tools/testing/selftests/kvm/lib/test_util.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * tools/testing/selftests/kvm/lib/test_util.c
   4  *
   5  * Copyright (C) 2020, Google LLC.
   6  */
   7
   8 #include <assert.h>
   9 #include <ctype.h>
  10 #include <limits.h>
  11 #include <stdlib.h>
  12 #include <time.h>
  13 #include <sys/stat.h>
  14 #include <sys/syscall.h>
  15 #include <linux/mman.h>
  16 #include "linux/kernel.h"
  17
  18 #include "test_util.h"
  19
  20 /*
  21  * Parses "[0-9]+[kmgt]?".
  22  */
  23 size_t parse_size(const char *size)
  24 {
  25         size_t base;
  26         char *scale;
  27         int shift = 0;
  28
  29         TEST_ASSERT(size && isdigit(size[0]), "Need at least one digit in '%s'", size);
  30
  31         base = strtoull(size, &scale, 0);
  32
  33         TEST_ASSERT(base != ULLONG_MAX, "Overflow parsing size!");
  34
  35         switch (tolower(*scale)) {
  36         case 't':
  37                 shift = 40;
  38                 break;
  39         case 'g':
  40                 shift = 30;
  41                 break;
  42         case 'm':
  43                 shift = 20;
  44                 break;
  45         case 'k':
  46                 shift = 10;
  47                 break;
  48         case 'b':
  49         case '\0':
  50                 shift = 0;
  51                 break;
  52         default:
  53                 TEST_ASSERT(false, "Unknown size letter %c", *scale);
  54         }
  55
  56         TEST_ASSERT((base << shift) >> shift == base, "Overflow scaling size!");
  57
  58         return base << shift;
  59 }
  60
  61 int64_t timespec_to_ns(struct timespec ts)
  62 {
  63         return (int64_t)ts.tv_nsec + 1000000000LL * (int64_t)ts.tv_sec;
  64 }
  65
  66 struct timespec timespec_add_ns(struct timespec ts, int64_t ns)
  67 {
  68         struct timespec res;
  69
  70         res.tv_nsec = ts.tv_nsec + ns;
  71         res.tv_sec = ts.tv_sec + res.tv_nsec / 1000000000LL;
  72         res.tv_nsec %= 1000000000LL;
  73
  74         return res;
  75 }
  76
  77 struct timespec timespec_add(struct timespec ts1, struct timespec ts2)
  78 {
  79         int64_t ns1 = timespec_to_ns(ts1);
  80         int64_t ns2 = timespec_to_ns(ts2);
  81         return timespec_add_ns((struct timespec){0}, ns1 + ns2);
  82 }
  83
  84 struct timespec timespec_sub(struct timespec ts1, struct timespec ts2)
  85 {
  86         int64_t ns1 = timespec_to_ns(ts1);
  87         int64_t ns2 = timespec_to_ns(ts2);
  88         return timespec_add_ns((struct timespec){0}, ns1 - ns2);
  89 }
  90
  91 struct timespec timespec_elapsed(struct timespec start)
  92 {
  93         struct timespec end;
  94
  95         clock_gettime(CLOCK_MONOTONIC, &end);
  96         return timespec_sub(end, start);
  97 }
  98
  99 struct timespec timespec_div(struct timespec ts, int divisor)
 100 {
 101         int64_t ns = timespec_to_ns(ts) / divisor;
 102
 103         return timespec_add_ns((struct timespec){0}, ns);
 104 }
 105
 106 void print_skip(const char *fmt, ...)
