On Mon, Oct 30, 2023 at 11:22:18PM +0000, Matthew Wilcox wrote: > On Mon, Oct 30, 2023 at 02:00:05PM -0400, Gregory Price wrote: > > kpageflags reads page-flags directly from the page, even when the > > respective flag is only updated on the headpage of a folio. > > > > Update bitchecks to use PAGEFLAG() interfaces to check folio for the > > referenced, dirty, lru, active, and unevictable bits. > > But uptodate, writeback and reclaim (amongst others) are also defined > only on the head page. > Ah yes i was only looking at the things defined w/ PAGEFLAG defines in page-flags.h. I'll give it full once over can collect them all, my bad. (also i forgot to update my commit message) Quick question here since i have your attention: any recommendation on what to do for ONLY_HEAD flags? If the provided page is not the head, should the flag report 0... or whatever the head says? > > u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate); > > u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback); > > > > u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim); > > > > if (PageSwapCache(page)) > > u |= 1 << KPF_SWAPCACHE; > > u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked); > > > > u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked); >
