On 7/7/20 1:48 PM, Michal Hocko wrote:
> On Tue 07-07-20 16:44:48, Joonsoo Kim wrote:
>> From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
>>
>> There is a well-defined standard migration target callback. Use it
>> directly.
>>
>> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
>> ---
>> mm/memory-failure.c | 18 ++++++------------
>> 1 file changed, 6 insertions(+), 12 deletions(-)
>>
>> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
>> index 609d42b6..3b89804 100644
>> --- a/mm/memory-failure.c
>> +++ b/mm/memory-failure.c
>> @@ -1677,16 +1677,6 @@ int unpoison_memory(unsigned long pfn)
>> }
>> EXPORT_SYMBOL(unpoison_memory);
>>
>> -static struct page *new_page(struct page *p, unsigned long private)
>> -{
>> - struct migration_target_control mtc = {
>> - .nid = page_to_nid(p),
>> - .gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
>> - };
>> -
>> - return alloc_migration_target(p, (unsigned long)&mtc);
>> -}
>> -
>> /*
>> * Safely get reference count of an arbitrary page.
>> * Returns 0 for a free page, -EIO for a zero refcount page
>> @@ -1793,6 +1783,10 @@ static int __soft_offline_page(struct page *page)
>> const char *msg_page[] = {"page", "hugepage"};
>> bool huge = PageHuge(page);
>> LIST_HEAD(pagelist);
>> + struct migration_target_control mtc = {
>> + .nid = NUMA_NO_NODE,
>> + .gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
>> + };
>
> Is NUMA_NO_NODE really intended here? The original code has preferred to
> stay on the same node.
The alloc_migration_target() interprets NUMA_NO_NODE as a request to call
page_to_nid(), so we don't need these thin wrappers that do just that. I have
suggested this in v3 review and it's mentioned in 06/11.
> If this is intentional then the changelog should
> be explicit about that.
>
>>
>> /*
>> * Check PageHWPoison again inside page lock because PageHWPoison
>> @@ -1829,8 +1823,8 @@ static int __soft_offline_page(struct page *page)
>> }
>>
>> if (isolate_page(hpage, &pagelist)) {
>> - ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
>> - MIGRATE_SYNC, MR_MEMORY_FAILURE);
>> + ret = migrate_pages(&pagelist, alloc_migration_target, NULL,
>> + (unsigned long)&mtc, MIGRATE_SYNC, MR_MEMORY_FAILURE);
>> if (!ret) {
>> bool release = !huge;
>>
>> --
>> 2.7.4
>>
>
