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_UPDATE_SCHEMES_STATS: Update scheme stats sysfs 999 * files. 1000 */ 1001 DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS, 1002 /* 1003 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: Update 1004 * tried_regions/total_bytes sysfs files for each scheme. 1005 */ 1006 DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES, 1007 /* 1008 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried 1009 * regions 1010 */ 1011 DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS, 1012 /* 1013 * @DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: Clear schemes tried 1014 * regions 1015 */ 1016 DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS, 1017 /* 1018 * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands. 1019 */ 1020 NR_DAMON_SYSFS_CMDS, 1021 }; 1022 1023 /* Should match with enum damon_sysfs_cmd */ 1024 static const char * const damon_sysfs_cmd_strs[] = { 1025 "on", 1026 "off", 1027 "commit", 1028 "update_schemes_stats", 1029 "update_schemes_tried_bytes", 1030 "update_schemes_tried_regions", 1031 "clear_schemes_tried_regions", 1032 }; 1033 1034 /* 1035 * struct damon_sysfs_cmd_request - A request to the DAMON callback. 1036 * @cmd: The command that needs to be handled by the callback. 1037 * @kdamond: The kobject wrapper that associated to the kdamond thread. 1038 * 1039 * This structure represents a sysfs command request that need to access some 1040 * DAMON context-internal data. Because DAMON context-internal data can be 1041 * safely accessed from DAMON callbacks without additional synchronization, the 1042 * request will be handled by the DAMON callback. None-``NULL`` @kdamond means 1043 * the request is valid. 1044 */ 1045 struct damon_sysfs_cmd_request { 1046 enum damon_sysfs_cmd cmd; 1047 struct damon_sysfs_kdamond *kdamond; 1048 }; 1049 1050 /* Current DAMON callback request. Protected by damon_sysfs_lock. */ 1051 static struct damon_sysfs_cmd_request damon_sysfs_cmd_request; 1052 1053 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, 1054 char *buf) 1055 { 1056 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1057 struct damon_sysfs_kdamond, kobj); 1058 struct damon_ctx *ctx = kdamond->damon_ctx; 1059 bool running; 1060 1061 if (!ctx) 1062 running = false; 1063 else 1064 running = damon_sysfs_ctx_running(ctx); 1065 1066 return sysfs_emit(buf, "%s\n", running ? 1067 damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] : 1068 damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_OFF]); 1069 } 1070 1071 static int damon_sysfs_set_attrs(struct damon_ctx *ctx, 1072 struct damon_sysfs_attrs *sys_attrs) 1073 { 1074 struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals; 1075 struct damon_sysfs_ul_range *sys_nr_regions = 1076 sys_attrs->nr_regions_range; 1077 struct damon_attrs attrs = { 1078 .sample_interval = sys_intervals->sample_us, 1079 .aggr_interval = sys_intervals->aggr_us, 1080 .ops_update_interval = sys_intervals->update_us, 1081 .min_nr_regions = sys_nr_regions->min, 1082 .max_nr_regions = sys_nr_regions->max, 1083 }; 1084 return damon_set_attrs(ctx, &attrs); 1085 } 1086 1087 static void damon_sysfs_destroy_targets(struct