Messages in this thread | | | Date | Fri, 2 Sep 2022 10:42:48 +0200 | From | David Hildenbrand <> | Subject | Re: [PATCH 2/2] mm: add pageblock_aligned() macro |
| |
On 02.09.22 08:47, Kefeng Wang wrote: > Add pageblock_aligned() and use it to simplify code. > > Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> > ---
[...]
> - unsigned long nr_pgmask = pageblock_nr_pages - 1; > int nid = zone_to_nid(zone); > unsigned long nr_pages = 0; > int zid = zone_idx(zone); > @@ -1977,7 +1974,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone, > if (!deferred_pfn_valid(pfn)) { > page = NULL; > continue; > - } else if (!page || !(pfn & nr_pgmask)) {
I didn't sleep too well this night and am tired, please tell me why I'm wrong :)
"pfn & (pageblock_nr_pages - 1)" is true if the pageblock is not aligned
E.g., pfn = 1, pageblock_nr_pages = 512
pfn & (pageblock_nr_pages - 1) -> 1 & (512 - 1) -> 1 & 511 -> true
"!(pfn & (pageblock_nr_pages - 1))" is true if the pageblock is aligned -> !(true) -> false
However, "!pageblock_aligned(1)" = true
> + } else if (!page || !pageblock_aligned(pfn)) {
So shouldn't this be "pageblock_aligned(pfn)"
?
> page = pfn_to_page(pfn); > } else { > page++;
-- Thanks,
David / dhildenb
| |