12224d848SSeongJae Park // SPDX-License-Identifier: GPL-2.0 22224d848SSeongJae Park /* 32224d848SSeongJae Park * Data Access Monitor 42224d848SSeongJae Park * 52224d848SSeongJae Park * Author: SeongJae Park <sjpark@amazon.de> 62224d848SSeongJae Park */ 72224d848SSeongJae Park 82224d848SSeongJae Park #define pr_fmt(fmt) "damon: " fmt 92224d848SSeongJae Park 102224d848SSeongJae Park #include <linux/damon.h> 112224d848SSeongJae Park #include <linux/delay.h> 122224d848SSeongJae Park #include <linux/kthread.h> 13ee801b7dSSeongJae Park #include <linux/mm.h> 142224d848SSeongJae Park #include <linux/slab.h> 1538683e00SSeongJae Park #include <linux/string.h> 162224d848SSeongJae Park 172fcb9362SSeongJae Park #define CREATE_TRACE_POINTS 182fcb9362SSeongJae Park #include <trace/events/damon.h> 192fcb9362SSeongJae Park 2017ccae8bSSeongJae Park #ifdef CONFIG_DAMON_KUNIT_TEST 2117ccae8bSSeongJae Park #undef DAMON_MIN_REGION 2217ccae8bSSeongJae Park #define DAMON_MIN_REGION 1 2317ccae8bSSeongJae Park #endif 2417ccae8bSSeongJae Park 252224d848SSeongJae Park static DEFINE_MUTEX(damon_lock); 262224d848SSeongJae Park static int nr_running_ctxs; 278b9b0d33SSeongJae Park static bool running_exclusive_ctxs; 282224d848SSeongJae Park 299f7b053aSSeongJae Park static DEFINE_MUTEX(damon_ops_lock); 309f7b053aSSeongJae Park static struct damon_operations damon_registered_ops[NR_DAMON_OPS]; 319f7b053aSSeongJae Park 32a1870944SDawei Li static struct kmem_cache *damon_region_cache __ro_after_init; 33a1870944SDawei Li 349f7b053aSSeongJae Park /* Should be called under damon_ops_lock with id smaller than NR_DAMON_OPS */ 35152e5617SSeongJae Park static bool __damon_is_registered_ops(enum damon_ops_id id) 369f7b053aSSeongJae Park { 379f7b053aSSeongJae Park struct damon_operations empty_ops = {}; 389f7b053aSSeongJae Park 399f7b053aSSeongJae Park if (!memcmp(&empty_ops, &damon_registered_ops[id], sizeof(empty_ops))) 409f7b053aSSeongJae Park return false; 419f7b053aSSeongJae Park return true; 429f7b053aSSeongJae Park } 439f7b053aSSeongJae Park 449f7b053aSSeongJae Park /** 45152e5617SSeongJae Park * damon_is_registered_ops() - Check if a given damon_operations is registered. 46152e5617SSeongJae Park * @id: Id of the damon_operations to check if registered. 47152e5617SSeongJae Park * 48152e5617SSeongJae Park * Return: true if the ops is set, false otherwise. 49152e5617SSeongJae Park */ 50152e5617SSeongJae Park bool damon_is_registered_ops(enum damon_ops_id id) 51152e5617SSeongJae Park { 52152e5617SSeongJae Park bool registered; 53152e5617SSeongJae Park 54152e5617SSeongJae Park if (id >= NR_DAMON_OPS) 55152e5617SSeongJae Park return false; 56152e5617SSeongJae Park mutex_lock(&damon_ops_lock); 57152e5617SSeongJae Park registered = __damon_is_registered_ops(id); 58152e5617SSeongJae Park mutex_unlock(&damon_ops_lock); 59152e5617SSeongJae Park return registered; 60152e5617SSeongJae Park } 61152e5617SSeongJae Park 62152e5617SSeongJae Park /** 639f7b053aSSeongJae Park * damon_register_ops() - Register a monitoring operations set to DAMON. 649f7b053aSSeongJae Park * @ops: monitoring operations set to register. 659f7b053aSSeongJae Park * 669f7b053aSSeongJae Park * This function registers a monitoring operations set of valid &struct 679f7b053aSSeongJae Park * damon_operations->id so that others can find and use them later. 689f7b053aSSeongJae Park * 699f7b053aSSeongJae Park * Return: 0 on success, negative error code otherwise. 709f7b053aSSeongJae Park */ 719f7b053aSSeongJae Park int damon_register_ops(struct damon_operations *ops) 729f7b053aSSeongJae Park { 739f7b053aSSeongJae Park int err = 0; 749f7b053aSSeongJae Park 759f7b053aSSeongJae Park if (ops->id >= NR_DAMON_OPS) 769f7b053aSSeongJae Park return -EINVAL; 779f7b053aSSeongJae Park mutex_lock(&damon_ops_lock); 789f7b053aSSeongJae Park /* Fail for already registered ops */ 79152e5617SSeongJae Park if (__damon_is_registered_ops(ops->id)) { 809f7b053aSSeongJae Park err = -EINVAL; 819f7b053aSSeongJae Park goto out; 829f7b053aSSeongJae Park } 839f7b053aSSeongJae Park damon_registered_ops[ops->id] = *ops; 849f7b053aSSeongJae Park out: 859f7b053aSSeongJae Park mutex_unlock(&damon_ops_lock); 869f7b053aSSeongJae Park return err; 879f7b053aSSeongJae Park } 889f7b053aSSeongJae Park 899f7b053aSSeongJae Park /** 909f7b053aSSeongJae Park * damon_select_ops() - Select a monitoring operations to use with the context. 919f7b053aSSeongJae Park * @ctx: monitoring context to use the operations. 929f7b053aSSeongJae Park * @id: id of the registered monitoring operations to select. 939f7b053aSSeongJae Park * 949f7b053aSSeongJae Park * This function finds registered monitoring operations set of @id and make 959f7b053aSSeongJae Park * @ctx to use it. 969f7b053aSSeongJae Park * 979f7b053aSSeongJae Park * Return: 0 on success, negative error code otherwise. 989f7b053aSSeongJae Park */ 999f7b053aSSeongJae Park int damon_select_ops(struct damon_ctx *ctx, enum damon_ops_id id) 1009f7b053aSSeongJae Park { 1019f7b053aSSeongJae Park int err = 0; 1029f7b053aSSeongJae Park 1039f7b053aSSeongJae Park if (id >= NR_DAMON_OPS) 1049f7b053aSSeongJae Park return -EINVAL; 1059f7b053aSSeongJae Park 1069f7b053aSSeongJae Park mutex_lock(&damon_ops_lock); 107152e5617SSeongJae Park if (!__damon_is_registered_ops(id)) 1089f7b053aSSeongJae Park err = -EINVAL; 1099f7b053aSSeongJae Park else 1109f7b053aSSeongJae Park ctx->ops = damon_registered_ops[id]; 1119f7b053aSSeongJae Park mutex_unlock(&damon_ops_lock); 1129f7b053aSSeongJae Park return err; 1139f7b053aSSeongJae Park } 1149f7b053aSSeongJae Park 115f23b8eeeSSeongJae Park /* 116f23b8eeeSSeongJae Park * Construct a damon_region struct 117f23b8eeeSSeongJae Park * 118f23b8eeeSSeongJae Park * Returns the pointer to the new struct if success, or NULL otherwise 119f23b8eeeSSeongJae Park */ 120f23b8eeeSSeongJae Park struct damon_region *damon_new_region(unsigned long start, unsigned long end) 121f23b8eeeSSeongJae Park { 122f23b8eeeSSeongJae Park struct damon_region *region; 123f23b8eeeSSeongJae Park 124a1870944SDawei Li region = kmem_cache_alloc(damon_region_cache, GFP_KERNEL); 125f23b8eeeSSeongJae Park if (!region) 126f23b8eeeSSeongJae Park return NULL; 127f23b8eeeSSeongJae Park 128f23b8eeeSSeongJae Park region->ar.start = start; 129f23b8eeeSSeongJae Park region->ar.end = end; 130f23b8eeeSSeongJae Park region->nr_accesses = 0; 131f23b8eeeSSeongJae Park INIT_LIST_HEAD(®ion->list); 132f23b8eeeSSeongJae Park 133fda504faSSeongJae Park region->age = 0; 134fda504faSSeongJae Park region->last_nr_accesses = 0; 135fda504faSSeongJae Park 136f23b8eeeSSeongJae Park return region; 137f23b8eeeSSeongJae Park } 138f23b8eeeSSeongJae Park 139f23b8eeeSSeongJae Park void damon_add_region(struct damon_region *r, struct damon_target *t) 140f23b8eeeSSeongJae Park { 141f23b8eeeSSeongJae Park list_add_tail(&r->list, &t->regions_list); 142b9a6ac4eSSeongJae Park t->nr_regions++; 143f23b8eeeSSeongJae Park } 144f23b8eeeSSeongJae Park 145b9a6ac4eSSeongJae Park static void damon_del_region(struct damon_region *r, struct damon_target *t) 146f23b8eeeSSeongJae Park { 147f23b8eeeSSeongJae Park list_del(&r->list); 148b9a6ac4eSSeongJae Park t->nr_regions--; 149f23b8eeeSSeongJae Park } 150f23b8eeeSSeongJae Park 151f23b8eeeSSeongJae Park static void damon_free_region(struct damon_region *r) 152f23b8eeeSSeongJae Park { 153a1870944SDawei Li kmem_cache_free(damon_region_cache, r); 154f23b8eeeSSeongJae Park } 155f23b8eeeSSeongJae Park 156b9a6ac4eSSeongJae Park void damon_destroy_region(struct damon_region *r, struct damon_target *t) 157f23b8eeeSSeongJae Park { 158b9a6ac4eSSeongJae Park damon_del_region(r, t); 159f23b8eeeSSeongJae Park damon_free_region(r); 160f23b8eeeSSeongJae Park } 161f23b8eeeSSeongJae Park 162d0723bc0SSeongJae Park /* 163d0723bc0SSeongJae Park * Check whether a region is intersecting an address range 164d0723bc0SSeongJae Park * 165d0723bc0SSeongJae Park * Returns true if it is. 166d0723bc0SSeongJae Park */ 167d0723bc0SSeongJae Park static bool damon_intersect(struct damon_region *r, 168d0723bc0SSeongJae Park struct damon_addr_range *re) 169d0723bc0SSeongJae Park { 170d0723bc0SSeongJae Park return !(r->ar.end <= re->start || re->end <= r->ar.start); 171d0723bc0SSeongJae Park } 172d0723bc0SSeongJae Park 173d0723bc0SSeongJae Park /* 1749c950c22SSeongJae Park * Fill holes in regions with new regions. 