On Sun, Mar 15, 2020 at 10:54:03AM +0200, Mika Penttil?? wrote: > > >On 15.3.2020 10.18, Wei Yang wrote: >> On Fri, Feb 28, 2020 at 11:38:18AM +0800, Huang, Ying wrote: >> > From: Huang Ying <ying.huang@xxxxxxxxx> >> > >> > Now !PageSwapBacked() is used as the flag for the pages freed lazily >> > via MADV_FREE. This isn't obvious enough. So Dave suggested to add a >> > new page flag for that to improve the code readability. >> I am confused with the usage of PageSwapBacked(). >> >> Previously I thought this flag means the page is swapin, set in >> swapin_readahead(). While I found page_add_new_anon_rmap() would set it too. >> This means every anon page would carry this flag. Then what is this flag >> means? >> >> > >But not all PageSwapBacked() pages are anon, like shmem. > Yes, while it looks shmem is the only exception. I am still struggling to understand the meaning of this flag. > >--Mika -- Wei Yang Help you, Help me
