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 266f5a79d7cSYajun Deng struct damos *damon_new_scheme(struct damos_access_pattern *pattern, 267ee801b7dSSeongJae Park enum damos_action action, struct damos_quota *quota, 268ee801b7dSSeongJae Park struct damos_watermarks *wmarks) 2691f366e42SSeongJae Park { 2701f366e42SSeongJae Park struct damos *scheme; 2711f366e42SSeongJae Park 2721f366e42SSeongJae Park scheme = kmalloc(sizeof(*scheme), GFP_KERNEL); 2731f366e42SSeongJae Park if (!scheme) 2741f366e42SSeongJae Park return NULL; 275*02f17037SSeongJae Park scheme->pattern = *pattern; 2761f366e42SSeongJae Park scheme->action = action; 2770e92c2eeSSeongJae Park scheme->stat = (struct damos_stat){}; 2781f366e42SSeongJae Park INIT_LIST_HEAD(&scheme->list); 2791f366e42SSeongJae Park 280*02f17037SSeongJae Park scheme->quota = *quota; 281*02f17037SSeongJae Park /* caller might not zero-initialized the private fileds */ 2821cd24303SSeongJae Park scheme->quota.total_charged_sz = 0; 2831cd24303SSeongJae Park scheme->quota.total_charged_ns = 0; 2841cd24303SSeongJae Park scheme->quota.esz = 0; 2852b8a248dSSeongJae Park scheme->quota.charged_sz = 0; 2862b8a248dSSeongJae Park scheme->quota.charged_from = 0; 28750585192SSeongJae Park scheme->quota.charge_target_from = NULL; 28850585192SSeongJae Park scheme->quota.charge_addr_from = 0; 2892b8a248dSSeongJae Park 290*02f17037SSeongJae Park scheme->wmarks = *wmarks; 291ee801b7dSSeongJae Park scheme->wmarks.activated = true; 292ee801b7dSSeongJae Park 2931f366e42SSeongJae Park return scheme; 2941f366e42SSeongJae Park } 2951f366e42SSeongJae Park 2961f366e42SSeongJae Park void damon_add_scheme(struct damon_ctx *ctx, struct damos *s) 2971f366e42SSeongJae Park { 2981f366e42SSeongJae Park list_add_tail(&s->list, &ctx->schemes); 2991f366e42SSeongJae Park } 3001f366e42SSeongJae Park 3011f366e42SSeongJae Park static void damon_del_scheme(struct damos *s) 3021f366e42SSeongJae Park { 3031f366e42SSeongJae Park list_del(&s->list); 3041f366e42SSeongJae Park } 3051f366e42SSeongJae Park 3061f366e42SSeongJae Park static void damon_free_scheme(struct damos *s) 3071f366e42SSeongJae Park { 3081f366e42SSeongJae Park kfree(s); 3091f366e42SSeongJae Park } 3101f366e42SSeongJae Park 3111f366e42SSeongJae Park void damon_destroy_scheme(struct damos *s) 3121f366e42SSeongJae Park { 3131f366e42SSeongJae Park damon_del_scheme(s); 3141f366e42SSeongJae Park damon_free_scheme(s); 3151f366e42SSeongJae Park } 3161f366e42SSeongJae Park 317f23b8eeeSSeongJae Park /* 318f23b8eeeSSeongJae Park * Construct a damon_target struct 319f23b8eeeSSeongJae Park * 320f23b8eeeSSeongJae Park * Returns the pointer to the new struct if success, or NULL otherwise 321f23b8eeeSSeongJae Park */ 3221971bd63SSeongJae Park struct damon_target *damon_new_target(void) 323f23b8eeeSSeongJae Park { 324f23b8eeeSSeongJae Park struct damon_target *t; 325f23b8eeeSSeongJae Park 326f23b8eeeSSeongJae Park t = kmalloc(sizeof(*t), GFP_KERNEL); 327f23b8eeeSSeongJae Park if (!t) 328f23b8eeeSSeongJae Park return NULL; 329f23b8eeeSSeongJae Park 3301971bd63SSeongJae Park t->pid = NULL; 331b9a6ac4eSSeongJae Park t->nr_regions = 0; 332f23b8eeeSSeongJae Park INIT_LIST_HEAD(&t->regions_list); 333f23b8eeeSSeongJae Park 334f23b8eeeSSeongJae Park return t; 335f23b8eeeSSeongJae Park } 336f23b8eeeSSeongJae Park 337f23b8eeeSSeongJae Park void damon_add_target(struct damon_ctx *ctx, struct damon_target *t) 338f23b8eeeSSeongJae Park { 339b9a6ac4eSSeongJae Park list_add_tail(&t->list, &ctx->adaptive_targets); 340f23b8eeeSSeongJae Park } 341f23b8eeeSSeongJae Park 342b5ca3e83SXin Hao bool damon_targets_empty(struct damon_ctx *ctx) 343b5ca3e83SXin Hao { 344b5ca3e83SXin Hao return list_empty(&ctx->adaptive_targets); 345b5ca3e83SXin Hao } 346b5ca3e83SXin Hao 347f23b8eeeSSeongJae Park static void damon_del_target(struct damon_target *t) 348f23b8eeeSSeongJae Park { 349f23b8eeeSSeongJae Park list_del(&t->list); 350f23b8eeeSSeongJae Park } 351f23b8eeeSSeongJae Park 352f23b8eeeSSeongJae Park void damon_free_target(struct damon_target *t) 353f23b8eeeSSeongJae Park { 354f23b8eeeSSeongJae Park struct damon_region *r, *next; 355f23b8eeeSSeongJae Park 356f23b8eeeSSeongJae Park damon_for_each_region_safe(r, next, t) 357f23b8eeeSSeongJae Park damon_free_region(r); 358f23b8eeeSSeongJae Park kfree(t); 359f23b8eeeSSeongJae Park } 360f23b8eeeSSeongJae Park 361f23b8eeeSSeongJae Park void damon_destroy_target(struct damon_target *t) 362f23b8eeeSSeongJae Park { 363f23b8eeeSSeongJae Park damon_del_target(t); 364f23b8eeeSSeongJae Park damon_free_target(t); 365f23b8eeeSSeongJae Park } 366f23b8eeeSSeongJae Park 367b9a6ac4eSSeongJae Park unsigned int damon_nr_regions(struct damon_target *t) 368b9a6ac4eSSeongJae Park { 369b9a6ac4eSSeongJae Park return t->nr_regions; 370b9a6ac4eSSeongJae Park } 371b9a6ac4eSSeongJae Park 3722224d848SSeongJae Park struct damon_ctx *damon_new_ctx(void) 3732224d848SSeongJae Park { 3742224d848SSeongJae Park struct damon_ctx *ctx; 3752224d848SSeongJae Park 3762224d848SSeongJae Park ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); 3772224d848SSeongJae Park if (!ctx) 3782224d848SSeongJae Park return NULL; 3792224d848SSeongJae Park 3802224d848SSeongJae Park ctx->sample_interval = 5 * 1000; 3812224d848SSeongJae Park ctx->aggr_interval = 100 * 1000; 382f7d911c3SSeongJae Park ctx->ops_update_interval = 60 * 1000 * 1000; 3832224d848SSeongJae Park 3842224d848SSeongJae Park ktime_get_coarse_ts64(&ctx->last_aggregation); 385f7d911c3SSeongJae Park ctx->last_ops_update = ctx->last_aggregation; 3862224d848SSeongJae Park 3872224d848SSeongJae Park mutex_init(&ctx->kdamond_lock); 3882224d848SSeongJae Park 389b9a6ac4eSSeongJae Park ctx->min_nr_regions = 10; 390b9a6ac4eSSeongJae Park ctx->max_nr_regions = 1000; 391b9a6ac4eSSeongJae Park 392b9a6ac4eSSeongJae Park INIT_LIST_HEAD(&ctx->adaptive_targets); 3931f366e42SSeongJae Park INIT_LIST_HEAD(&ctx->schemes); 3942224d848SSeongJae Park 3952224d848SSeongJae Park return ctx; 3962224d848SSeongJae Park } 3972224d848SSeongJae Park 398f23b8eeeSSeongJae Park static void damon_destroy_targets(struct damon_ctx *ctx) 399f23b8eeeSSeongJae Park { 400f23b8eeeSSeongJae Park struct damon_target *t, *next_t; 401f23b8eeeSSeongJae Park 402f7d911c3SSeongJae Park if (ctx->ops.cleanup) { 403f7d911c3SSeongJae Park ctx->ops.cleanup(ctx); 404f23b8eeeSSeongJae Park return; 405f23b8eeeSSeongJae Park } 406f23b8eeeSSeongJae Park 407f23b8eeeSSeongJae Park damon_for_each_target_safe(t, next_t, ctx) 408f23b8eeeSSeongJae Park damon_destroy_target(t); 409f23b8eeeSSeongJae Park } 410f23b8eeeSSeongJae Park 4112224d848SSeongJae Park void damon_destroy_ctx(struct damon_ctx *ctx) 4122224d848SSeongJae Park { 4131f366e42SSeongJae Park struct damos *s, *next_s; 4141f366e42SSeongJae Park 415f23b8eeeSSeongJae Park damon_destroy_targets(ctx); 4161f366e42SSeongJae Park 4171f366e42SSeongJae Park damon_for_each_scheme_safe(s, next_s, ctx) 4181f366e42SSeongJae Park damon_destroy_scheme(s); 4191f366e42SSeongJae Park 4202224d848SSeongJae Park kfree(ctx); 4212224d848SSeongJae Park } 4222224d848SSeongJae Park 4232224d848SSeongJae Park /** 4242224d848SSeongJae Park * damon_set_attrs() - Set attributes for the monitoring. 4252224d848SSeongJae Park * @ctx: monitoring context 4262224d848SSeongJae Park * @sample_int: time interval between samplings 4272224d848SSeongJae Park * @aggr_int: time interval between aggregations 428f7d911c3SSeongJae Park * @ops_upd_int: time interval between monitoring operations updates 429b9a6ac4eSSeongJae Park * @min_nr_reg: minimal number of regions 430b9a6ac4eSSeongJae Park * @max_nr_reg: maximum number of regions 4312224d848SSeongJae Park * 4322224d848SSeongJae Park * This function should not be called while the kdamond is running. 4332224d848SSeongJae Park * Every time interval is in micro-seconds. 4342224d848SSeongJae Park * 4352224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 4362224d848SSeongJae Park */ 4372224d848SSeongJae Park int damon_set_attrs(struct damon_ctx *ctx, unsigned long sample_int, 438f7d911c3SSeongJae Park unsigned long aggr_int, unsigned long ops_upd_int, 439b9a6ac4eSSeongJae Park unsigned long min_nr_reg, unsigned long max_nr_reg) 4402224d848SSeongJae Park { 4411afaf5cbSSeongJae Park if (min_nr_reg < 3) 442b9a6ac4eSSeongJae Park return -EINVAL; 4431afaf5cbSSeongJae Park if (min_nr_reg > max_nr_reg) 444b9a6ac4eSSeongJae Park return -EINVAL; 445b9a6ac4eSSeongJae Park 4462224d848SSeongJae Park ctx->sample_interval = sample_int; 4472224d848SSeongJae Park ctx->aggr_interval = aggr_int; 448f7d911c3SSeongJae Park ctx->ops_update_interval = ops_upd_int; 449b9a6ac4eSSeongJae Park ctx->min_nr_regions = min_nr_reg; 450b9a6ac4eSSeongJae Park ctx->max_nr_regions = max_nr_reg; 4512224d848SSeongJae Park 4522224d848SSeongJae Park return 0; 4532224d848SSeongJae Park } 4542224d848SSeongJae Park 4554bc05954SSeongJae Park /** 4561f366e42SSeongJae Park * damon_set_schemes() - Set data access monitoring based operation schemes. 4571f366e42SSeongJae Park * @ctx: monitoring context 4581f366e42SSeongJae Park * @schemes: array of the schemes 4591f366e42SSeongJae Park * @nr_schemes: number of entries in @schemes 4601f366e42SSeongJae Park * 4611f366e42SSeongJae Park * This function should not be called while the kdamond of the context is 4621f366e42SSeongJae Park * running. 4631f366e42SSeongJae Park * 4641f366e42SSeongJae Park * Return: 0 if success, or negative error code otherwise. 4651f366e42SSeongJae Park */ 4661f366e42SSeongJae Park int damon_set_schemes(struct damon_ctx *ctx, struct damos **schemes, 4671f366e42SSeongJae Park ssize_t nr_schemes) 4681f366e42SSeongJae Park { 4691f366e42SSeongJae Park struct damos *s, *next; 4701f366e42SSeongJae Park ssize_t i; 4711f366e42SSeongJae Park 4721f366e42SSeongJae Park damon_for_each_scheme_safe(s, next, ctx) 4731f366e42SSeongJae Park damon_destroy_scheme(s); 4741f366e42SSeongJae Park for (i = 0; i < nr_schemes; i++) 4751f366e42SSeongJae Park damon_add_scheme(ctx, schemes[i]); 4761f366e42SSeongJae Park return 0; 4771f366e42SSeongJae Park } 4781f366e42SSeongJae Park 4791f366e42SSeongJae Park /** 4804bc05954SSeongJae Park * damon_nr_running_ctxs() - Return number of currently running contexts. 4814bc05954SSeongJae Park */ 4824bc05954SSeongJae Park int damon_nr_running_ctxs(void) 4834bc05954SSeongJae Park { 4844bc05954SSeongJae Park int nr_ctxs; 4854bc05954SSeongJae Park 4864bc05954SSeongJae Park mutex_lock(&damon_lock); 4874bc05954SSeongJae Park nr_ctxs = nr_running_ctxs; 4884bc05954SSeongJae Park mutex_unlock(&damon_lock); 4894bc05954SSeongJae Park 4904bc05954SSeongJae Park return nr_ctxs; 4914bc05954SSeongJae Park } 4924bc05954SSeongJae Park 493b9a6ac4eSSeongJae Park /* Returns the size upper limit for each monitoring region */ 494b9a6ac4eSSeongJae Park static unsigned long damon_region_sz_limit(struct damon_ctx *ctx) 495b9a6ac4eSSeongJae Park { 496b9a6ac4eSSeongJae Park struct damon_target *t; 497b9a6ac4eSSeongJae Park struct damon_region *r; 498b9a6ac4eSSeongJae Park unsigned long sz = 0; 499b9a6ac4eSSeongJae Park 500b9a6ac4eSSeongJae Park damon_for_each_target(t, ctx) { 501b9a6ac4eSSeongJae Park damon_for_each_region(r, t) 502b9a6ac4eSSeongJae Park sz += r->ar.end - r->ar.start; 503b9a6ac4eSSeongJae Park } 504b9a6ac4eSSeongJae Park 505b9a6ac4eSSeongJae Park if (ctx->min_nr_regions) 506b9a6ac4eSSeongJae Park sz /= ctx->min_nr_regions; 507b9a6ac4eSSeongJae Park if (sz < DAMON_MIN_REGION) 508b9a6ac4eSSeongJae Park sz = DAMON_MIN_REGION; 509b9a6ac4eSSeongJae Park 510b9a6ac4eSSeongJae Park return sz; 511b9a6ac4eSSeongJae Park } 512b9a6ac4eSSeongJae Park 5132224d848SSeongJae Park static int kdamond_fn(void *data); 5142224d848SSeongJae Park 5152224d848SSeongJae Park /* 5162224d848SSeongJae Park * __damon_start() - Starts monitoring with given context. 5172224d848SSeongJae Park * @ctx: monitoring context 5182224d848SSeongJae Park * 5192224d848SSeongJae Park * This function should be called while damon_lock is hold. 5202224d848SSeongJae Park * 5212224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 5222224d848SSeongJae Park */ 5232224d848SSeongJae Park static int __damon_start(struct damon_ctx *ctx) 5242224d848SSeongJae Park { 5252224d848SSeongJae Park int err = -EBUSY; 5262224d848SSeongJae Park 5272224d848SSeongJae Park mutex_lock(&ctx->kdamond_lock); 5282224d848SSeongJae Park if (!ctx->kdamond) { 5292224d848SSeongJae Park err = 0; 5302224d848SSeongJae Park ctx->kdamond = kthread_run(kdamond_fn, ctx, "kdamond.