1759c950c22SSeongJae Park */ 1769c950c22SSeongJae Park static int damon_fill_regions_holes(struct damon_region *first, 1779c950c22SSeongJae Park struct damon_region *last, struct damon_target *t) 1789c950c22SSeongJae Park { 1799c950c22SSeongJae Park struct damon_region *r = first; 1809c950c22SSeongJae Park 1819c950c22SSeongJae Park damon_for_each_region_from(r, t) { 1829c950c22SSeongJae Park struct damon_region *next, *newr; 1839c950c22SSeongJae Park 1849c950c22SSeongJae Park if (r == last) 1859c950c22SSeongJae Park break; 1869c950c22SSeongJae Park next = damon_next_region(r); 1879c950c22SSeongJae Park if (r->ar.end != next->ar.start) { 1889c950c22SSeongJae Park newr = damon_new_region(r->ar.end, next->ar.start); 1899c950c22SSeongJae Park if (!newr) 1909c950c22SSeongJae Park return -ENOMEM; 1919c950c22SSeongJae Park damon_insert_region(newr, r, next, t); 1929c950c22SSeongJae Park } 1939c950c22SSeongJae Park } 1949c950c22SSeongJae Park return 0; 1959c950c22SSeongJae Park } 1969c950c22SSeongJae Park 1979c950c22SSeongJae Park /* 198d0723bc0SSeongJae Park * damon_set_regions() - Set regions of a target for given address ranges. 199d0723bc0SSeongJae Park * @t: the given target. 200d0723bc0SSeongJae Park * @ranges: array of new monitoring target ranges. 201d0723bc0SSeongJae Park * @nr_ranges: length of @ranges. 202d0723bc0SSeongJae Park * 203d0723bc0SSeongJae Park * This function adds new regions to, or modify existing regions of a 204d0723bc0SSeongJae Park * monitoring target to fit in specific ranges. 205d0723bc0SSeongJae Park * 206d0723bc0SSeongJae Park * Return: 0 if success, or negative error code otherwise. 207d0723bc0SSeongJae Park */ 208d0723bc0SSeongJae Park int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges, 209d0723bc0SSeongJae Park unsigned int nr_ranges) 210d0723bc0SSeongJae Park { 211d0723bc0SSeongJae Park struct damon_region *r, *next; 212d0723bc0SSeongJae Park unsigned int i; 2139c950c22SSeongJae Park int err; 214d0723bc0SSeongJae Park 215d0723bc0SSeongJae Park /* Remove regions which are not in the new ranges */ 216d0723bc0SSeongJae Park damon_for_each_region_safe(r, next, t) { 217d0723bc0SSeongJae Park for (i = 0; i < nr_ranges; i++) { 218d0723bc0SSeongJae Park if (damon_intersect(r, &ranges[i])) 219d0723bc0SSeongJae Park break; 220d0723bc0SSeongJae Park } 221d0723bc0SSeongJae Park if (i == nr_ranges) 222d0723bc0SSeongJae Park damon_destroy_region(r, t); 223d0723bc0SSeongJae Park } 224d0723bc0SSeongJae Park 22536001cbaSKaixu Xia r = damon_first_region(t); 226d0723bc0SSeongJae Park /* Add new regions or resize existing regions to fit in the ranges */ 227d0723bc0SSeongJae Park for (i = 0; i < nr_ranges; i++) { 228d0723bc0SSeongJae Park struct damon_region *first = NULL, *last, *newr; 229d0723bc0SSeongJae Park struct damon_addr_range *range; 230d0723bc0SSeongJae Park 231d0723bc0SSeongJae Park range = &ranges[i]; 232d0723bc0SSeongJae Park /* Get the first/last regions intersecting with the range */ 23336001cbaSKaixu Xia damon_for_each_region_from(r, t) { 234d0723bc0SSeongJae Park if (damon_intersect(r, range)) { 235d0723bc0SSeongJae Park if (!first) 236d0723bc0SSeongJae Park first = r; 237d0723bc0SSeongJae Park last = r; 238d0723bc0SSeongJae Park } 239d0723bc0SSeongJae Park if (r->ar.start >= range->end) 240d0723bc0SSeongJae Park break; 241d0723bc0SSeongJae Park } 242d0723bc0SSeongJae Park if (!first) { 243d0723bc0SSeongJae Park /* no region intersects with this range */ 244d0723bc0SSeongJae Park newr = damon_new_region( 245d0723bc0SSeongJae Park ALIGN_DOWN(range->start, 246d0723bc0SSeongJae Park DAMON_MIN_REGION), 247d0723bc0SSeongJae Park ALIGN(range->end, DAMON_MIN_REGION)); 248d0723bc0SSeongJae Park if (!newr) 249d0723bc0SSeongJae Park return -ENOMEM; 250d0723bc0SSeongJae Park damon_insert_region(newr, damon_prev_region(r), r, t); 251d0723bc0SSeongJae Park } else { 252d0723bc0SSeongJae Park /* resize intersecting regions to fit in this range */ 253d0723bc0SSeongJae Park first->ar.start = ALIGN_DOWN(range->start, 254d0723bc0SSeongJae Park DAMON_MIN_REGION); 255d0723bc0SSeongJae Park last->ar.end = ALIGN(range->end, DAMON_MIN_REGION); 2569c950c22SSeongJae Park 2579c950c22SSeongJae Park /* fill possible holes in the range */ 2589c950c22SSeongJae Park err = damon_fill_regions_holes(first, last, t); 2599c950c22SSeongJae Park if (err) 2609c950c22SSeongJae Park return err; 261d0723bc0SSeongJae Park } 262d0723bc0SSeongJae Park } 263d0723bc0SSeongJae Park return 0; 264d0723bc0SSeongJae Park } 265d0723bc0SSeongJae Park 266*98def236SSeongJae Park struct damos_filter *damos_new_filter(enum damos_filter_type type, 267*98def236SSeongJae Park bool matching) 268*98def236SSeongJae Park { 269*98def236SSeongJae Park struct damos_filter *filter; 270*98def236SSeongJae Park 271*98def236SSeongJae Park filter = kmalloc(sizeof(*filter), GFP_KERNEL); 272*98def236SSeongJae Park if (!filter) 273*98def236SSeongJae Park return NULL; 274*98def236SSeongJae Park filter->type = type; 275*98def236SSeongJae Park filter->matching = matching; 276*98def236SSeongJae Park return filter; 277*98def236SSeongJae Park } 278*98def236SSeongJae Park 279*98def236SSeongJae Park void damos_add_filter(struct damos *s, struct damos_filter *f) 280*98def236SSeongJae Park { 281*98def236SSeongJae Park list_add_tail(&f->list, &s->filters); 282*98def236SSeongJae Park } 283*98def236SSeongJae Park 284*98def236SSeongJae Park static void damos_del_filter(struct damos_filter *f) 285*98def236SSeongJae Park { 286*98def236SSeongJae Park list_del(&f->list); 287*98def236SSeongJae Park } 288*98def236SSeongJae Park 289*98def236SSeongJae Park static void damos_free_filter(struct damos_filter *f) 290*98def236SSeongJae Park { 291*98def236SSeongJae Park kfree(f); 292*98def236SSeongJae Park } 293*98def236SSeongJae Park 294*98def236SSeongJae Park void damos_destroy_filter(struct damos_filter *f) 295*98def236SSeongJae Park { 296*98def236SSeongJae Park damos_del_filter(f); 297*98def236SSeongJae Park damos_free_filter(f); 298*98def236SSeongJae Park } 299*98def236SSeongJae Park 30070e0c1d1SSeongJae Park /* initialize private fields of damos_quota and return the pointer */ 30170e0c1d1SSeongJae Park static struct damos_quota *damos_quota_init_priv(struct damos_quota *quota) 30270e0c1d1SSeongJae Park { 30370e0c1d1SSeongJae Park quota->total_charged_sz = 0; 30470e0c1d1SSeongJae Park quota->total_charged_ns = 0; 30570e0c1d1SSeongJae Park quota->esz = 0; 30670e0c1d1SSeongJae Park quota->charged_sz = 0; 30770e0c1d1SSeongJae Park quota->charged_from = 0; 30870e0c1d1SSeongJae Park quota->charge_target_from = NULL; 30970e0c1d1SSeongJae Park quota->charge_addr_from = 0; 31070e0c1d1SSeongJae Park return quota; 31170e0c1d1SSeongJae Park } 31270e0c1d1SSeongJae Park 313f5a79d7cSYajun Deng struct damos *damon_new_scheme(struct damos_access_pattern *pattern, 314ee801b7dSSeongJae Park enum damos_action action, struct damos_quota *quota, 315ee801b7dSSeongJae Park struct damos_watermarks *wmarks) 3161f366e42SSeongJae Park { 3171f366e42SSeongJae Park struct damos *scheme; 3181f366e42SSeongJae Park 3191f366e42SSeongJae Park scheme = kmalloc(sizeof(*scheme), GFP_KERNEL); 3201f366e42SSeongJae Park if (!scheme) 3211f366e42SSeongJae Park return NULL; 32202f17037SSeongJae Park scheme->pattern = *pattern; 3231f366e42SSeongJae Park scheme->action = action; 324*98def236SSeongJae Park INIT_LIST_HEAD(&scheme->filters); 3250e92c2eeSSeongJae Park scheme->stat = (struct damos_stat){}; 3261f366e42SSeongJae Park INIT_LIST_HEAD(&scheme->list); 3271f366e42SSeongJae Park 32870e0c1d1SSeongJae Park scheme->quota = *(damos_quota_init_priv(quota)); 3292b8a248dSSeongJae Park 33002f17037SSeongJae Park scheme->wmarks = *wmarks; 331ee801b7dSSeongJae Park scheme->wmarks.activated = true; 332ee801b7dSSeongJae Park 3331f366e42SSeongJae Park return scheme; 3341f366e42SSeongJae Park } 3351f366e42SSeongJae Park 3361f366e42SSeongJae Park void damon_add_scheme(struct damon_ctx *ctx, struct damos *s) 3371f366e42SSeongJae Park { 3381f366e42SSeongJae Park list_add_tail(&s->list, &ctx->schemes); 3391f366e42SSeongJae Park } 3401f366e42SSeongJae Park 3411f366e42SSeongJae Park static void damon_del_scheme(struct damos *s) 3421f366e42SSeongJae Park { 3431f366e42SSeongJae Park list_del(&s->list); 3441f366e42SSeongJae Park } 3451f366e42SSeongJae Park 3461f366e42SSeongJae Park static void damon_free_scheme(struct damos *s) 3471f366e42SSeongJae Park { 3481f366e42SSeongJae Park kfree(s); 3491f366e42SSeongJae Park } 3501f366e42SSeongJae Park 3511f366e42SSeongJae Park void damon_destroy_scheme(struct damos *s) 3521f366e42SSeongJae Park { 353*98def236SSeongJae Park struct damos_filter *f, *next; 354*98def236SSeongJae Park 355*98def236SSeongJae Park damos_for_each_filter_safe(f, next, s) 356*98def236SSeongJae Park damos_destroy_filter(f); 3571f366e42SSeongJae Park