Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2013 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include <errno.h> |
| 18 | #include <stdbool.h> |
| 19 | #include <stdlib.h> |
| 20 | #include <sys/types.h> |
| 21 | #include <unistd.h> |
| 22 | #include <string.h> |
| 23 | #include <fcntl.h> |
| 24 | #include <stdint.h> |
| 25 | #include <getopt.h> |
| 26 | |
| 27 | #include <pagemap/pagemap.h> |
| 28 | |
| 29 | #define MAX_FILENAME 64 |
| 30 | |
| 31 | #define GROWTH_FACTOR 10 |
| 32 | |
| 33 | #define NO_PATTERN 0x100 |
| 34 | |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 35 | #define PR_SORTED 1 |
| 36 | #define PR_VERBOSE 2 |
| 37 | |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 38 | static void usage(char *myname); |
| 39 | static int getprocname(pid_t pid, char *buf, int len); |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 40 | static void print_ksm_pages(pm_map_t **maps, size_t num_maps, uint8_t pr_flags); |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 41 | static bool is_pattern(uint8_t *data, size_t len); |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 42 | static int cmp_pages(const void *a, const void *b); |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 43 | extern uint32_t hashword(const uint32_t *, size_t, int32_t); |
| 44 | |
| 45 | struct ksm_page { |
| 46 | uint32_t hash; |
| 47 | unsigned long *vaddr; |
| 48 | size_t vaddr_len, vaddr_size; |
| 49 | uint16_t pattern; |
| 50 | }; |
| 51 | |
| 52 | int main(int argc, char *argv[]) { |
| 53 | pm_kernel_t *ker; |
| 54 | pm_process_t *proc; |
| 55 | pid_t pid; |
| 56 | pm_map_t **maps; |
| 57 | size_t num_maps; |
| 58 | char cmdline[256]; // this must be within the range of int |
| 59 | int error; |
| 60 | int rc = EXIT_SUCCESS; |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 61 | uint8_t pr_flags = 0; |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 62 | |
| 63 | opterr = 0; |
| 64 | do { |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 65 | int c = getopt(argc, argv, "hvs"); |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 66 | if (c == -1) |
| 67 | break; |
| 68 | |
| 69 | switch (c) { |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 70 | case 's': |
| 71 | pr_flags |= PR_SORTED; |
| 72 | break; |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 73 | case 'v': |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 74 | pr_flags |= PR_VERBOSE; |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 75 | break; |
| 76 | case 'h': |
| 77 | usage(argv[0]); |
| 78 | exit(EXIT_SUCCESS); |
| 79 | case '?': |
| 80 | fprintf(stderr, "unknown option: %c\n", optopt); |
| 81 | usage(argv[0]); |
| 82 | exit(EXIT_FAILURE); |
| 83 | } |
| 84 | } while (1); |
| 85 | |
| 86 | if (optind != argc - 1) { |
| 87 | usage(argv[0]); |
| 88 | exit(EXIT_FAILURE); |
| 89 | } |
| 90 | |
| 91 | pid = strtoul(argv[optind], NULL, 10); |
| 92 | if (pid == 0) { |
| 93 | fprintf(stderr, "Invalid PID\n"); |
| 94 | exit(EXIT_FAILURE); |
| 95 | } |
| 96 | |
| 97 | error = pm_kernel_create(&ker); |
| 98 | if (error) { |
| 99 | fprintf(stderr, "Error creating kernel interface -- " |
| 100 | "does this kernel have pagemap?\n"); |