%d", 5312224d848SSeongJae Park nr_running_ctxs); 5322224d848SSeongJae Park if (IS_ERR(ctx->kdamond)) { 5332224d848SSeongJae Park err = PTR_ERR(ctx->kdamond); 5347ec1992bSColin Ian King ctx->kdamond = NULL; 5352224d848SSeongJae Park } 5362224d848SSeongJae Park } 5372224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 5382224d848SSeongJae Park 5392224d848SSeongJae Park return err; 5402224d848SSeongJae Park } 5412224d848SSeongJae Park 5422224d848SSeongJae Park /** 5432224d848SSeongJae Park * damon_start() - Starts the monitorings for a given group of contexts. 5442224d848SSeongJae Park * @ctxs: an array of the pointers for contexts to start monitoring 5452224d848SSeongJae Park * @nr_ctxs: size of @ctxs 5468b9b0d33SSeongJae Park * @exclusive: exclusiveness of this contexts group 5472224d848SSeongJae Park * 5482224d848SSeongJae Park * This function starts a group of monitoring threads for a group of monitoring 5492224d848SSeongJae Park * contexts. One thread per each context is created and run in parallel. The 5508b9b0d33SSeongJae Park * caller should handle synchronization between the threads by itself. If 5518b9b0d33SSeongJae Park * @exclusive is true and a group of threads that created by other 5528b9b0d33SSeongJae Park * 'damon_start()' call is currently running, this function does nothing but 5538b9b0d33SSeongJae Park * returns -EBUSY. 5542224d848SSeongJae Park * 5552224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 5562224d848SSeongJae Park */ 5578b9b0d33SSeongJae Park int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive) 5582224d848SSeongJae Park { 5592224d848SSeongJae Park int i; 5602224d848SSeongJae Park int err = 0; 5612224d848SSeongJae Park 5622224d848SSeongJae Park mutex_lock(&damon_lock); 5638b9b0d33SSeongJae Park if ((exclusive && nr_running_ctxs) || 5648b9b0d33SSeongJae Park (!exclusive && running_exclusive_ctxs)) { 5652224d848SSeongJae Park mutex_unlock(&damon_lock); 5662224d848SSeongJae Park return -EBUSY; 5672224d848SSeongJae Park } 5682224d848SSeongJae Park 5692224d848SSeongJae Park for (i = 0; i < nr_ctxs; i++) { 5702224d848SSeongJae Park err = __damon_start(ctxs[i]); 5712224d848SSeongJae Park if (err) 5722224d848SSeongJae Park break; 5732224d848SSeongJae Park nr_running_ctxs++; 5742224d848SSeongJae Park } 5758b9b0d33SSeongJae Park if (exclusive && nr_running_ctxs) 5768b9b0d33SSeongJae Park running_exclusive_ctxs = true; 5772224d848SSeongJae Park mutex_unlock(&damon_lock); 5782224d848SSeongJae Park 5792224d848SSeongJae Park return err; 5802224d848SSeongJae Park } 5812224d848SSeongJae Park 5822224d848SSeongJae Park /* 5838b9b0d33SSeongJae Park * __damon_stop() - Stops monitoring of a given context. 5842224d848SSeongJae Park * @ctx: monitoring context 5852224d848SSeongJae Park * 5862224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 5872224d848SSeongJae Park */ 5882224d848SSeongJae Park static int __damon_stop(struct damon_ctx *ctx) 5892224d848SSeongJae Park { 5900f91d133SChangbin Du struct task_struct *tsk; 5910f91d133SChangbin Du 5922224d848SSeongJae Park mutex_lock(&ctx->kdamond_lock); 5930f91d133SChangbin Du tsk = ctx->kdamond; 5940f91d133SChangbin Du if (tsk) { 5950f91d133SChangbin Du get_task_struct(tsk); 5962224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 5970f91d133SChangbin Du kthread_stop(tsk); 5980f91d133SChangbin Du put_task_struct(tsk); 5992224d848SSeongJae Park return 0; 6002224d848SSeongJae Park } 6012224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 6022224d848SSeongJae Park 6032224d848SSeongJae Park return -EPERM; 6042224d848SSeongJae Park } 6052224d848SSeongJae Park 6062224d848SSeongJae Park /** 6072224d848SSeongJae Park * damon_stop() - Stops the monitorings for a given group of contexts. 6082224d848SSeongJae Park * @ctxs: an array of the pointers for contexts to stop monitoring 6092224d848SSeongJae Park * @nr_ctxs: size of @ctxs 6102224d848SSeongJae Park * 6112224d848SSeongJae Park * Return: 0 on success, negative error code otherwise. 6122224d848SSeongJae Park */ 6132224d848SSeongJae Park int damon_stop(struct damon_ctx **ctxs, int nr_ctxs) 6142224d848SSeongJae Park { 6152224d848SSeongJae Park int i, err = 0; 6162224d848SSeongJae Park 6172224d848SSeongJae Park for (i = 0; i < nr_ctxs; i++) { 6182224d848SSeongJae Park /* nr_running_ctxs is decremented in kdamond_fn */ 6192224d848SSeongJae Park err = __damon_stop(ctxs[i]); 6202224d848SSeongJae Park if (err) 6218b9b0d33SSeongJae Park break; 6222224d848SSeongJae Park } 6232224d848SSeongJae Park return err; 6242224d848SSeongJae Park } 6252224d848SSeongJae Park 6262224d848SSeongJae Park /* 6272224d848SSeongJae Park * damon_check_reset_time_interval() - Check if a time interval is elapsed. 6282224d848SSeongJae Park * @baseline: the time to check whether the interval has elapsed since 6292224d848SSeongJae Park * @interval: the time interval (microseconds) 6302224d848SSeongJae Park * 6312224d848SSeongJae Park * See whether the given time interval has passed since the given baseline 6322224d848SSeongJae Park * time. If so, it also updates the baseline to current time for next check. 6332224d848SSeongJae Park * 6342224d848SSeongJae Park * Return: true if the time interval has passed, or false otherwise. 6352224d848SSeongJae Park */ 6362224d848SSeongJae Park static bool damon_check_reset_time_interval(struct timespec64 *baseline, 6372224d848SSeongJae Park unsigned long interval) 6382224d848SSeongJae Park { 6392224d848SSeongJae Park struct timespec64 now; 6402224d848SSeongJae Park 6412224d848SSeongJae Park ktime_get_coarse_ts64(&now); 6422224d848SSeongJae Park if ((timespec64_to_ns(&now) - timespec64_to_ns(baseline)) < 6432224d848SSeongJae Park interval * 1000) 6442224d848SSeongJae Park return false; 6452224d848SSeongJae Park *baseline = now; 6462224d848SSeongJae Park return true; 6472224d848SSeongJae Park } 6482224d848SSeongJae Park 6492224d848SSeongJae Park /* 6502224d848SSeongJae Park * Check whether it is time to flush the aggregated information 6512224d848SSeongJae Park */ 6522224d848SSeongJae Park static bool kdamond_aggregate_interval_passed(struct damon_ctx *ctx) 6532224d848SSeongJae Park { 6542224d848SSeongJae Park return damon_check_reset_time_interval(&ctx->last_aggregation, 6552224d848SSeongJae Park ctx->aggr_interval); 6562224d848SSeongJae Park } 6572224d848SSeongJae Park 6582224d848SSeongJae Park /* 659f23b8eeeSSeongJae Park * Reset the aggregated monitoring results ('nr_accesses' of each region). 