1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * DAMON sysfs Interface 4 * 5 * Copyright (c) 2022 SeongJae Park <sj@kernel.org> 6 */ 7 8 #include <linux/pid.h> 9 #include <linux/sched.h> 10 #include <linux/slab.h> 11 12 #include "sysfs-common.h" 13 14 /* 15 * init region directory 16 */ 17 18 struct damon_sysfs_region { 19 struct kobject kobj; 20 struct damon_addr_range ar; 21 }; 22 23 static struct damon_sysfs_region *damon_sysfs_region_alloc(void) 24 { 25 return kzalloc(sizeof(struct damon_sysfs_region), GFP_KERNEL); 26 } 27 28 static ssize_t start_show(struct kobject *kobj, struct kobj_attribute *attr, 29 char *buf) 30 { 31 struct damon_sysfs_region *region = container_of(kobj, 32 struct damon_sysfs_region, kobj); 33 34 return sysfs_emit(buf, "%lu\n", region->ar.start); 35 } 36 37 static ssize_t start_store(struct kobject *kobj, struct kobj_attribute *attr, 38 const char *buf, size_t count) 39 { 40 struct damon_sysfs_region *region = container_of(kobj, 41 struct damon_sysfs_region, kobj); 42 int err = kstrtoul(buf, 0, ®ion->ar.start); 43 44 return err ? err : count; 45 } 46 47 static ssize_t end_show(struct kobject *kobj, struct kobj_attribute *attr, 48 char *buf) 49 { 50 struct damon_sysfs_region *region = container_of(kobj, 51 struct damon_sysfs_region, kobj); 52 53 return sysfs_emit(buf, "%lu\n", region->ar.end); 54 } 55 56 static ssize_t end_store(struct kobject *kobj, struct kobj_attribute *attr, 57 const char *buf, size_t count) 58 { 59 struct damon_sysfs_region *region = container_of(kobj, 60 struct damon_sysfs_region, kobj); 61 int err = kstrtoul(buf, 0, ®ion->ar.end); 62 63 return err ? err : count; 64 } 65 66 static void damon_sysfs_region_release(struct kobject *kobj) 67 { 68 kfree(container_of(kobj, struct damon_sysfs_region, kobj)); 69 } 70 71 static struct kobj_attribute damon_sysfs_region_start_attr = 72 __ATTR_RW_MODE(start, 0600); 73 74 static struct kobj_attribute damon_sysfs_region_end_attr = 75 __ATTR_RW_MODE(end, 0600); 76 77 static struct attribute *damon_sysfs_region_attrs[] = { 78 &damon_sysfs_region_start_attr.attr, 79 &damon_sysfs_region_end_attr.attr, 80 NULL, 81 }; 82 ATTRIBUTE_GROUPS(damon_sysfs_region); 83 84 static const struct kobj_type damon_sysfs_region_ktype = { 85 .release = damon_sysfs_region_release, 86 .sysfs_ops = &kobj_sysfs_ops, 87 .default_groups = damon_sysfs_region_groups, 88 }; 89 90 /* 91 * init_regions directory 92 */ 93 94 struct damon_sysfs_regions { 95 struct kobject kobj; 96 struct damon_sysfs_region **regions_arr; 97 int nr; 98 }; 99 100 static struct damon_sysfs_regions *damon_sysfs_regions_alloc(void) 101 { 102 return kzalloc(sizeof(struct damon_sysfs_regions), GFP_KERNEL); 103 } 104 105 static void damon_sysfs_regions_rm_dirs(struct damon_sysfs_regions *regions) 106 { 107 struct damon_sysfs_region **regions_arr = regions->regions_arr; 108 int i; 109 110 for (i = 0; i < regions->nr; i++) 111 kobject_put(®ions_arr[i]->kobj); 112 regions->nr = 0; 113 kfree(regions_arr); 114 regions->regions_arr = NULL; 115 } 116 117 static int damon_sysfs_regions_add_dirs(struct damon_sysfs_regions *regions, 118 int nr_regions) 119 { 120 struct damon_sysfs_region **regions_arr, *region; 121 int err, i; 122 123 damon_sysfs_regions_rm_dirs(regions); 124 if (!nr_regions) 125 return 0; 126 127 regions_arr = kmalloc_array(nr_regions, sizeof(*regions_arr), 128 GFP_KERNEL | __GFP_NOWARN); 129 if (!regions_arr) 130 return -ENOMEM; 131 regions->regions_arr = regions_arr; 132 133 for (i = 0; i < nr_regions; i++) { 134 region = damon_sysfs_region_alloc(); 135 if (!region) { 136 damon_sysfs_regions_rm_dirs(regions); 137 return -ENOMEM; 138 } 139 140 err = kobject_init_and_add(®ion->kobj, 141 &damon_sysfs_region_ktype, ®ions->kobj, 142 "%d", i); 143 if (err) { 144 kobject_put(®ion->kobj); 145 damon_sysfs_regions_rm_dirs(regions); 146 return err; 147 } 148 149 regions_arr[i] = region; 150 regions->nr++; 151 } 152 return 0; 153 } 154 155 static ssize_t nr_regions_show(struct kobject *kobj, 156 struct kobj_attribute *attr, char *buf) 157 { 158 struct damon_sysfs_regions *regions = container_of(kobj, 159 struct damon_sysfs_regions, kobj); 160 161 return sysfs_emit(buf, "%d\n", regions->nr); 162 } 163 164 static ssize_t nr_regions_store(struct kobject *kobj, 165 struct kobj_attribute *attr, const char *buf, size_t count) 166 { 167 struct damon_sysfs_regions *regions; 168 int nr, err = kstrtoint(buf, 0, &nr); 169 170 if (err) 171 return err; 172 if (nr < 0) 173 return -EINVAL; 174 175 regions = container_of(kobj, struct damon_sysfs_regions, kobj); 176 177 if (!mutex_trylock(&damon_sysfs_lock)) 178 return -EBUSY; 179 err = damon_sysfs_regions_add_dirs(regions, nr); 180 mutex_unlock(&damon_sysfs_lock); 181 if (err) 182 return err; 183 184 return count; 185 } 186 187 static void damon_sysfs_regions_release(struct kobject *kobj) 188 { 189 kfree(container_of(kobj, struct damon_sysfs_regions, kobj)); 190 } 191 192 static struct kobj_attribute damon_sysfs_regions_nr_attr = 193 __ATTR_RW_MODE(nr_regions, 0600); 194 195 static struct attribute *damon_sysfs_regions_attrs[] = { 196 &damon_sysfs_regions_nr_attr.attr, 197 NULL, 198 }; 199 ATTRIBUTE_GROUPS(damon_sysfs_regions); 200 201 static const struct kobj_type damon_sysfs_regions_ktype = { 202 .release = damon_sysfs_regions_release, 203 .sysfs_ops = &kobj_sysfs_ops, 204 .default_groups = damon_sysfs_regions_groups, 205 }; 206 207 /* 208 * target directory 209 */ 210 211 struct damon_sysfs_target { 212 struct kobject kobj; 213 struct damon_sysfs_regions *regions; 214 int pid; 215 }; 216 217 static struct damon_sysfs_target *damon_sysfs_target_alloc(void) 218 { 219 return kzalloc(sizeof(struct damon_sysfs_target), GFP_KERNEL); 220 } 221 222 static int damon_sysfs_target_add_dirs(struct damon_sysfs_target *target) 223 { 224 struct damon_sysfs_regions *regions = damon_sysfs_regions_alloc(); 225 int err; 226 227 if (!regions) 228 return -ENOMEM; 229 230 err = kobject_init_and_add(®ions->kobj, &damon_sysfs_regions_ktype, 231 &target->kobj, "regions"); 232 if (err) 233 kobject_put(®ions->kobj); 234 else 235 target->regions = regions; 236 return err; 237 } 238 239 static void damon_sysfs_target_rm_dirs(struct damon_sysfs_target *target) 240 { 241 damon_sysfs_regions_rm_dirs(target->regions); 242 kobject_put(&target->regions->kobj); 243 } 244 245 static ssize_t pid_target_show(struct kobject *kobj, 246 struct kobj_attribute *attr, char *buf) 247 { 248 struct damon_sysfs_target *target = container_of(kobj, 249 struct damon_sysfs_target, kobj); 250 251 return sysfs_emit(buf, "%d\n", target->pid); 252 } 253 254 static ssize_t