| 101 | exit(EXIT_FAILURE); |
| 102 | } |
| 103 | |
| 104 | error = pm_process_create(ker, pid, &proc); |
| 105 | if (error) { |
| 106 | fprintf(stderr, "warning: could not create process interface for %d\n", pid); |
| 107 | exit(EXIT_FAILURE); |
| 108 | } |
| 109 | |
| 110 | error = pm_process_maps(proc, &maps, &num_maps); |
| 111 | if (error) { |
| 112 | fprintf(stderr, "warning: could not read process map for %d\n", pid); |
| 113 | rc = EXIT_FAILURE; |
| 114 | goto destroy_proc; |
| 115 | } |
| 116 | |
| 117 | if (getprocname(pid, cmdline, sizeof(cmdline)) < 0) { |
| 118 | cmdline[0] = '\0'; |
| 119 | } |
| 120 | printf("%s (%u):\n", cmdline, pid); |
| 121 | printf("Warning: this tool only compares the KSM CRCs of pages, there is a chance of " |
| 122 | "collisions\n"); |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 123 | print_ksm_pages(maps, num_maps, pr_flags); |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 124 | |
| 125 | free(maps); |
| 126 | destroy_proc: |
| 127 | pm_process_destroy(proc); |
| 128 | return rc; |
| 129 | } |
| 130 | |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 131 | static void print_ksm_pages(pm_map_t **maps, size_t num_maps, uint8_t pr_flags) { |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 132 | size_t i, j, k; |
| 133 | size_t len; |
| 134 | uint64_t *pagemap; |
| 135 | size_t map_len; |
| 136 | uint64_t flags; |
| 137 | pm_kernel_t *ker; |
| 138 | int error; |
| 139 | unsigned long vaddr; |
| 140 | int fd; |
| 141 | off_t off; |
| 142 | char filename[MAX_FILENAME]; |
| 143 | uint32_t *data; |
| 144 | uint32_t hash; |
| 145 | struct ksm_page *pages; |
| 146 | size_t pages_len, pages_size; |
| 147 | |
| 148 | if (num_maps <= 0) |
| 149 | return; |
| 150 | |
| 151 | ker = maps[0]->proc->ker; |
| 152 | error = snprintf(filename, MAX_FILENAME, "/proc/%d/mem", pm_process_pid(maps[0]->proc)); |
| 153 | if (error < 0 || error >= MAX_FILENAME) { |
| 154 | return; |
| 155 | } |
| 156 | |
| 157 | data = malloc(pm_kernel_pagesize(ker)); |
| 158 | if (data == NULL) { |
| 159 | fprintf(stderr, "warning: not enough memory to malloc data buffer\n"); |
| 160 | return; |
| 161 | } |
| 162 | |
| 163 | fd = open(filename, O_RDONLY); |
| 164 | if (fd < 0) { |
| 165 | fprintf(stderr, "warning: could not open %s\n", filename); |
| 166 | goto err_open; |
| 167 | } |
| 168 | |
| 169 | pages = NULL; |
| 170 | pages_size = 0; |
| 171 | pages_len = 0; |
| 172 | |
| 173 | for (i = 0; i < num_maps; i++) { |
| 174 | error = pm_map_pagemap(maps[i], &pagemap, &map_len); |
| 175 | if (error) { |
| 176 | fprintf(stderr, "warning: could not read the pagemap of %d\n", |
| 177 | pm_process_pid(maps[i]->proc)); |
| 178 | } |
| 179 | for (j = 0; j < map_len; j++) { |
| 180 | error = pm_kernel_flags(ker, pagemap[j], &flags); |
| 181 | if (error) { |
| 182 | fprintf(stderr, "warning: could not read flags for pfn at address 0x%016llx\n", |
| 183 | pagemap[i]); |
| 184 | continue; |
| 185 | } |
| 186 | if (!(flags & PM_PAGE_KSM)) { |
| 187 | continue; |
| 188 | } |
| 189 | vaddr = pm_map_start(maps[i]) + j * pm_kernel_pagesize(ker); |
| 190 | off = lseek(fd, vaddr, SEEK_SET); |
| 191 | if (off == (off_t)-1) { |