 107 {
 108         va_list ap;
 109
 110         assert(fmt);
 111         va_start(ap, fmt);
 112         vprintf(fmt, ap);
 113         va_end(ap);
 114         puts(", skipping test");
 115 }
 116
 117 bool thp_configured(void)
 118 {
 119         int ret;
 120         struct stat statbuf;
 121
 122         ret = stat("/sys/kernel/mm/transparent_hugepage", &statbuf);
 123         TEST_ASSERT(ret == 0 || (ret == -1 && errno == ENOENT),
 124                     "Error in stating /sys/kernel/mm/transparent_hugepage");
 125
 126         return ret == 0;
 127 }
 128
 129 size_t get_trans_hugepagesz(void)
 130 {
 131         size_t size;
 132         FILE *f;
 133         int ret;
 134
 135         TEST_ASSERT(thp_configured(), "THP is not configured in host kernel");
 136
 137         f = fopen("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", "r");
 138         TEST_ASSERT(f != NULL, "Error in opening transparent_hugepage/hpage_pmd_size");
 139
 140         ret = fscanf(f, "%ld", &size);
 141         ret = fscanf(f, "%ld", &size);
 142         TEST_ASSERT(ret < 1, "Error reading transparent_hugepage/hpage_pmd_size");
 143         fclose(f);
 144
 145         return size;
 146 }
 147
 148 size_t get_def_hugetlb_pagesz(void)
 149 {
 150         char buf[64];
 151         const char *tag = "Hugepagesize:";
 152         FILE *f;
 153
 154         f = fopen("/proc/meminfo", "r");
 155         TEST_ASSERT(f != NULL, "Error in opening /proc/meminfo");
 156
 157         while (fgets(buf, sizeof(buf), f) != NULL) {
 158                 if (strstr(buf, tag) == buf) {
 159                         fclose(f);
 160                         return strtoull(buf + strlen(tag), NULL, 10) << 10;
 161                 }
 162         }
 163
 164         if (feof(f))
 165                 TEST_FAIL("HUGETLB is not configured in host kernel");
 166         else
 167                 TEST_FAIL("Error in reading /proc/meminfo");
 168
 169         fclose(f);
 170         return 0;
 171 }
 172
 173 #define ANON_FLAGS      (MAP_PRIVATE | MAP_ANONYMOUS)
 174 #define ANON_HUGE_FLAGS (ANON_FLAGS | MAP_HUGETLB)
 175
 176 const struct vm_mem_backing_src_alias *vm_mem_backing_src_alias(uint32_t i)
 177 {
 178         static const struct vm_mem_backing_src_alias aliases[] = {
 179                 [VM_MEM_SRC_ANONYMOUS] = {
 180                         .name = "anonymous",
 181                         .flag = ANON_FLAGS,
 182                 },
 183                 [VM_MEM_SRC_ANONYMOUS_THP] = {
 184                         .name = "anonymous_thp",
 185                         .flag = ANON_FLAGS,
 186                 },
 187                 [VM_MEM_SRC_ANONYMOUS_HUGETLB] = {
 188                         .name = "anonymous_hugetlb",
 189                         .flag = ANON_HUGE_FLAGS,
 190                 },
 191                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_16KB] = {
 192                         .name = "anonymous_hugetlb_16kb",
 193                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_16KB,
 194                 },
 195                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_64KB] = {
 196                         .name = "anonymous_hugetlb_64kb",
 197                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_64KB,
 198                 },
 199                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_512KB] = {
 200                         .name = "anonymous_hugetlb_512kb",
 201                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_512KB,
 202                 },
 203                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_1MB] = {
 204                         .name = "anonymous_hugetlb_1mb",
 205                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_1MB,
 206                 },
 207                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_2MB] = {
 208                         .name = "anonymous_hugetlb_2mb",
 209                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_2MB,
 210                 },
 211                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_8MB] = {
 212                         .name = "anonymous_hugetlb_8mb",
 213                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_8MB,
 214                 },
 215                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_16MB] = {
 216                         .name = "anonymous_hugetlb_16mb",
 217                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_16MB,
 218                 },
 219                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_32MB] = {
 220                         .name = "anonymous_hugetlb_32mb",
 221                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_32MB,
 222                 },
 223                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_256MB] = {
 224                         .name = "anonymous_hugetlb_256mb",
 225                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_256MB,
 226                 },
 227                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_512MB] = {
 228                         .name = "anonymous_hugetlb_512mb",
 229                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_512MB,
 230                 },
 231                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_1GB] = {
 232                         .name = "anonymous_hugetlb_1gb",
 233                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_1GB,
 234                 },
 235                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_2GB] = {
 236                         .name = "anonymous_hugetlb_2gb",
 237                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_2GB,
 238                 },
 239                 [VM_MEM_SRC_ANONYMOUS_HUGETLB_16GB] = {
 240                         .name = "anonymous_hugetlb_16gb",
 241                         .flag = ANON_HUGE_FLAGS | MAP_HUGE_16GB,
 242                 },
 243                 [VM_MEM_SRC_SHMEM] = {
 244                         .name = "shmem",
 245                         .flag = MAP_SHARED,
 246                 },
 247                 [VM_MEM_SRC_SHARED_HUGETLB] = {
 248                         .name = "shared_hugetlb",
 249                         /*
 250                          * No MAP_HUGETLB, we use MFD_HUGETLB instead. Since
 251                          * we're using "file backed" memory, we need to specify
 252                          * this when the FD is created, not when the area is
 253                          * mapped.
