Messages in this thread Patch in this message | | | Date | Sun, 22 Apr 2018 20:03:49 -0700 | From | Matthew Wilcox <> | Subject | Re: [PATCH] mm: shmem: enable thp migration (Re: [PATCH v1] mm: consider non-anonymous thp as unmovable page) |
| |
On Fri, Apr 06, 2018 at 03:07:11AM +0000, Naoya Horiguchi wrote: > Subject: [PATCH] mm: enable thp migration for shmem thp
This patch is buggy, but not in a significant way:
> @@ -524,13 +524,26 @@ int migrate_page_move_mapping(struct address_space *mapping, > } > > radix_tree_replace_slot(&mapping->i_pages, pslot, newpage);
^^^ this line should have been deleted
> + if (PageTransHuge(page)) { > + int i; > + int index = page_index(page); > + > + for (i = 0; i < HPAGE_PMD_NR; i++) { ^^^ or this iteration should start at 1 > + pslot = radix_tree_lookup_slot(&mapping->i_pages, > + index + i); > + radix_tree_replace_slot(&mapping->i_pages, pslot, > + newpage + i); > + } > + } else { > + radix_tree_replace_slot(&mapping->i_pages, pslot, newpage); ^^^ and if the second option, then we don't need this line > + }
So either this:
- radix_tree_replace_slot(&mapping->i_pages, pslot, newpage); + if (PageTransHuge(page)) { + int i; + int index = page_index(page); + + for (i = 0; i < HPAGE_PMD_NR; i++) { + pslot = radix_tree_lookup_slot(&mapping->i_pages, + index + i); + radix_tree_replace_slot(&mapping->i_pages, pslot, + newpage + i); + } + } else { + radix_tree_replace_slot(&mapping->i_pages, pslot, newpage); + }
Or this:
radix_tree_replace_slot(&mapping->i_pages, pslot, newpage); + if (PageTransHuge(page)) { + int i; + int index = page_index(page); + + for (i = 1; i < HPAGE_PMD_NR; i++) { + pslot = radix_tree_lookup_slot(&mapping->i_pages, + index + i); + radix_tree_replace_slot(&mapping->i_pages, pslot, + newpage + i); + } + }
The second one is shorter and involves fewer lookups ...
| |