Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 | // SPDX-License-Identifier: GPL-2.0 /* * Common Primitives for Data Access Monitoring * * Author: SeongJae Park <sj@kernel.org> */ #include <linux/mmu_notifier.h> #include <linux/page_idle.h> #include <linux/pagemap.h> #include <linux/rmap.h> #include "ops-common.h" /* * Get an online page for a pfn if it's in the LRU list. Otherwise, returns * NULL. * * The body of this function is stolen from the 'page_idle_get_folio()'. We * steal rather than reuse it because the code is quite simple. */ struct folio *damon_get_folio(unsigned long pfn) { struct page *page = pfn_to_online_page(pfn); struct folio *folio; if (!page || PageTail(page)) return NULL; folio = page_folio(page); if (!folio_test_lru(folio) || !folio_try_get(folio)) return NULL; if (unlikely(page_folio(page) != folio || !folio_test_lru(folio))) { folio_put(folio); folio = NULL; } return folio; } void damon_ptep_mkold(pte_t *pte, struct vm_area_struct *vma, unsigned long addr) { struct folio *folio = damon_get_folio(pte_pfn(ptep_get(pte))); if (!folio) return; if (ptep_clear_young_notify(vma, addr, pte)) folio_set_young(folio); folio_set_idle(folio); folio_put(folio); } void damon_pmdp_mkold(pmd_t *pmd, struct vm_area_struct *vma, unsigned long addr) { #ifdef CONFIG_TRANSPARENT_HUGEPAGE struct folio *folio = damon_get_folio(pmd_pfn(pmdp_get(pmd))); if (!folio) return; if (pmdp_clear_young_notify(vma, addr, pmd)) folio_set_young(folio); folio_set_idle(folio); folio_put(folio); #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ } #define DAMON_MAX_SUBSCORE (100) #define DAMON_MAX_AGE_IN_LOG (32) int damon_hot_score(struct damon_ctx *c, struct damon_region *r, struct damos *s) { int freq_subscore; unsigned int age_in_sec; int age_in_log, age_subscore; unsigned int freq_weight = s->quota.weight_nr_accesses; unsigned int age_weight = s->quota.weight_age; int hotness; freq_subscore = r->nr_accesses * DAMON_MAX_SUBSCORE / damon_max_nr_accesses(&c->attrs); age_in_sec = (unsigned long)r->age * c->attrs.aggr_interval / 1000000; for (age_in_log = 0; age_in_log < DAMON_MAX_AGE_IN_LOG && age_in_sec; age_in_log++, age_in_sec >>= 1) ; /* If frequency is 0, higher age means it's colder */ if (freq_subscore == 0) age_in_log *= -1; /* * Now age_in_log is in [-DAMON_MAX_AGE_IN_LOG, DAMON_MAX_AGE_IN_LOG]. * Scale it to be in [0, 100] and set it as age subscore. */ age_in_log += DAMON_MAX_AGE_IN_LOG; age_subscore = age_in_log * DAMON_MAX_SUBSCORE / DAMON_MAX_AGE_IN_LOG / 2; hotness = (freq_weight * freq_subscore + age_weight * age_subscore); if (freq_weight + age_weight) hotness /= freq_weight + age_weight; /* * Transform it to fit in [0, DAMOS_MAX_SCORE] */ hotness = hotness * DAMOS_MAX_SCORE / DAMON_MAX_SUBSCORE; return hotness; } int damon_cold_score(struct damon_ctx *c, struct damon_region *r, struct damos *s) { int hotness = damon_hot_score(c, r, s); /* Return coldness of the region */ return DAMOS_MAX_SCORE - hotness; } |