damon_del_scheme(s); 3581f366e42SSeongJae Park damon_free_scheme(s); 3591f366e42SSeongJae Park } 3601f366e42SSeongJae Park 361f23b8eeeSSeongJae Park /* 362f23b8eeeSSeongJae Park * Construct a damon_target struct 363f23b8eeeSSeongJae Park * 364f23b8eeeSSeongJae Park * Returns the pointer to the new struct if success, or NULL otherwise 365f23b8eeeSSeongJae Park */ 3661971bd63SSeongJae Park struct damon_target *damon_new_target(void) 367f23b8eeeSSeongJae Park { 368f23b8eeeSSeongJae Park struct damon_target *t; 369f23b8eeeSSeongJae Park 370f23b8eeeSSeongJae Park t = kmalloc(sizeof(*t), GFP_KERNEL); 371f23b8eeeSSeongJae Park if (!t) 372f23b8eeeSSeongJae Park return NULL; 373f23b8eeeSSeongJae Park 3741971bd63SSeongJae Park t->pid = NULL; 375b9a6ac4eSSeongJae Park t->nr_regions = 0; 376f23b8eeeSSeongJae Park INIT_LIST_HEAD(&t->regions_list); 377b1f44cdaSSeongJae Park INIT_LIST_HEAD(&t->list); 378f23b8eeeSSeongJae Park 379f23b8eeeSSeongJae Park return t; 380f23b8eeeSSeongJae Park } 381f23b8eeeSSeongJae Park 382f23b8eeeSSeongJae Park void damon_add_target(struct damon_ctx *ctx, struct damon_target *t) 383f23b8eeeSSeongJae Park { 384b9a6ac4eSSeongJae Park list_add_tail(&t->list, &ctx->adaptive_targets); 385f23b8eeeSSeongJae Park } 386f23b8eeeSSeongJae Park 387b5ca3e83SXin Hao bool damon_targets_empty(struct damon_ctx *ctx) 388b5ca3e83SXin Hao { 389b5ca3e83SXin Hao return list_empty(&ctx->adaptive_targets); 390b5ca3e83SXin Hao } 391b5ca3e83SXin Hao 392f23b8eeeSSeongJae Park static void damon_del_target(struct damon_target *t) 393f23b8eeeSSeongJae Park { 394f23b8eeeSSeongJae Park list_del(&t->list); 395f23b8eeeSSeongJae Park } 396f23b8eeeSSeongJae Park 397f23b8eeeSSeongJae Park void damon_free_target(struct damon_target *t) 398f23b8eeeSSeongJae Park { 399f23b8eeeSSeongJae Park struct damon_region *r, *next; 400f23b8eeeSSeongJae Park 401f23b8eeeSSeongJae Park damon_for_each_region_safe(r, next, t) 402f23b8eeeSSeongJae Park damon_free_region(r); 403f23b8eeeSSeongJae Park kfree(t); 404f23b8eeeSSeongJae Park } 405f23b8eeeSSeongJae Park 406f23b8eeeSSeongJae Park void damon_destroy_target(struct damon_target *t) 407f23b8eeeSSeongJae Park { 408f23b8eeeSSeongJae Park damon_del_target(t); 409f23b8eeeSSeongJae Park damon_free_target(t); 410f23b8eeeSSeongJae Park } 411f23b8eeeSSeongJae Park 412b9a6ac4eSSeongJae Park unsigned int damon_nr_regions(struct damon_target *t) 413b9a6ac4eSSeongJae Park { 414b9a6ac4eSSeongJae Park return t->nr_regions; 415b9a6ac4eSSeongJae Park } 416b9a6ac4eSSeongJae Park 4172224d848SSeongJae Park struct damon_ctx *damon_new_ctx(void) 4182224d848SSeongJae Park { 4192224d848SSeongJae Park struct damon_ctx *ctx; 4202224d848SSeongJae Park 4212224d848SSeongJae Park ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); 4222224d848SSeongJae Park if (!ctx) 4232224d848SSeongJae Park return NULL; 4242224d848SSeongJae Park 425cbeaa77bSSeongJae Park ctx->attrs.sample_interval = 5 * 1000; 426cbeaa77bSSeongJae Park ctx->attrs.aggr_interval = 100 * 1000; 427cbeaa77bSSeongJae Park ctx->attrs.ops_update_interval = 60 * 1000 * 1000; 4282224d848SSeongJae Park 4292224d848SSeongJae Park ktime_get_coarse_ts64(&ctx->last_aggregation); 430f7d911c3SSeongJae Park ctx->last_ops_update = ctx->last_aggregation; 4312224d848SSeongJae Park 4322224d848SSeongJae Park mutex_init(&ctx->kdamond_lock); 4332224d848SSeongJae Park 434cbeaa77bSSeongJae Park ctx->attrs.min_nr_regions = 10; 435cbeaa77bSSeongJae Park ctx->attrs.max_nr_regions = 1000; 436b9a6ac4eSSeongJae Park 437b9a6ac4eSSeongJae Park INIT_LIST_HEAD(&ctx->adaptive_targets); 4381f366e42SSeongJae Park INIT_LIST_HEAD(&ctx->schemes); 4392224d848SSeongJae Park 4402224d848SSeongJae Park return ctx; 4412224d848SSeongJae Park } 4422224d848SSeongJae Park 443f23b8eeeSSeongJae Park static void damon_destroy_targets(struct damon_ctx *ctx) 444f23b8eeeSSeongJae Park { 445f23b8eeeSSeongJae Park struct damon_target *t, *next_t; 446f23b8eeeSSeongJae Park 447f7d911c3SSeongJae Park if (ctx->ops.cleanup) { 448f7d911c3SSeongJae Park ctx->ops.cleanup(ctx); 449f23b8eeeSSeongJae Park return; 450f23b8eeeSSeongJae Park } 451f23b8eeeSSeongJae Park 452f23b8eeeSSeongJae Park damon_for_each_target_safe(t, next_t, ctx) 453f23b8eeeSSeongJae Park damon_destroy_target(t); 454f23b8eeeSSeongJae Park } 455f23b8eeeSSeongJae Park 4562224d848SSeongJae Park void damon_destroy_ctx(struct damon_ctx *ctx) 4572224d848SSeongJae Park { 4581f366e42SSeongJae Park struct damos *s, *next_s; 4591f366e42SSeongJae Park 460f23b8eeeSSeongJae Park damon_destroy_targets(ctx); 4611f366e42SSeongJae Park 4621f366e42SSeongJae Park damon_for_each_scheme_safe(s, next_s, ctx) 4631f366e42SSeongJae Park damon_destroy_scheme(s); 4641f366e42SSeongJae Park 4652224d848SSeongJae Park kfree(ctx); 4662224d848SSeongJae Park } 4672224d848SSeongJae Park 4682224d848SSeongJae Park /** 4692224d848SSeongJae Park * damon_set_attrs() - Set attributes for the monitoring. 4702224d848SSeongJae Park * @ctx: monitoring context 471bead3b00SSeongJae Park * @attrs: monitoring attributes 4722224d848SSeongJae Park * 4732224d848SSeongJae Park * This function should not be called while the kdamond is running. 4742224d848SSeongJae Park * Every time interval is in micro-seconds. 4752224d848SSeongJae Park * 4762224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 4772224d848SSeongJae Park */ 478bead3b00SSeongJae Park int damon_set_attrs(struct damon_ctx *ctx, struct damon_attrs *attrs) 4792224d848SSeongJae Park { 480bead3b00SSeongJae Park if (attrs->min_nr_regions < 3) 481b9a6ac4eSSeongJae Park return -EINVAL; 482bead3b00SSeongJae Park if (attrs->min_nr_regions > attrs->max_nr_regions) 483b9a6ac4eSSeongJae Park return -EINVAL; 484b9a6ac4eSSeongJae Park 485bead3b00SSeongJae Park ctx->attrs = *attrs; 4862224d848SSeongJae Park return 0; 4872224d848SSeongJae Park } 4882224d848SSeongJae Park 4894bc05954SSeongJae Park /** 4901f366e42SSeongJae Park * damon_set_schemes() - Set data access monitoring based operation schemes. 4911f366e42SSeongJae Park * @ctx: monitoring context 4921f366e42SSeongJae Park * @schemes: array of the schemes 4931f366e42SSeongJae Park * @nr_schemes: number of entries in @schemes 4941f366e42SSeongJae Park * 4951f366e42SSeongJae Park * This function should not be called while the kdamond of the context is 4961f366e42SSeongJae Park * running. 4971f366e42SSeongJae Park */ 498cc713520SKaixu Xia void damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, 4991f366e42SSeongJae Park ssize_t nr_schemes) 5001f366e42SSeongJae Park { 5011f366e42SSeongJae Park struct damos *s, *next; 5021f366e42SSeongJae Park ssize_t i; 5031f366e42SSeongJae Park 5041f366e42SSeongJae Park damon_for_each_scheme_safe(s, next, ctx) 5051f366e42SSeongJae Park damon_destroy_scheme(s); 5061f366e42SSeongJae Park for (i = 0; i < nr_schemes; i++) 5071f366e42SSeongJae Park damon_add_scheme(ctx, schemes[i]); 5081f366e42SSeongJae Park } 5091f366e42SSeongJae Park 5101f366e42SSeongJae Park /** 5114bc05954SSeongJae Park * damon_nr_running_ctxs() - Return number of currently running contexts. 5124bc05954SSeongJae Park */ 5134bc05954SSeongJae Park int damon_nr_running_ctxs(void) 5144bc05954SSeongJae Park { 5154bc05954SSeongJae Park int nr_ctxs; 5164bc05954SSeongJae Park 5174bc05954SSeongJae Park mutex_lock(&damon_lock); 5184bc05954SSeongJae Park nr_ctxs = nr_running_ctxs; 5194bc05954SSeongJae Park mutex_unlock(&damon_lock); 5204bc05954SSeongJae Park 5214bc05954SSeongJae Park return nr_ctxs; 5224bc05954SSeongJae Park } 5234bc05954SSeongJae Park 524b9a6ac4eSSeongJae Park /* Returns the size upper limit for each monitoring region */ 525b9a6ac4eSSeongJae Park static unsigned long damon_region_sz_limit(struct damon_ctx *ctx) 526b9a6ac4eSSeongJae Park { 527b9a6ac4eSSeongJae Park struct damon_target *t; 528b9a6ac4eSSeongJae Park struct damon_region *r; 529b9a6ac4eSSeongJae Park unsigned long sz = 0; 530b9a6ac4eSSeongJae Park 531b9a6ac4eSSeongJae Park damon_for_each_target(t, ctx) { 532b9a6ac4eSSeongJae Park damon_for_each_region(r, t) 533ab63f63fSXin Hao sz += damon_sz_region(r); 534b9a6ac4eSSeongJae Park } 535b9a6ac4eSSeongJae Park 536cbeaa77bSSeongJae Park if (ctx->attrs.min_nr_regions) 537cbeaa77bSSeongJae Park sz /= ctx->attrs.min_nr_regions; 538b9a6ac4eSSeongJae Park if (sz < DAMON_MIN_REGION) 539b9a6ac4eSSeongJae Park sz = DAMON_MIN_REGION; 540b9a6ac4eSSeongJae Park 541b9a6ac4eSSeongJae Park return sz; 542b9a6ac4eSSeongJae Park } 543b9a6ac4eSSeongJae Park 5442224d848SSeongJae Park static int kdamond_fn(void *data); 5452224d848SSeongJae Park 5462224d848SSeongJae Park /* 5472224d848SSeongJae Park * __damon_start() - Starts monitoring with given context. 