325 lines · c
1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Data Access Monitor Unit Tests4 *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_TEST11 12#ifndef _DAMON_VADDR_TEST_H13#define _DAMON_VADDR_TEST_H14 15#include <kunit/test.h>16 17static 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;34failed:35 mas_unlock(&mas);36 return ret;37}38 39/*40 * Test __damon_va_three_regions() function41 *42 * In case of virtual memory address spaces monitoring, DAMON converts the43 * complex and dynamic memory mappings of each target task to three44 * discontiguous regions which cover every mapped areas. However, the three45 * regions should not include the two biggest unmapped areas in the original46 * 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. It52 * first identifies the start of mappings, end of mappings, and the two biggest53 * unmapped areas. After that, based on the information, it constructs the54 * three regions and returns. For more detail, refer to the comment of55 * '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 in59 * more short form: 10-20-25, 200-210-220, 300-305, 307-330) of a process are60 * 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 two63 * unmapped areas, and thus it should be converted to three regions of 10-25,64 * 200-220, and 300-330.65 */66static 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 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 94static 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 object111 * regions an array containing start/end addresses of current112 * monitoring target regions113 * nr_regions the number of the addresses in 'regions'114 * three_regions The three regions that need to be applied now115 * expected start/end addresses of monitoring target regions that116 * 'three_regions' are applied117 * nr_expected the number of addresses in 'expected'118 *119 * The memory mapping of the target processes changes dynamically. To follow120 * the change, DAMON periodically reads the mappings, simplifies it to the121 * three regions, and updates the monitoring target regions to fit in the three122 * regions. The update of current target regions is the role of123 * 'damon_set_regions()'.124 *125 * This test passes the given target regions and the new three regions that126 * need to be applied to the function and check whether it updates the regions127 * as expected.128 */129static 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 for (i = 0; i < nr_regions / 2; i++) {140 r = damon_new_region(regions[i * 2], regions[i * 2 + 1]);141 damon_add_region(r, t);142 }143 144 damon_set_regions(t, three_regions, 3);145 146 for (i = 0; i < nr_expected / 2; i++) {147 r = __nth_region_of(t, i);148 KUNIT_EXPECT_EQ(test, r->ar.start, expected[i * 2]);149 KUNIT_EXPECT_EQ(test, r->ar.end, expected[i * 2 + 1]);150 }151 152 damon_destroy_target(t);153}154 155/*156 * This function test most common case where the three big regions are only157 * slightly changed. Target regions should adjust their boundary (10-20-30,158 * 50-55, 70-80, 90-100) to fit with the new big regions or remove target159 * regions (57-79) that now out of the three regions.160 */161static void damon_test_apply_three_regions1(struct kunit *test)162{163 /* 10-20-30, 50-55-57-59, 70-80-90-100 */164 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,165 70, 80, 80, 90, 90, 100};166 /* 5-27, 45-55, 73-104 */167 struct damon_addr_range new_three_regions[3] = {168 (struct damon_addr_range){.start = 5, .end = 27},169 (struct damon_addr_range){.start = 45, .end = 55},170 (struct damon_addr_range){.start = 73, .end = 104} };171 /* 5-20-27, 45-55, 73-80-90-104 */172 unsigned long expected[] = {5, 20, 20, 27, 45, 55,173 73, 80, 80, 90, 90, 104};174 175 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),176 new_three_regions, expected, ARRAY_SIZE(expected));177}178 179/*180 * Test slightly bigger change. Similar to above, but the second big region181 * now require two target regions (50-55, 57-59) to be removed.182 */183static void damon_test_apply_three_regions2(struct kunit *test)184{185 /* 10-20-30, 50-55-57-59, 70-80-90-100 */186 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,187 70, 80, 80, 90, 90, 100};188 /* 5-27, 56-57, 65-104 */189 struct damon_addr_range new_three_regions[3] = {190 (struct damon_addr_range){.start = 5, .end = 27},191 (struct damon_addr_range){.start = 56, .end = 57},192 (struct damon_addr_range){.start = 65, .end = 104} };193 /* 5-20-27, 56-57, 65-80-90-104 */194 unsigned long expected[] = {5, 20, 20, 27, 56, 57,195 65, 80, 80, 