damon_ctx *ctx) 1088 { 1089 struct damon_target *t, *next; 1090 bool has_pid = damon_target_has_pid(ctx); 1091 1092 damon_for_each_target_safe(t, next, ctx) { 1093 if (has_pid) 1094 put_pid(t->pid); 1095 damon_destroy_target(t); 1096 } 1097 } 1098 1099 static int damon_sysfs_set_regions(struct damon_target *t, 1100 struct damon_sysfs_regions *sysfs_regions) 1101 { 1102 struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr, 1103 sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN); 1104 int i, err = -EINVAL; 1105 1106 if (!ranges) 1107 return -ENOMEM; 1108 for (i = 0; i < sysfs_regions->nr; i++) { 1109 struct damon_sysfs_region *sys_region = 1110 sysfs_regions->regions_arr[i]; 1111 1112 if (sys_region->ar.start > sys_region->ar.end) 1113 goto out; 1114 1115 ranges[i].start = sys_region->ar.start; 1116 ranges[i].end = sys_region->ar.end; 1117 if (i == 0) 1118 continue; 1119 if (ranges[i - 1].end > ranges[i].start) 1120 goto out; 1121 } 1122 err = damon_set_regions(t, ranges, sysfs_regions->nr); 1123 out: 1124 kfree(ranges); 1125 return err; 1126 1127 } 1128 1129 static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target, 1130 struct damon_ctx *ctx) 1131 { 1132 struct damon_target *t = damon_new_target(); 1133 int err = -EINVAL; 1134 1135 if (!t) 1136 return -ENOMEM; 1137 damon_add_target(ctx, t); 1138 if (damon_target_has_pid(ctx)) { 1139 t->pid = find_get_pid(sys_target->pid); 1140 if (!t->pid) 1141 goto destroy_targets_out; 1142 } 1143 err = damon_sysfs_set_regions(t, sys_target->regions); 1144 if (err) 1145 goto destroy_targets_out; 1146 return 0; 1147 1148 destroy_targets_out: 1149 damon_sysfs_destroy_targets(ctx); 1150 return err; 1151 } 1152 1153 static int damon_sysfs_update_target_pid(struct damon_target *target, int pid) 1154 { 1155 struct pid *pid_new; 1156 1157 pid_new = find_get_pid(pid); 1158 if (!pid_new) 1159 return -EINVAL; 1160 1161 if (pid_new == target->pid) { 1162 put_pid(pid_new); 1163 return 0; 1164 } 1165 1166 put_pid(target->pid); 1167 target->pid = pid_new; 1168 return 0; 1169 } 1170 1171 static int damon_sysfs_update_target(struct damon_target *target, 1172 struct damon_ctx *ctx, 1173 struct damon_sysfs_target *sys_target) 1174 { 1175 int err; 1176 1177 if (damon_target_has_pid(ctx)) { 1178 err = damon_sysfs_update_target_pid(target, sys_target->pid); 1179 if (err) 1180 return err; 1181 } 1182 1183 /* 1184 * Do monitoring target region boundary update only if one or more 1185 * regions are set by the user. This is for keeping current monitoring 1186 * target results and range easier, especially for dynamic monitoring 1187 * target regions update ops like 'vaddr'. 1188 */ 1189 if (sys_target->regions->nr) 1190 err = damon_sysfs_set_regions(target, sys_target->regions); 1191 return err; 1192 } 1193 1194 static int damon_sysfs_set_targets(struct damon_ctx *ctx, 1195 struct damon_sysfs_targets *sysfs_targets) 1196 { 1197 struct damon_target *t, *next; 1198 int i = 0, err; 1199 1200 /* Multiple physical address space monitoring targets makes no sense */ 1201 if (ctx->ops.id == DAMON_OPS_PADDR && sysfs_targets->nr > 1) 1202 return -EINVAL; 1203 1204 damon_for_each_target_safe(t, next, ctx) { 