660f23b8eeeSSeongJae Park */ 661f23b8eeeSSeongJae Park static void kdamond_reset_aggregated(struct damon_ctx *c) 662f23b8eeeSSeongJae Park { 663f23b8eeeSSeongJae Park struct damon_target *t; 66476fd0285SSeongJae Park unsigned int ti = 0; /* target's index */ 665f23b8eeeSSeongJae Park 666f23b8eeeSSeongJae Park damon_for_each_target(t, c) { 667f23b8eeeSSeongJae Park struct damon_region *r; 668f23b8eeeSSeongJae Park 6692fcb9362SSeongJae Park damon_for_each_region(r, t) { 67076fd0285SSeongJae Park trace_damon_aggregated(t, ti, r, damon_nr_regions(t)); 671fda504faSSeongJae Park r->last_nr_accesses = r->nr_accesses; 672f23b8eeeSSeongJae Park r->nr_accesses = 0; 673f23b8eeeSSeongJae Park } 67476fd0285SSeongJae Park ti++; 675f23b8eeeSSeongJae Park } 6762fcb9362SSeongJae Park } 677f23b8eeeSSeongJae Park 6784ed98243SKaixu Xia static void damon_split_region_at(struct damon_target *t, 6794ed98243SKaixu Xia struct damon_region *r, unsigned long sz_r); 6802b8a248dSSeongJae Park 68138683e00SSeongJae Park static bool __damos_valid_target(struct damon_region *r, struct damos *s) 68238683e00SSeongJae Park { 68338683e00SSeongJae Park unsigned long sz; 68438683e00SSeongJae Park 68538683e00SSeongJae Park sz = r->ar.end - r->ar.start; 686f5a79d7cSYajun Deng return s->pattern.min_sz_region <= sz && 687f5a79d7cSYajun Deng sz <= s->pattern.max_sz_region && 688f5a79d7cSYajun Deng s->pattern.min_nr_accesses <= r->nr_accesses && 689f5a79d7cSYajun Deng r->nr_accesses <= s->pattern.max_nr_accesses && 690f5a79d7cSYajun Deng s->pattern.min_age_region <= r->age && 691f5a79d7cSYajun Deng r->age <= s->pattern.max_age_region; 69238683e00SSeongJae Park } 69338683e00SSeongJae Park 69438683e00SSeongJae Park static bool damos_valid_target(struct damon_ctx *c, struct damon_target *t, 69538683e00SSeongJae Park struct damon_region *r, struct damos *s) 69638683e00SSeongJae Park { 69738683e00SSeongJae Park bool ret = __damos_valid_target(r, s); 69838683e00SSeongJae Park 699f7d911c3SSeongJae Park if (!ret || !s->quota.esz || !c->ops.get_scheme_score) 70038683e00SSeongJae Park return ret; 70138683e00SSeongJae Park 702f7d911c3SSeongJae Park return c->ops.get_scheme_score(c, t, r, s) >= s->quota.min_score; 70338683e00SSeongJae Park } 70438683e00SSeongJae Park 7051f366e42SSeongJae Park static void damon_do_apply_schemes(struct damon_ctx *c, 7061f366e42SSeongJae Park struct damon_target *t, 7071f366e42SSeongJae Park struct damon_region *r) 7081f366e42SSeongJae Park { 7091f366e42SSeongJae Park struct damos *s; 7101f366e42SSeongJae Park 7111f366e42SSeongJae Park damon_for_each_scheme(s, c) { 7122b8a248dSSeongJae Park struct damos_quota *quota = &s->quota; 7132b8a248dSSeongJae Park unsigned long sz = r->ar.end - r->ar.start; 7141cd24303SSeongJae Park struct timespec64 begin, end; 7150e92c2eeSSeongJae Park unsigned long sz_applied = 0; 7162b8a248dSSeongJae Park 717ee801b7dSSeongJae Park if (!s->wmarks.activated) 718ee801b7dSSeongJae Park continue; 719ee801b7dSSeongJae Park 7202b8a248dSSeongJae Park /* Check the quota */ 7211cd24303SSeongJae Park if (quota->esz && quota->charged_sz >= quota->esz) 7222b8a248dSSeongJae Park continue; 7232b8a248dSSeongJae Park 72450585192SSeongJae Park /* Skip previously charged regions */ 72550585192SSeongJae Park if (quota->charge_target_from) { 72650585192SSeongJae Park if (t != quota->charge_target_from) 72750585192SSeongJae Park continue; 72850585192SSeongJae Park if (r == damon_last_region(t)) { 72950585192SSeongJae Park quota->charge_target_from = NULL; 73050585192SSeongJae Park quota->charge_addr_from = 0; 73150585192SSeongJae Park continue; 73250585192SSeongJae Park } 73350585192SSeongJae Park if (quota->charge_addr_from && 73450585192SSeongJae Park r->ar.end <= quota->charge_addr_from) 73550585192SSeongJae Park continue; 73650585192SSeongJae Park 73750585192SSeongJae Park if (quota->charge_addr_from && r->ar.start < 73850585192SSeongJae Park quota->charge_addr_from) { 73950585192SSeongJae Park sz = ALIGN_DOWN(quota->charge_addr_from - 74050585192SSeongJae Park r->ar.start, DAMON_MIN_REGION); 74150585192SSeongJae Park if (!sz) { 74250585192SSeongJae Park if (r->ar.end - r->ar.start <= 74350585192SSeongJae Park DAMON_MIN_REGION) 74450585192SSeongJae Park continue; 74550585192SSeongJae Park sz = DAMON_MIN_REGION; 74650585192SSeongJae Park } 7474ed98243SKaixu Xia damon_split_region_at(t, r, sz); 74850585192SSeongJae Park r = damon_next_region(r); 74950585192SSeongJae Park sz = r->ar.end - r->ar.start; 75050585192SSeongJae Park } 75150585192SSeongJae Park quota->charge_target_from = NULL; 75250585192SSeongJae Park quota->charge_addr_from = 0; 75350585192SSeongJae Park } 75450585192SSeongJae Park 75538683e00SSeongJae Park if (!damos_valid_target(c, t, r, s)) 7561f366e42SSeongJae Park continue; 7572b8a248dSSeongJae Park 7582b8a248dSSeongJae Park /* Apply the scheme */ 759f7d911c3SSeongJae Park if (c->ops.apply_scheme) { 7601cd24303SSeongJae Park if (quota->esz && 7611cd24303SSeongJae Park quota->charged_sz + sz > quota->esz) { 7621cd24303SSeongJae Park sz = ALIGN_DOWN(quota->esz - quota->charged_sz, 7632b8a248dSSeongJae Park DAMON_MIN_REGION); 7642b8a248dSSeongJae Park if (!sz) 7652b8a248dSSeongJae Park goto update_stat; 7664ed98243SKaixu Xia damon_split_region_at(t, r, sz); 7672b8a248dSSeongJae Park } 7681cd24303SSeongJae Park ktime_get_coarse_ts64(&begin); 769f7d911c3SSeongJae Park sz_applied = c->ops.apply_scheme(c, t, r, s); 7701cd24303SSeongJae Park ktime_get_coarse_ts64(&end); 7711cd24303SSeongJae Park quota->total_charged_ns += timespec64_to_ns(&end) - 7721cd24303SSeongJae Park timespec64_to_ns(&begin); 7732b8a248dSSeongJae Park quota->charged_sz += sz; 7741cd24303SSeongJae Park if (quota->esz && quota->charged_sz >= quota->esz) { 77550585192SSeongJae Park quota->charge_target_from = t; 77650585192SSeongJae Park quota->charge_addr_from = r->ar.end + 1; 77750585192SSeongJae Park } 7782b8a248dSSeongJae Park } 7792f0b548cSSeongJae Park if (s->action != DAMOS_STAT) 7801f366e42SSeongJae Park r->age = 0; 7812b8a248dSSeongJae Park 7822b8a248dSSeongJae Park update_stat: 7830e92c2eeSSeongJae