90, 90, 104};196 197 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),198 new_three_regions, expected, ARRAY_SIZE(expected));199}200 201/*202 * Test a big change. The second big region has totally freed and mapped to203 * different area (50-59 -> 61-63). The target regions which were in the old204 * second big region (50-55-57-59) should be removed and new target region205 * covering the second big region (61-63) should be created.206 */207static void damon_test_apply_three_regions3(struct kunit *test)208{209 /* 10-20-30, 50-55-57-59, 70-80-90-100 */210 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,211 70, 80, 80, 90, 90, 100};212 /* 5-27, 61-63, 65-104 */213 struct damon_addr_range new_three_regions[3] = {214 (struct damon_addr_range){.start = 5, .end = 27},215 (struct damon_addr_range){.start = 61, .end = 63},216 (struct damon_addr_range){.start = 65, .end = 104} };217 /* 5-20-27, 61-63, 65-80-90-104 */218 unsigned long expected[] = {5, 20, 20, 27, 61, 63,219 65, 80, 80, 90, 90, 104};220 221 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),222 new_three_regions, expected, ARRAY_SIZE(expected));223}224 225/*226 * Test another big change. Both of the second and third big regions (50-59227 * and 70-100) has totally freed and mapped to different area (30-32 and228 * 65-68). The target regions which were in the old second and third big229 * regions should now be removed and new target regions covering the new second230 * and third big regions should be created.231 */232static void damon_test_apply_three_regions4(struct kunit *test)233{234 /* 10-20-30, 50-55-57-59, 70-80-90-100 */235 unsigned long regions[] = {10, 20, 20, 30, 50, 55, 55, 57, 57, 59,236 70, 80, 80, 90, 90, 100};237 /* 5-7, 30-32, 65-68 */238 struct damon_addr_range new_three_regions[3] = {239 (struct damon_addr_range){.start = 5, .end = 7},240 (struct damon_addr_range){.start = 30, .end = 32},241 (struct damon_addr_range){.start = 65, .end = 68} };242 /* expect 5-7, 30-32, 65-68 */243 unsigned long expected[] = {5, 7, 30, 32, 65, 68};244 245 damon_do_test_apply_three_regions(test, regions, ARRAY_SIZE(regions),246 new_three_regions, expected, ARRAY_SIZE(expected));247}248 249static void damon_test_split_evenly_fail(struct kunit *test,250 unsigned long start, unsigned long end, unsigned int nr_pieces)251{252 struct damon_target *t = damon_new_target();253 struct damon_region *r = damon_new_region(start, end);254 255 damon_add_region(r, t);256 KUNIT_EXPECT_EQ(test,257 damon_va_evenly_split_region(t, r, nr_pieces), -EINVAL);258 KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 1u);259 260 damon_for_each_region(r, t) {261 KUNIT_EXPECT_EQ(test, r->ar.start, start);262 KUNIT_EXPECT_EQ(test, r->ar.end, end);263 }264 265 damon_free_target(t);266}267 268static void damon_test_split_evenly_succ(struct kunit *test,269 unsigned long start, unsigned long end, unsigned int nr_pieces)270{271 struct damon_target *t = damon_new_target();272 struct damon_region *r = damon_new_region(start, end);273 unsigned long expected_width = (end - start) / nr_pieces;274 unsigned long i = 0;275 276 damon_add_region(r, t);277 KUNIT_EXPECT_EQ(test,278 damon_va_evenly_split_region(t, r, nr_pieces), 0);279 KUNIT_EXPECT_EQ(test, damon_nr_regions(t), nr_pieces);280 281 damon_for_each_region(r, t) {282 if (i == nr_pieces - 1) {283 KUNIT_EXPECT_EQ(test,284 r->ar.start, start + i * expected_width);285 KUNIT_EXPECT_EQ(test, r->ar.end, end);286 break;287 }288 KUNIT_EXPECT_EQ(test,289 r->ar.start, start + i++ * expected_width);290 KUNIT_EXPECT_EQ(test, r->ar.end, start + i * expected_width);291 }292 damon_free_target(t);293}294 295static void damon_test_split_evenly(struct kunit *test)296{297 KUNIT_EXPECT_EQ(test, damon_va_evenly_split_region(NULL, NULL, 5),298 -EINVAL);299 300 damon_test_split_evenly_fail(test, 0, 100, 0);301 damon_test_split_evenly_succ(test, 0, 100, 10);302 damon_test_split_evenly_succ(test, 5, 59, 5);303 damon_test_split_evenly_fail(test, 5, 6, 2);304}305 306static struct kunit_case damon_test_cases[] = {307 KUNIT_CASE(damon_test_three_regions_in_vmas),308 KUNIT_CASE(damon_test_apply_three_regions1),309 KUNIT_CASE(damon_test_apply_three_regions2),310 KUNIT_CASE(damon_test_apply_three_regions3),311 KUNIT_CASE(damon_test_apply_three_regions4),312 KUNIT_CASE(damon_test_split_evenly),313 {},314};315 316static struct kunit_suite damon_test_suite = {317 .name = "damon-operations",318 .test_cases = damon_test_cases,319};320kunit_test_suite(damon_test_suite);321 322#endif /* _DAMON_VADDR_TEST_H */323 324#endif /* CONFIG_DAMON_VADDR_KUNIT_TEST */325