lkml.org 
[lkml]   [2021]   [Jan]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v2 03/10] mm: don't pass "enum lru_list" to lru list addition functions
    On Tue, Jan 26, 2021 at 08:13:11PM +0100, Vlastimil Babka wrote:
    > 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:

    Thanks for noticing this, Vlastimil. Should I drop the rest of the
    series except the first patch?

    > 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@google.com/
    > > Signed-off-by: Yu Zhao <yuzhao@google.com>
    > > ---
    > > 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);
    > >
    >

    \
     
     \ /
      Last update: 2021-01-27 06:37    [W:4.529 / U:0.088 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site