Park s->stat.nr_tried++; 7840e92c2eeSSeongJae Park s->stat.sz_tried += sz; 7850e92c2eeSSeongJae Park if (sz_applied) 7860e92c2eeSSeongJae Park s->stat.nr_applied++; 7870e92c2eeSSeongJae Park s->stat.sz_applied += sz_applied; 7881f366e42SSeongJae Park } 7891f366e42SSeongJae Park } 7901f366e42SSeongJae Park 7911cd24303SSeongJae Park /* Shouldn't be called if quota->ms and quota->sz are zero */ 7921cd24303SSeongJae Park static void damos_set_effective_quota(struct damos_quota *quota) 7931cd24303SSeongJae Park { 7941cd24303SSeongJae Park unsigned long throughput; 7951cd24303SSeongJae Park unsigned long esz; 7961cd24303SSeongJae Park 7971cd24303SSeongJae Park if (!quota->ms) { 7981cd24303SSeongJae Park quota->esz = quota->sz; 7991cd24303SSeongJae Park return; 8001cd24303SSeongJae Park } 8011cd24303SSeongJae Park 8021cd24303SSeongJae Park if (quota->total_charged_ns) 8031cd24303SSeongJae Park throughput = quota->total_charged_sz * 1000000 / 8041cd24303SSeongJae Park quota->total_charged_ns; 8051cd24303SSeongJae Park else 8061cd24303SSeongJae Park throughput = PAGE_SIZE * 1024; 8071cd24303SSeongJae Park esz = throughput * quota->ms; 8081cd24303SSeongJae Park 8091cd24303SSeongJae Park if (quota->sz && quota->sz < esz) 8101cd24303SSeongJae Park esz = quota->sz; 8111cd24303SSeongJae Park quota->esz = esz; 8121cd24303SSeongJae Park } 8131cd24303SSeongJae Park 8141f366e42SSeongJae Park static void kdamond_apply_schemes(struct damon_ctx *c) 8151f366e42SSeongJae Park { 8161f366e42SSeongJae Park struct damon_target *t; 8172b8a248dSSeongJae Park struct damon_region *r, *next_r; 8182b8a248dSSeongJae Park struct damos *s; 8192b8a248dSSeongJae Park 8202b8a248dSSeongJae Park damon_for_each_scheme(s, c) { 8212b8a248dSSeongJae Park struct damos_quota *quota = &s->quota; 82238683e00SSeongJae Park unsigned long cumulated_sz; 82338683e00SSeongJae Park unsigned int score, max_score = 0; 8242b8a248dSSeongJae Park 825ee801b7dSSeongJae Park if (!s->wmarks.activated) 826ee801b7dSSeongJae Park continue; 827ee801b7dSSeongJae Park 8281cd24303SSeongJae Park if (!quota->ms && !quota->sz) 8292b8a248dSSeongJae Park continue; 8302b8a248dSSeongJae Park 8312b8a248dSSeongJae Park /* New charge window starts */ 8322b8a248dSSeongJae Park if (time_after_eq(jiffies, quota->charged_from + 8332b8a248dSSeongJae Park msecs_to_jiffies( 8342b8a248dSSeongJae Park quota->reset_interval))) { 8356268eac3SSeongJae Park if (quota->esz && quota->charged_sz >= quota->esz) 8366268eac3SSeongJae Park s->stat.qt_exceeds++; 8371cd24303SSeongJae Park quota->total_charged_sz += quota->charged_sz; 8382b8a248dSSeongJae Park quota->charged_from = jiffies; 8392b8a248dSSeongJae Park quota->charged_sz = 0; 8401cd24303SSeongJae Park damos_set_effective_quota(quota); 8412b8a248dSSeongJae Park } 84238683e00SSeongJae Park 843f7d911c3SSeongJae Park if (!c->ops.get_scheme_score) 84438683e00SSeongJae Park continue; 84538683e00SSeongJae Park 84638683e00SSeongJae Park /* Fill up the score histogram */ 84738683e00SSeongJae Park memset(quota->histogram, 0, sizeof(quota->histogram)); 84838683e00SSeongJae Park damon_for_each_target(t, c) { 84938683e00SSeongJae Park damon_for_each_region(r, t) { 85038683e00SSeongJae Park if (!__damos_valid_target(r, s)) 85138683e00SSeongJae Park continue; 852f7d911c3SSeongJae Park score = c->ops.get_scheme_score( 85338683e00SSeongJae Park c, t, r, s); 85438683e00SSeongJae Park quota->histogram[score] += 85538683e00SSeongJae Park r->ar.end - r->ar.start; 85638683e00SSeongJae Park if (score > max_score) 85738683e00SSeongJae Park max_score = score; 85838683e00SSeongJae Park } 85938683e00SSeongJae Park } 86038683e00SSeongJae Park 86138683e00SSeongJae Park /* Set the min score limit */ 86238683e00SSeongJae Park for (cumulated_sz = 0, score = max_score; ; score--) { 86338683e00SSeongJae Park cumulated_sz += quota->histogram[score]; 86438683e00SSeongJae Park if (cumulated_sz >= quota->esz || !score) 86538683e00SSeongJae Park break; 86638683e00SSeongJae Park } 86738683e00SSeongJae Park quota->min_score = score; 8682b8a248dSSeongJae Park } 8691f366e42SSeongJae Park 8701f366e42SSeongJae Park damon_for_each_target(t, c) { 8712b8a248dSSeongJae Park damon_for_each_region_safe(r, next_r, t) 8721f366e42SSeongJae Park damon_do_apply_schemes(c, t, r); 8731f366e42SSeongJae Park } 8741f366e42SSeongJae Park } 8751f366e42SSeongJae Park 87688f86dcfSSeongJae Park static inline unsigned long sz_damon_region(struct damon_region *r) 87788f86dcfSSeongJae Park { 87888f86dcfSSeongJae Park return r->ar.end - r->ar.start; 87988f86dcfSSeongJae Park } 880b9a6ac4eSSeongJae Park 881b9a6ac4eSSeongJae Park /* 882b9a6ac4eSSeongJae Park * Merge two adjacent regions into one region 883b9a6ac4eSSeongJae Park */ 884b9a6ac4eSSeongJae Park static void damon_merge_two_regions(struct damon_target *t, 885b9a6ac4eSSeongJae Park struct damon_region *l, struct damon_region *r) 886b9a6ac4eSSeongJae Park { 887b9a6ac4eSSeongJae Park unsigned long sz_l = sz_damon_region(l), sz_r = sz_damon_region(r); 888b9a6ac4eSSeongJae Park 889b9a6ac4eSSeongJae Park l->nr_accesses = (l->nr_accesses * sz_l + r->nr_accesses * sz_r) / 890b9a6ac4eSSeongJae Park (sz_l + sz_r); 891fda504faSSeongJae Park l->age = (l->age * sz_l + r->age * sz_r) / (sz_l + sz_r); 892b9a6ac4eSSeongJae Park l->ar.end = r->ar.end; 893b9a6ac4eSSeongJae Park damon_destroy_region(r, t); 894b9a6ac4eSSeongJae Park } 895b9a6ac4eSSeongJae Park 896b9a6ac4eSSeongJae Park /* 897b9a6ac4eSSeongJae Park * Merge adjacent regions having similar access frequencies 898b9a6ac4eSSeongJae Park * 899b9a6ac4eSSeongJae Park * t target affected by this merge operation 900b9a6ac4eSSeongJae Park * thres '->nr_accesses' diff threshold for the merge 901b9a6ac4eSSeongJae Park * sz_limit size upper limit of each region 902b9a6ac4eSSeongJae Park */ 903b9a6ac4eSSeongJae Park static void damon_merge_regions_of(struct damon_target *t, unsigned int thres, 904b9a6ac4eSSeongJae Park unsigned long sz_limit) 905b9a6ac4eSSeongJae Park { 906b9a6ac4eSSeongJae Park struct damon_region *r, *prev = NULL, *next; 907b9a6ac4eSSeongJae Park 908b9a6ac4eSSeongJae Park damon_for_each_region_safe(r, next, t) { 909d720bbbdSXin Hao if (abs(r->nr_accesses - r->last_nr_accesses) > thres) 910fda504faSSeongJae Park r->age = 0; 911fda504faSSeongJae Park else 912fda504faSSeongJae Park r->age++; 913fda504faSSeongJae Park 914b9a6ac4eSSeongJae Park if (prev && prev->ar.end == r->ar.start && 915d720bbbdSXin Hao abs(prev->nr_accesses - r->nr_accesses) <= thres && 916b9a6ac4eSSeongJae Park sz_damon_region(prev) + sz_damon_region(r) <= sz_limit) 917b9a6ac4eSSeongJae Park damon_merge_two_regions(t, prev, r); 918b9a6ac4eSSeongJae Park else 919b9a6ac4eSSeongJae Park prev = r; 920b9a6ac4eSSeongJae Park } 921b9a6ac4eSSeongJae Park } 922b9a6ac4eSSeongJae Park 923b9a6ac4eSSeongJae Park /* 924b9a6ac4eSSeongJae Park * Merge adjacent regions having similar access frequencies 925b9a6ac4eSSeongJae Park * 926b9a6ac4eSSeongJae Park * threshold '->nr_accesses' diff threshold for the merge 927b9a6ac4eSSeongJae Park * sz_limit size upper limit of each region 928b9a6ac4eSSeongJae Park * 929b9a6ac4eSSeongJae Park * This function merges monitoring target regions which are adjacent and their 930b9a6ac4eSSeongJae Park * access frequencies are similar. This is for minimizing the monitoring 931b9a6ac4eSSeongJae Park * overhead under the dynamically changeable access pattern. If a merge was 932b9a6ac4eSSeongJae Park * unnecessarily made, later 'kdamond_split_regions()' will revert it. 933b9a6ac4eSSeongJae Park */ 934b9a6ac4eSSeongJae Park static void kdamond_merge_regions(struct damon_ctx *c, unsigned int threshold, 935b9a6ac4eSSeongJae Park unsigned long sz_limit) 936b9a6ac4eSSeongJae Park { 937b9a6ac4eSSeongJae Park struct damon_target *t; 938b9a6ac4eSSeongJae Park 939b9a6ac4eSSeongJae Park damon_for_each_target(t, c) 940b9a6ac4eSSeongJae Park damon_merge_regions_of(t, threshold, sz_limit); 941b9a6ac4eSSeongJae Park } 942b9a6ac4eSSeongJae Park 943b9a6ac4eSSeongJae Park /* 944b9a6ac4eSSeongJae Park * Split a region in two 945b9a6ac4eSSeongJae Park * 946b9a6ac4eSSeongJae Park * r the region to be split 947b9a6ac4eSSeongJae Park * sz_r size of the first sub-region that will be made 948b9a6ac4eSSeongJae Park */ 9494ed98243SKaixu Xia static void damon_split_region_at(struct damon_target *t, 9504ed98243SKaixu Xia struct damon_region *r, unsigned long sz_r) 951b9a6ac4eSSeongJae Park { 952b9a6ac4eSSeongJae Park struct damon_region *new; 953b9a6ac4eSSeongJae Park 954b9a6ac4eSSeongJae Park new = damon_new_region(r->ar.start + sz_r, r->ar.end); 955b9a6ac4eSSeongJae Park if (!new) 956b9a6ac4eSSeongJae Park return; 957b9a6ac4eSSeongJae Park 958b9a6ac4eSSeongJae Park r->ar.end = new->ar.start; 959b9a6ac4eSSeongJae Park 960fda504faSSeongJae Park new->age = r->age; 961fda504faSSeongJae Park new->last_nr_accesses = r->last_nr_accesses; 962fda504faSSeongJae Park 963b9a6ac4eSSeongJae Park damon_insert_region(new, r, damon_next_region(r), t); 964b9a6ac4eSSeongJae Park } 965b9a6ac4eSSeongJae Park 966b9a6ac4eSSeongJae Park /* Split every region in the given target into 'nr_subs' regions */ 9674ed98243SKaixu Xia static void damon_split_regions_of(struct damon_target *t, int nr_subs) 968b9a6ac4eSSeongJae Park { 969b9a6ac4eSSeongJae Park struct damon_region *r, *next; 970b9a6ac4eSSeongJae Park unsigned long sz_region, sz_sub = 0; 971b9a6ac4eSSeongJae Park int i; 972b9a6ac4eSSeongJae Park 973b9a6ac4eSSeongJae Park damon_for_each_region_safe(r, next, t) { 974b9a6ac4eSSeongJae Park sz_region = r->ar.end - r->ar.start; 975b9a6ac4eSSeongJae Park 976b9a6ac4eSSeongJae Park for (i = 0; i < nr_subs - 1 && 977b9a6ac4eSSeongJae Park sz_region > 2 * DAMON_MIN_REGION; i++) { 978b9a6ac4eSSeongJae Park /* 979b9a6ac4eSSeongJae Park * Randomly select size of left sub-region to be at 980b9a6ac4eSSeongJae Park * least 10 percent and at most 90% of original region 981b9a6ac4eSSeongJae Park */ 982b9a6ac4eSSeongJae Park sz_sub = ALIGN_DOWN(damon_rand(1, 10) * 983b9a6ac4eSSeongJae Park sz_region / 10, DAMON_MIN_REGION); 984b9a6ac4eSSeongJae Park /* Do not allow blank region */ 985b9a6ac4eSSeongJae Park if (sz_sub == 0 || sz_sub >= sz_region) 986b9a6ac4eSSeongJae Park continue; 987b9a6ac4eSSeongJae Park 9884ed98243SKaixu Xia damon_split_region_at(t, r, sz_sub); 989b9a6ac4eSSeongJae Park sz_region = sz_sub; 990b9a6ac4eSSeongJae Park } 991b9a6ac4eSSeongJae Park } 992b9a6ac4eSSeongJae Park } 993b9a6ac4eSSeongJae Park 994b9a6ac4eSSeongJae Park /* 995b9a6ac4eSSeongJae Park * Split every target region into randomly-sized small regions 996b9a6ac4eSSeongJae Park * 997b9a6ac4eSSeongJae Park * This function splits every target region into random-sized small regions if 998b9a6ac4eSSeongJae Park * current total number of the regions is equal or smaller than half of the 999b9a6ac4eSSeongJae Park * user-specified maximum number of regions. This is for maximizing the 1000b9a6ac4eSSeongJae Park * monitoring accuracy under the dynamically changeable access patterns. If a 1001b9a6ac4eSSeongJae Park * split was unnecessarily made, later 'kdamond_merge_regions()' will revert 1002b9a6ac4eSSeongJae Park * it. 1003b9a6ac4eSSeongJae Park */ 1004b9a6ac4eSSeongJae Park static void kdamond_split_regions(struct damon_ctx *ctx) 1005b9a6ac4eSSeongJae Park { 1006b9a6ac4eSSeongJae Park struct damon_target *t; 1007b9a6ac4eSSeongJae Park unsigned int nr_regions = 0; 1008b9a6ac4eSSeongJae Park static unsigned int last_nr_regions; 1009b9a6ac4eSSeongJae Park int nr_subregions = 2; 1010b9a6ac4eSSeongJae Park 1011b9a6ac4eSSeongJae Park damon_for_each_target(t, ctx) 1012b9a6ac4eSSeongJae Park nr_regions += damon_nr_regions(t); 1013b9a6ac4eSSeongJae Park 1014b9a6ac4eSSeongJae Park if (nr_regions > ctx->max_nr_regions / 2) 1015b9a6ac4eSSeongJae Park return; 1016b9a6ac4eSSeongJae Park 1017b9a6ac4eSSeongJae Park /* Maybe the middle of the region has different access frequency */ 1018b9a6ac4eSSeongJae Park if (last_nr_regions == nr_regions && 1019b9a6ac4eSSeongJae Park nr_regions < ctx->max_nr_regions / 3) 1020b9a6ac4eSSeongJae Park nr_subregions = 3; 1021b9a6ac4eSSeongJae Park 1022b9a6ac4eSSeongJae Park damon_for_each_target(t, ctx) 10234ed98243SKaixu Xia damon_split_regions_of(t, nr_subregions); 1024b9a6ac4eSSeongJae Park 1025b9a6ac4eSSeongJae Park last_nr_regions = nr_regions; 1026b9a6ac4eSSeongJae Park } 1027b9a6ac4eSSeongJae Park 1028f23b8eeeSSeongJae Park /* 1029f7d911c3SSeongJae Park * Check whether it is time to check and apply the operations-related data 1030f7d911c3SSeongJae Park * structures. 