On Thu, Sep 14, 2023 at 9:33 PM 江志国 <justinjiang@xxxxxxxx> wrote: > > Hi Yu Zhao: > > Thank you for your reply and sharing. Sorry, wrong link. This is the right one: https://www.kernel.org/doc/html/latest/mm/unevictable-lru.html#the-unevictable-lru-folio-list > On Thu, Sep 14, 2023 at 9:19 PM 江志国 <justinjiang@xxxxxxxx> wrote: > > > > Hi Yu Zhao: > > > > How is the unevictable folio managed in kernel? > > https://www.kernel.org/doc/Documentation/vm/unevictable-lru.txt > > > On Thu, Sep 14, 2023 at 8:08 AM Zhiguo Jiang <justinjiang@xxxxxxxx> wrote: > > > > > > The unevictable folio is not supported to add to lruvec->lists in > > > lruvec_add_folio(). > > > > > > So use lruvec_add_folio_tail() instead of lruvec_add_folio() to add > > > unevictable folio to lruvec->lists in sort_folio(). > > > > > > Signed-off-by: Zhiguo Jiang <justinjiang@xxxxxxxx> > > > --- > > > mm/vmscan.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) mode change 100644 > > > => > > > 100755 mm/vmscan.c > > > > > > diff --git a/mm/vmscan.c b/mm/vmscan.c index > > > 661615fa709b..a15e45632034 > > > --- a/mm/vmscan.c > > > +++ b/mm/vmscan.c > > > @@ -4237,7 +4237,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, struct scan_c > > > success = lru_gen_del_folio(lruvec, folio, true); > > > VM_WARN_ON_ONCE_FOLIO(!success, folio); > > > folio_set_unevictable(folio); > > > - lruvec_add_folio(lruvec, folio); > > > + lruvec_add_folio_tail(lruvec, folio); > > > __count_vm_events(UNEVICTABLE_PGCULLED, delta); > > > return true; > > > } > > > > NAK. > > > > lruvec_add_folio() > > { > > ... > > > > if (lru != LRU_UNEVICTABLE) > > list_add(&folio->lru, &lruvec->lists[lru]); } > > > > lruvec_add_folio_tail() > > { > > ... > > > > /* This is not expected to be used on LRU_UNEVICTABLE */ > > list_add_tail(&folio->lru, &lruvec->lists[lru]); } > > > > struct page { > > ... > > union { > > struct list_head lru; > > > > /* Or, for the Unevictable "LRU list" slot */ > > struct { > > ... > > }