pid_target_store(struct kobject *kobj, 255 struct kobj_attribute *attr, const char *buf, size_t count) 256 { 257 struct damon_sysfs_target *target = container_of(kobj, 258 struct damon_sysfs_target, kobj); 259 int err = kstrtoint(buf, 0, &target->pid); 260 261 if (err) 262 return -EINVAL; 263 return count; 264 } 265 266 static void damon_sysfs_target_release(struct kobject *kobj) 267 { 268 kfree(container_of(kobj, struct damon_sysfs_target, kobj)); 269 } 270 271 static struct kobj_attribute damon_sysfs_target_pid_attr = 272 __ATTR_RW_MODE(pid_target, 0600); 273 274 static struct attribute *damon_sysfs_target_attrs[] = { 275 &damon_sysfs_target_pid_attr.attr, 276 NULL, 277 }; 278 ATTRIBUTE_GROUPS(damon_sysfs_target); 279 280 static const struct kobj_type damon_sysfs_target_ktype = { 281 .release = damon_sysfs_target_release, 282 .sysfs_ops = &kobj_sysfs_ops, 283 .default_groups = damon_sysfs_target_groups, 284 }; 285 286 /* 287 * targets directory 288 */ 289 290 struct damon_sysfs_targets { 291 struct kobject kobj; 292 struct damon_sysfs_target **targets_arr; 293 int nr; 294 }; 295 296 static struct damon_sysfs_targets *damon_sysfs_targets_alloc(void) 297 { 298 return kzalloc(sizeof(struct damon_sysfs_targets), GFP_KERNEL); 299 } 300 301 static void damon_sysfs_targets_rm_dirs(struct damon_sysfs_targets *targets) 302 { 303 struct damon_sysfs_target **targets_arr = targets->targets_arr; 304 int i; 305 306 for (i = 0; i < targets->nr; i++) { 307 damon_sysfs_target_rm_dirs(targets_arr[i]); 308 kobject_put(&targets_arr[i]->kobj); 309 } 310 targets->nr = 0; 311 kfree(targets_arr); 312 targets->targets_arr = NULL; 313 } 314 315 static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets, 316 int nr_targets) 317 { 318 struct damon_sysfs_target **targets_arr, *target; 319 int err, i; 320 321 damon_sysfs_targets_rm_dirs(targets); 322 if (!nr_targets) 323 return 0; 324 325 targets_arr = kmalloc_array(nr_targets, sizeof(*targets_arr), 326 GFP_KERNEL | __GFP_NOWARN); 327 if (!targets_arr) 328 return -ENOMEM; 329 targets->targets_arr = targets_arr; 330 331 for (i = 0; i < nr_targets; i++) { 332 target = damon_sysfs_target_alloc(); 333 if (!target) { 334 damon_sysfs_targets_rm_dirs(targets); 335 return -ENOMEM; 336 } 337 338 err = kobject_init_and_add(&target->kobj, 339 &damon_sysfs_target_ktype, &targets->kobj, 340 "%d", i); 341 if (err) 342 goto out; 343 344 err = damon_sysfs_target_add_dirs(target); 345 if (err) 346 goto out; 347 348 targets_arr[i] = target; 349 targets->nr++; 350 } 351 return 0; 352 353 out: 354 damon_sysfs_targets_rm_dirs(targets); 355 kobject_put(&target->kobj); 356 return err; 357 } 358 359 static ssize_t nr_targets_show(struct kobject *kobj, 360 struct kobj_attribute *attr, char *buf) 361 { 362 struct damon_sysfs_targets *targets = container_of(kobj, 363 struct damon_sysfs_targets, kobj); 364 365 return sysfs_emit(buf, "%d\n", targets->nr); 366 } 367 368 static ssize_t nr_targets_store(struct kobject *kobj, 369 struct kobj_attribute *attr, const char *buf, size_t count) 370 { 371 struct damon_sysfs_targets *targets; 372 int nr, err = kstrtoint(buf, 0, &nr); 373 374 if (err) 375 return err; 376 if (nr < 0) 377 return -EINVAL; 378 379 targets = container_of(kobj, struct damon_sysfs_targets, kobj); 380 381 if (!mutex_trylock(&damon_sysfs_lock)) 382 return -EBUSY; 383 err = damon_sysfs_targets_add_dirs(targets, nr); 384 mutex_unlock(&damon_sysfs_lock); 385 if (err) 386 return err; 387 388 return count; 389 } 390 391 static void damon_sysfs_targets_release(struct kobject *kobj) 392 { 393 kfree(container_of(kobj, struct damon_sysfs_targets, kobj)); 394 } 395 396 static struct kobj_attribute damon_sysfs_targets_nr_attr = 397 __ATTR_RW_MODE(nr_targets, 0600); 398 399 static struct attribute *damon_sysfs_targets_attrs[] = { 400 &damon_sysfs_targets_nr_attr.attr, 401 NULL, 402 }; 403 ATTRIBUTE_GROUPS(damon_sysfs_targets); 404 405 static const struct kobj_type damon_sysfs_targets_ktype = { 406 .release = damon_sysfs_targets_release, 407 .sysfs_ops = &kobj_sysfs_ops, 408 .default_groups = damon_sysfs_targets_groups, 409 }; 410 411 /* 412 * intervals directory 413 */ 414 415 struct damon_sysfs_intervals { 416 struct kobject kobj; 417 unsigned long sample_us; 418 unsigned long aggr_us; 419 unsigned long update_us; 420 }; 421 422 static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc( 423 unsigned long sample_us, unsigned long aggr_us, 424 unsigned long update_us) 425 { 426 struct damon_sysfs_intervals *intervals = kmalloc(sizeof(*intervals), 427 GFP_KERNEL); 428 429 if (!intervals) 430 return NULL; 431 432 intervals->kobj = (struct kobject){}; 433 intervals->sample_us = sample_us; 434 intervals->aggr_us = aggr_us; 435 intervals->update_us = update_us; 436 return intervals; 437 } 438 439 static ssize_t sample_us_show(struct kobject *kobj, 440 struct kobj_attribute *attr, char *buf) 441 { 442 struct damon_sysfs_intervals *intervals = container_of(kobj, 443 struct damon_sysfs_intervals, kobj); 444 445 return sysfs_emit(buf, "%lu\n", intervals->sample_us); 446 } 447 448 static ssize_t sample_us_store(struct kobject *kobj, 449 struct kobj_attribute *attr, const char *buf, size_t count) 450 { 451 struct damon_sysfs_intervals *intervals = container_of(kobj, 452 struct damon_sysfs_intervals, kobj); 453 unsigned long us; 454 int err = kstrtoul(buf, 0, &us); 455 456 if (err) 457 return err; 458 459 intervals->sample_us = us; 460 return count; 461 } 462 463 static ssize_t aggr_us_show(struct kobject *kobj, struct kobj_attribute *attr, 464 char *buf) 465 { 466 struct damon_sysfs_intervals *intervals = container_of(kobj, 467 struct damon_sysfs_intervals, kobj); 468 469 return sysfs_emit(buf, "%lu\n", intervals->aggr_us); 470 } 471 472 static ssize_t aggr_us_store(struct kobject *kobj, struct kobj_attribute *attr, 473 const char *buf, size_t count) 474 { 475 struct damon_sysfs_intervals *intervals = container_of(kobj, 476 struct damon_sysfs_intervals, kobj); 477 unsigned long us; 478 int err = kstrtoul(buf, 0, &us); 479 480 if (err) 481 return err; 482 483 intervals->aggr_us = us; 484 return count; 485 } 486 487 static ssize_t update_us_show(struct kobject *kobj, 488 struct kobj_attribute *attr, char *buf) 489 { 490 struct damon_sysfs_intervals *intervals = container_of(kobj, 491 struct damon_sysfs_intervals, kobj); 492 493 return sysfs_emit(buf, "%lu\n", intervals->update_us); 494 } 495 496 static ssize_t update_us_store(struct kobject *kobj, 497 struct kobj_attribute *attr, const char *buf, size_t count) 498 { 499 struct damon_sysfs_intervals *intervals = container_of(kobj, 500 struct damon_sysfs_intervals, kobj); 