1205 if (i < sysfs_targets->nr) { 1206 damon_sysfs_update_target(t, ctx, 1207 sysfs_targets->targets_arr[i]); 1208 } else { 1209 if (damon_target_has_pid(ctx)) 1210 put_pid(t->pid); 1211 damon_destroy_target(t); 1212 } 1213 i++; 1214 } 1215 1216 for (; i < sysfs_targets->nr; i++) { 1217 struct damon_sysfs_target *st = sysfs_targets->targets_arr[i]; 1218 1219 err = damon_sysfs_add_target(st, ctx); 1220 if (err) 1221 return err; 1222 } 1223 return 0; 1224 } 1225 1226 static bool damon_sysfs_schemes_regions_updating; 1227 1228 static void damon_sysfs_before_terminate(struct damon_ctx *ctx) 1229 { 1230 struct damon_target *t, *next; 1231 struct damon_sysfs_kdamond *kdamond; 1232 enum damon_sysfs_cmd cmd; 1233 1234 /* damon_sysfs_schemes_update_regions_stop() might not yet called */ 1235 kdamond = damon_sysfs_cmd_request.kdamond; 1236 cmd = damon_sysfs_cmd_request.cmd; 1237 if (kdamond && ctx == kdamond->damon_ctx && 1238 (cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS || 1239 cmd == DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES) && 1240 damon_sysfs_schemes_regions_updating) { 1241 damon_sysfs_schemes_update_regions_stop(ctx); 1242 damon_sysfs_schemes_regions_updating = false; 1243 mutex_unlock(&damon_sysfs_lock); 1244 } 1245 1246 if (!damon_target_has_pid(ctx)) 1247 return; 1248 1249 mutex_lock(&ctx->kdamond_lock); 1250 damon_for_each_target_safe(t, next, ctx) { 1251 put_pid(t->pid); 1252 damon_destroy_target(t); 1253 } 1254 mutex_unlock(&ctx->kdamond_lock); 1255 } 1256 1257 /* 1258 * damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files. 1259 * @kdamond: The kobject wrapper that associated to the kdamond thread. 1260 * 1261 * This function reads the schemes stats of specific kdamond and update the 1262 * related values for sysfs files. This function should be called from DAMON 1263 * callbacks while holding ``damon_syfs_lock``, to safely access the DAMON 1264 * contexts-internal data and DAMON sysfs variables. 1265 */ 1266 static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond) 1267 { 1268 struct damon_ctx *ctx = kdamond->damon_ctx; 1269 1270 if (!ctx) 1271 return -EINVAL; 1272 damon_sysfs_schemes_update_stats( 1273 kdamond->contexts->contexts_arr[0]->schemes, ctx); 1274 return 0; 1275 } 1276 1277 static int damon_sysfs_upd_schemes_regions_start( 1278 struct damon_sysfs_kdamond *kdamond, bool total_bytes_only) 1279 { 1280 struct damon_ctx *ctx = kdamond->damon_ctx; 1281 1282 if (!ctx) 1283 return -EINVAL; 1284 return damon_sysfs_schemes_update_regions_start( 1285 kdamond->contexts->contexts_arr[0]->schemes, ctx, 1286 total_bytes_only); 1287 } 1288 1289 static int damon_sysfs_upd_schemes_regions_stop( 1290 struct damon_sysfs_kdamond *kdamond) 1291 { 1292 struct damon_ctx *ctx = kdamond->damon_ctx; 1293 1294 if (!ctx) 1295 return -EINVAL; 1296 return damon_sysfs_schemes_update_regions_stop(ctx); 1297 } 1298 1299 static int damon_sysfs_clear_schemes_regions( 1300 struct damon_sysfs_kdamond *kdamond) 1301 { 1302 struct damon_ctx *ctx = kdamond->damon_ctx; 1303 1304 if (!ctx) 1305 return -EINVAL; 1306 return damon_sysfs_schemes_clear_regions( 1307 kdamond->contexts->contexts_arr[0]->schemes, ctx); 