diff options
| -rw-r--r-- | mm/swap.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/mm/swap.c b/mm/swap.c index 77825883298f..f76c76c7501b 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -446,13 +446,22 @@ void mark_page_accessed(struct page *page) } EXPORT_SYMBOL(mark_page_accessed); +/* + * Order of operations is important: flush the pagevec when it's already + * full, not when adding the last page, to make sure that last page is + * not added to the LRU directly when passed to this function. Because + * mark_page_accessed() (called after this when writing) only activates + * pages that are on the LRU, linear writes in subpage chunks would see + * every PAGEVEC_SIZE page activated, which is unexpected. + */ void __lru_cache_add(struct page *page, enum lru_list lru) { struct pagevec *pvec = &get_cpu_var(lru_add_pvecs)[lru]; page_cache_get(page); - if (!pagevec_add(pvec, page)) + if (!pagevec_space(pvec)) __pagevec_lru_add(pvec, lru); + pagevec_add(pvec, page); put_cpu_var(lru_add_pvecs); } EXPORT_SYMBOL(__lru_cache_add); |