501 unsigned long us; 502 int err = kstrtoul(buf, 0, &us); 503 504 if (err) 505 return err; 506 507 intervals->update_us = us; 508 return count; 509 } 510 511 static void damon_sysfs_intervals_release(struct kobject *kobj) 512 { 513 kfree(container_of(kobj, struct damon_sysfs_intervals, kobj)); 514 } 515 516 static struct kobj_attribute damon_sysfs_intervals_sample_us_attr = 517 __ATTR_RW_MODE(sample_us, 0600); 518 519 static struct kobj_attribute damon_sysfs_intervals_aggr_us_attr = 520 __ATTR_RW_MODE(aggr_us, 0600); 521 522 static struct kobj_attribute damon_sysfs_intervals_update_us_attr = 523 __ATTR_RW_MODE(update_us, 0600); 524 525 static struct attribute *damon_sysfs_intervals_attrs[] = { 526 &damon_sysfs_intervals_sample_us_attr.attr, 527 &damon_sysfs_intervals_aggr_us_attr.attr, 528 &damon_sysfs_intervals_update_us_attr.attr, 529 NULL, 530 }; 531 ATTRIBUTE_GROUPS(damon_sysfs_intervals); 532 533 static const struct kobj_type damon_sysfs_intervals_ktype = { 534 .release = damon_sysfs_intervals_release, 535 .sysfs_ops = &kobj_sysfs_ops, 536 .default_groups = damon_sysfs_intervals_groups, 537 }; 538 539 /* 540 * monitoring_attrs directory 541 */ 542 543 struct damon_sysfs_attrs { 544 struct kobject kobj; 545 struct damon_sysfs_intervals *intervals; 546 struct damon_sysfs_ul_range *nr_regions_range; 547 }; 548 549 static struct damon_sysfs_attrs *damon_sysfs_attrs_alloc(void) 550 { 551 struct damon_sysfs_attrs *attrs = kmalloc(sizeof(*attrs), GFP_KERNEL); 552 553 if (!attrs) 554 return NULL; 555 attrs->kobj = (struct kobject){}; 556 return attrs; 557 } 558 559 static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs) 560 { 561 struct damon_sysfs_intervals *intervals; 562 struct damon_sysfs_ul_range *nr_regions_range; 563 int err; 564 565 intervals = damon_sysfs_intervals_alloc(5000, 100000, 60000000); 566 if (!intervals) 567 return -ENOMEM; 568 569 err = kobject_init_and_add(&intervals->kobj, 570 &damon_sysfs_intervals_ktype, &attrs->kobj, 571 "intervals"); 572 if (err) 573 goto put_intervals_out; 574 attrs->intervals = intervals; 575 576 nr_regions_range = damon_sysfs_ul_range_alloc(10, 1000); 577 if (!nr_regions_range) { 578 err = -ENOMEM; 579 goto put_intervals_out; 580 } 581 582 err = kobject_init_and_add(&nr_regions_range->kobj, 583 &damon_sysfs_ul_range_ktype, &attrs->kobj, 584 "nr_regions"); 585 if (err) 586 goto put_nr_regions_intervals_out; 587 attrs->nr_regions_range = nr_regions_range; 588 return 0; 589 590 put_nr_regions_intervals_out: 591 kobject_put(&nr_regions_range->kobj); 592 attrs->nr_regions_range = NULL; 593 put_intervals_out: 594 kobject_put(&intervals->kobj); 595 attrs->intervals = NULL; 596 return err; 597 } 598 599 static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs) 600 { 601 kobject_put(&attrs->nr_regions_range->kobj); 602 kobject_put(&attrs->intervals->kobj); 603 } 604 605 static void damon_sysfs_attrs_release(struct kobject *kobj) 606 { 607 kfree(container_of(kobj, struct damon_sysfs_attrs, kobj)); 608 } 609 610 static struct attribute *damon_sysfs_attrs_attrs[] = { 611 NULL, 612 }; 613 ATTRIBUTE_GROUPS(damon_sysfs_attrs); 614 615 static const struct kobj_type damon_sysfs_attrs_ktype = { 616 .release = damon_sysfs_attrs_release, 617 .sysfs_ops = &kobj_sysfs_ops, 618 .default_groups = damon_sysfs_attrs_groups, 619 }; 620 621 /* 622 * context directory 623 */ 624 625 /* This should match with enum damon_ops_id */ 626 static const char * const damon_sysfs_ops_strs[] = { 627 "vaddr", 628 "fvaddr", 629 "paddr", 630 }; 631 632 struct damon_sysfs_context { 633 struct kobject kobj; 634 enum damon_ops_id ops_id; 635 struct damon_sysfs_attrs *attrs; 636 struct damon_sysfs_targets *targets; 637 struct damon_sysfs_schemes *schemes; 638 }; 639 640 static struct damon_sysfs_context *damon_sysfs_context_alloc( 641 enum damon_ops_id ops_id) 642 { 643 struct damon_sysfs_context *context = kmalloc(sizeof(*context), 644 GFP_KERNEL); 645 646 if (!context) 647 return NULL; 648 context->kobj = (struct kobject){}; 649 context->ops_id = ops_id; 650 return context; 651 } 652 653 static int damon_sysfs_context_set_attrs(struct damon_sysfs_context *context) 654 { 655 struct damon_sysfs_attrs *attrs = damon_sysfs_attrs_alloc(); 656 int err; 657 658 if (!attrs) 659 return -ENOMEM; 660 err = kobject_init_and_add(&attrs->kobj, &damon_sysfs_attrs_ktype, 661 &context->kobj, "monitoring_attrs"); 662 if (err) 663 goto out; 664 err = damon_sysfs_attrs_add_dirs(attrs); 665 if (err) 666 goto out; 667 context->attrs = attrs; 668 return 0; 669 670 out: 671 kobject_put(&attrs->kobj); 672 return err; 673 } 674 675 static int damon_sysfs_context_set_targets(struct damon_sysfs_context *context) 676 { 677 struct damon_sysfs_targets *targets = damon_sysfs_targets_alloc(); 678 int err; 679 680 if (!targets) 681 return -ENOMEM; 682 err = kobject_init_and_add(&targets->kobj, &damon_sysfs_targets_ktype, 683 &context->kobj, "targets"); 684 if (err) { 685 kobject_put(&targets->kobj); 686 return err; 687 } 688 context->targets = targets; 689 return 0; 690 } 691 692 static int damon_sysfs_context_set_schemes(struct damon_sysfs_context *context) 693 { 694 struct damon_sysfs_schemes *schemes = damon_sysfs_schemes_alloc(); 695 int err; 696 697 if (!schemes) 698 return -ENOMEM; 699 err = kobject_init_and_add(&schemes->kobj, &damon_sysfs_schemes_ktype, 700 &context->kobj, "schemes"); 701 if (err) { 702 kobject_put(&schemes->kobj); 703 return err; 704 } 705 context->schemes = schemes; 706 return 0; 707 } 708 709 static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context) 710 { 711 int err; 712 713 err = damon_sysfs_context_set_attrs(context); 714 if (err) 715 return err; 716 717 err = damon_sysfs_context_set_targets(context); 718 if (err) 719 goto put_attrs_out; 720 721 err = damon_sysfs_context_set_schemes(context); 722 if (err) 723 goto put_targets_attrs_out; 724 return 0; 725 726 put_targets_attrs_out: 727 kobject_put(&context->targets->kobj); 728 context->targets = NULL; 729 put_attrs_out: 730 kobject_put(&context->attrs->kobj); 731 context->attrs = NULL; 732 return err; 733 } 734 735 static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context) 736 { 737 damon_sysfs_attrs_rm_dirs(context->attrs); 738 kobject_put(&context->attrs->kobj); 739 damon_sysfs_targets_rm_dirs(context->targets); 740 kobject_put(&context->targets->kobj); 741 damon_sysfs_schemes_rm_dirs(context->schemes); 742 kobject_put(&context->schemes->kobj); 743 } 744 745 static ssize_t avail_operations_show(struct kobject *kobj, 746 struct kobj_attribute *attr, char *buf) 747 { 748 enum damon_ops_id id; 749 int len = 0; 750 751 