5482224d848SSeongJae Park * @ctx: monitoring context 5492224d848SSeongJae Park * 5502224d848SSeongJae Park * This function should be called while damon_lock is hold. 5512224d848SSeongJae Park * 5522224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 5532224d848SSeongJae Park */ 5542224d848SSeongJae Park static int __damon_start(struct damon_ctx *ctx) 5552224d848SSeongJae Park { 5562224d848SSeongJae Park int err = -EBUSY; 5572224d848SSeongJae Park 5582224d848SSeongJae Park mutex_lock(&ctx->kdamond_lock); 5592224d848SSeongJae Park if (!ctx->kdamond) { 5602224d848SSeongJae Park err = 0; 5612224d848SSeongJae Park ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", 5622224d848SSeongJae Park nr_running_ctxs); 5632224d848SSeongJae Park if (IS_ERR(ctx->kdamond)) { 5642224d848SSeongJae Park err = PTR_ERR(ctx->kdamond); 5657ec1992bSColin Ian King ctx->kdamond = NULL; 5662224d848SSeongJae Park } 5672224d848SSeongJae Park } 5682224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 5692224d848SSeongJae Park 5702224d848SSeongJae Park return err; 5712224d848SSeongJae Park } 5722224d848SSeongJae Park 5732224d848SSeongJae Park /** 5742224d848SSeongJae Park * damon_start() - Starts the monitorings for a given group of contexts. 5752224d848SSeongJae Park * @ctxs: an array of the pointers for contexts to start monitoring 5762224d848SSeongJae Park * @nr_ctxs: size of @ctxs 5778b9b0d33SSeongJae Park * @exclusive: exclusiveness of this contexts group 5782224d848SSeongJae Park * 5792224d848SSeongJae Park * This function starts a group of monitoring threads for a group of monitoring 5802224d848SSeongJae Park * contexts. One thread per each context is created and run in parallel. The 5818b9b0d33SSeongJae Park * caller should handle synchronization between the threads by itself. If 5828b9b0d33SSeongJae Park * @exclusive is true and a group of threads that created by other 5838b9b0d33SSeongJae Park * 'damon_start()' call is currently running, this function does nothing but 5848b9b0d33SSeongJae Park * returns -EBUSY. 5852224d848SSeongJae Park * 5862224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 5872224d848SSeongJae Park */ 5888b9b0d33SSeongJae Park int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive) 5892224d848SSeongJae Park { 5902224d848SSeongJae Park int i; 5912224d848SSeongJae Park int err = 0; 5922224d848SSeongJae Park 5932224d848SSeongJae Park mutex_lock(&damon_lock); 5948b9b0d33SSeongJae Park if ((exclusive && nr_running_ctxs) || 5958b9b0d33SSeongJae Park (!exclusive && running_exclusive_ctxs)) { 5962224d848SSeongJae Park mutex_unlock(&damon_lock); 5972224d848SSeongJae Park return -EBUSY; 5982224d848SSeongJae Park } 5992224d848SSeongJae Park 6002224d848SSeongJae Park for (i = 0; i < nr_ctxs; i++) { 6012224d848SSeongJae Park err = __damon_start(ctxs[i]); 6022224d848SSeongJae Park if (err) 6032224d848SSeongJae Park break; 6042224d848SSeongJae Park nr_running_ctxs++; 6052224d848SSeongJae Park } 6068b9b0d33SSeongJae Park if (exclusive && nr_running_ctxs) 6078b9b0d33SSeongJae Park running_exclusive_ctxs = true; 6082224d848SSeongJae Park mutex_unlock(&damon_lock); 6092224d848SSeongJae Park 6102224d848SSeongJae Park return err; 6112224d848SSeongJae Park } 6122224d848SSeongJae Park 6132224d848SSeongJae Park /* 6148b9b0d33SSeongJae Park * __damon_stop() - Stops monitoring of a given context. 6152224d848SSeongJae Park * @ctx: monitoring context 6162224d848SSeongJae Park * 6172224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 6182224d848SSeongJae Park */ 6192224d848SSeongJae Park static int __damon_stop(struct damon_ctx *ctx) 6202224d848SSeongJae Park { 6210f91d133SChangbin Du struct task_struct *tsk; 6220f91d133SChangbin Du 6232224d848SSeongJae Park mutex_lock(&ctx->kdamond_lock); 6240f91d133SChangbin Du tsk = ctx->kdamond; 6250f91d133SChangbin Du if (tsk) { 6260f91d133SChangbin Du get_task_struct(tsk); 6272224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 6280f91d133SChangbin Du kthread_stop(tsk); 6290f91d133SChangbin Du put_task_struct(tsk); 6302224d848SSeongJae Park return 0; 6312224d848SSeongJae Park } 6322224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 6332224d848SSeongJae Park 6342224d848SSeongJae Park return -EPERM; 6352224d848SSeongJae Park } 6362224d848SSeongJae Park 6372224d848SSeongJae Park /** 6382224d848SSeongJae Park * damon_stop() - Stops the monitorings for a given group of contexts. 6392224d848SSeongJae Park * @ctxs: an array of the pointers for contexts to stop monitoring 6402224d848SSeongJae Park * @nr_ctxs: size of @ctxs 6412224d848SSeongJae Park * 6422224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 6432224d848SSeongJae Park */ 6442224d848SSeongJae Park int damon_stop(struct damon_ctx **ctxs, int nr_ctxs) 6452224d848SSeongJae Park { 6462224d848SSeongJae Park int i, err = 0; 6472224d848SSeongJae Park 6482224d848SSeongJae Park for (i = 0; i < nr_ctxs; i++) { 6492224d848SSeongJae Park /* nr_running_ctxs is decremented in kdamond_fn */ 6502224d848SSeongJae Park err = __damon_stop(ctxs[i]); 6512224d848SSeongJae Park if (err) 6528b9b0d33SSeongJae Park break; 6532224d848SSeongJae Park } 6542224d848SSeongJae Park return err; 6552224d848SSeongJae Park } 6562224d848SSeongJae Park 6572224d848SSeongJae Park /* 6582224d848SSeongJae Park * damon_check_reset_time_interval() - Check if a time interval is elapsed. 6592224d848SSeongJae Park * @baseline: the time to check whether the interval has elapsed since 6602224d848SSeongJae Park * @interval: the time interval (microseconds) 6612224d848SSeongJae Park * 6622224d848SSeongJae Park * See whether the given time interval has passed since the given baseline 6632224d848SSeongJae Park * time. If so, it also updates the baseline to current time for next check. 6642224d848SSeongJae Park * 6652224d848SSeongJae Park * Return: true if the time interval has passed, or false otherwise. 6662224d848SSeongJae Park */ 6672224d848SSeongJae Park static bool damon_check_reset_time_interval(struct timespec64 *baseline, 6682224d848SSeongJae Park unsigned long interval) 6692224d848SSeongJae Park { 6702224d848SSeongJae Park struct timespec64 now; 6712224d848SSeongJae Park 6722224d848SSeongJae Park ktime_get_coarse_ts64(&now); 6732224d848SSeongJae Park if ((timespec64_to_ns(&now) - timespec64_to_ns(baseline)) < 6742224d848SSeongJae Park interval * 1000) 6752224d848SSeongJae Park return false; 6762224d848SSeongJae Park *baseline = now; 6772224d848SSeongJae Park return true; 6782224d848SSeongJae Park } 6792224d848SSeongJae Park 6802224d848SSeongJae Park /* 6812224d848SSeongJae Park * Check whether it is time to flush the aggregated information 6822224d848SSeongJae Park */ 6832224d848SSeongJae Park static bool kdamond_aggregate_interval_passed(struct damon_ctx *ctx) 6842224d848SSeongJae Park { 6852224d848SSeongJae Park return damon_check_reset_time_interval(&ctx->last_aggregation, 686cbeaa77bSSeongJae Park ctx->attrs.aggr_interval); 6872224d848SSeongJae Park } 6882224d848SSeongJae Park 6892224d848SSeongJae Park /* 690f23b8eeeSSeongJae Park * Reset the aggregated monitoring results ('nr_accesses' of each region). 691f23b8eeeSSeongJae Park */ 692f23b8eeeSSeongJae Park static void kdamond_reset_aggregated(struct damon_ctx *c) 693f23b8eeeSSeongJae Park { 694f23b8eeeSSeongJae Park struct damon_target *t; 69576fd0285SSeongJae Park unsigned int ti = 0; /* target's index */ 696f23b8eeeSSeongJae Park 697f23b8eeeSSeongJae Park damon_for_each_target(t, c) { 698f23b8eeeSSeongJae Park struct damon_region *r; 699f23b8eeeSSeongJae Park 7002fcb9362SSeongJae Park damon_for_each_region(r, t) { 70176fd0285SSeongJae Park trace_damon_aggregated(t, ti, r, damon_nr_regions(t)); 702fda504faSSeongJae Park r->last_nr_accesses = r->nr_accesses; 703f23b8eeeSSeongJae Park r->nr_accesses = 0; 704f23b8eeeSSeongJae Park } 70576fd0285SSeongJae Park ti++; 706f23b8eeeSSeongJae Park } 7072fcb9362SSeongJae Park } 708f23b8eeeSSeongJae Park 7094ed98243SKaixu Xia static void damon_split_region_at(struct damon_target *t, 7104ed98243SKaixu Xia struct damon_region *r, unsigned long sz_r); 7112b8a248dSSeongJae Park 71238683e00SSeongJae Park static bool __damos_valid_target(struct damon_region *r, struct damos *s) 71338683e00SSeongJae Park { 71438683e00SSeongJae Park unsigned long sz; 71538683e00SSeongJae Park 716ab63f63fSXin Hao sz = damon_sz_region(r); 717f5a79d7cSYajun Deng return s->pattern.min_sz_region <= sz && 718f5a79d7cSYajun Deng sz <= s->pattern.max_sz_region && 719f5a79d7cSYajun Deng s->pattern.min_nr_accesses <= r->nr_accesses && 720f5a79d7cSYajun Deng r->nr_accesses <= s->pattern.max_nr_accesses && 721f5a79d7cSYajun Deng s->pattern.min_age_region <= r->age && 722f5a79d7cSYajun Deng r->age <= s->pattern.max_age_region; 72338683e00SSeongJae Park } 72438683e00SSeongJae Park 72538683e00SSeongJae Park static bool damos_valid_target(struct damon_ctx *c, struct damon_target *t, 72638683e00SSeongJae Park struct damon_region *r, struct damos *s) 72738683e00SSeongJae Park { 72838683e00SSeongJae Park bool ret = __damos_valid_target(r, s); 72938683e00SSeongJae Park 730f7d911c3SSeongJae Park if (!ret || !s->quota.esz || !c->ops.get_scheme_score) 73138683e00SSeongJae Park return ret; 73238683e00SSeongJae Park 733f7d911c3SSeongJae Park return c->ops.get_scheme_score(c, t, r, s) >= s->quota.min_score; 73438683e00SSeongJae Park } 73538683e00SSeongJae Park 7362ea34989SSeongJae Park /* 7372ea34989SSeongJae Park * damos_skip_charged_region() - Check if the given region or starting part of 7382ea34989SSeongJae Park * it is already charged for the DAMOS quota. 