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charset=us-ascii Content-Disposition: inline In-Reply-To: <20200422084815.21913-1-jaewon31.kim@samsung.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Apr 22, 2020 at 05:48:15PM +0900, Jaewon Kim wrote: > @@ -1295,11 +1295,15 @@ static unsigned long shrink_page_list(struct list_head *page_list, > */ > if (page_mapped(page)) { > enum ttu_flags flags = ttu_flags | TTU_BATCH_FLUSH; > + bool lazyfree = PageAnon(page) && !PageSwapBacked(page); > > if (unlikely(PageTransHuge(page))) > flags |= TTU_SPLIT_HUGE_PMD; > + > if (!try_to_unmap(page, flags)) { > stat->nr_unmap_fail += nr_pages; > + if (lazyfree && PageSwapBacked(page)) This looks pretty strange, until you remember that try_to_unmap() could SetPageSwapbacked again. This might be more obvious? was_swapbacked = PageSwapBacked(page); if (!try_to_unmap(page, flags)) { stat->nr_unmap_fail += nr_pages; if (!was_swapbacked && PageSwapBacked(page)) > + stat->nr_lazyfree_fail += nr_pages; > goto activate_locked; Or at least was_lazyfree. > @@ -1491,8 +1495,8 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, > .priority = DEF_PRIORITY, > .may_unmap = 1, > }; > - struct reclaim_stat dummy_stat; > - unsigned long ret; > + struct reclaim_stat stat; > + unsigned long reclaimed; nr_reclaimed would be better. I also prefer keeping dummy_stat, since that's still what it is.