10312224d848SSeongJae Park * 10322224d848SSeongJae Park * Returns true if it is. 10332224d848SSeongJae Park */ 1034f7d911c3SSeongJae Park static bool kdamond_need_update_operations(struct damon_ctx *ctx) 10352224d848SSeongJae Park { 1036f7d911c3SSeongJae Park return damon_check_reset_time_interval(&ctx->last_ops_update, 1037f7d911c3SSeongJae Park ctx->ops_update_interval); 10382224d848SSeongJae Park } 10392224d848SSeongJae Park 10402224d848SSeongJae Park /* 10412224d848SSeongJae Park * Check whether current monitoring should be stopped 10422224d848SSeongJae Park * 10432224d848SSeongJae Park * The monitoring is stopped when either the user requested to stop, or all 10442224d848SSeongJae Park * monitoring targets are invalid. 10452224d848SSeongJae Park * 10462224d848SSeongJae Park * Returns true if need to stop current monitoring. 10472224d848SSeongJae Park */ 10482224d848SSeongJae Park static bool kdamond_need_stop(struct damon_ctx *ctx) 10492224d848SSeongJae Park { 1050f23b8eeeSSeongJae Park struct damon_target *t; 10512224d848SSeongJae Park 10520f91d133SChangbin Du if (kthread_should_stop()) 10532224d848SSeongJae Park return true; 10542224d848SSeongJae Park 1055f7d911c3SSeongJae Park if (!ctx->ops.target_valid) 10562224d848SSeongJae Park return false; 10572224d848SSeongJae Park 1058f23b8eeeSSeongJae Park damon_for_each_target(t, ctx) { 1059f7d911c3SSeongJae Park if (ctx->ops.target_valid(t)) 1060f23b8eeeSSeongJae Park return false; 1061f23b8eeeSSeongJae Park } 1062f23b8eeeSSeongJae Park 1063f23b8eeeSSeongJae Park return true; 10642224d848SSeongJae Park } 10652224d848SSeongJae Park 1066ee801b7dSSeongJae Park static unsigned long damos_wmark_metric_value(enum damos_wmark_metric metric) 1067ee801b7dSSeongJae Park { 1068ee801b7dSSeongJae Park struct sysinfo i; 1069ee801b7dSSeongJae Park 1070ee801b7dSSeongJae Park switch (metric) { 1071ee801b7dSSeongJae Park case DAMOS_WMARK_FREE_MEM_RATE: 1072ee801b7dSSeongJae Park si_meminfo(&i); 1073ee801b7dSSeongJae Park return i.freeram * 1000 / i.totalram; 1074ee801b7dSSeongJae Park default: 1075ee801b7dSSeongJae Park break; 1076ee801b7dSSeongJae Park } 1077ee801b7dSSeongJae Park return -EINVAL; 1078ee801b7dSSeongJae Park } 1079ee801b7dSSeongJae Park 1080ee801b7dSSeongJae Park /* 1081ee801b7dSSeongJae Park * Returns zero if the scheme is active. Else, returns time to wait for next 1082ee801b7dSSeongJae Park * watermark check in micro-seconds. 1083ee801b7dSSeongJae Park */ 1084ee801b7dSSeongJae Park static unsigned long damos_wmark_wait_us(struct damos *scheme) 1085ee801b7dSSeongJae Park { 1086ee801b7dSSeongJae Park unsigned long metric; 1087ee801b7dSSeongJae Park 1088ee801b7dSSeongJae Park if (scheme->wmarks.metric == DAMOS_WMARK_NONE) 1089ee801b7dSSeongJae Park return 0; 1090ee801b7dSSeongJae Park 1091ee801b7dSSeongJae Park metric = damos_wmark_metric_value(scheme->wmarks.metric); 1092ee801b7dSSeongJae Park /* higher than high watermark or lower than low watermark */ 1093ee801b7dSSeongJae Park if (metric > scheme->wmarks.high || scheme->wmarks.low > metric) { 1094ee801b7dSSeongJae Park if (scheme->wmarks.activated) 109501078655SColin Ian King pr_debug("deactivate a scheme (%d) for %s wmark\n", 1096ee801b7dSSeongJae Park scheme->action, 1097ee801b7dSSeongJae Park metric > scheme->wmarks.high ? 1098ee801b7dSSeongJae Park "high" : "low"); 1099ee801b7dSSeongJae Park scheme->wmarks.activated = false; 1100ee801b7dSSeongJae Park return scheme->wmarks.interval; 1101ee801b7dSSeongJae Park } 1102ee801b7dSSeongJae Park 1103ee801b7dSSeongJae Park /* inactive and higher than middle watermark */ 1104ee801b7dSSeongJae Park if ((scheme->wmarks.high >= metric && metric >= scheme->wmarks.mid) && 1105ee801b7dSSeongJae Park !scheme->wmarks.activated) 1106ee801b7dSSeongJae Park return scheme->wmarks.interval; 1107ee801b7dSSeongJae Park 1108ee801b7dSSeongJae Park if (!scheme->wmarks.activated) 1109ee801b7dSSeongJae Park pr_debug("activate a scheme (%d)\n", scheme->action); 1110ee801b7dSSeongJae Park scheme->wmarks.activated = true; 1111ee801b7dSSeongJae Park return 0; 1112ee801b7dSSeongJae Park } 1113ee801b7dSSeongJae Park 1114ee801b7dSSeongJae Park static void kdamond_usleep(unsigned long usecs) 1115ee801b7dSSeongJae Park { 11164de46a30SSeongJae Park /* See Documentation/timers/timers-howto.rst for the thresholds */ 11174de46a30SSeongJae Park if (usecs > 20 * USEC_PER_MSEC) 111870e92748SSeongJae Park schedule_timeout_idle(usecs_to_jiffies(usecs)); 1119ee801b7dSSeongJae Park else 112070e92748SSeongJae Park usleep_idle_range(usecs, usecs + 1); 1121ee801b7dSSeongJae Park } 1122ee801b7dSSeongJae Park 1123ee801b7dSSeongJae Park /* Returns negative error code if it's not activated but should return */ 1124ee801b7dSSeongJae Park static int kdamond_wait_activation(struct damon_ctx *ctx) 1125ee801b7dSSeongJae Park { 1126ee801b7dSSeongJae Park struct damos *s; 1127ee801b7dSSeongJae Park unsigned long wait_time; 1128ee801b7dSSeongJae Park unsigned long min_wait_time = 0; 112978049e94SJonghyeon Kim bool init_wait_time = false; 1130ee801b7dSSeongJae Park 1131ee801b7dSSeongJae Park while (!kdamond_need_stop(ctx)) { 1132ee801b7dSSeongJae Park damon_for_each_scheme(s, ctx) { 1133ee801b7dSSeongJae Park wait_time = damos_wmark_wait_us(s); 113478049e94SJonghyeon Kim if (!init_wait_time || wait_time < min_wait_time) { 113578049e94SJonghyeon Kim init_wait_time = true; 1136ee801b7dSSeongJae Park min_wait_time = wait_time; 1137ee801b7dSSeongJae Park } 113878049e94SJonghyeon Kim } 1139ee801b7dSSeongJae Park if (!min_wait_time) 1140ee801b7dSSeongJae Park return 0; 1141ee801b7dSSeongJae Park 1142ee801b7dSSeongJae Park kdamond_usleep(min_wait_time); 11436e74d2bfSSeongJae Park 11446e74d2bfSSeongJae Park if (ctx->callback.after_wmarks_check && 11456e74d2bfSSeongJae Park ctx->callback.after_wmarks_check(ctx)) 11466e74d2bfSSeongJae Park break; 1147ee801b7dSSeongJae Park } 1148ee801b7dSSeongJae Park return -EBUSY; 1149ee801b7dSSeongJae Park } 1150ee801b7dSSeongJae Park 11512224d848SSeongJae Park /* 11522224d848SSeongJae Park * The monitoring daemon that runs as a kernel thread 11532224d848SSeongJae Park */ 11542224d848SSeongJae Park static int kdamond_fn(void *data) 11552224d848SSeongJae Park { 