 254                          */
 255                         .flag = MAP_SHARED,
 256                 },
 257         };
 258         _Static_assert(ARRAY_SIZE(aliases) == NUM_SRC_TYPES,
 259                        "Missing new backing src types?");
 260
 261         TEST_ASSERT(i < NUM_SRC_TYPES, "Backing src type ID %d too big", i);
 262
 263         return &aliases[i];
 264 }
 265
 266 #define MAP_HUGE_PAGE_SIZE(x) (1ULL << ((x >> MAP_HUGE_SHIFT) & MAP_HUGE_MASK))
 267
 268 size_t get_backing_src_pagesz(uint32_t i)
 269 {
 270         uint32_t flag = vm_mem_backing_src_alias(i)->flag;
 271
 272         switch (i) {
 273         case VM_MEM_SRC_ANONYMOUS:
 274         case VM_MEM_SRC_SHMEM:
 275                 return getpagesize();
 276         case VM_MEM_SRC_ANONYMOUS_THP:
 277                 return get_trans_hugepagesz();
 278         case VM_MEM_SRC_ANONYMOUS_HUGETLB:
 279         case VM_MEM_SRC_SHARED_HUGETLB:
 280                 return get_def_hugetlb_pagesz();
 281         default:
 282                 return MAP_HUGE_PAGE_SIZE(flag);
 283         }
 284 }
 285
 286 static void print_available_backing_src_types(const char *prefix)
 287 {
 288         int i;
 289
 290         printf("%sAvailable backing src types:\n", prefix);
 291
 292         for (i = 0; i < NUM_SRC_TYPES; i++)
 293                 printf("%s    %s\n", prefix, vm_mem_backing_src_alias(i)->name);
 294 }
 295
 296 void backing_src_help(const char *flag)
 297 {
 298         printf(" %s: specify the type of memory that should be used to\n"
 299                "     back the guest data region. (default: %s)\n",
 300                flag, vm_mem_backing_src_alias(DEFAULT_VM_MEM_SRC)->name);
 301         print_available_backing_src_types("     ");
 302 }
 303
 304 enum vm_mem_backing_src_type parse_backing_src_type(const char *type_name)
 305 {
 306         int i;
 307
 308         for (i = 0; i < NUM_SRC_TYPES; i++)
 309                 if (!strcmp(type_name, vm_mem_backing_src_alias(i)->name))
 310                         return i;
 311
 312         print_available_backing_src_types("");
 313         TEST_FAIL("Unknown backing src type: %s", type_name);
 314         return -1;
 315 }
 316
 317 long get_run_delay(void)
 318 {
 319         char path[64];
 320         long val[2];
 321         FILE *fp;
 322
 323         sprintf(path, "/proc/%ld/schedstat", syscall(SYS_gettid));
 324         fp = fopen(path, "r");
 325         /* Return MIN_RUN_DELAY_NS upon failure just to be safe */
 326         if (fscanf(fp, "%ld %ld ", &val[0], &val[1]) < 2)
 327                 val[1] = MIN_RUN_DELAY_NS;
 328         fclose(fp);
 329
 330         return val[1];
 331 }