From 5649d113ffce9f532a9ecc5ab96a93e02efbf283 Mon Sep 17 00:00:00 2001 From: Yang Yang Date: Wed, 18 Jan 2023 20:13:03 +0800 Subject: [PATCH] swap_state: update shadow_nodes for anonymous page Shadow_nodes is for shadow nodes reclaiming of workingset handling, it is updated when page cache add or delete since long time ago workingset only supported page cache. But when workingset supports anonymous page detection, we missied updating shadow nodes for it. This caused that shadow nodes of anonymous page will never be reclaimd by scan_shadow_nodes() even they use much memory and system memory is tense. So update shadow_nodes of anonymous page when swap cache is add or delete by calling xas_set_update(..workingset_update_node). Link: https://lkml.kernel.org/r/202301182013032211005@zte.com.cn Fixes: aae466b0052e ("mm/swap: implement workingset detection for anonymous LRU") Signed-off-by: Yang Yang Reviewed-by: Ran Xiaokai Cc: Bagas Sanjaya Cc: Johannes Weiner Cc: Joonsoo Kim Cc: Matthew Wilcox Signed-off-by: Andrew Morton --- include/linux/xarray.h | 3 ++- mm/swap_state.c | 6 ++++++ mm/workingset.c | 21 +++++++++++++-------- 3 files changed, 21 insertions(+), 9 deletions(-) diff --git a/include/linux/xarray.h b/include/linux/xarray.h index 44dd6d6..741703b 100644 --- a/include/linux/xarray.h +++ b/include/linux/xarray.h @@ -1643,7 +1643,8 @@ static inline void xas_set_order(struct xa_state *xas, unsigned long index, * @update: Function to call when updating a node. * * The XArray can notify a caller after it has updated an xa_node. - * This is advanced functionality and is only needed by the page cache. + * This is advanced functionality and is only needed by the page + * cache and swap cache. */ static inline void xas_set_update(struct xa_state *xas, xa_update_node_t update) { diff --git a/mm/swap_state.c b/mm/swap_state.c index cb9aaa0..7a003d8 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -94,6 +94,8 @@ int add_to_swap_cache(struct folio *folio, swp_entry_t entry, unsigned long i, nr = folio_nr_pages(folio); void *old; + xas_set_update(&xas, workingset_update_node); + VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); VM_BUG_ON_FOLIO(folio_test_swapcache(folio), folio); VM_BUG_ON_FOLIO(!folio_test_swapbacked(folio), folio); @@ -145,6 +147,8 @@ void __delete_from_swap_cache(struct folio *folio, pgoff_t idx = swp_offset(entry); XA_STATE(xas, &address_space->i_pages, idx); + xas_set_update(&xas, workingset_update_node); + VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); VM_BUG_ON_FOLIO(!folio_test_swapcache(folio), folio); VM_BUG_ON_FOLIO(folio_test_writeback(folio), folio); @@ -252,6 +256,8 @@ void clear_shadow_from_swap_cache(int type, unsigned long begin, struct address_space *address_space = swap_address_space(entry); XA_STATE(xas, &address_space->i_pages, curr); + xas_set_update(&xas, workingset_update_node); + xa_lock_irq(&address_space->i_pages); xas_for_each(&xas, old, end) { if (!xa_is_value(old)) diff --git a/mm/workingset.c b/mm/workingset.c index f194d13b..00c6f4d 100644 --- a/mm/workingset.c +++ b/mm/workingset.c @@ -657,11 +657,14 @@ static enum lru_status shadow_lru_isolate(struct list_head *item, goto out; } - if (!spin_trylock(&mapping->host->i_lock)) { - xa_unlock(&mapping->i_pages); - spin_unlock_irq(lru_lock); - ret = LRU_RETRY; - goto out; + /* For page cache we need to hold i_lock */ + if (mapping->host != NULL) { + if (!spin_trylock(&mapping->host->i_lock)) { + xa_unlock(&mapping->i_pages); + spin_unlock_irq(lru_lock); + ret = LRU_RETRY; + goto out; + } } list_lru_isolate(lru, item); @@ -683,9 +686,11 @@ static enum lru_status shadow_lru_isolate(struct list_head *item, out_invalid: xa_unlock_irq(&mapping->i_pages); - if (mapping_shrinkable(mapping)) - inode_add_lru(mapping->host); - spin_unlock(&mapping->host->i_lock); + if (mapping->host != NULL) { + if (mapping_shrinkable(mapping)) + inode_add_lru(mapping->host); + spin_unlock(&mapping->host->i_lock); + } ret = LRU_REMOVED_RETRY; out: cond_resched(); -- 2.7.4