On 1/22/21 11:05 PM, Yu Zhao wrote: > The "enum lru_list" parameter to add_page_to_lru_list() and > add_page_to_lru_list_tail() is redundant in the sense that it can > be extracted from the "struct page" parameter by page_lru(). Okay, however, it means repeated extraction of a value that we already knew. The result of compilation is rather sad. This is bloat-o-meter on mm/built-in.a (without CONFIG_DEBUG_VM, btw) between patch 2 and 5: add/remove: 0/0 grow/shrink: 10/5 up/down: 1837/-60 (1777) Function old new delta lru_deactivate_file_fn 932 1368 +436 lru_lazyfree_fn.part 629 953 +324 check_move_unevictable_pages 1171 1424 +253 __activate_page.part 735 984 +249 lru_deactivate_fn.part 593 822 +229 perf_trace_mm_lru_insertion 458 560 +102 trace_event_raw_event_mm_lru_insertion 412 500 +88 __page_cache_release 479 558 +79 release_pages 1430 1499 +69 pagevec_move_tail_fn.part 761 769 +8 isolate_lru_page 471 470 -1 __bpf_trace_mm_lru_insertion 7 5 -2 __traceiter_mm_lru_insertion 55 47 -8 isolate_migratepages_block 3200 3185 -15 __pagevec_lru_add_fn 1092 1058 -34 > A caveat is that we need to make sure PageActive() or > PageUnevictable() is correctly set or cleared before calling > these two functions. And they are indeed. > > Link: https://lore.kernel.org/linux-mm/20201207220949.830352-4-yuzhao@xxxxxxxxxx/ > Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx> > --- > include/linux/mm_inline.h | 8 ++++++-- > mm/swap.c | 15 +++++++-------- > mm/vmscan.c | 6 ++---- > 3 files changed, 15 insertions(+), 14 deletions(-) > > diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h > index 2889741f450a..130ba3201d3f 100644 > --- a/include/linux/mm_inline.h > +++ b/include/linux/mm_inline.h > @@ -106,15 +106,19 @@ static __always_inline enum lru_list page_lru(struct page *page) > } > > static __always_inline void add_page_to_lru_list(struct page *page, > - struct lruvec *lruvec, enum lru_list lru) > + struct lruvec *lruvec) > { > + enum lru_list lru = page_lru(page); > + > update_lru_size(lruvec, lru, page_zonenum(page), thp_nr_pages(page)); > list_add(&page->lru, &lruvec->lists[lru]); > } > > static __always_inline void add_page_to_lru_list_tail(struct page *page, > - struct lruvec *lruvec, enum lru_list lru) > + struct lruvec *lruvec) > { > + enum lru_list lru = page_lru(page); > + > update_lru_size(lruvec, lru, page_zonenum(page), thp_nr_pages(page)); > list_add_tail(&page->lru, &lruvec->lists[lru]); > } > diff --git a/mm/swap.c b/mm/swap.c > index 490553f3f9ef..4b058ef37add 100644 > --- a/mm/swap.c > +++ b/mm/swap.c > @@ -231,7 +231,7 @@ static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec) > if (!PageUnevictable(page)) { > del_page_from_lru_list(page, lruvec, page_lru(page)); > ClearPageActive(page); > - add_page_to_lru_list_tail(page, lruvec, page_lru(page)); > + add_page_to_lru_list_tail(page, lruvec); > __count_vm_events(PGROTATED, thp_nr_pages(page)); > } > } > @@ -313,8 +313,7 @@ static void __activate_page(struct page *page, struct lruvec *lruvec) > > del_page_from_lru_list(page, lruvec, lru); > SetPageActive(page); > - lru += LRU_ACTIVE; > - add_page_to_lru_list(page, lruvec, lru); > + add_page_to_lru_list(page, lruvec); > trace_mm_lru_activate(page); > > __count_vm_events(PGACTIVATE, nr_pages); > @@ -543,14 +542,14 @@ static void lru_deactivate_file_fn(struct page *page, struct lruvec *lruvec) > * It can make readahead confusing. But race window > * is _really_ small and it's non-critical problem. > */ > - add_page_to_lru_list(page, lruvec, lru); > + add_page_to_lru_list(page, lruvec); > SetPageReclaim(page); > } else { > /* > * The page's writeback ends up during pagevec > * We moves tha page into tail of inactive. > */ > - add_page_to_lru_list_tail(page, lruvec, lru); > + add_page_to_lru_list_tail(page, lruvec); > __count_vm_events(PGROTATED, nr_pages); > } > > @@ -570,7 +569,7 @@ static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec) > del_page_from_lru_list(page, lruvec, lru + LRU_ACTIVE); > ClearPageActive(page); > ClearPageReferenced(page); > - add_page_to_lru_list(page, lruvec, lru); > + add_page_to_lru_list(page, lruvec); > > __count_vm_events(PGDEACTIVATE, nr_pages); > __count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, > @@ -595,7 +594,7 @@ static void lru_lazyfree_fn(struct page *page, struct lruvec *lruvec) > * anonymous pages > */ > ClearPageSwapBacked(page); > - add_page_to_lru_list(page, lruvec, LRU_INACTIVE_FILE); > + add_page_to_lru_list(page, lruvec); > > __count_vm_events(PGLAZYFREE, nr_pages); > __count_memcg_events(lruvec_memcg(lruvec), PGLAZYFREE, > @@ -1005,7 +1004,7 @@ static void __pagevec_lru_add_fn(struct page *page, struct lruvec *lruvec) > __count_vm_events(UNEVICTABLE_PGCULLED, nr_pages); > } > > - add_page_to_lru_list(page, lruvec, lru); > + add_page_to_lru_list(page, lruvec); > trace_mm_lru_insertion(page, lru); > } > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 19875660e8f8..09e4f97488c9 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -1867,7 +1867,7 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec, > * inhibits memcg migration). > */ > VM_BUG_ON_PAGE(!lruvec_holds_page_lru_lock(page, lruvec), page); > - add_page_to_lru_list(page, lruvec, page_lru(page)); > + add_page_to_lru_list(page, lruvec); > nr_pages = thp_nr_pages(page); > nr_moved += nr_pages; > if (PageActive(page)) > @@ -4282,12 +4282,10 @@ void check_move_unevictable_pages(struct pagevec *pvec) > > lruvec = relock_page_lruvec_irq(page, lruvec); > if (page_evictable(page) && PageUnevictable(page)) { > - enum lru_list lru = page_lru_base_type(page); > - > VM_BUG_ON_PAGE(PageActive(page), page); > ClearPageUnevictable(page); > del_page_from_lru_list(page, lruvec, LRU_UNEVICTABLE); > - add_page_to_lru_list(page, lruvec, lru); > + add_page_to_lru_list(page, lruvec); > pgrescued += nr_pages; > } > SetPageLRU(page); >