7392ea34989SSeongJae Park * @t: The target of the region. 7402ea34989SSeongJae Park * @rp: The pointer to the region. 7412ea34989SSeongJae Park * @s: The scheme to be applied. 7422ea34989SSeongJae Park * 7432ea34989SSeongJae Park * If a quota of a scheme has exceeded in a quota charge window, the scheme's 7442ea34989SSeongJae Park * action would applied to only a part of the target access pattern fulfilling 7452ea34989SSeongJae Park * regions. To avoid applying the scheme action to only already applied 7462ea34989SSeongJae Park * regions, DAMON skips applying the scheme action to the regions that charged 7472ea34989SSeongJae Park * in the previous charge window. 7482ea34989SSeongJae Park * 7492ea34989SSeongJae Park * This function checks if a given region should be skipped or not for the 7502ea34989SSeongJae Park * reason. If only the starting part of the region has previously charged, 7512ea34989SSeongJae Park * this function splits the region into two so that the second one covers the 7522ea34989SSeongJae Park * area that not charged in the previous charge widnow and saves the second 7532ea34989SSeongJae Park * region in *rp and returns false, so that the caller can apply DAMON action 7542ea34989SSeongJae Park * to the second one. 7552ea34989SSeongJae Park * 7562ea34989SSeongJae Park * Return: true if the region should be entirely skipped, false otherwise. 7572ea34989SSeongJae Park */ 7582ea34989SSeongJae Park static bool damos_skip_charged_region(struct damon_target *t, 7592ea34989SSeongJae Park struct damon_region **rp, struct damos *s) 7602ea34989SSeongJae Park { 7612ea34989SSeongJae Park struct damon_region *r = *rp; 7622ea34989SSeongJae Park struct damos_quota *quota = &s->quota; 7632ea34989SSeongJae Park unsigned long sz_to_skip; 7642ea34989SSeongJae Park 7652ea34989SSeongJae Park /* Skip previously charged regions */ 7662ea34989SSeongJae Park if (quota->charge_target_from) { 7672ea34989SSeongJae Park if (t != quota->charge_target_from) 7682ea34989SSeongJae Park return true; 7692ea34989SSeongJae Park if (r == damon_last_region(t)) { 7702ea34989SSeongJae Park quota->charge_target_from = NULL; 7712ea34989SSeongJae Park quota->charge_addr_from = 0; 7722ea34989SSeongJae Park return true; 7732ea34989SSeongJae Park } 7742ea34989SSeongJae Park if (quota->charge_addr_from && 7752ea34989SSeongJae Park r->ar.end <= quota->charge_addr_from) 7762ea34989SSeongJae Park return true; 7772ea34989SSeongJae Park 7782ea34989SSeongJae Park if (quota->charge_addr_from && r->ar.start < 7792ea34989SSeongJae Park quota->charge_addr_from) { 7802ea34989SSeongJae Park sz_to_skip = ALIGN_DOWN(quota->charge_addr_from - 7812ea34989SSeongJae Park r->ar.start, DAMON_MIN_REGION); 7822ea34989SSeongJae Park if (!sz_to_skip) { 7832ea34989SSeongJae Park if (damon_sz_region(r) <= DAMON_MIN_REGION) 7842ea34989SSeongJae Park return true; 7852ea34989SSeongJae Park sz_to_skip = DAMON_MIN_REGION; 7862ea34989SSeongJae Park } 7872ea34989SSeongJae Park damon_split_region_at(t, r, sz_to_skip); 7882ea34989SSeongJae Park r = damon_next_region(r); 7892ea34989SSeongJae Park *rp = r; 7902ea34989SSeongJae Park } 7912ea34989SSeongJae Park quota->charge_target_from = NULL; 7922ea34989SSeongJae Park quota->charge_addr_from = 0; 7932ea34989SSeongJae Park } 7942ea34989SSeongJae Park return false; 7952ea34989SSeongJae Park } 7962ea34989SSeongJae Park 797d1cbbf62SSeongJae Park static void damos_update_stat(struct damos *s, 798d1cbbf62SSeongJae Park unsigned long sz_tried, unsigned long sz_applied) 799d1cbbf62SSeongJae Park { 800d1cbbf62SSeongJae Park s->stat.nr_tried++; 801d1cbbf62SSeongJae Park s->stat.sz_tried += sz_tried; 802d1cbbf62SSeongJae Park if (sz_applied) 803d1cbbf62SSeongJae Park s->stat.nr_applied++; 804d1cbbf62SSeongJae Park s->stat.sz_applied += sz_applied; 805d1cbbf62SSeongJae Park } 806d1cbbf62SSeongJae Park 807e63a30c5SSeongJae Park static void damos_apply_scheme(struct damon_ctx *c, struct damon_target *t, 808e63a30c5SSeongJae Park struct damon_region *r, struct damos *s) 8091f366e42SSeongJae Park { 8102b8a248dSSeongJae Park struct damos_quota *quota = &s->quota; 811e63a30c5SSeongJae Park unsigned long sz = damon_sz_region(r); 8121cd24303SSeongJae Park struct timespec64 begin, end; 8130e92c2eeSSeongJae Park unsigned long sz_applied = 0; 81444467bbbSSeongJae Park int err = 0; 8152b8a248dSSeongJae Park 816f7d911c3SSeongJae Park if (c->ops.apply_scheme) { 817e63a30c5SSeongJae Park if (quota->esz && quota->charged_sz + sz > quota->esz) { 8181cd24303SSeongJae Park sz = ALIGN_DOWN(quota->esz - quota->charged_sz, 8192b8a248dSSeongJae Park DAMON_MIN_REGION); 8202b8a248dSSeongJae Park if (!sz) 8212b8a248dSSeongJae Park goto update_stat; 8224ed98243SKaixu Xia damon_split_region_at(t, r, sz); 8232b8a248dSSeongJae Park } 8241cd24303SSeongJae Park ktime_get_coarse_ts64(&begin); 82544467bbbSSeongJae Park if (c->callback.before_damos_apply) 82644467bbbSSeongJae Park err = c->callback.before_damos_apply(c, t, r, s); 82744467bbbSSeongJae Park if (!err) 828f7d911c3SSeongJae Park sz_applied = c->ops.apply_scheme(c, t, r, s); 8291cd24303SSeongJae Park ktime_get_coarse_ts64(&end); 8301cd24303SSeongJae Park quota->total_charged_ns += timespec64_to_ns(&end) - 8311cd24303SSeongJae Park timespec64_to_ns(&begin); 8322b8a248dSSeongJae Park quota->charged_sz += sz; 8331cd24303SSeongJae Park if (quota->esz && quota->charged_sz >= quota->esz) { 83450585192SSeongJae Park quota->charge_target_from = t; 83550585192SSeongJae Park quota->charge_addr_from = r->ar.end + 1; 83650585192SSeongJae Park } 8372b8a248dSSeongJae Park } 8382f0b548cSSeongJae Park if (s->action != DAMOS_STAT) 8391f366e42SSeongJae Park r->age = 0; 8402b8a248dSSeongJae Park 8412b8a248dSSeongJae Park update_stat: 842d1cbbf62SSeongJae Park damos_update_stat(s, sz, sz_applied); 8431f366e42SSeongJae Park } 844e63a30c5SSeongJae Park 845e63a30c5SSeongJae Park static void damon_do_apply_schemes(struct damon_ctx *c, 846e63a30c5SSeongJae Park struct damon_target *t, 847e63a30c5SSeongJae Park struct damon_region *r) 848e63a30c5SSeongJae Park { 849e63a30c5SSeongJae Park struct damos *s; 850e63a30c5SSeongJae Park 851e63a30c5SSeongJae Park damon_for_each_scheme(s, c) { 852e63a30c5SSeongJae Park struct damos_quota *quota = &s->quota; 853e63a30c5SSeongJae Park 854e63a30c5SSeongJae Park if (!s->wmarks.activated) 855e63a30c5SSeongJae Park continue; 856e63a30c5SSeongJae Park 857e63a30c5SSeongJae Park /* Check the quota */ 858e63a30c5SSeongJae Park if (quota->esz && quota->charged_sz >= quota->esz) 859e63a30c5SSeongJae Park continue; 860e63a30c5SSeongJae Park 861e63a30c5SSeongJae Park if (damos_skip_charged_region(t, &r, s)) 862e63a30c5SSeongJae Park continue; 863e63a30c5SSeongJae Park 864e63a30c5SSeongJae Park if (!damos_valid_target(c, t, r, s)) 865e63a30c5SSeongJae Park continue; 866e63a30c5SSeongJae Park 867e63a30c5SSeongJae Park damos_apply_scheme(c, t, r, s); 868e63a30c5SSeongJae Park } 8691f366e42SSeongJae Park } 8701f366e42SSeongJae Park 8711cd24303SSeongJae Park /* Shouldn't be called if quota->ms and quota->sz are zero */ 8721cd24303SSeongJae Park static void damos_set_effective_quota(struct damos_quota *quota) 8731cd24303SSeongJae Park { 8741cd24303SSeongJae Park unsigned long throughput; 8751cd24303SSeongJae Park unsigned long esz; 8761cd24303SSeongJae Park 8771cd24303SSeongJae Park if (!quota->ms) { 8781cd24303SSeongJae Park quota->esz = quota->sz; 8791cd24303SSeongJae Park return; 8801cd24303SSeongJae Park } 8811cd24303SSeongJae Park 8821cd24303SSeongJae Park if (quota->total_charged_ns) 8831cd24303SSeongJae Park