On 2023/8/3 20:30, Matthew Wilcox wrote:
On Thu, Aug 03, 2023 at 03:13:21PM +0800, Kefeng Wang wrote:
On 2023/8/2 20:21, Matthew Wilcox wrote:
On Wed, Aug 02, 2023 at 05:53:43PM +0800, Kefeng Wang wrote:
err = -EACCES;
- if (page_mapcount(page) > 1 && !migrate_all)
- goto out_putpage;
+ if (folio_estimated_sharers(folio) > 1 && !migrate_all)
+ goto out_putfolio;
I do not think this is the correct change. Maybe leave this line
alone.
Ok, I am aware of the discussion about this in other mail, will not
change it(also the next two patch about this function), or wait the
new work of David.
- if (PageHuge(page)) {
- if (PageHead(page)) {
- isolated = isolate_hugetlb(page_folio(page), pagelist);
+ if (folio_test_hugetlb(folio)) {
+ if (folio_test_large(folio)) {
This makes no sense when you read it. All hugetlb folios are large,
by definition. Think about what this code used to do, and what it
should be changed to.
hugetlb folio is self large folio, will drop redundant check
No, that's not the difference. Keep thinking about it. This is not
a mechanical translation!
if (PageHuge(page)) // page must be a hugetlb page
if (PageHead(page)) // page must be a head page, not tail
isolate_hugetlb() // isolate the hugetlb page if head
After using folio,
if (folio_test_hugetlb(folio)) // only check folio is hugetlb or not
I don't check the page is head or not, since the follow_page could
return a sub-page, so the check PageHead need be retained, right?