1308 } 1309 1310 static inline bool damon_sysfs_kdamond_running( 1311 struct damon_sysfs_kdamond *kdamond) 1312 { 1313 return kdamond->damon_ctx && 1314 damon_sysfs_ctx_running(kdamond->damon_ctx); 1315 } 1316 1317 static int damon_sysfs_apply_inputs(struct damon_ctx *ctx, 1318 struct damon_sysfs_context *sys_ctx) 1319 { 1320 int err; 1321 1322 err = damon_select_ops(ctx, sys_ctx->ops_id); 1323 if (err) 1324 return err; 1325 err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs); 1326 if (err) 1327 return err; 1328 err = damon_sysfs_set_targets(ctx, sys_ctx->targets); 1329 if (err) 1330 return err; 1331 return damon_sysfs_set_schemes(ctx, sys_ctx->schemes); 1332 } 1333 1334 /* 1335 * damon_sysfs_commit_input() - Commit user inputs to a running kdamond. 1336 * @kdamond: The kobject wrapper for the associated kdamond. 1337 * 1338 * If the sysfs input is wrong, the kdamond will be terminated. 1339 */ 1340 static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond) 1341 { 1342 if (!damon_sysfs_kdamond_running(kdamond)) 1343 return -EINVAL; 1344 /* TODO: Support multiple contexts per kdamond */ 1345 if (kdamond->contexts->nr != 1) 1346 return -EINVAL; 1347 1348 return damon_sysfs_apply_inputs(kdamond->damon_ctx, 1349 kdamond->contexts->contexts_arr[0]); 1350 } 1351 1352 /* 1353 * damon_sysfs_cmd_request_callback() - DAMON callback for handling requests. 1354 * @c: The DAMON context of the callback. 1355 * @active: Whether @c is not deactivated due to watermarks. 1356 * 1357 * This function is periodically called back from the kdamond thread for @c. 1358 * Then, it checks if there is a waiting DAMON sysfs request and handles it. 1359 */ 1360 static int damon_sysfs_cmd_request_callback(struct damon_ctx *c, bool active) 1361 { 1362 struct damon_sysfs_kdamond *kdamond; 1363 bool total_bytes_only = false; 1364 int err = 0; 1365 1366 /* avoid deadlock due to concurrent state_store('off') */ 1367 if (!damon_sysfs_schemes_regions_updating && 1368 !mutex_trylock(&damon_sysfs_lock)) 1369 return 0; 1370 kdamond = damon_sysfs_cmd_request.kdamond; 1371 if (!kdamond || kdamond->damon_ctx != c) 1372 goto out; 1373 switch (damon_sysfs_cmd_request.cmd) { 1374 case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: 1375 err = damon_sysfs_upd_schemes_stats(kdamond); 1376 break; 1377 case DAMON_SYSFS_CMD_COMMIT: 1378 err = damon_sysfs_commit_input(kdamond); 1379 break; 1380 case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: 1381 total_bytes_only = true; 1382 fallthrough; 1383 case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: 1384 if (!damon_sysfs_schemes_regions_updating) { 1385 err = damon_sysfs_upd_schemes_regions_start(kdamond, 1386 total_bytes_only); 1387 if (!err) { 1388 damon_sysfs_schemes_regions_updating = true; 1389 goto keep_lock_out; 1390 } 1391 } else { 1392 /* 1393 * Continue regions updating if DAMON is till 1394 * active and the update for all schemes is not 1395 * finished. 