soft_offline_huge_page and __soft_offline_page share quite some code, and it can be re-joined into one single function without losing neither functionatilty nor readibility.
This allows us of getting rid of quite some duplicated code. Signed-off-by: Oscar Salvador <[email protected]> --- mm/memory-failure.c | 145 ++++++++++++++++++++-------------------------------- 1 file changed, 56 insertions(+), 89 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index d44dacb8e2ea..ce017a0d79a6 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1689,57 +1689,48 @@ static int get_any_page(struct page *page, unsigned long pfn) return ret; } -static int soft_offline_huge_page(struct page *page) +static bool isolate_page(struct page *page, struct list_head *pagelist) { - int ret; - unsigned long pfn = page_to_pfn(page); - struct page *hpage = compound_head(page); - LIST_HEAD(pagelist); + bool isolated = false; + bool lru = PageLRU(page); - /* - * This double-check of PageHWPoison is to avoid the race with - * memory_failure(). See also comment in __soft_offline_page(). - */ - lock_page(hpage); - if (PageHWPoison(hpage)) { - unlock_page(hpage); - put_hwpoison_page(hpage); - pr_info("soft offline: %#lx hugepage already poisoned\n", pfn); - return -EBUSY; + if (PageHuge(page)) { + isolated = isolate_huge_page(page, pagelist); + } else { + if (PageLRU(page)) + isolated = !isolate_lru_page(page); + else + isolated = !isolate_movable_page(page, ISOLATE_UNEVICTABLE); + + if (isolated) { + if (lru) + inc_node_page_state(page, NR_ISOLATED_ANON + + page_is_file_cache(page)); + list_add(&page->lru, pagelist); + } } - unlock_page(hpage); - ret = isolate_huge_page(hpage, &pagelist); /* - * get_any_page() and isolate_huge_page() takes a refcount each, - * so need to drop one here. + * If we succeed to isolate the page, we grabbed another refcount on + * the page, so we can safely drop the one we got from get_any_pages(). + * If we failed to isolate the page, it means that we cannot go further + * any further and we will return an error, so drop the reference we got + * from get_any_pages() as well. */ - put_hwpoison_page(hpage); - if (!ret) { - pr_info("soft offline: %#lx hugepage failed to isolate\n", pfn); - return -EBUSY; - } - - ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL, - MIGRATE_SYNC, MR_MEMORY_FAILURE); - if (!ret) { - if (!page_set_poison(page)) - ret = -EBUSY; - } else { - pr_info("soft offline: %#lx: hugepage migration failed %d, type %lx (%pGp)\n", - pfn, ret, page->flags, &page->flags); - if (!list_empty(&pagelist)) - putback_movable_pages(&pagelist); - if (ret > 0) - ret = -EIO; - } - return ret; + put_hwpoison_page(page); + return isolated; } - +/* + * This routine handles both hugetlb and normal pages + */ static int __soft_offline_page(struct page *page) { - int ret; + int ret = 0; unsigned long pfn = page_to_pfn(page); + struct page *hpage = compound_head(page); + const char *msg_page[] = { "page", "hugepage"}; + bool huge = PageHuge(page); + LIST_HEAD(pagelist); /* * Check PageHWPoison again inside page lock because PageHWPoison @@ -1747,92 +1738,68 @@ static int __soft_offline_page(struct page *page) * memory_failure() also double-checks PageHWPoison inside page lock, * so there's no race between soft_offline_page() and memory_failure(). */ - lock_page(page); - wait_on_page_writeback(page); - if (PageHWPoison(page)) { - unlock_page(page); - put_hwpoison_page(page); + lock_page(hpage); + if (!PageHuge(page)) + wait_on_page_writeback(page); + if (PageHWPoison(hpage)) { + unlock_page(hpage); + put_hwpoison_page(hpage); pr_info("soft offline: %#lx page already poisoned\n", pfn); return -EBUSY; } - /* - * Try to invalidate first. This should work for - * non dirty unmapped page cache pages. - */ - ret = invalidate_inode_page(page); + + if (!PageHuge(page)) + /* + * Try to invalidate first. This should work for + * non dirty unmapped page cache pages. + */ + ret = invalidate_inode_page(page); unlock_page(page); /* * RED-PEN would be better to keep it isolated here, but we * would need to fix isolation locking first. */ - if (ret == 1) { + if (ret) { pr_info("soft_offline: %#lx: invalidated\n", pfn); page_set_poison(page); return 0; } - /* - * Simple invalidation didn't work. - * Try to migrate to a new page instead. migrate.c - * handles a large number of cases for us. - */ - if (PageLRU(page)) - ret = isolate_lru_page(page); - else - ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE); - /* - * Drop page reference which is came from get_any_page() - * successful isolate_lru_page() already took another one. - */ - put_hwpoison_page(page); - if (!ret) { - LIST_HEAD(pagelist); - /* - * After isolated lru page, the PageLRU will be cleared, - * so use !__PageMovable instead for LRU page's mapping - * cannot have PAGE_MAPPING_MOVABLE. - */ - if (!__PageMovable(page)) - inc_node_page_state(page, NR_ISOLATED_ANON + - page_is_file_cache(page)); - list_add(&page->lru, &pagelist); + if (isolate_page(hpage, &pagelist)) { ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL, - MIGRATE_SYNC, MR_MEMORY_FAILURE); + MIGRATE_SYNC, MR_MEMORY_FAILURE); if (!ret) { /* * Page was succesfully migrated. */ - page_set_poison(page); + if (!page_set_poison(page)) + ret = -EBUSY; } else { if (!list_empty(&pagelist)) putback_movable_pages(&pagelist); - pr_info("soft offline: %#lx: migration failed %d, type %lx (%pGp)\n", - pfn, ret, page->flags, &page->flags); + pr_info("soft offline: %#lx: %s migration failed %d, type %lx (%pGp)\n", + pfn, msg_page[huge], ret, page->flags, &page->flags); if (ret > 0) ret = -EIO; } } else { - pr_info("soft offline: %#lx: isolation failed: %d, page count %d, type %lx (%pGp)\n", - pfn, ret, page_count(page), page->flags, &page->flags); + pr_info("soft offline: %#lx %s isolation failed: %d, page count %d, type %lx (%pGp)\n", + pfn, msg_page[huge], ret, page_count(page), page->flags, &page->flags); } + return ret; } static int soft_offline_in_use_page(struct page *page) { - int ret; struct page *hpage = compound_head(page); if (!PageHuge(page) && PageTransHuge(hpage)) if (try_to_split_thp_page(page, "soft offline") < 0) return -EBUSY; - if (PageHuge(page)) - ret = soft_offline_huge_page(page); - else - ret = __soft_offline_page(page); - return ret; + return __soft_offline_page(page); } static int soft_offline_free_page(struct page *page) -- 2.12.3
