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#author("2025-09-11T20:06:59+09:00","default:guest","guest") #author("2025-09-11T20:07:46+09:00","default:guest","guest") *参照元 [#t2c8d114] #backlinks *説明 [#icb47ab4] -パス: [[linux-5.15/mm/vmscan.c]] -FIXME: これは何？ --説明 **引数 [#wc0275d0] --unsigned long nr_to_scan -- -struct lruvec *lruvec -- --[[linux-5.15/lruvec]] -struct scan_control *sc -- --[[linux-5.15/scan_control]] -enum lru_list lru -- --[[linux-5.15/lru_list]] **返り値 [#m721ffdf] -なし **参考 [#j42f1a41] *実装 [#bb73a88f] /* * shrink_active_list() moves pages from the active LRU to the inactive LRU. * * We move them the other way if the page is referenced by one or more * processes. * * If the pages are mostly unmapped, the processing is fast and it is * appropriate to hold lru_lock across the whole operation. But if * the pages are mapped, the processing is slow (page_referenced()), so * we should drop lru_lock around each page. It's impossible to balance * this, so instead we remove the pages from the LRU while processing them. * It is safe to rely on PG_active against the non-LRU pages in here because * nobody will play with that bit on a non-LRU page. * * The downside is that we have to touch page->_refcount against each page. * But we had to alter page->flags anyway. */ static void shrink_active_list(unsigned long nr_to_scan, struct lruvec *lruvec, struct scan_control *sc, enum lru_list lru) { unsigned long nr_taken; unsigned long nr_scanned; unsigned long vm_flags; LIST_HEAD(l_hold); /* The pages which were snipped off */ LIST_HEAD(l_active); LIST_HEAD(l_inactive); struct page *page; unsigned nr_deactivate, nr_activate; unsigned nr_rotated = 0; int file = is_file_lru(lru); struct pglist_data *pgdat = lruvec_pgdat(lruvec); lru_add_drain(); spin_lock_irq(&lruvec->lru_lock); - --[[linux-5.15/LIST_HEAD()]] --[[linux-5.15/page]] --[[linux-5.15/is_file_lru()]] --[[linux-5.15/pglist_data]] --[[linux-5.15/lruvec_pgdat()]] --[[linux-5.15/lru_add_drain()]] --[[linux-5.15/spin_lock_irq()]] nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &l_hold, &nr_scanned, sc, lru); __mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, nr_taken); - --[[linux-5.15/isolate_lru_pages()]] --[[linux-5.15/__mod_node_page_state()]] if (!cgroup_reclaim(sc)) __count_vm_events(PGREFILL, nr_scanned); __count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned); spin_unlock_irq(&lruvec->lru_lock); - --[[linux-5.15/cgroup_reclaim()]] --[[linux-5.15/__count_vm_events()]] --[[linux-5.15/lruvec_memcg()]] --[[linux-5.15/spin_unlock_irq()]] while (!list_empty(&l_hold)) { cond_resched(); page = lru_to_page(&l_hold); list_del(&page->lru); - --[[linux-5.15/list_empty()]] --[[linux-5.15/cond_resched()]] --[[linux-5.15/lru_to_page()]] --[[linux-5.15/list_del()]] if (unlikely(!page_evictable(page))) { putback_lru_page(page); continue; } - --[[linux-5.15/page_evictable()]] --[[linux-5.15/putback_lru_page()]] if (unlikely(buffer_heads_over_limit)) { if (page_has_private(page) && trylock_page(page)) { if (page_has_private(page)) try_to_release_page(page, 0); unlock_page(page); } } - --[[linux-5.15/page_has_private()]] --[[linux-5.15/trylock_page()]] --[[linux-5.15/try_to_release_page()]] --[[linux-5.15/unlock_page()]] if (page_referenced(page, 0, sc->target_mem_cgroup, &vm_flags)) { /* * Identify referenced, file-backed active pages and * give them one more trip around the active list. So * that executable code get better chances to stay in * memory under moderate memory pressure. Anon pages * are not likely to be evicted by use-once streaming * IO, plus JVM can create lots of anon VM_EXEC pages, * so we ignore them here. */ if ((vm_flags & VM_EXEC) && page_is_file_lru(page)) { nr_rotated += thp_nr_pages(page); list_add(&page->lru, &l_active); continue; } } - --[[linux-5.15/page_referenced()]] --[[linux-5.15/page_is_file_lru()]] --[[linux-5.15/thp_nr_pages()]] --[[linux-5.15/list_add()]] ClearPageActive(page); /* we are de-activating */ SetPageWorkingset(page); list_add(&page->lru, &l_inactive); } - --[[linux-5.15/ClearPageActive()]] --[[linux-5.15/SetPageWorkingset()]] --[[linux-5.15/list_add()]] /* * Move pages back to the lru list. */ spin_lock_irq(&lruvec->lru_lock); nr_activate = move_pages_to_lru(lruvec, &l_active); nr_deactivate = move_pages_to_lru(lruvec, &l_inactive); /* Keep all free pages in l_active list */ list_splice(&l_inactive, &l_active); - --[[linux-5.15/spin_lock_irq()]] --[[linux-5.15/move_pages_to_lru()]] --[[linux-5.15/list_splice()]] __count_vm_events(PGDEACTIVATE, nr_deactivate); __count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, nr_deactivate); - --[[linux-5.15/__count_vm_events()]] --[[linux-5.15/__count_memcg_events()]] --[[linux-5.15/lruvec_memcg()]] __mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken); spin_unlock_irq(&lruvec->lru_lock); - --[[linux-5.15/__mod_node_page_state()]] --[[linux-5.15/spin_unlock_irq()]] mem_cgroup_uncharge_list(&l_active); free_unref_page_list(&l_active); trace_mm_vmscan_lru_shrink_active(pgdat->node_id, nr_taken, nr_activate, nr_deactivate, nr_rotated, sc->priority, file); } - --[[linux-5.15/mem_cgroup_uncharge_list()]] --[[linux-5.15/free_unref_page_list()]] --[[linux-5.15/trace_mm_vmscan_lru_shrink_active()]] *コメント [#rd6ee5f5]