1396 */ 1397 if (active && !damos_sysfs_regions_upd_done()) 1398 goto keep_lock_out; 1399 err = damon_sysfs_upd_schemes_regions_stop(kdamond); 1400 damon_sysfs_schemes_regions_updating = false; 1401 } 1402 break; 1403 case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: 1404 err = damon_sysfs_clear_schemes_regions(kdamond); 1405 break; 1406 default: 1407 break; 1408 } 1409 /* Mark the request as invalid now. */ 1410 damon_sysfs_cmd_request.kdamond = NULL; 1411 out: 1412 if (!damon_sysfs_schemes_regions_updating) 1413 mutex_unlock(&damon_sysfs_lock); 1414 keep_lock_out: 1415 return err; 1416 } 1417 1418 static int damon_sysfs_after_wmarks_check(struct damon_ctx *c) 1419 { 1420 /* 1421 * after_wmarks_check() is called back while the context is deactivated 1422 * by watermarks. 1423 */ 1424 return damon_sysfs_cmd_request_callback(c, false); 1425 } 1426 1427 static int damon_sysfs_after_aggregation(struct damon_ctx *c) 1428 { 1429 /* 1430 * after_aggregation() is called back only while the context is not 1431 * deactivated by watermarks. 1432 */ 1433 return damon_sysfs_cmd_request_callback(c, true); 1434 } 1435 1436 static struct damon_ctx *damon_sysfs_build_ctx( 1437 struct damon_sysfs_context *sys_ctx) 1438 { 1439 struct damon_ctx *ctx = damon_new_ctx(); 1440 int err; 1441 1442 if (!ctx) 1443 return ERR_PTR(-ENOMEM); 1444 1445 err = damon_sysfs_apply_inputs(ctx, sys_ctx); 1446 if (err) { 1447 damon_destroy_ctx(ctx); 1448 return ERR_PTR(err); 1449 } 1450 1451 ctx->callback.after_wmarks_check = damon_sysfs_after_wmarks_check; 1452 ctx->callback.after_aggregation = damon_sysfs_after_aggregation; 1453 ctx->callback.before_terminate = damon_sysfs_before_terminate; 1454 return ctx; 1455 } 1456 1457 static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond) 1458 { 1459 struct damon_ctx *ctx; 1460 int err; 1461 1462 if (damon_sysfs_kdamond_running(kdamond)) 1463 return -EBUSY; 1464 if (damon_sysfs_cmd_request.kdamond == kdamond) 1465 return -EBUSY; 1466 /* TODO: support multiple contexts per kdamond */ 1467 if (kdamond->contexts->nr != 1) 1468 return -EINVAL; 1469 1470 if (kdamond->damon_ctx) 1471 damon_destroy_ctx(kdamond->damon_ctx); 1472 kdamond->damon_ctx = NULL; 1473 1474 ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]); 1475 if (IS_ERR(ctx)) 1476 return PTR_ERR(ctx); 1477 err = damon_start(&ctx, 1, false); 1478 if (err) { 1479 damon_destroy_ctx(ctx); 1480 return err; 1481 } 1482 kdamond->damon_ctx = ctx; 1483 return err; 1484 } 1485 1486 static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond) 1487 { 1488 if (!kdamond->damon_ctx) 1489 return -EINVAL; 1490 return damon_stop(&kdamond->damon_ctx, 1); 1491 /* 1492 * To allow users show final monitoring results of already turned-off 1493 * DAMON, we free kdamond->damon_ctx in next 1494 * damon_sysfs_turn_damon_on(), or kdamonds_nr_store() 1495 */ 1496 } 1497 1498 /* 1499 * damon_sysfs_handle_cmd() - Handle a command for a specific kdamond. 1500 * @cmd: The command to handle. 1501 * @kdamond: The kobject wrapper for the associated kdamond. 1502 * 1503 * This function handles a DAMON sysfs command for a kdamond. For commands 1504 * that need to access running DAMON context-internal data, it requests 1505 * handling of the command to the DAMON callback 1506 * (@damon_sysfs_cmd_request_callback()) and wait until it is properly handled, 1507 * or the context is completed. 