for (id = 0; id < NR_DAMON_OPS; id++) { 752 if (!damon_is_registered_ops(id)) 753 continue; 754 len += sysfs_emit_at(buf, len, "%s\n", 755 damon_sysfs_ops_strs[id]); 756 } 757 return len; 758 } 759 760 static ssize_t operations_show(struct kobject *kobj, 761 struct kobj_attribute *attr, char *buf) 762 { 763 struct damon_sysfs_context *context = container_of(kobj, 764 struct damon_sysfs_context, kobj); 765 766 return sysfs_emit(buf, "%s\n", damon_sysfs_ops_strs[context->ops_id]); 767 } 768 769 static ssize_t operations_store(struct kobject *kobj, 770 struct kobj_attribute *attr, const char *buf, size_t count) 771 { 772 struct damon_sysfs_context *context = container_of(kobj, 773 struct damon_sysfs_context, kobj); 774 enum damon_ops_id id; 775 776 for (id = 0; id < NR_DAMON_OPS; id++) { 777 if (sysfs_streq(buf, damon_sysfs_ops_strs[id])) { 778 context->ops_id = id; 779 return count; 780 } 781 } 782 return -EINVAL; 783 } 784 785 static void damon_sysfs_context_release(struct kobject *kobj) 786 { 787 kfree(container_of(kobj, struct damon_sysfs_context, kobj)); 788 } 789 790 static struct kobj_attribute damon_sysfs_context_avail_operations_attr = 791 __ATTR_RO_MODE(avail_operations, 0400); 792 793 static struct kobj_attribute damon_sysfs_context_operations_attr = 794 __ATTR_RW_MODE(operations, 0600); 795 796 static struct attribute *damon_sysfs_context_attrs[] = { 797 &damon_sysfs_context_avail_operations_attr.attr, 798 &damon_sysfs_context_operations_attr.attr, 799 NULL, 800 }; 801 ATTRIBUTE_GROUPS(damon_sysfs_context); 802 803 static const struct kobj_type damon_sysfs_context_ktype = { 804 .release = damon_sysfs_context_release, 805 .sysfs_ops = &kobj_sysfs_ops, 806 .default_groups = damon_sysfs_context_groups, 807 }; 808 809 /* 810 * contexts directory 811 */ 812 813 struct damon_sysfs_contexts { 814 struct kobject kobj; 815 struct damon_sysfs_context **contexts_arr; 816 int nr; 817 }; 818 819 static struct damon_sysfs_contexts *damon_sysfs_contexts_alloc(void) 820 { 821 return kzalloc(sizeof(struct damon_sysfs_contexts), GFP_KERNEL); 822 } 823 824 static void damon_sysfs_contexts_rm_dirs(struct damon_sysfs_contexts *contexts) 825 { 826 struct damon_sysfs_context **contexts_arr = contexts->contexts_arr; 827 int i; 828 829 for (i = 0; i < contexts->nr; i++) { 830 damon_sysfs_context_rm_dirs(contexts_arr[i]); 831 kobject_put(&contexts_arr[i]->kobj); 832 } 833 contexts->nr = 0; 834 kfree(contexts_arr); 835 contexts->contexts_arr = NULL; 836 } 837 838 static int damon_sysfs_contexts_add_dirs(struct damon_sysfs_contexts *contexts, 839 int nr_contexts) 840 { 841 struct damon_sysfs_context **contexts_arr, *context; 842 int err, i; 843 844 damon_sysfs_contexts_rm_dirs(contexts); 845 if (!nr_contexts) 846 return 0; 847 848 contexts_arr = kmalloc_array(nr_contexts, sizeof(*contexts_arr), 849 GFP_KERNEL | __GFP_NOWARN); 850 if (!contexts_arr) 851 return -ENOMEM; 852 contexts->contexts_arr = contexts_arr; 853 854 for (i = 0; i < nr_contexts; i++) { 855 context = damon_sysfs_context_alloc(DAMON_OPS_VADDR); 856 if (!context) { 857 damon_sysfs_contexts_rm_dirs(contexts); 858 return -ENOMEM; 859 } 860 861 err = kobject_init_and_add(&context->kobj, 862 &damon_sysfs_context_ktype, &contexts->kobj, 863 "%d", i); 864 if (err) 865 goto out; 866 867 err = damon_sysfs_context_add_dirs(context); 868 if (err) 869 goto out; 870 871 contexts_arr[i] = context; 872 contexts->nr++; 873 } 874 return 0; 875 876 out: 877 damon_sysfs_contexts_rm_dirs(contexts); 878 kobject_put(&context->kobj); 879 return err; 880 } 881 882 static ssize_t nr_contexts_show(struct kobject *kobj, 883 struct kobj_attribute *attr, char *buf) 884 { 885 struct damon_sysfs_contexts *contexts = container_of(kobj, 886 struct damon_sysfs_contexts, kobj); 887 888 return sysfs_emit(buf, "%d\n", contexts->nr); 889 } 890 891 static ssize_t nr_contexts_store(struct kobject *kobj, 892 struct kobj_attribute *attr, const char *buf, size_t count) 893 { 894 struct damon_sysfs_contexts *contexts; 895 int nr, err; 896 897 err = kstrtoint(buf, 0, &nr); 898 if (err) 899 return err; 900 /* TODO: support multiple contexts per kdamond */ 901 if (nr < 0 || 1 < nr) 902 return -EINVAL; 903 904 contexts = container_of(kobj, struct damon_sysfs_contexts, kobj); 905 if (!mutex_trylock(&damon_sysfs_lock)) 906 return -EBUSY; 907 err = damon_sysfs_contexts_add_dirs(contexts, nr); 908 mutex_unlock(&damon_sysfs_lock); 909 if (err) 910 return err; 911 912 return count; 913 } 914 915 static void damon_sysfs_contexts_release(struct kobject *kobj) 916 { 917 kfree(container_of(kobj, struct damon_sysfs_contexts, kobj)); 918 } 919 920 static struct kobj_attribute damon_sysfs_contexts_nr_attr 921 = __ATTR_RW_MODE(nr_contexts, 0600); 922 923 static struct attribute *damon_sysfs_contexts_attrs[] = { 924 &damon_sysfs_contexts_nr_attr.attr, 925 NULL, 926 }; 927 ATTRIBUTE_GROUPS(damon_sysfs_contexts); 928 929 static const struct kobj_type damon_sysfs_contexts_ktype = { 930 .release = damon_sysfs_contexts_release, 931 .sysfs_ops = &kobj_sysfs_ops, 932 .default_groups = damon_sysfs_contexts_groups, 933 }; 934 935 /* 936 * kdamond directory 937 */ 938 939 struct damon_sysfs_kdamond { 940 struct kobject kobj; 941 struct damon_sysfs_contexts *contexts; 942 struct damon_ctx *damon_ctx; 943 }; 944 945 static struct damon_sysfs_kdamond *damon_sysfs_kdamond_alloc(void) 946 { 947 return kzalloc(sizeof(struct damon_sysfs_kdamond), GFP_KERNEL); 948 } 949 950 static int damon_sysfs_kdamond_add_dirs(struct damon_sysfs_kdamond *kdamond) 951 { 952 struct damon_sysfs_contexts *contexts; 953 int err; 954 955 contexts = damon_sysfs_contexts_alloc(); 956 if (!contexts) 957 return -ENOMEM; 958 959 err = kobject_init_and_add(&contexts->kobj, 960 &damon_sysfs_contexts_ktype, &kdamond->kobj, 961 "contexts"); 962 if (err) { 963 kobject_put(&contexts->kobj); 964 return err; 965 } 966 kdamond->contexts = contexts; 967 968 return err; 969 } 970 971 static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond) 972 { 973 damon_sysfs_contexts_rm_dirs(kdamond->contexts); 974 kobject_put(&kdamond->contexts->kobj); 975 } 976 977 static bool damon_sysfs_ctx_running(struct damon_ctx *ctx) 978 { 979 bool running; 980 981 mutex_lock(&ctx->kdamond_lock); 982 running = ctx->kdamond != NULL; 983 mutex_unlock(&ctx->kdamond_lock); 984 return running; 985 } 986 987 /* 988 * enum damon_sysfs_cmd - Commands for a specific kdamond. 989 */ 990 enum damon_sysfs_cmd { 991 /* @DAMON_SYSFS_CMD_ON: Turn the kdamond on. */ 992 DAMON_SYSFS_CMD_ON, 993 /* @DAMON_SYSFS_CMD_OFF: Turn the kdamond off. */ 994 DAMON_SYSFS_CMD_OFF, 995 /* @DAMON_SYSFS_CMD_COMMIT: Update kdamond inputs. */ 996 DAMON_SYSFS_CMD_COMMIT, 997 /* 998 * @DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS: Commit the quota goals 999 * to DAMON. 