throughput = quota->total_charged_sz * 1000000 / 8841cd24303SSeongJae Park quota->total_charged_ns; 8851cd24303SSeongJae Park else 8861cd24303SSeongJae Park throughput = PAGE_SIZE * 1024; 8871cd24303SSeongJae Park esz = throughput * quota->ms; 8881cd24303SSeongJae Park 8891cd24303SSeongJae Park if (quota->sz && quota->sz < esz) 8901cd24303SSeongJae Park esz = quota->sz; 8911cd24303SSeongJae Park quota->esz = esz; 8921cd24303SSeongJae Park } 8931cd24303SSeongJae Park 894898810e5SSeongJae Park static void damos_adjust_quota(struct damon_ctx *c, struct damos *s) 8951f366e42SSeongJae Park { 8962b8a248dSSeongJae Park struct damos_quota *quota = &s->quota; 897898810e5SSeongJae Park struct damon_target *t; 898898810e5SSeongJae Park struct damon_region *r; 89938683e00SSeongJae Park unsigned long cumulated_sz; 90038683e00SSeongJae Park unsigned int score, max_score = 0; 9012b8a248dSSeongJae Park 9021cd24303SSeongJae Park if (!quota->ms && !quota->sz) 903898810e5SSeongJae Park return; 9042b8a248dSSeongJae Park 9052b8a248dSSeongJae Park /* New charge window starts */ 9062b8a248dSSeongJae Park if (time_after_eq(jiffies, quota->charged_from + 907898810e5SSeongJae Park msecs_to_jiffies(quota->reset_interval))) { 9086268eac3SSeongJae Park if (quota->esz && quota->charged_sz >= quota->esz) 9096268eac3SSeongJae Park s->stat.qt_exceeds++; 9101cd24303SSeongJae Park quota->total_charged_sz += quota->charged_sz; 9112b8a248dSSeongJae Park quota->charged_from = jiffies; 9122b8a248dSSeongJae Park quota->charged_sz = 0; 9131cd24303SSeongJae Park damos_set_effective_quota(quota); 9142b8a248dSSeongJae Park } 91538683e00SSeongJae Park 916f7d911c3SSeongJae Park if (!c->ops.get_scheme_score) 917898810e5SSeongJae Park return; 91838683e00SSeongJae Park 91938683e00SSeongJae Park /* Fill up the score histogram */ 92038683e00SSeongJae Park memset(quota->histogram, 0, sizeof(quota->histogram)); 92138683e00SSeongJae Park damon_for_each_target(t, c) { 92238683e00SSeongJae Park damon_for_each_region(r, t) { 92338683e00SSeongJae Park if (!__damos_valid_target(r, s)) 92438683e00SSeongJae Park continue; 925898810e5SSeongJae Park score = c->ops.get_scheme_score(c, t, r, s); 926ab63f63fSXin Hao quota->histogram[score] += damon_sz_region(r); 92738683e00SSeongJae Park if (score > max_score) 92838683e00SSeongJae Park max_score = score; 92938683e00SSeongJae Park } 93038683e00SSeongJae Park } 93138683e00SSeongJae Park 93238683e00SSeongJae Park /* Set the min score limit */ 93338683e00SSeongJae Park for (cumulated_sz = 0, score = max_score; ; score--) { 93438683e00SSeongJae Park cumulated_sz += quota->histogram[score]; 93538683e00SSeongJae Park if (cumulated_sz >= quota->esz || !score) 93638683e00SSeongJae Park break; 93738683e00SSeongJae Park } 93838683e00SSeongJae Park quota->min_score = score; 9392b8a248dSSeongJae Park } 9401f366e42SSeongJae Park 941898810e5SSeongJae Park static void kdamond_apply_schemes(struct damon_ctx *c) 942898810e5SSeongJae Park { 943898810e5SSeongJae Park struct damon_target *t; 944898810e5SSeongJae Park struct damon_region *r, *next_r; 945898810e5SSeongJae Park struct damos *s; 946898810e5SSeongJae Park 947898810e5SSeongJae Park damon_for_each_scheme(s, c) { 948898810e5SSeongJae Park if (!s->wmarks.activated) 949898810e5SSeongJae Park continue; 950898810e5SSeongJae Park 951898810e5SSeongJae Park damos_adjust_quota(c, s); 952898810e5SSeongJae Park } 953898810e5SSeongJae Park 9541f366e42SSeongJae Park damon_for_each_target(t, c) { 9552b8a248dSSeongJae Park damon_for_each_region_safe(r, next_r, t) 9561f366e42SSeongJae Park damon_do_apply_schemes(c, t, r); 9571f366e42SSeongJae Park } 9581f366e42SSeongJae Park } 9591f366e42SSeongJae Park 960b9a6ac4eSSeongJae Park /* 961b9a6ac4eSSeongJae Park * Merge two adjacent regions into one region 962b9a6ac4eSSeongJae Park */ 963b9a6ac4eSSeongJae Park static void damon_merge_two_regions(struct damon_target *t, 964b9a6ac4eSSeongJae Park struct damon_region *l, struct damon_region *r) 965b9a6ac4eSSeongJae Park { 966652e0446SXin Hao unsigned long sz_l = damon_sz_region(l), sz_r = damon_sz_region(r); 967b9a6ac4eSSeongJae Park 968b9a6ac4eSSeongJae Park l->nr_accesses = (l->nr_accesses * sz_l + r->nr_accesses * sz_r) / 969b9a6ac4eSSeongJae Park (sz_l + sz_r); 970fda504faSSeongJae Park l->age = (l->age * sz_l + r->age * sz_r) / (sz_l + sz_r); 971b9a6ac4eSSeongJae Park l->ar.end = r->ar.end; 972b9a6ac4eSSeongJae Park damon_destroy_region(r, t); 973b9a6ac4eSSeongJae Park } 974b9a6ac4eSSeongJae Park 975b9a6ac4eSSeongJae Park /* 976b9a6ac4eSSeongJae Park * Merge adjacent regions having similar access frequencies 977b9a6ac4eSSeongJae Park * 978b9a6ac4eSSeongJae Park * t target affected by this merge operation 979b9a6ac4eSSeongJae Park * thres '->nr_accesses' diff threshold for the merge 980b9a6ac4eSSeongJae Park * sz_limit size upper limit of each region 981b9a6ac4eSSeongJae Park */ 982b9a6ac4eSSeongJae Park static void damon_merge_regions_of(struct damon_target *t, unsigned int thres, 983b9a6ac4eSSeongJae Park unsigned long sz_limit) 984b9a6ac4eSSeongJae Park { 985b9a6ac4eSSeongJae Park struct damon_region *r, *prev = NULL, *next; 986b9a6ac4eSSeongJae Park 987b9a6ac4eSSeongJae Park damon_for_each_region_safe(r, next, t) { 988d720bbbdSXin Hao if (abs(r->nr_accesses - r->last_nr_accesses) > thres) 989fda504faSSeongJae Park r->age = 0; 990fda504faSSeongJae Park else 991fda504faSSeongJae Park r->age++; 992fda504faSSeongJae Park 993b9a6ac4eSSeongJae Park if (prev && prev->ar.end == r->ar.start && 994d720bbbdSXin Hao abs(prev->nr_accesses - r->nr_accesses) <= thres && 995652e0446SXin Hao damon_sz_region(prev) + damon_sz_region(r) <= sz_limit) 996b9a6ac4eSSeongJae Park damon_merge_two_regions(t, prev, r); 997b9a6ac4eSSeongJae Park else 998b9a6ac4eSSeongJae Park prev = r; 999b9a6ac4eSSeongJae Park } 1000b9a6ac4eSSeongJae Park } 1001b9a6ac4eSSeongJae Park 1002b9a6ac4eSSeongJae Park /* 1003b9a6ac4eSSeongJae Park * Merge adjacent regions having similar access frequencies 1004b9a6ac4eSSeongJae Park * 1005b9a6ac4eSSeongJae Park * threshold '->nr_accesses' diff threshold for the merge 1006b9a6ac4eSSeongJae Park * sz_limit size upper limit of each region 1007b9a6ac4eSSeongJae Park * 1008b9a6ac4eSSeongJae Park * This function merges monitoring target regions which are adjacent and their 1009b9a6ac4eSSeongJae Park * access frequencies are similar. This is for minimizing the monitoring 1010b9a6ac4eSSeongJae Park * overhead under the dynamically changeable access pattern. If a merge was 1011b9a6ac4eSSeongJae Park * unnecessarily made, later 'kdamond_split_regions()' will revert it. 1012b9a6ac4eSSeongJae Park */ 1013b9a6ac4eSSeongJae Park static void kdamond_merge_regions(struct damon_ctx *c, unsigned int threshold, 1014b9a6ac4eSSeongJae Park unsigned long sz_limit) 1015b9a6ac4eSSeongJae Park { 1016b9a6ac4eSSeongJae Park struct damon_target *t; 1017b9a6ac4eSSeongJae Park 1018b9a6ac4eSSeongJae Park damon_for_each_target(t, c) 1019b9a6ac4eSSeongJae Park damon_merge_regions_of(t, threshold, sz_limit); 1020b9a6ac4eSSeongJae Park } 1021b9a6ac4eSSeongJae Park 1022b9a6ac4eSSeongJae Park /* 1023b9a6ac4eSSeongJae Park * Split a region in two 1024b9a6ac4eSSeongJae Park * 1025b9a6ac4eSSeongJae Park * r the region to be split 1026b9a6ac4eSSeongJae Park * sz_r size of the first sub-region that will be made 1027b9a6ac4eSSeongJae Park */ 10284ed98243SKaixu Xia static void damon_split_region_at(struct damon_target *t, 10294ed98243SKaixu Xia struct damon_region *r, unsigned long sz_r) 1030b9a6ac4eSSeongJae Park { 1031b9a6ac4eSSeongJae Park struct damon_region *new; 1032b9a6ac4eSSeongJae Park 1033b9a6ac4eSSeongJae Park new = damon_new_region(r->ar.start + sz_r, r->ar.end); 1034b9a6ac4eSSeongJae Park if (!new) 1035b9a6ac4eSSeongJae Park return; 1036b9a6ac4eSSeongJae Park 1037b9a6ac4eSSeongJae Park r->ar.end = new->ar.start; 1038b9a6ac4eSSeongJae Park 1039fda504faSSeongJae Park new->age = r->age; 1040fda504faSSeongJae Park new->last_nr_accesses = r->last_nr_accesses; 1041fda504faSSeongJae Park 1042b9a6ac4eSSeongJae Park damon_insert_region(new, r, damon_next_region(r), t); 1043b9a6ac4eSSeongJae Park } 1044b9a6ac4eSSeongJae Park 1045b9a6ac4eSSeongJae Park /* Split every region in the given target into 'nr_subs' regions */ 10464ed98243SKaixu Xia static void damon_split_regions_of(struct damon_target *t, int nr_subs) 1047b9a6ac4eSSeongJae Park { 1048b9a6ac4eSSeongJae Park struct damon_region *r, *next; 1049b9a6ac4eSSeongJae Park unsigned long sz_region, sz_sub = 0; 1050b9a6ac4eSSeongJae Park int i; 1051b9a6ac4eSSeongJae Park 1052b9a6ac4eSSeongJae