| 192 | fprintf(stderr, "warning: could not lseek to 0x%08lx\n", vaddr); |
| 193 | continue; |
| 194 | } |
| 195 | len = read(fd, data, pm_kernel_pagesize(ker)); |
| 196 | if (len != pm_kernel_pagesize(ker)) { |
| 197 | fprintf(stderr, "warning: could not read page at 0x%08lx\n", vaddr); |
| 198 | continue; |
| 199 | } |
| 200 | |
| 201 | hash = hashword(data, pm_kernel_pagesize(ker) / sizeof(*data), 17); |
| 202 | |
| 203 | for (k = 0; k < pages_len; k++) { |
| 204 | if (pages[k].hash == hash) break; |
| 205 | } |
| 206 | |
| 207 | if (k == pages_len) { |
| 208 | if (pages_len == pages_size) { |
| 209 | struct ksm_page *tmp = realloc(pages, |
| 210 | (pages_size + GROWTH_FACTOR) * sizeof(*pages)); |
| 211 | if (tmp == NULL) { |
| 212 | fprintf(stderr, "warning: not enough memory to realloc pages struct\n"); |
| 213 | free(pagemap); |
| 214 | goto err_realloc; |
| 215 | } |
| 216 | memset(&tmp[k], 0, sizeof(tmp[k]) * GROWTH_FACTOR); |
| 217 | pages = tmp; |
| 218 | pages_size += GROWTH_FACTOR; |
| 219 | } |
| 220 | pages[pages_len].hash = hash; |
| 221 | pages[pages_len].pattern = is_pattern((uint8_t *)data, pm_kernel_pagesize(ker)) ? |
| 222 | (data[0] & 0xFF) : NO_PATTERN; |
| 223 | pages_len++; |
| 224 | } |
| 225 | |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 226 | if (pr_flags & PR_VERBOSE) { |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 227 | if (pages[k].vaddr_len == pages[k].vaddr_size) { |
| 228 | unsigned long *tmp = realloc(pages[k].vaddr, |
| 229 | (pages[k].vaddr_size + GROWTH_FACTOR) * sizeof(*(pages[k].vaddr))); |
| 230 | if (tmp == NULL) { |
| 231 | fprintf(stderr, "warning: not enough memory to realloc vaddr array\n"); |
| 232 | free(pagemap); |
| 233 | goto err_realloc; |
| 234 | } |
| 235 | memset(&tmp[pages[k].vaddr_len], 0, sizeof(tmp[pages[k].vaddr_len]) * GROWTH_FACTOR); |
| 236 | pages[k].vaddr = tmp; |
| 237 | pages[k].vaddr_size += GROWTH_FACTOR; |
| 238 | } |
| 239 | pages[k].vaddr[pages[k].vaddr_len] = vaddr; |
| 240 | } |
| 241 | pages[k].vaddr_len++; |
| 242 | } |
| 243 | free(pagemap); |
| 244 | } |
| 245 | |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 246 | if (pr_flags & PR_SORTED) { |
| 247 | qsort(pages, pages_len, sizeof(*pages), cmp_pages); |
| 248 | } |
| 249 | |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 250 | for (i = 0; i < pages_len; i++) { |
| 251 | if (pages[i].pattern != NO_PATTERN) { |
| 252 | printf("0x%02x byte pattern: ", pages[i].pattern); |
| 253 | } else { |
| 254 | printf("KSM CRC 0x%08x:", pages[i].hash); |
| 255 | } |
| 256 | printf(" %4d page", pages[i].vaddr_len); |
| 257 | if (pages[i].vaddr_len > 1) { |
| 258 | printf("s"); |
| 259 | } |
| 260 | printf("\n"); |
| 261 | |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 262 | if (pr_flags & PR_VERBOSE) { |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 263 | j = 0; |
| 264 | while (j < pages[i].vaddr_len) { |
| 265 | printf(" "); |
| 266 | for (k = 0; k < 8 && j < pages[i].vaddr_len; k++, j++) { |
| 267 | printf(" 0x%08lx", pages[i].vaddr[j]); |
| 268 | } |
| 269 | printf("\n"); |
| 270 | } |
| 271 | } |
| 272 | } |
| 273 | |