1000 */ 1001 DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS, 1002 /* 1003 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: Update scheme stats sysfs 1004 * files. 1005 */ 1006 DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS, 1007 /* 1008 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: Update 1009 * tried_regions/total_bytes sysfs files for each scheme. 1010 */ 1011 DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES, 1012 /* 1013 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried 1014 * regions 1015 */ 1016 DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS, 1017 /* 1018 * @DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: Clear schemes tried 1019 * regions 1020 */ 1021 DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS, 1022 /* 1023 * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands. 1024 */ 1025 NR_DAMON_SYSFS_CMDS, 1026 }; 1027 1028 /* Should match with enum damon_sysfs_cmd */ 1029 static const char * const damon_sysfs_cmd_strs[] = { 1030 "on", 1031 "off", 1032 "commit", 1033 "commit_schemes_quota_goals", 1034 "update_schemes_stats", 1035 "update_schemes_tried_bytes", 1036 "update_schemes_tried_regions", 1037 "clear_schemes_tried_regions", 1038 }; 1039 1040 /* 1041 * struct damon_sysfs_cmd_request - A request to the DAMON callback. 1042 * @cmd: The command that needs to be handled by the callback. 1043 * @kdamond: The kobject wrapper that associated to the kdamond thread. 1044 * 1045 * This structure represents a sysfs command request that need to access some 1046 * DAMON context-internal data. Because DAMON context-internal data can be 1047 * safely accessed from DAMON callbacks without additional synchronization, the 1048 * request will be handled by the DAMON callback. None-``NULL`` @kdamond means 1049 * the request is valid. 1050 */ 1051 struct damon_sysfs_cmd_request { 1052 enum damon_sysfs_cmd cmd; 1053 struct damon_sysfs_kdamond *kdamond; 1054 }; 1055 1056 /* Current DAMON callback request. Protected by damon_sysfs_lock. */ 1057 static struct damon_sysfs_cmd_request damon_sysfs_cmd_request; 1058 1059 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, 1060 char *buf) 1061 { 1062 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1063 struct damon_sysfs_kdamond, kobj); 1064 struct damon_ctx *ctx = kdamond->damon_ctx; 1065 bool running; 1066 1067 if (!ctx) 1068 running = false; 1069 else 1070 running = damon_sysfs_ctx_running(ctx); 1071 1072 return sysfs_emit(buf, "%s\n", running ? 1073 damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] : 1074 damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_OFF]); 1075 } 1076 1077 static int damon_sysfs_set_attrs(struct damon_ctx *ctx, 1078 struct damon_sysfs_attrs *sys_attrs) 1079 { 1080 struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals; 1081 struct damon_sysfs_ul_range *sys_nr_regions = 1082 sys_attrs->nr_regions_range; 1083 struct damon_attrs attrs = { 1084 .sample_interval = sys_intervals->sample_us, 1085 .aggr_interval = sys_intervals->aggr_us, 1086 .ops_update_interval = sys_intervals->update_us, 1087 .min_nr_regions = sys_nr_regions->min, 1088 .max_nr_regions = sys_nr_regions->max, 1089 }; 1090 return damon_set_attrs(ctx, &attrs); 1091 } 1092 1093 static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) 1094 { 1095 struct damon_target *t, *next; 1096 bool has_pid = damon_target_has_pid(ctx); 1097 1098 damon_for_each_target_safe(t, next, ctx) { 1099 if (has_pid) 1100 put_pid(t->pid); 1101 damon_destroy_target(t); 1102 } 1103 } 1104 1105 static int damon_sysfs_set_regions(struct damon_target *t, 1106 struct damon_sysfs_regions *sysfs_regions) 1107 { 1108 struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr, 1109 sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN); 1110 int i, err = -EINVAL; 1111 1112 if (!ranges) 1113 return -ENOMEM; 1114 for (i = 0; i < sysfs_regions->nr; i++) { 1115 struct damon_sysfs_region *sys_region = 1116 sysfs_regions->regions_arr[i]; 1117 1118 if (sys_region->ar.start > sys_region->ar.end) 1119 goto out; 1120 1121 ranges[i].start = sys_region->ar.start; 1122 ranges[i].end = sys_region->ar.end; 1123 if (i == 0) 1124 continue; 1125 if (ranges[i - 1].end > ranges[i].start) 1126 goto out; 1127 } 1128 err = damon_set_regions(t, ranges, sysfs_regions->nr); 1129 out: 1130 kfree(ranges); 1131 return err; 1132 1133 } 1134 1135 static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target, 1136 struct damon_ctx *ctx) 1137 { 1138 struct damon_target *t = damon_new_target(); 1139 int err = -EINVAL; 1140 1141 if (!t) 1142 return -ENOMEM; 1143 damon_add_target(ctx, t); 1144 if (damon_target_has_pid(ctx)) { 1145 t->pid = find_get_pid(sys_target->pid); 1146 if (!t->pid) 1147 goto destroy_targets_out; 1148 } 1149 err = damon_sysfs_set_regions(t, sys_target->regions); 1150 if (err) 1151 goto destroy_targets_out; 1152 return 0; 1153 1154 destroy_targets_out: 1155 damon_sysfs_destroy_targets(ctx); 1156 return err; 1157 } 1158 1159 static int damon_sysfs_update_target_pid(struct damon_target *target, int pid) 1160 { 1161 struct pid *pid_new; 1162 1163 pid_new = find_get_pid(pid); 1164 if (!pid_new) 1165 return -EINVAL; 1166 1167 if (pid_new == target->pid) { 1168 put_pid(pid_new); 1169 return 0; 1170 } 1171 1172 put_pid(target->pid); 1173 target->pid = pid_new; 1174 return 0; 1175 } 1176 1177 static int damon_sysfs_update_target(struct damon_target *target, 1178 struct damon_ctx *ctx, 1179 struct damon_sysfs_target *sys_target) 1180 { 1181 int err = 0; 1182 1183 if (damon_target_has_pid(ctx)) { 1184 err = damon_sysfs_update_target_pid(target, sys_target->pid); 1185 if (err) 1186 return err; 1187 } 1188 1189 /* 1190 * Do monitoring target region boundary update only if one or more 1191 * regions are set by the user. This is for keeping current monitoring 1192 * target results and range easier, especially for dynamic monitoring 1193 * target regions update ops like 'vaddr'. 