Park damon_for_each_region_safe(r, next, t) { 1053ab63f63fSXin Hao sz_region = damon_sz_region(r); 1054b9a6ac4eSSeongJae Park 1055b9a6ac4eSSeongJae Park for (i = 0; i < nr_subs - 1 && 1056b9a6ac4eSSeongJae Park sz_region > 2 * DAMON_MIN_REGION; i++) { 1057b9a6ac4eSSeongJae Park /* 1058b9a6ac4eSSeongJae Park * Randomly select size of left sub-region to be at 1059b9a6ac4eSSeongJae Park * least 10 percent and at most 90% of original region 1060b9a6ac4eSSeongJae Park */ 1061b9a6ac4eSSeongJae Park sz_sub = ALIGN_DOWN(damon_rand(1, 10) * 1062b9a6ac4eSSeongJae Park sz_region / 10, DAMON_MIN_REGION); 1063b9a6ac4eSSeongJae Park /* Do not allow blank region */ 1064b9a6ac4eSSeongJae Park if (sz_sub == 0 || sz_sub >= sz_region) 1065b9a6ac4eSSeongJae Park continue; 1066b9a6ac4eSSeongJae Park 10674ed98243SKaixu Xia damon_split_region_at(t, r, sz_sub); 1068b9a6ac4eSSeongJae Park sz_region = sz_sub; 1069b9a6ac4eSSeongJae Park } 1070b9a6ac4eSSeongJae Park } 1071b9a6ac4eSSeongJae Park } 1072b9a6ac4eSSeongJae Park 1073b9a6ac4eSSeongJae Park /* 1074b9a6ac4eSSeongJae Park * Split every target region into randomly-sized small regions 1075b9a6ac4eSSeongJae Park * 1076b9a6ac4eSSeongJae Park * This function splits every target region into random-sized small regions if 1077b9a6ac4eSSeongJae Park * current total number of the regions is equal or smaller than half of the 1078b9a6ac4eSSeongJae Park * user-specified maximum number of regions. This is for maximizing the 1079b9a6ac4eSSeongJae Park * monitoring accuracy under the dynamically changeable access patterns. If a 1080b9a6ac4eSSeongJae Park * split was unnecessarily made, later 'kdamond_merge_regions()' will revert 1081b9a6ac4eSSeongJae Park * it. 1082b9a6ac4eSSeongJae Park */ 1083b9a6ac4eSSeongJae Park static void kdamond_split_regions(struct damon_ctx *ctx) 1084b9a6ac4eSSeongJae Park { 1085b9a6ac4eSSeongJae Park struct damon_target *t; 1086b9a6ac4eSSeongJae Park unsigned int nr_regions = 0; 1087b9a6ac4eSSeongJae Park static unsigned int last_nr_regions; 1088b9a6ac4eSSeongJae Park int nr_subregions = 2; 1089b9a6ac4eSSeongJae Park 1090b9a6ac4eSSeongJae Park damon_for_each_target(t, ctx) 1091b9a6ac4eSSeongJae Park nr_regions += damon_nr_regions(t); 1092b9a6ac4eSSeongJae Park 1093cbeaa77bSSeongJae Park if (nr_regions > ctx->attrs.max_nr_regions / 2) 1094b9a6ac4eSSeongJae Park return; 1095b9a6ac4eSSeongJae Park 1096b9a6ac4eSSeongJae Park /* Maybe the middle of the region has different access frequency */ 1097b9a6ac4eSSeongJae Park if (last_nr_regions == nr_regions && 1098cbeaa77bSSeongJae Park nr_regions < ctx->attrs.max_nr_regions / 3) 1099b9a6ac4eSSeongJae Park nr_subregions = 3; 1100b9a6ac4eSSeongJae Park 1101b9a6ac4eSSeongJae Park damon_for_each_target(t, ctx) 11024ed98243SKaixu Xia damon_split_regions_of(t, nr_subregions); 1103b9a6ac4eSSeongJae Park 1104b9a6ac4eSSeongJae Park last_nr_regions = nr_regions; 1105b9a6ac4eSSeongJae Park } 1106b9a6ac4eSSeongJae Park 1107f23b8eeeSSeongJae Park /* 1108f7d911c3SSeongJae Park * Check whether it is time to check and apply the operations-related data 1109f7d911c3SSeongJae Park * structures. 11102224d848SSeongJae Park * 11112224d848SSeongJae Park * Returns true if it is. 11122224d848SSeongJae Park */ 1113f7d911c3SSeongJae Park static bool kdamond_need_update_operations(struct damon_ctx *ctx) 11142224d848SSeongJae Park { 1115f7d911c3SSeongJae Park return damon_check_reset_time_interval(&ctx->last_ops_update, 1116cbeaa77bSSeongJae Park ctx->attrs.ops_update_interval); 11172224d848SSeongJae Park } 11182224d848SSeongJae Park 11192224d848SSeongJae Park /* 11202224d848SSeongJae Park * Check whether current monitoring should be stopped 11212224d848SSeongJae Park * 11222224d848SSeongJae Park * The monitoring is stopped when either the user requested to stop, or all 11232224d848SSeongJae Park * monitoring targets are invalid. 11242224d848SSeongJae Park * 11252224d848SSeongJae Park * Returns true if need to stop current monitoring. 11262224d848SSeongJae Park */ 11272224d848SSeongJae Park static bool kdamond_need_stop(struct damon_ctx *ctx) 11282224d848SSeongJae Park { 1129f23b8eeeSSeongJae Park struct damon_target *t; 11302224d848SSeongJae Park 11310f91d133SChangbin Du if (kthread_should_stop()) 11322224d848SSeongJae Park return true; 11332224d848SSeongJae Park 1134f7d911c3SSeongJae Park if (!ctx->ops.target_valid) 11352224d848SSeongJae Park return false; 11362224d848SSeongJae Park 1137f23b8eeeSSeongJae Park damon_for_each_target(t, ctx) { 1138f7d911c3SSeongJae Park if (ctx->ops.target_valid(t)) 1139f23b8eeeSSeongJae Park return false; 1140f23b8eeeSSeongJae Park } 1141f23b8eeeSSeongJae Park 1142f23b8eeeSSeongJae Park return true; 11432224d848SSeongJae Park } 11442224d848SSeongJae Park 1145ee801b7dSSeongJae Park static unsigned long damos_wmark_metric_value(enum damos_wmark_metric metric) 1146ee801b7dSSeongJae Park { 1147ee801b7dSSeongJae Park struct sysinfo i; 1148ee801b7dSSeongJae Park 1149ee801b7dSSeongJae Park switch (metric) { 1150ee801b7dSSeongJae Park case DAMOS_WMARK_FREE_MEM_RATE: 1151ee801b7dSSeongJae Park si_meminfo(&i); 1152ee801b7dSSeongJae Park return i.freeram * 1000 / i.totalram; 1153ee801b7dSSeongJae Park default: 1154ee801b7dSSeongJae Park break; 1155ee801b7dSSeongJae Park } 1156ee801b7dSSeongJae Park return -EINVAL; 1157ee801b7dSSeongJae Park } 1158ee801b7dSSeongJae Park 1159ee801b7dSSeongJae Park /* 1160ee801b7dSSeongJae Park * Returns zero if the scheme is active. Else, returns time to wait for next 1161ee801b7dSSeongJae Park * watermark check in micro-seconds. 1162ee801b7dSSeongJae Park */ 1163ee801b7dSSeongJae Park static unsigned long damos_wmark_wait_us(struct damos *scheme) 1164ee801b7dSSeongJae Park { 1165ee801b7dSSeongJae Park unsigned long metric; 1166ee801b7dSSeongJae Park 1167ee801b7dSSeongJae Park if (scheme->wmarks.metric == DAMOS_WMARK_NONE) 1168ee801b7dSSeongJae Park return 0; 1169ee801b7dSSeongJae Park 1170ee801b7dSSeongJae Park metric = damos_wmark_metric_value(scheme->wmarks.metric); 1171ee801b7dSSeongJae Park /* higher than high watermark or lower than low watermark */ 1172ee801b7dSSeongJae Park if (metric > scheme->wmarks.high || scheme->wmarks.low > metric) { 1173ee801b7dSSeongJae Park if (scheme->wmarks.activated) 117401078655SColin Ian King pr_debug("deactivate a scheme (%d) for %s wmark\n", 1175ee801b7dSSeongJae Park scheme->action, 1176ee801b7dSSeongJae Park metric > scheme->wmarks.high ? 1177ee801b7dSSeongJae Park "high" : "low"); 1178ee801b7dSSeongJae Park scheme->wmarks.activated = false; 1179ee801b7dSSeongJae Park return scheme->wmarks.interval; 1180ee801b7dSSeongJae Park } 1181ee801b7dSSeongJae Park 1182ee801b7dSSeongJae Park /* inactive and higher than middle watermark */ 1183ee801b7dSSeongJae Park if ((scheme->wmarks.high >= metric && metric >= scheme->wmarks.mid) && 1184ee801b7dSSeongJae Park !scheme->wmarks.activated) 1185ee801b7dSSeongJae Park return scheme->wmarks.interval; 1186ee801b7dSSeongJae Park 1187ee801b7dSSeongJae Park if (!scheme->wmarks.activated) 1188ee801b7dSSeongJae Park pr_debug("activate a scheme (%d)\n", scheme->action); 1189ee801b7dSSeongJae Park scheme->wmarks.activated = true; 1190ee801b7dSSeongJae Park return 0; 1191ee801b7dSSeongJae Park } 1192ee801b7dSSeongJae Park 1193ee801b7dSSeongJae Park static void kdamond_usleep(unsigned long usecs) 1194ee801b7dSSeongJae Park { 11954de46a30SSeongJae Park /* See Documentation/timers/timers-howto.rst for the thresholds */ 11964de46a30SSeongJae Park if (usecs > 20 * USEC_PER_MSEC) 119770e92748SSeongJae Park schedule_timeout_idle(usecs_to_jiffies(usecs)); 1198ee801b7dSSeongJae Park else 119970e92748SSeongJae Park usleep_idle_range(usecs, usecs + 1); 1200ee801b7dSSeongJae Park } 1201ee801b7dSSeongJae Park 1202ee801b7dSSeongJae Park /* Returns negative error code if it's not activated but should return */ 1203ee801b7dSSeongJae Park static int kdamond_wait_activation(struct damon_ctx *ctx) 1204ee801b7dSSeongJae Park { 1205ee801b7dSSeongJae Park struct damos *s; 1206ee801b7dSSeongJae Park unsigned long wait_time; 1207ee801b7dSSeongJae Park unsigned long min_wait_time = 0; 120878049e94SJonghyeon Kim bool init_wait_time = false; 1209ee801b7dSSeongJae Park 1210ee801b7dSSeongJae Park while (!kdamond_need_stop(ctx)) { 1211ee801b7dSSeongJae Park damon_for_each_scheme(s, ctx) { 1212ee801b7dSSeongJae Park wait_time = damos_wmark_wait_us(s); 121378049e94SJonghyeon Kim if (!init_wait_time || wait_time < min_wait_time) { 121478049e94SJonghyeon Kim init_wait_time = true; 1215ee801b7dSSeongJae Park min_wait_time = wait_time; 1216ee801b7dSSeongJae Park } 