1508 * 1509 * Return: 0 on success, negative error code otherwise. 1510 */ 1511 static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd, 1512 struct damon_sysfs_kdamond *kdamond) 1513 { 1514 bool need_wait = true; 1515 1516 /* Handle commands that doesn't access DAMON context-internal data */ 1517 switch (cmd) { 1518 case DAMON_SYSFS_CMD_ON: 1519 return damon_sysfs_turn_damon_on(kdamond); 1520 case DAMON_SYSFS_CMD_OFF: 1521 return damon_sysfs_turn_damon_off(kdamond); 1522 default: 1523 break; 1524 } 1525 1526 /* Pass the command to DAMON callback for safe DAMON context access */ 1527 if (damon_sysfs_cmd_request.kdamond) 1528 return -EBUSY; 1529 if (!damon_sysfs_kdamond_running(kdamond)) 1530 return -EINVAL; 1531 damon_sysfs_cmd_request.cmd = cmd; 1532 damon_sysfs_cmd_request.kdamond = kdamond; 1533 1534 /* 1535 * wait until damon_sysfs_cmd_request_callback() handles the request 1536 * from kdamond context 1537 */ 1538 mutex_unlock(&damon_sysfs_lock); 1539 while (need_wait) { 1540 schedule_timeout_idle(msecs_to_jiffies(100)); 1541 if (!mutex_trylock(&damon_sysfs_lock)) 1542 continue; 1543 if (!damon_sysfs_cmd_request.kdamond) { 1544 /* damon_sysfs_cmd_request_callback() handled */ 1545 need_wait = false; 1546 } else if (!damon_sysfs_kdamond_running(kdamond)) { 1547 /* kdamond has already finished */ 1548 need_wait = false; 1549 damon_sysfs_cmd_request.kdamond = NULL; 1550 } 1551 mutex_unlock(&damon_sysfs_lock); 1552 } 1553 mutex_lock(&damon_sysfs_lock); 1554 return 0; 1555 } 1556 1557 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, 1558 const char *buf, size_t count) 1559 { 1560 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1561 struct damon_sysfs_kdamond, kobj); 1562 enum damon_sysfs_cmd cmd; 1563 ssize_t ret = -EINVAL; 1564 1565 if (!mutex_trylock(&damon_sysfs_lock)) 1566 return -EBUSY; 1567 for (cmd = 0; cmd < NR_DAMON_SYSFS_CMDS; cmd++) { 1568 if (sysfs_streq(buf, damon_sysfs_cmd_strs[cmd])) { 1569 ret = damon_sysfs_handle_cmd(cmd, kdamond); 1570 break; 1571 } 1572 } 1573 mutex_unlock(&damon_sysfs_lock); 1574 if (!ret) 1575 ret = count; 1576 return ret; 1577 } 1578 1579 static ssize_t pid_show(struct kobject *kobj, 1580 struct kobj_attribute *attr, char *buf) 1581 { 1582 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1583 struct damon_sysfs_kdamond, kobj); 1584 struct damon_ctx *ctx; 1585 int pid = -1; 1586 1587 if (!mutex_trylock(&damon_sysfs_lock)) 1588 return -EBUSY; 1589 ctx = kdamond->damon_ctx; 1590 if (!ctx) 1591 goto out; 1592 1593 mutex_lock(&ctx->kdamond_lock); 1594 if (ctx->kdamond) 1595 pid = ctx->kdamond->pid; 1596 mutex_unlock(&ctx->kdamond_lock); 1597 out: 1598 mutex_unlock(&damon_sysfs_lock); 1599 return sysfs_emit(buf, "%d\n", pid); 1600 } 1601 1602 static void damon_sysfs_kdamond_release(struct kobject *kobj) 1603 { 1604 struct damon_sysfs_kdamond *kdamond = container_of(kobj, 1605 struct damon_sysfs_kdamond, kobj); 1606 1607 if (kdamond->damon_ctx) 1608 damon_destroy_ctx(kdamond->damon_ctx); 1609 kfree(kdamond); 1610 } 1611 1612 static struct kobj_attribute damon_sysfs_kdamond_state_attr = 1613 __ATTR_RW_MODE(state, 0600); 1614 1615 static struct kobj_attribute damon_sysfs_kdamond_pid_attr = 1616 __ATTR_RO_MODE(pid, 0400); 1617 1618 static struct attribute *damon_sysfs_kdamond_attrs[] = { 1619 &damon_sysfs_kdamond_state_attr.attr, 1620 &damon_sysfs_kdamond_pid_attr.attr, 1621 NULL, 1622 }; 1623 ATTRIBUTE_GROUPS(damon_sysfs_kdamond); 1624 1625 static const struct kobj_type damon_sysfs_kdamond_ktype = { 1626 .release = damon_sysfs_kdamond_release, 1627 .sysfs_ops = &kobj_sysfs_ops, 1628 .default_groups = damon_sysfs_kdamond_groups, 1629 }; 1630 1631 /* 1632 * kdamonds directory 1633 */ 1634 1635 struct damon_sysfs_kdamonds { 1636 struct kobject kobj; 1637 struct damon_sysfs_kdamond **kdamonds_arr; 1638 int nr; 1639 }; 1640 1641 static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void) 1642 { 1643 return kzalloc(sizeof(struct damon_sysfs_kdamonds), GFP_KERNEL); 1644 } 1645 1646 static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds) 1647 { 1648 struct damon_sysfs_kdamond **kdamonds_arr = kdamonds->kdamonds_arr; 1649 int i; 1650 1651 for (i = 0; i < kdamonds->nr; i++) { 1652 damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]); 1653 kobject_put(&kdamonds_arr[i]->kobj); 1654 } 1655 kdamonds->nr = 0; 1656 kfree(kdamonds_arr); 1657 kdamonds->kdamonds_arr = NULL; 1658 } 1659 1660 static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds, 1661 int nr_kdamonds) 1662 { 1663 int i; 1664 1665 for (i = 0; i < nr_kdamonds; i++) { 1666 if (damon_sysfs_kdamond_running(kdamonds[i]) || 1667 damon_sysfs_cmd_request.kdamond == kdamonds[i]) 1668 return true; 1669 } 1670 1671 return false; 1672 } 1673 1674 static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds, 1675 int nr_kdamonds) 1676 { 1677 struct damon_sysfs_kdamond **kdamonds_arr, *kdamond; 1678 int err, i; 1679 1680 if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr)) 1681 return -EBUSY; 1682 1683 damon_sysfs_kdamonds_rm_dirs(kdamonds); 1684 if (!nr_kdamonds) 1685 return 0; 1686 1687 kdamonds_arr = kmalloc_array(nr_kdamonds, sizeof(*kdamonds_arr), 1688 GFP_KERNEL | __GFP_NOWARN); 1689 if (!kdamonds_arr) 1690 return -ENOMEM; 1691 kdamonds->kdamonds_arr = kdamonds_arr; 1692 1693 for (i = 0; i < nr_kdamonds; i++) { 1694 kdamond = damon_sysfs_kdamond_alloc(); 1695 if (!kdamond) { 1696 damon_sysfs_kdamonds_rm_dirs(kdamonds); 1697 return -ENOMEM; 1698 } 1699 1700 err = kobject_init_and_add(&kdamond->kobj, 1701 &damon_sysfs_kdamond_ktype, &kdamonds->kobj, 1702 "%d", i); 1703 if (err) 1704 goto out; 1705 1706 err = damon_sysfs_kdamond_add_dirs(kdamond); 1707 if (err) 1708 goto out; 1709 1710 kdamonds_arr[i] = kdamond; 1711 kdamonds->nr++; 1712 } 1713 return 0; 1714 1715 out: 1716 damon_sysfs_kdamonds_rm_dirs(kdamonds); 1717 kobject_put(&kdamond->kobj); 1718 return err; 1719 } 1720 1721 static ssize_t nr_kdamonds_show(struct kobject *kobj, 1722 struct kobj_attribute *attr, char *buf) 1723 { 1724 struct damon_sysfs_kdamonds *kdamonds = container_of(kobj, 1725 struct damon_sysfs_kdamonds, kobj); 1726 1727 return sysfs_emit(buf, "%d\n", kdamonds->nr); 1728 } 1729 1730 static ssize_t nr_kdamonds_store(struct kobject *kobj, 1731 struct kobj_attribute *attr, const char *buf, size_t count) 1732 { 1733 struct damon_sysfs_kdamonds *kdamonds; 1734 int nr, err; 