1194 */ 1195 if (sys_target->regions->nr) 1196 err = damon_sysfs_set_regions(target, sys_target->regions); 1197 return err; 1198 } 1199 1200 static int damon_sysfs_set_targets(struct damon_ctx *ctx, 1201 struct damon_sysfs_targets *sysfs_targets) 1202 { 1203 struct damon_target *t, *next; 1204 int i = 0, err; 1205 1206 /* Multiple physical address space monitoring targets makes no sense */ 1207 if (ctx->ops.id == DAMON_OPS_PADDR && sysfs_targets->nr > 1) 1208 return -EINVAL; 1209 1210 damon_for_each_target_safe(t, next, ctx) { 1211 if (i < sysfs_targets->nr) { 1212 err = damon_sysfs_update_target(t, ctx, 1213 sysfs_targets->targets_arr[i]); 1214 if (err) 1215 return err; 1216 } else { 1217 if (damon_target_has_pid(ctx)) 1218 put_pid(t->pid); 1219 damon_destroy_target(t); 1220 } 1221 i++; 1222 } 1223 1224 for (; i < sysfs_targets->nr; i++) { 1225 struct damon_sysfs_target *st = sysfs_targets->targets_arr[i]; 1226 1227 err = damon_sysfs_add_target(st, ctx); 1228 if (err) 1229 return err; 1230 } 1231 return 0; 1232 } 1233 1234 static bool damon_sysfs_schemes_regions_updating; 1235 1236 static void damon_sysfs_before_terminate(struct damon_ctx *ctx) 1237 { 1238 struct damon_target *t, *next; 1239 struct damon_sysfs_kdamond *kdamond; 1240 enum damon_sysfs_cmd cmd; 1241 1242 /* damon_sysfs_schemes_update_regions_stop() might not yet called */ 1243 kdamond = damon_sysfs_cmd_request.kdamond; 1244 cmd = damon_sysfs_cmd_request.cmd; 1245 if (kdamond && ctx == kdamond->damon_ctx && 1246 (cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS || 1247 cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES) && 1248 damon_sysfs_schemes_regions_updating) { 1249 damon_sysfs_schemes_update_regions_stop(ctx); 1250 damon_sysfs_schemes_regions_updating = false; 1251 mutex_unlock(&damon_sysfs_lock); 1252 } 1253 1254 if (!damon_target_has_pid(ctx)) 1255 return; 1256 1257 mutex_lock(&ctx->kdamond_lock); 1258 damon_for_each_target_safe(t, next, ctx) { 1259 put_pid(t->pid); 1260 damon_destroy_target(t); 1261 } 1262 mutex_unlock(&ctx->kdamond_lock); 1263 } 1264 1265 /* 1266 * damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files. 1267 * @kdamond: The kobject wrapper that associated to the kdamond thread. 1268 * 1269 * This function reads the schemes stats of specific kdamond and update the 1270 * related values for sysfs files. This function should be called from DAMON 1271 * callbacks while holding ``damon_syfs_lock``, to safely access the DAMON 1272 * contexts-internal data and DAMON sysfs variables. 1273 */ 1274 static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond) 1275 { 1276 struct damon_ctx *ctx = kdamond->damon_ctx; 1277 1278 if (!ctx) 1279 return -EINVAL; 1280 damon_sysfs_schemes_update_stats( 1281 kdamond->contexts->contexts_arr[0]->schemes, ctx); 1282 return 0; 1283 } 1284 1285 static int damon_sysfs_upd_schemes_regions_start( 1286 struct damon_sysfs_kdamond *kdamond, bool total_bytes_only) 1287 { 1288 struct damon_ctx *ctx = kdamond->damon_ctx; 1289 1290 if (!ctx) 1291 return -EINVAL; 1292 return damon_sysfs_schemes_update_regions_start( 1293 kdamond->contexts->contexts_arr[0]->schemes, ctx, 1294 total_bytes_only); 1295 } 1296 1297 static int damon_sysfs_upd_schemes_regions_stop( 1298 struct damon_sysfs_kdamond *kdamond) 1299 { 1300 struct damon_ctx *ctx = kdamond->damon_ctx; 1301 1302 if (!ctx) 1303 return -EINVAL; 1304 return damon_sysfs_schemes_update_regions_stop(ctx); 1305 } 1306 1307 static int damon_sysfs_clear_schemes_regions( 1308 struct damon_sysfs_kdamond *kdamond) 1309 { 1310 struct damon_ctx *ctx = kdamond->damon_ctx; 1311 1312 if (!ctx) 1313 return -EINVAL; 1314 return damon_sysfs_schemes_clear_regions( 1315 kdamond->contexts->contexts_arr[0]->schemes, ctx); 1316 } 1317 1318 static inline bool damon_sysfs_kdamond_running( 1319 struct damon_sysfs_kdamond *kdamond) 1320 { 1321 return kdamond->damon_ctx && 1322 damon_sysfs_ctx_running(kdamond->damon_ctx); 1323 } 1324 1325 static int damon_sysfs_apply_inputs(struct damon_ctx *ctx, 1326 struct damon_sysfs_context *sys_ctx) 1327 { 1328 int err; 1329 1330 err = damon_select_ops(ctx, sys_ctx->ops_id); 1331 if (err) 1332 return err; 1333 err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs); 1334 if (err) 1335 return err; 1336 err = damon_sysfs_set_targets(ctx, sys_ctx->targets); 1337 if (err) 1338 return err; 1339 return damon_sysfs_set_schemes(ctx, sys_ctx->schemes); 1340 } 1341 1342 /* 1343 * damon_sysfs_commit_input() - Commit user inputs to a running kdamond. 1344 * @kdamond: The kobject wrapper for the associated kdamond. 1345 * 1346 * If the sysfs input is wrong, the kdamond will be terminated. 1347 */ 1348 static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond) 1349 { 1350 if (!damon_sysfs_kdamond_running(kdamond)) 1351 return -EINVAL; 1352 /* TODO: Support multiple contexts per kdamond */ 1353 if (kdamond->contexts->nr != 1) 1354 return -EINVAL; 1355 1356 return damon_sysfs_apply_inputs(kdamond->damon_ctx, 1357 kdamond->contexts->contexts_arr[0]); 1358 } 1359 1360 static int damon_sysfs_commit_schemes_quota_goals( 1361 struct damon_sysfs_kdamond *sysfs_kdamond) 1362 { 1363 struct damon_ctx *ctx; 1364 struct damon_sysfs_context *sysfs_ctx; 1365 1366 if (!damon_sysfs_kdamond_running(sysfs_kdamond)) 1367 return -EINVAL; 1368 /* TODO: Support multiple contexts per kdamond */ 1369 if (sysfs_kdamond->contexts->nr != 1) 1370 return -EINVAL; 1371 1372 ctx = sysfs_kdamond->damon_ctx; 1373 sysfs_ctx = sysfs_kdamond->contexts->contexts_arr[0]; 1374 damos_sysfs_set_quota_scores(sysfs_ctx->schemes, ctx); 1375 return 0; 1376 } 1377 1378 /* 1379 * damon_sysfs_cmd_request_callback() - DAMON callback for handling requests. 1380 * @c: The DAMON context of the callback. 1381 * @active: Whether @c is not deactivated due to watermarks. 1382 * 1383 * This function is periodically called back from the kdamond thread for @c. 1384 * Then, it checks if there is a waiting DAMON sysfs request and handles it. 1385 */ 1386 static int damon_sysfs_cmd_request_callback(struct damon_ctx *c, bool active) 1387 { 1388 struct damon_sysfs_kdamond *kdamond; 1389 bool total_bytes_only = false; 1390 int err = 0; 1391 1392 /* avoid deadlock due to concurrent state_store('off') */ 1393 if (!damon_sysfs_schemes_regions_updating && 1394 !mutex_trylock(&damon_sysfs_lock)) 1395 return 0; 1396 kdamond = damon_sysfs_cmd_request.kdamond; 1397 if (!kdamond || kdamond->damon_ctx != c) 1398 goto out; 1399 switch (damon_sysfs_cmd_request.cmd) { 1400 case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: 1401 err = damon_sysfs_upd_schemes_stats(kdamond); 1402 break; 1403 case DAMON_SYSFS_CMD_COMMIT: 1404 err = damon_sysfs_commit_input(kdamond); 1405 break; 1406 case DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS: 1407 err = damon_sysfs_commit_schemes_quota_goals(kdamond); 1408 break; 1409 case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: 1410 total_bytes_only = true; 1411 fallthrough; 1412 case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: 1413 if (!damon_sysfs_schemes_regions_updating) { 1414 err = damon_sysfs_upd_schemes_regions_start(kdamond, 1415 total_bytes_only); 1416 if (!err) { 1417 damon_sysfs_schemes_regions_updating = true; 1418 goto keep_lock_out; 1419 } 1420 } else { 1421 /* 1422 * Continue regions updating if DAMON is till 1423 * active and the update for all schemes is not 1424 * finished. 