1156cef4493fSYu Zhe struct damon_ctx *ctx = data; 1157f23b8eeeSSeongJae Park struct damon_target *t; 1158f23b8eeeSSeongJae Park struct damon_region *r, *next; 1159b9a6ac4eSSeongJae Park unsigned int max_nr_accesses = 0; 1160b9a6ac4eSSeongJae Park unsigned long sz_limit = 0; 11610f91d133SChangbin Du bool done = false; 11622224d848SSeongJae Park 116342e4cef5SChangbin Du pr_debug("kdamond (%d) starts\n", current->pid); 11642224d848SSeongJae Park 1165f7d911c3SSeongJae Park if (ctx->ops.init) 1166f7d911c3SSeongJae Park ctx->ops.init(ctx); 11672224d848SSeongJae Park if (ctx->callback.before_start && ctx->callback.before_start(ctx)) 11680f91d133SChangbin Du done = true; 11692224d848SSeongJae Park 1170b9a6ac4eSSeongJae Park sz_limit = damon_region_sz_limit(ctx); 1171b9a6ac4eSSeongJae Park 11720f91d133SChangbin Du while (!kdamond_need_stop(ctx) && !done) { 11736e74d2bfSSeongJae Park if (kdamond_wait_activation(ctx)) { 11746e74d2bfSSeongJae Park done = true; 1175ee801b7dSSeongJae Park continue; 11766e74d2bfSSeongJae Park } 1177ee801b7dSSeongJae Park 1178f7d911c3SSeongJae Park if (ctx->ops.prepare_access_checks) 1179f7d911c3SSeongJae Park ctx->ops.prepare_access_checks(ctx); 11802224d848SSeongJae Park if (ctx->callback.after_sampling && 1181abacd635SSeongJae Park ctx->callback.after_sampling(ctx)) { 11820f91d133SChangbin Du done = true; 1183abacd635SSeongJae Park continue; 1184abacd635SSeongJae Park } 11852224d848SSeongJae Park 118670e92748SSeongJae Park kdamond_usleep(ctx->sample_interval); 11872224d848SSeongJae Park 1188f7d911c3SSeongJae Park if (ctx->ops.check_accesses) 1189f7d911c3SSeongJae Park max_nr_accesses = ctx->ops.check_accesses(ctx); 11902224d848SSeongJae Park 11912224d848SSeongJae Park if (kdamond_aggregate_interval_passed(ctx)) { 1192b9a6ac4eSSeongJae Park kdamond_merge_regions(ctx, 1193b9a6ac4eSSeongJae Park max_nr_accesses / 10, 1194b9a6ac4eSSeongJae Park sz_limit); 11952224d848SSeongJae Park if (ctx->callback.after_aggregation && 1196abacd635SSeongJae Park ctx->callback.after_aggregation(ctx)) { 11970f91d133SChangbin Du done = true; 1198abacd635SSeongJae Park continue; 1199abacd635SSeongJae Park } 12001f366e42SSeongJae Park kdamond_apply_schemes(ctx); 1201f23b8eeeSSeongJae Park kdamond_reset_aggregated(ctx); 1202b9a6ac4eSSeongJae Park kdamond_split_regions(ctx); 1203f7d911c3SSeongJae Park if (ctx->ops.reset_aggregated) 1204f7d911c3SSeongJae Park ctx->ops.reset_aggregated(ctx); 12052224d848SSeongJae Park } 12062224d848SSeongJae Park 1207f7d911c3SSeongJae Park if (kdamond_need_update_operations(ctx)) { 1208f7d911c3SSeongJae Park if (ctx->ops.update) 1209f7d911c3SSeongJae Park ctx->ops.update(ctx); 1210b9a6ac4eSSeongJae Park sz_limit = damon_region_sz_limit(ctx); 12112224d848SSeongJae Park } 12122224d848SSeongJae Park } 1213f23b8eeeSSeongJae Park damon_for_each_target(t, ctx) { 1214f23b8eeeSSeongJae Park damon_for_each_region_safe(r, next, t) 1215b9a6ac4eSSeongJae Park damon_destroy_region(r, t); 1216f23b8eeeSSeongJae Park } 12172224d848SSeongJae Park 12180f91d133SChangbin Du if (ctx->callback.before_terminate) 12190f91d133SChangbin Du ctx->callback.before_terminate(ctx); 1220f7d911c3SSeongJae Park if (ctx->ops.cleanup) 1221f7d911c3SSeongJae Park ctx->ops.cleanup(ctx); 12222224d848SSeongJae Park 122342e4cef5SChangbin Du pr_debug("kdamond (%d) finishes\n", current->pid); 12242224d848SSeongJae Park mutex_lock(&ctx->kdamond_lock); 12252224d848SSeongJae Park ctx->kdamond = NULL; 12262224d848SSeongJae Park mutex_unlock(&ctx->kdamond_lock); 12272224d848SSeongJae Park 12282224d848SSeongJae Park mutex_lock(&damon_lock); 12292224d848SSeongJae Park nr_running_ctxs--; 12308b9b0d33SSeongJae Park if (!nr_running_ctxs && running_exclusive_ctxs) 12318b9b0d33SSeongJae Park running_exclusive_ctxs = false; 12322224d848SSeongJae Park mutex_unlock(&damon_lock); 12332224d848SSeongJae Park 12345f7fe2b9SChangbin Du return 0; 12352224d848SSeongJae Park } 123617ccae8bSSeongJae Park 12370d83b2d8SXin Hao /* 12380d83b2d8SXin Hao * struct damon_system_ram_region - System RAM resource address region of 12390d83b2d8SXin Hao * [@start, @end). 12400d83b2d8SXin Hao * @start: Start address of the region (inclusive). 12410d83b2d8SXin Hao * @end: End address of the region (exclusive). 12420d83b2d8SXin Hao */ 12430d83b2d8SXin Hao struct damon_system_ram_region { 12440d83b2d8SXin Hao unsigned long start; 12450d83b2d8SXin Hao unsigned long end; 12460d83b2d8SXin Hao }; 12470d83b2d8SXin Hao 12480d83b2d8SXin Hao static int walk_system_ram(struct resource *res, void *arg) 12490d83b2d8SXin Hao { 12500d83b2d8SXin Hao struct damon_system_ram_region *a = arg; 12510d83b2d8SXin Hao 12520d83b2d8SXin Hao if (a->end - a->start < resource_size(res)) { 12530d83b2d8SXin Hao a->start = res->start; 12540d83b2d8SXin Hao a->end = res->end; 12550d83b2d8SXin Hao } 12560d83b2d8SXin Hao return 0; 12570d83b2d8SXin Hao } 12580d83b2d8SXin Hao 12590d83b2d8SXin Hao /* 12600d83b2d8SXin Hao * Find biggest 'System RAM' resource and store its start and end address in 12610d83b2d8SXin Hao * @start and @end, respectively. If no System RAM is found, returns false. 12620d83b2d8SXin Hao */ 12630d83b2d8SXin Hao bool damon_find_biggest_system_ram(unsigned long *start, unsigned long *end) 12640d83b2d8SXin Hao 12650d83b2d8SXin Hao { 12660d83b2d8SXin Hao struct damon_system_ram_region arg = {}; 12670d83b2d8SXin Hao 12680d83b2d8SXin Hao walk_system_ram_res(0, ULONG_MAX, &arg, walk_system_ram); 12690d83b2d8SXin Hao if (arg.end <= arg.start) 12700d83b2d8SXin Hao return false; 12710d83b2d8SXin Hao 12720d83b2d8SXin Hao *start = arg.start; 12730d83b2d8SXin Hao *end = arg.end; 12740d83b2d8SXin Hao return true; 12750d83b2d8SXin Hao } 12760d83b2d8SXin Hao 1277a1870944SDawei Li static int __init damon_init(void) 1278a1870944SDawei Li { 1279a1870944SDawei Li damon_region_cache = KMEM_CACHE(damon_region, 0); 1280a1870944SDawei Li if (unlikely(!damon_region_cache)) { 1281a1870944SDawei Li pr_err("creating damon_region_cache fails\n"); 1282a1870944SDawei Li return -ENOMEM; 1283a1870944SDawei Li } 1284a1870944SDawei Li 1285a1870944SDawei Li return 0; 1286a1870944SDawei Li } 1287a1870944SDawei Li 1288a1870944SDawei Li subsys_initcall(damon_init); 1289a1870944SDawei Li 129017ccae8bSSeongJae Park #include "core-test.h" 1291