121778049e94SJonghyeon Kim } 1218ee801b7dSSeongJae Park if (!min_wait_time) 1219ee801b7dSSeongJae Park return 0; 1220ee801b7dSSeongJae Park 1221ee801b7dSSeongJae Park kdamond_usleep(min_wait_time); 12226e74d2bfSSeongJae Park 12236e74d2bfSSeongJae Park if (ctx->callback.after_wmarks_check && 12246e74d2bfSSeongJae Park ctx->callback.after_wmarks_check(ctx)) 12256e74d2bfSSeongJae Park break; 1226ee801b7dSSeongJae Park } 1227ee801b7dSSeongJae Park return -EBUSY; 1228ee801b7dSSeongJae Park } 1229ee801b7dSSeongJae Park 12302224d848SSeongJae Park /* 12312224d848SSeongJae Park * The monitoring daemon that runs as a kernel thread 12322224d848SSeongJae Park */ 12332224d848SSeongJae Park static int kdamond_fn(void *data) 12342224d848SSeongJae Park { 1235cef4493fSYu Zhe struct damon_ctx *ctx = data; 1236f23b8eeeSSeongJae Park struct damon_target *t; 1237f23b8eeeSSeongJae Park struct damon_region *r, *next; 1238b9a6ac4eSSeongJae Park unsigned int max_nr_accesses = 0; 1239b9a6ac4eSSeongJae Park unsigned long sz_limit = 0; 12402224d848SSeongJae Park 124142e4cef5SChangbin Du pr_debug("kdamond (%d) starts\n", current->pid); 12422224d848SSeongJae Park 1243f7d911c3SSeongJae Park if (ctx->ops.init) 1244f7d911c3SSeongJae Park ctx->ops.init(ctx); 12452224d848SSeongJae Park if (ctx->callback.before_start && ctx->callback.before_start(ctx)) 124629454cf6SKaixu Xia goto done; 12472224d848SSeongJae Park 1248b9a6ac4eSSeongJae Park sz_limit = damon_region_sz_limit(ctx); 1249b9a6ac4eSSeongJae Park 125029454cf6SKaixu Xia while (!kdamond_need_stop(ctx)) { 125129454cf6SKaixu Xia if (kdamond_wait_activation(ctx)) 125229454cf6SKaixu Xia break; 1253ee801b7dSSeongJae Park 1254f7d911c3SSeongJae Park if (ctx->ops.prepare_access_checks) 1255f7d911c3SSeongJae Park ctx->ops.prepare_access_checks(ctx); 12562224d848SSeongJae Park if (ctx->callback.after_sampling && 125729454cf6SKaixu Xia ctx->callback.after_sampling(ctx)) 125829454cf6SKaixu Xia break; 12592224d848SSeongJae Park 1260cbeaa77bSSeongJae Park kdamond_usleep(ctx->attrs.sample_interval); 12612224d848SSeongJae Park 1262f7d911c3SSeongJae Park if (ctx->ops.check_accesses) 1263f7d911c3SSeongJae Park max_nr_accesses = ctx->ops.check_accesses(ctx); 12642224d848SSeongJae Park 12652224d848SSeongJae Park if (kdamond_aggregate_interval_passed(ctx)) { 1266b9a6ac4eSSeongJae Park kdamond_merge_regions(ctx, 1267b9a6ac4eSSeongJae Park max_nr_accesses / 10, 1268b9a6ac4eSSeongJae Park sz_limit); 12692224d848SSeongJae Park if (ctx->callback.after_aggregation && 127029454cf6SKaixu Xia ctx->callback.after_aggregation(ctx)) 127129454cf6SKaixu Xia break; 12721f366e42SSeongJae Park kdamond_apply_schemes(ctx); 1273f23b8eeeSSeongJae Park kdamond_reset_aggregated(ctx); 1274b9a6ac4eSSeongJae Park kdamond_split_regions(ctx); 1275f7d911c3SSeongJae Park if (ctx->ops.reset_aggregated) 1276f7d911c3SSeongJae Park ctx->ops.reset_aggregated(ctx); 12772224d848SSeongJae Park } 12782224d848SSeongJae Park 1279f7d911c3SSeongJae Park if (kdamond_need_update_operations(ctx)) { 1280f7d911c3SSeongJae Park if (ctx->ops.update) 1281f7d911c3SSeongJae Park ctx->ops.update(ctx); 1282b9a6ac4eSSeongJae Park sz_limit = damon_region_sz_limit(ctx); 12832224d848SSeongJae Park } 12842224d848SSeongJae Park } 128529454cf6SKaixu Xia done: 1286f23b8eeeSSeongJae Park damon_for_each_target(t, ctx) { 1287f23b8eeeSSeongJae Park damon_for_each_region_safe(r, next, t) 1288b9a6ac4eSSeongJae Park damon_destroy_region(r, t); 1289f23b8eeeSSeongJae Park } 12902224d848SSeongJae Park 12910f91d133SChangbin Du if (ctx->callback.before_terminate) 12920f91d133SChangbin Du ctx->callback.before_terminate(ctx); 1293f7d911c3SSeongJae Park if (ctx->ops.cleanup) 1294f7d911c3SSeongJae Park ctx->ops.cleanup(ctx); 12952224d848SSeongJae Park 129642e4cef5SChangbin Du pr_debug("kdamond (%d) finishes\n", current->pid); 12972224d848SSeongJae Park mutex_lock(&ctx->kdamond_lock); 12982224d848SSeongJae Park ctx->kdamond = NULL; 12992224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 13002224d848SSeongJae Park 13012224d848SSeongJae Park mutex_lock(&damon_lock); 13022224d848SSeongJae Park nr_running_ctxs--; 13038b9b0d33SSeongJae Park if (!nr_running_ctxs && running_exclusive_ctxs) 13048b9b0d33SSeongJae Park running_exclusive_ctxs = false; 13052224d848SSeongJae Park mutex_unlock(&damon_lock); 13062224d848SSeongJae Park 13075f7fe2b9SChangbin Du return 0; 13082224d848SSeongJae Park } 130917ccae8bSSeongJae Park 13100d83b2d8SXin Hao /* 13110d83b2d8SXin Hao * struct damon_system_ram_region - System RAM resource address region of 13120d83b2d8SXin Hao * [@start, @end). 13130d83b2d8SXin Hao * @start: Start address of the region (inclusive). 13140d83b2d8SXin Hao * @end: End address of the region (exclusive). 13150d83b2d8SXin Hao */ 13160d83b2d8SXin Hao struct damon_system_ram_region { 13170d83b2d8SXin Hao unsigned long start; 13180d83b2d8SXin Hao unsigned long end; 13190d83b2d8SXin Hao }; 13200d83b2d8SXin Hao 13210d83b2d8SXin Hao static int walk_system_ram(struct resource *res, void *arg) 13220d83b2d8SXin Hao { 13230d83b2d8SXin Hao struct damon_system_ram_region *a = arg; 13240d83b2d8SXin Hao 13250d83b2d8SXin Hao if (a->end - a->start < resource_size(res)) { 13260d83b2d8SXin Hao a->start = res->start; 13270d83b2d8SXin Hao a->end = res->end; 13280d83b2d8SXin Hao } 13290d83b2d8SXin Hao return 0; 13300d83b2d8SXin Hao } 13310d83b2d8SXin Hao 13320d83b2d8SXin Hao /* 13330d83b2d8SXin Hao * Find biggest 'System RAM' resource and store its start and end address in 13340d83b2d8SXin Hao * @start and @end, respectively. If no System RAM is found, returns false. 13350d83b2d8SXin Hao */ 1336233f0b31SKaixu Xia static bool damon_find_biggest_system_ram(unsigned long *start, 1337233f0b31SKaixu Xia unsigned long *end) 13380d83b2d8SXin Hao 13390d83b2d8SXin Hao { 13400d83b2d8SXin Hao struct damon_system_ram_region arg = {}; 13410d83b2d8SXin Hao 13420d83b2d8SXin Hao walk_system_ram_res(0, ULONG_MAX, &arg, walk_system_ram); 13430d83b2d8SXin Hao if (arg.end <= arg.start) 13440d83b2d8SXin Hao return false; 13450d83b2d8SXin Hao 13460d83b2d8SXin Hao *start = arg.start; 13470d83b2d8SXin Hao *end = arg.end; 13480d83b2d8SXin Hao return true; 13490d83b2d8SXin Hao } 13500d83b2d8SXin Hao 1351233f0b31SKaixu Xia /** 1352233f0b31SKaixu Xia * damon_set_region_biggest_system_ram_default() - Set the region of the given 1353233f0b31SKaixu Xia * monitoring target as requested, or biggest 'System RAM'. 1354233f0b31SKaixu Xia * @t: The monitoring target to set the region. 1355233f0b31SKaixu Xia * @start: The pointer to the start address of the region. 1356233f0b31SKaixu Xia * @end: The pointer to the end address of the region. 1357233f0b31SKaixu Xia * 1358233f0b31SKaixu Xia * This function sets the region of @t as requested by @start and @end. If the 1359233f0b31SKaixu Xia * values of @start and @end are zero, however, this function finds the biggest 1360233f0b31SKaixu Xia * 'System RAM' resource and sets the region to cover the resource. In the 1361233f0b31SKaixu Xia * latter case, this function saves the start and end addresses of the resource 1362233f0b31SKaixu Xia * in @start and @end, respectively. 1363233f0b31SKaixu Xia * 1364233f0b31SKaixu Xia * Return: 0 on success, negative error code otherwise. 1365233f0b31SKaixu Xia */ 1366233f0b31SKaixu Xia int damon_set_region_biggest_system_ram_default(struct damon_target *t, 1367233f0b31SKaixu Xia unsigned long *start, unsigned long *end) 1368233f0b31SKaixu Xia { 1369233f0b31SKaixu Xia struct damon_addr_range addr_range; 1370233f0b31SKaixu Xia 1371233f0b31SKaixu Xia if (*start > *end) 1372233f0b31SKaixu Xia return -EINVAL; 1373233f0b31SKaixu Xia 1374233f0b31SKaixu Xia if (!*start && !*end && 1375233f0b31SKaixu Xia !damon_find_biggest_system_ram(start, end)) 1376233f0b31SKaixu Xia return -EINVAL; 1377233f0b31SKaixu Xia 1378233f0b31SKaixu Xia addr_range.start = *start; 1379233f0b31SKaixu Xia addr_range.end = *end; 1380233f0b31SKaixu Xia return damon_set_regions(t, &addr_range, 1); 1381233f0b31SKaixu Xia } 1382233f0b31SKaixu Xia 1383a1870944SDawei Li static int __init damon_init(void) 1384a1870944SDawei Li { 1385a1870944SDawei Li damon_region_cache = KMEM_CACHE(damon_region, 0); 1386a1870944SDawei Li if (unlikely(!damon_region_cache)) { 1387a1870944SDawei Li pr_err("creating damon_region_cache fails\n"); 1388a1870944SDawei Li return -ENOMEM; 1389a1870944SDawei Li } 1390a1870944SDawei Li 1391a1870944SDawei Li return 0; 1392a1870944SDawei Li } 1393a1870944SDawei Li 1394a1870944SDawei Li subsys_initcall(damon_init); 1395a1870944SDawei Li 139617ccae8bSSeongJae Park #include "core-test.h" 1397