1425 */ 1426 if (active && !damos_sysfs_regions_upd_done()) 1427 goto keep_lock_out; 1428 err = damon_sysfs_upd_schemes_regions_stop(kdamond); 1429 damon_sysfs_schemes_regions_updating = false; 1430 } 1431 break; 1432 case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: 1433 err = damon_sysfs_clear_schemes_regions(kdamond); 1434 break; 1435 default: 1436 break; 1437 } 1438 /* Mark the request as invalid now. */ 1439 damon_sysfs_cmd_request.kdamond = NULL; 1440 out: 1441 if (!damon_sysfs_schemes_regions_updating) 1442 mutex_unlock(&damon_sysfs_lock); 1443 keep_lock_out: 1444 return err; 1445 } 1446 1447 static int damon_sysfs_after_wmarks_check(struct damon_ctx *c) 1448 { 1449 /* 1450 * after_wmarks_check() is called back while the context is deactivated 1451 * by watermarks. 1452 */ 1453 return damon_sysfs_cmd_request_callback(c, false); 1454 } 1455 1456 static int damon_sysfs_after_aggregation(struct damon_ctx *c) 1457 { 1458 /* 1459 * after_aggregation() is called back only while the context is not 1460 * deactivated by watermarks. 1461 */ 1462 return damon_sysfs_cmd_request_callback(c, true); 1463 } 1464 1465 static struct damon_ctx *damon_sysfs_build_ctx( 1466 struct damon_sysfs_context *sys_ctx) 1467 { 1468 struct damon_ctx *ctx = damon_new_ctx(); 1469 int err; 1470 1471 if (!ctx) 1472 return ERR_PTR(-ENOMEM); 1473 1474 err = damon_sysfs_apply_inputs(ctx, sys_ctx); 1475 if (err) { 1476 damon_destroy_ctx(ctx); 1477 return ERR_PTR(err); 1478 } 1479 1480 ctx->callback.after_wmarks_check = damon_sysfs_after_wmarks_check; 1481 ctx->callback.after_aggregation = damon_sysfs_after_aggregation; 1482 ctx->callback.before_terminate = damon_sysfs_before_terminate; 1483 return ctx; 1484 } 1485 1486 static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond) 1487 { 1488 struct damon_ctx *ctx; 1489 int err; 1490 1491 if (damon_sysfs_kdamond_running(kdamond)) 1492 return -EBUSY; 1493 if (damon_sysfs_cmd_request.kdamond == kdamond) 1494 return -EBUSY; 1495 /* TODO: support multiple contexts per kdamond */ 1496 if (kdamond->contexts->nr != 1) 1497 return -EINVAL; 1498 1499 if (kdamond->damon_ctx) 1500 damon_destroy_ctx(kdamond->damon_ctx); 1501 kdamond->damon_ctx = NULL; 1502 1503 ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]); 1504 if (IS_ERR(ctx)) 1505 return PTR_ERR(ctx); 1506 err = damon_start(&ctx, 1, false); 1507 if (err) { 1508 damon_destroy_ctx(ctx); 1509 return err; 1510 } 1511 kdamond->damon_ctx = ctx; 1512 return err; 1513 } 1514 1515 static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond) 1516 { 1517 if (!kdamond->damon_ctx) 1518 return -EINVAL; 1519 return damon_stop(&kdamond->damon_ctx, 1); 1520 /* 1521 * To allow users show final monitoring results of already turned-off 1522 * DAMON, we free kdamond->damon_ctx in next 1523 * damon_sysfs_turn_damon_on(), or kdamonds_nr_store() 1524 */ 1525 } 1526 1527 /* 1528 * damon_sysfs_handle_cmd() - Handle a command for a specific kdamond. 1529 * @cmd: The command to handle. 1530 * @kdamond: The kobject wrapper for the associated kdamond. 1531 * 1532 * This function handles a DAMON sysfs command for a kdamond. For commands 1533 * that need to access running DAMON context-internal data, it requests 1534 * handling of the command to the DAMON callback 1535 * (@damon_sysfs_cmd_request_callback()) and wait until it is properly handled, 1536 * or the context is completed. 1537 * 1538 * Return: 0 on success, negative error code otherwise. 1539 */ 1540 static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd, 1541 struct damon_sysfs_kdamond *kdamond) 1542 { 1543 bool need_wait = true; 1544 1545 /* Handle commands that doesn't access DAMON context-internal data */ 1546 switch (cmd) { 1547 case DAMON_SYSFS_CMD_ON: 1548 return damon_sysfs_turn_damon_on(kdamond); 1549 case DAMON_SYSFS_CMD_OFF: 1550 return damon_sysfs_turn_damon_off(kdamond); 1551 default: 1552 break; 1553 } 1554 1555 /* Pass the command to DAMON callback for safe DAMON context access */ 1556 if (damon_sysfs_cmd_request.kdamond) 1557 return -EBUSY; 1558 if (!damon_sysfs_kdamond_running(kdamond)) 1559 return -EINVAL; 1560 damon_sysfs_cmd_request.cmd = cmd; 1561 damon_sysfs_cmd_request.kdamond = kdamond; 1562 1563 /* 1564 * wait until damon_sysfs_cmd_request_callback() handles the request 1565 * from kdamond context 1566 */ 1567 mutex_unlock(&damon_sysfs_lock); 1568 while (need_wait) { 1569 schedule_timeout_idle(msecs_to_jiffies(100)); 1570 if (!mutex_trylock(&damon_sysfs_lock)) 1571 continue; 1572 if (!damon_sysfs_cmd_request.kdamond) { 1573 /* damon_sysfs_cmd_request_callback() handled */ 1574 need_wait = false; 1575 } else if (!damon_sysfs_kdamond_running(kdamond)) { 1576 /* kdamond has already finished */ 1577 need_wait = false; 1578 damon_sysfs_cmd_request.kdamond = NULL; 1579 } 1580 mutex_unlock(&damon_sysfs_lock); 1581 } 1582 mutex_lock(&damon_sysfs_lock); 1583 return 0; 1584 } 1585 1586 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, 1587 const char *buf, size_t count) 1588 { 1589 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1590 struct damon_sysfs_kdamond, kobj); 1591 enum damon_sysfs_cmd cmd; 1592 ssize_t ret = -EINVAL; 1593 1594 if (!mutex_trylock(&damon_sysfs_lock)) 1595 return -EBUSY; 1596 for (cmd = 0; cmd < NR_DAMON_SYSFS_CMDS; cmd++) { 1597 if (sysfs_streq(buf, damon_sysfs_cmd_strs[cmd])) { 1598 ret = damon_sysfs_handle_cmd(cmd, kdamond); 1599 break; 1600 } 1601 } 1602 mutex_unlock(&damon_sysfs_lock); 1603 if (!ret) 1604 ret = count; 1605 return ret; 1606 } 1607 1608 static ssize_t pid_show(struct kobject *kobj, 1609 struct kobj_attribute *attr, char *buf) 1610 { 1611 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1612 struct damon_sysfs_kdamond, kobj); 1613 struct damon_ctx *ctx; 1614 int pid = -1; 1615 1616 if (!mutex_trylock(&damon_sysfs_lock)) 1617 return -EBUSY; 1618 ctx = kdamond->damon_ctx; 1619 if (!ctx) 1620 goto out; 1621 1622 mutex_lock(&ctx->kdamond_lock); 1623 if (ctx->kdamond) 1624 pid = ctx->kdamond->pid; 1625 mutex_unlock(&ctx->kdamond_lock); 1626 out: 1627 mutex_unlock(&damon_sysfs_lock); 1628 return sysfs_emit(buf, "%d\n", pid); 1629 } 1630 1631 static void damon_sysfs_kdamond_release(struct kobject *kobj) 1632 { 1633 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1634 struct damon_sysfs_kdamond, kobj); 1635 1636 if (kdamond->damon_ctx) 