *r; 260 261 if (!t) 262 kunit_skip(test, "target alloc fail"); 263 264 r = damon_new_region(start, end); 265 if (!r) { 266 damon_free_target(t); 267 kunit_skip(test, "region alloc fail"); 268 } 269 270 damon_add_region(r, t); 271 KUNIT_EXPECT_EQ(test, 272 damon_va_evenly_split_region(t, r, nr_pieces), -EINVAL); 273 KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u); 274 275 damon_for_each_region(r, t) { 276 KUNIT_EXPECT_EQ(test, r->ar.start, start); 277 KUNIT_EXPECT_EQ(test, r->ar.end, end); 278 } 279 280 damon_free_target(t); 281 } 282 283 static void damon_test_split_evenly_succ(struct kunit *test, 284 unsigned long start, unsigned long end, unsigned int nr_pieces) 285 { 286 struct damon_target *t = damon_new_target(); 287 struct damon_region *r; 288 unsigned long expected_width = (end - start) / nr_pieces; 289 unsigned long i = 0; 290 291 if (!t) 292 kunit_skip(test, "target alloc fail"); 293 r = damon_new_region(start, end); 294 if (!r) { 295 damon_free_target(t); 296 kunit_skip(test, "region alloc fail"); 297 } 298 damon_add_region(r, t); 299 KUNIT_EXPECT_EQ(test, 300 damon_va_evenly_split_region(t, r, nr_pieces), 0); 301 KUNIT_EXPECT_EQ(test, damon_nr_regions(t), nr_pieces); 302 303 damon_for_each_region(r, t) { 304 if (i == nr_pieces - 1) { 305 KUNIT_EXPECT_EQ(test, 306 r->ar.start, start + i * expected_width); 307 KUNIT_EXPECT_EQ(test, r->ar.end, end); 308 break; 309 } 310 KUNIT_EXPECT_EQ(test, 311 r->ar.start, start + i++ * expected_width); 312 KUNIT_EXPECT_EQ(test, r->ar.end, start + i * expected_width); 313 } 314 damon_free_target(t); 315 } 316 317 static void damon_test_split_evenly(struct kunit *test) 318 { 319 KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5), 320 -EINVAL); 321 322 damon_test_split_evenly_fail(test, 0, 100, 0); 323 damon_test_split_evenly_succ(test, 0, 100, 10); 324 damon_test_split_evenly_succ(test, 5, 59, 5); 325 damon_test_split_evenly_succ(test, 4, 6, 1); 326 damon_test_split_evenly_succ(test, 0, 3, 2); 327 damon_test_split_evenly_fail(test, 5, 6, 2); 328 } 329 330 static struct kunit_case damon_test_cases[] = { 331 KUNIT_CASE(damon_test_three_regions_in_vmas), 332 KUNIT_CASE(damon_test_apply_three_regions1), 333 KUNIT_CASE(damon_test_apply_three_regions2), 334 KUNIT_CASE(damon_test_apply_three_regions3), 335 KUNIT_CASE(damon_test_apply_three_regions4), 336 KUNIT_CASE(damon_test_split_evenly), 337 {}, 338 }; 339 340 static struct kunit_suite damon_test_suite = { 341 .name = "damon-operations", 342 .test_cases = damon_test_cases, 343 }; 344 kunit_test_suite(damon_test_suite); 345 346 #endif /* _DAMON_VADDR_TEST_H */ 347 348 #endif /* CONFIG_DAMON_VADDR_KUNIT_TEST */ 349