Hi Naoya Horiguchi,
Thanks for reviewing.
On 2017/2/6 11:29, Naoya Horiguchi wrote:
> On Fri, Feb 03, 2017 at 03:59:30PM +0800, Yisheng Xie wrote:
>> We had considered all of the non-lru pages as unmovable before commit
>> bda807d44454 ("mm: migrate: support non-lru movable page migration"). But
>> now some of non-lru pages like zsmalloc, virtio-balloon pages also become
>> movable. So we can offline such blocks by using non-lru page migration.
>>
>> This patch straightforwardly adds non-lru migration code, which means
>> adding non-lru related code to the functions which scan over pfn and
>> collect pages to be migrated and isolate them before migration.
>>
>> Signed-off-by: Yisheng Xie <[email protected]>
>> Cc: Michal Hocko <[email protected]>
>> Cc: Minchan Kim <[email protected]>
>> Cc: Naoya Horiguchi <[email protected]>
>> Cc: Vlastimil Babka <[email protected]>
>> Cc: Andi Kleen <[email protected]>
>> Cc: Hanjun Guo <[email protected]>
>> Cc: Johannes Weiner <[email protected]>
>> Cc: Joonsoo Kim <[email protected]>
>> Cc: Mel Gorman <[email protected]>
>> Cc: Reza Arbab <[email protected]>
>> Cc: Taku Izumi <[email protected]>
>> Cc: Vitaly Kuznetsov <[email protected]>
>> Cc: Xishi Qiu <[email protected]>
>> ---
>> mm/memory_hotplug.c | 28 +++++++++++++++++-----------
>> mm/page_alloc.c | 8 ++++++--
>> 2 files changed, 23 insertions(+), 13 deletions(-)
>>
>> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
>> index ca2723d..ea1be08 100644
>> --- a/mm/memory_hotplug.c
>> +++ b/mm/memory_hotplug.c
>> @@ -1516,10 +1516,10 @@ int test_pages_in_a_zone(unsigned long start_pfn,
>> unsigned long end_pfn)
>> }
>>
>> /*
>> - * Scan pfn range [start,end) to find movable/migratable pages (LRU pages
>> - * and hugepages). We scan pfn because it's much easier than scanning over
>> - * linked list. This function returns the pfn of the first found movable
>> - * page if it's found, otherwise 0.
>> + * Scan pfn range [start,end) to find movable/migratable pages (LRU pages,
>> + * non-lru movable pages and hugepages). We scan pfn because it's much
>> + * easier than scanning over linked list. This function returns the pfn
>> + * of the first found movable page if it's found, otherwise 0.
>> */
>> static unsigned long scan_movable_pages(unsigned long start, unsigned long
>> end)
>> {
>> @@ -1530,6 +1530,8 @@ static unsigned long scan_movable_pages(unsigned long
>> start, unsigned long end)
>> page = pfn_to_page(pfn);
>> if (PageLRU(page))
>> return pfn;
>> + if (__PageMovable(page))
>> + return pfn;
>> if (PageHuge(page)) {
>> if (page_huge_active(page))
>> return pfn;
>> @@ -1606,21 +1608,25 @@ static struct page *new_node_page(struct page *page,
>> unsigned long private,
>> if (!get_page_unless_zero(page))
>> continue;
>> /*
>> - * We can skip free pages. And we can only deal with pages on
>> - * LRU.
>> + * We can skip free pages. And we can deal with pages on
>> + * LRU and non-lru movable pages.
>> */
>> - ret = isolate_lru_page(page);
>> + if (PageLRU(page))
>> + ret = isolate_lru_page(page);
>> + else
>> + ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE);
>> if (!ret) { /* Success */
>> put_page(page);
>> list_add_tail(&page->lru, &source);
>> move_pages--;
>> - inc_node_page_state(page, NR_ISOLATED_ANON +
>> - page_is_file_cache(page));
>> + if (!__PageMovable(page))
>
> If this check is identical with "if (PageLRU(page))" in this context,
> PageLRU(page) looks better because you already add same "if" above.
>
After isolated lru page, the PageLRU will be cleared, so use !__PageMovable
instead here for LRU page's mapping cannot have PAGE_MAPPING_MOVABLE.
I have add the comment in PATCH[3/4] HWPOISON: soft offlining for non-lru
movable page, so I do not add the same comment here.
Thanks
Yisheng Xie
> Otherwise, looks good to me.
>
> Thanks,
> Naoya Horiguchi
> .
>