1637 damon_destroy_ctx(kdamond->damon_ctx); 1638 kfree(kdamond); 1639 } 1640 1641 static struct kobj_attribute damon_sysfs_kdamond_state_attr = 1642 __ATTR_RW_MODE(state, 0600); 1643 1644 static struct kobj_attribute damon_sysfs_kdamond_pid_attr = 1645 __ATTR_RO_MODE(pid, 0400); 1646 1647 static struct attribute *damon_sysfs_kdamond_attrs[] = { 1648 &damon_sysfs_kdamond_state_attr.attr, 1649 &damon_sysfs_kdamond_pid_attr.attr, 1650 NULL, 1651 }; 1652 ATTRIBUTE_GROUPS(damon_sysfs_kdamond); 1653 1654 static const struct kobj_type damon_sysfs_kdamond_ktype = { 1655 .release = damon_sysfs_kdamond_release, 1656 .sysfs_ops = &kobj_sysfs_ops, 1657 .default_groups = damon_sysfs_kdamond_groups, 1658 }; 1659 1660 /* 1661 * kdamonds directory 1662 */ 1663 1664 struct damon_sysfs_kdamonds { 1665 struct kobject kobj; 1666 struct damon_sysfs_kdamond **kdamonds_arr; 1667 int nr; 1668 }; 1669 1670 static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void) 1671 { 1672 return kzalloc(sizeof(struct damon_sysfs_kdamonds), GFP_KERNEL); 1673 } 1674 1675 static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds) 1676 { 1677 struct damon_sysfs_kdamond **kdamonds_arr = kdamonds->kdamonds_arr; 1678 int i; 1679 1680 for (i = 0; i < kdamonds->nr; i++) { 1681 damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]); 1682 kobject_put(&kdamonds_arr[i]->kobj); 1683 } 1684 kdamonds->nr = 0; 1685 kfree(kdamonds_arr); 1686 kdamonds->kdamonds_arr = NULL; 1687 } 1688 1689 static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds, 1690 int nr_kdamonds) 1691 { 1692 int i; 1693 1694 for (i = 0; i < nr_kdamonds; i++) { 1695 if (damon_sysfs_kdamond_running(kdamonds[i]) || 1696 damon_sysfs_cmd_request.kdamond == kdamonds[i]) 1697 return true; 1698 } 1699 1700 return false; 1701 } 1702 1703 static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds, 1704 int nr_kdamonds) 1705 { 1706 struct damon_sysfs_kdamond **kdamonds_arr, *kdamond; 1707 int err, i; 1708 1709 if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr)) 1710 return -EBUSY; 1711 1712 damon_sysfs_kdamonds_rm_dirs(kdamonds); 1713 if (!nr_kdamonds) 1714 return 0; 1715 1716 kdamonds_arr = kmalloc_array(nr_kdamonds, sizeof(*kdamonds_arr), 1717 GFP_KERNEL | __GFP_NOWARN); 1718 if (!kdamonds_arr) 1719 return -ENOMEM; 1720 kdamonds->kdamonds_arr = kdamonds_arr; 1721 1722 for (i = 0; i < nr_kdamonds; i++) { 1723 kdamond = damon_sysfs_kdamond_alloc(); 1724 if (!kdamond) { 1725 damon_sysfs_kdamonds_rm_dirs(kdamonds); 1726 return -ENOMEM; 1727 } 1728 1729 err = kobject_init_and_add(&kdamond->kobj, 1730 &damon_sysfs_kdamond_ktype, &kdamonds->kobj, 1731 "%d", i); 1732 if (err) 1733 goto out; 1734 1735 err = damon_sysfs_kdamond_add_dirs(kdamond); 1736 if (err) 1737 goto out; 1738 1739 kdamonds_arr[i] = kdamond; 1740 kdamonds->nr++; 1741 } 1742 return 0; 1743 1744 out: 1745 damon_sysfs_kdamonds_rm_dirs(kdamonds); 1746 kobject_put(&kdamond->kobj); 1747 return err; 1748 } 1749 1750 static ssize_t nr_kdamonds_show(struct kobject *kobj, 1751 struct kobj_attribute *attr, char *buf) 1752 { 1753 struct damon_sysfs_kdamonds *kdamonds = container_of(kobj, 1754 struct damon_sysfs_kdamonds, kobj); 1755 1756 return sysfs_emit(buf, "%d\n", kdamonds->nr); 1757 } 1758 1759 static ssize_t nr_kdamonds_store(struct kobject *kobj, 1760 struct kobj_attribute *attr, const char *buf, size_t count) 1761 { 1762 struct damon_sysfs_kdamonds *kdamonds; 1763 int nr, err; 1764 1765 err = kstrtoint(buf, 0, &nr); 1766 if (err) 1767 return err; 1768 if (nr < 0) 1769 return -EINVAL; 1770 1771 kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj); 1772 1773 if (!mutex_trylock(&damon_sysfs_lock)) 1774 return -EBUSY; 1775 err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr); 1776 mutex_unlock(&damon_sysfs_lock); 1777 if (err) 1778 return err; 1779 1780 return count; 1781 } 1782 1783 static void damon_sysfs_kdamonds_release(struct kobject *kobj) 1784 { 1785 kfree(container_of(kobj, struct damon_sysfs_kdamonds, kobj)); 1786 } 1787 1788 static struct kobj_attribute damon_sysfs_kdamonds_nr_attr = 1789 __ATTR_RW_MODE(nr_kdamonds, 0600); 1790 1791 static struct attribute *damon_sysfs_kdamonds_attrs[] = { 1792 &damon_sysfs_kdamonds_nr_attr.attr, 1793 NULL, 1794 }; 1795 ATTRIBUTE_GROUPS(damon_sysfs_kdamonds); 1796 1797 static const struct kobj_type damon_sysfs_kdamonds_ktype = { 1798 .release = damon_sysfs_kdamonds_release, 1799 .sysfs_ops = &kobj_sysfs_ops, 1800 .default_groups = damon_sysfs_kdamonds_groups, 1801 }; 1802 1803 /* 1804 * damon user interface directory 1805 */ 1806 1807 struct damon_sysfs_ui_dir { 1808 struct kobject kobj; 1809 struct damon_sysfs_kdamonds *kdamonds; 1810 }; 1811 1812 static struct damon_sysfs_ui_dir *damon_sysfs_ui_dir_alloc(void) 1813 { 1814 return kzalloc(sizeof(struct damon_sysfs_ui_dir), GFP_KERNEL); 1815 } 1816 1817 static int damon_sysfs_ui_dir_add_dirs(struct damon_sysfs_ui_dir *ui_dir) 1818 { 1819 struct damon_sysfs_kdamonds *kdamonds; 1820 int err; 1821 1822 kdamonds = damon_sysfs_kdamonds_alloc(); 1823 if (!kdamonds) 1824 return -ENOMEM; 1825 1826 err = kobject_init_and_add(&kdamonds->kobj, 1827 &damon_sysfs_kdamonds_ktype, &ui_dir->kobj, 1828 "kdamonds"); 1829 if (err) { 1830 kobject_put(&kdamonds->kobj); 1831 return err; 1832 } 1833 ui_dir->kdamonds = kdamonds; 1834 return err; 1835 } 1836 1837 static void damon_sysfs_ui_dir_release(struct kobject *kobj) 1838 { 1839 kfree(container_of(kobj, struct damon_sysfs_ui_dir, kobj)); 1840 } 1841 1842 static struct attribute *damon_sysfs_ui_dir_attrs[] = { 1843 NULL, 1844 }; 1845 ATTRIBUTE_GROUPS(damon_sysfs_ui_dir); 1846 1847 static const struct kobj_type damon_sysfs_ui_dir_ktype = { 1848 .release = damon_sysfs_ui_dir_release, 1849 .sysfs_ops = &kobj_sysfs_ops, 1850 .default_groups = damon_sysfs_ui_dir_groups, 1851 }; 1852 1853 static int __init damon_sysfs_init(void) 1854 { 1855 struct kobject *damon_sysfs_root; 1856 struct damon_sysfs_ui_dir *admin; 1857 int err; 1858 1859 damon_sysfs_root = kobject_create_and_add("damon", mm_kobj); 1860 if (!damon_sysfs_root) 1861 return -ENOMEM; 1862 1863 admin = damon_sysfs_ui_dir_alloc(); 1864 if (!admin) { 1865 kobject_put(damon_sysfs_root); 1866 return -ENOMEM; 1867 } 1868 err = kobject_init_and_add(&admin->kobj, &damon_sysfs_ui_dir_ktype, 1869 damon_sysfs_root, "admin"); 1870 if (err) 1871 goto out; 1872 err = damon_sysfs_ui_dir_add_dirs(admin); 1873 if (err) 1874 goto out; 1875 return 0; 1876 1877 out: 1878 kobject_put(&admin->kobj); 1879 kobject_put(damon_sysfs_root); 1880 return err; 1881 } 1882 subsys_initcall(damon_sysfs_init); 1883 1884 #include "sysfs-test.h" 1885