1735 1736 err = kstrtoint(buf, 0, &nr); 1737 if (err) 1738 return err; 1739 if (nr < 0) 1740 return -EINVAL; 1741 1742 kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj); 1743 1744 if (!mutex_trylock(&damon_sysfs_lock)) 1745 return -EBUSY; 1746 err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr); 1747 mutex_unlock(&damon_sysfs_lock); 1748 if (err) 1749 return err; 1750 1751 return count; 1752 } 1753 1754 static void damon_sysfs_kdamonds_release(struct kobject *kobj) 1755 { 1756 kfree(container_of(kobj, struct damon_sysfs_kdamonds, kobj)); 1757 } 1758 1759 static struct kobj_attribute damon_sysfs_kdamonds_nr_attr = 1760 __ATTR_RW_MODE(nr_kdamonds, 0600); 1761 1762 static struct attribute *damon_sysfs_kdamonds_attrs[] = { 1763 &damon_sysfs_kdamonds_nr_attr.attr, 1764 NULL, 1765 }; 1766 ATTRIBUTE_GROUPS(damon_sysfs_kdamonds); 1767 1768 static const struct kobj_type damon_sysfs_kdamonds_ktype = { 1769 .release = damon_sysfs_kdamonds_release, 1770 .sysfs_ops = &kobj_sysfs_ops, 1771 .default_groups = damon_sysfs_kdamonds_groups, 1772 }; 1773 1774 /* 1775 * damon user interface directory 1776 */ 1777 1778 struct damon_sysfs_ui_dir { 1779 struct kobject kobj; 1780 struct damon_sysfs_kdamonds *kdamonds; 1781 }; 1782 1783 static struct damon_sysfs_ui_dir *damon_sysfs_ui_dir_alloc(void) 1784 { 1785 return kzalloc(sizeof(struct damon_sysfs_ui_dir), GFP_KERNEL); 1786 } 1787 1788 static int damon_sysfs_ui_dir_add_dirs(struct damon_sysfs_ui_dir *ui_dir) 1789 { 1790 struct damon_sysfs_kdamonds *kdamonds; 1791 int err; 1792 1793 kdamonds = damon_sysfs_kdamonds_alloc(); 1794 if (!kdamonds) 1795 return -ENOMEM; 1796 1797 err = kobject_init_and_add(&kdamonds->kobj, 1798 &damon_sysfs_kdamonds_ktype, &ui_dir->kobj, 1799 "kdamonds"); 1800 if (err) { 1801 kobject_put(&kdamonds->kobj); 1802 return err; 1803 } 1804 ui_dir->kdamonds = kdamonds; 1805 return err; 1806 } 1807 1808 static void damon_sysfs_ui_dir_release(struct kobject *kobj) 1809 { 1810 kfree(container_of(kobj, struct damon_sysfs_ui_dir, kobj)); 1811 } 1812 1813 static struct attribute *damon_sysfs_ui_dir_attrs[] = { 1814 NULL, 1815 }; 1816 ATTRIBUTE_GROUPS(damon_sysfs_ui_dir); 1817 1818 static const struct kobj_type damon_sysfs_ui_dir_ktype = { 1819 .release = damon_sysfs_ui_dir_release, 1820 .sysfs_ops = &kobj_sysfs_ops, 1821 .default_groups = damon_sysfs_ui_dir_groups, 1822 }; 1823 1824 static int __init damon_sysfs_init(void) 1825 { 1826 struct kobject *damon_sysfs_root; 1827 struct damon_sysfs_ui_dir *admin; 1828 int err; 1829 1830 damon_sysfs_root = kobject_create_and_add("damon", mm_kobj); 1831 if (!damon_sysfs_root) 1832 return -ENOMEM; 1833 1834 admin = damon_sysfs_ui_dir_alloc(); 1835 if (!admin) { 1836 kobject_put(damon_sysfs_root); 1837 return -ENOMEM; 1838 } 1839 err = kobject_init_and_add(&admin->kobj, &damon_sysfs_ui_dir_ktype, 1840 damon_sysfs_root, "admin"); 1841 if (err) 1842 goto out; 1843 err = damon_sysfs_ui_dir_add_dirs(admin); 1844 if (err) 1845 goto out; 1846 return 0; 1847 1848 out: 1849 kobject_put(&admin->kobj); 1850 kobject_put(damon_sysfs_root); 1851 return err; 1852 } 1853 subsys_initcall(damon_sysfs_init); 1854 1855 #include "sysfs-test.h" 1856