| 274 | err_realloc: |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 275 | if (pr_flags & PR_VERBOSE) { |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 276 | for (i = 0; i < pages_len; i++) { |
| 277 | free(pages[i].vaddr); |
| 278 | } |
| 279 | } |
| 280 | free(pages); |
| 281 | err_pages: |
| 282 | close(fd); |
| 283 | err_open: |
| 284 | free(data); |
| 285 | } |
| 286 | |
| 287 | static void usage(char *myname) { |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 288 | fprintf(stderr, "Usage: %s [-s | -v | -h ] <pid>\n" |
| 289 | " -s Sort pages by usage count.\n" |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 290 | " -v Verbose: print virtual addresses.\n" |
| 291 | " -h Display this help screen.\n", |
| 292 | myname); |
| 293 | } |
| 294 | |
Rom Lemarchand | 2bed155 | 2013-07-08 21:50:24 -0700 | [diff] [blame^] | 295 | static int cmp_pages(const void *a, const void *b) { |
| 296 | const struct ksm_page *pg_a = a; |
| 297 | const struct ksm_page *pg_b = b; |
| 298 | |
| 299 | return pg_b->vaddr_len - pg_a->vaddr_len; |
| 300 | } |
| 301 | |
Rom Lemarchand | 266dde2 | 2013-07-08 15:22:10 -0700 | [diff] [blame] | 302 | static bool is_pattern(uint8_t *data, size_t len) { |
| 303 | size_t i; |
| 304 | uint8_t first_byte = data[0]; |
| 305 | |
| 306 | for (i = 1; i < len; i++) { |
| 307 | if (first_byte != data[i]) return false; |
| 308 | } |
| 309 | |
| 310 | return true; |
| 311 | } |
| 312 | |
| 313 | /* |
| 314 | * Get the process name for a given PID. Inserts the process name into buffer |
| 315 | * buf of length len. The size of the buffer must be greater than zero to get |
| 316 | * any useful output. |
| 317 | * |
| 318 | * Note that fgets(3) only declares length as an int, so our buffer size is |
| 319 | * also declared as an int. |
| 320 | * |
| 321 | * Returns 0 on success, a positive value on partial success, and -1 on |
| 322 | * failure. Other interesting values: |
| 323 | * 1 on failure to create string to examine proc cmdline entry |
| 324 | * 2 on failure to open proc cmdline entry |
| 325 | * 3 on failure to read proc cmdline entry |
| 326 | */ |
| 327 | static int getprocname(pid_t pid, char *buf, int len) { |
| 328 | char *filename; |
| 329 | FILE *f; |
| 330 | int rc = 0; |
| 331 | static const char* unknown_cmdline = "<unknown>"; |
| 332 | |
| 333 | if (len <= 0) { |
| 334 | return -1; |
| 335 | } |
| 336 | |
| 337 | if (asprintf(&filename, "/proc/%zd/cmdline", pid) < 0) { |
| 338 | rc = 1; |
| 339 | goto exit; |
| 340 | } |
| 341 | |
| 342 | f = fopen(filename, "r"); |
| 343 | if (f == NULL) { |
| 344 | rc = 2; |
| 345 | goto releasefilename; |
| 346 | } |
| 347 | |
| 348 | if (fgets(buf, len, f) == NULL) { |
| 349 | rc = 3; |
| 350 | goto closefile; |
| 351 | } |
| 352 | |
| 353 | closefile: |
| 354 | (void) fclose(f); |
| 355 | releasefilename: |
| 356 | free(filename); |
| 357 | exit: |
| 358 | if (rc != 0) { |
| 359 | /* |
| 360 | * The process went away before we could read its process name. Try |
| 361 | * to give the user "<unknown>" here, but otherwise they get to look |
| 362 | * at a blank. |
| 363 | */ |
| 364 | if (strlcpy(buf, unknown_cmdline, (size_t)len) >= (size_t)len) { |
| 365 | rc = 4; |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | return rc; |
| 370 | } |
| 371 | |