Re: [Patch v3] mm/page_alloc.c: use NODE_MASK_NONE define used_mask

From: David Hildenbrand
Date: Mon Mar 30 2020 - 11:01:44 EST


On 29.03.20 06:00, John Hubbard wrote:
> On 3/28/20 7:42 PM, Wei Yang wrote:
>> For all 0 nodemask_t, we have already define macro NODE_MASK_NONE.
>> Leverage this to define an all clear nodemask.
>
> It would be a little clearer if you used wording more like this:
>
> Subject: [Patch v3] mm/page_alloc.c: use NODE_MASK_NONE in build_zonelists()
>
> Slightly simplify the code by initializing user_mask with
> NODE_MASK_NONE, instead of later calling nodes_clear(). This saves
> a line of code.
>
>
>>
>> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
>>
>> ---
>> v3: adjust the commit log a little
>> v2: use NODE_MASK_NONE as suggested by David Hildenbrand
>> ---
>> mm/page_alloc.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
>> index ef790dfad6aa..dfcf2682ed40 100644
>> --- a/mm/page_alloc.c
>> +++ b/mm/page_alloc.c
>> @@ -5587,14 +5587,13 @@ static void build_zonelists(pg_data_t *pgdat)
>> {
>> static int node_order[MAX_NUMNODES];
>> int node, load, nr_nodes = 0;
>> - nodemask_t used_mask;
>> + nodemask_t used_mask = NODE_MASK_NONE;
>> int local_node, prev_node;
>>
>> /* NUMA-aware ordering of nodes */
>> local_node = pgdat->node_id;
>> load = nr_online_nodes;
>> prev_node = local_node;
>> - nodes_clear(used_mask);
>>
>> memset(node_order, 0, sizeof(node_order));
>> while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
>>
>
> Honestly, I don't think it's really worth doing a patch for this, but
> there's nothing wrong with the diff, so:
>
> Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>

With the changed subject/description

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>


--
Thanks,

David / dhildenb