Re: [PATCH] x86: numa: mm: kill double initialization for NODE_DATA

[Wanpeng Li <liwanp@linux.vnet.ibm.com>]

On Wed, Apr 03, 2013 at 09:54:33AM +0800, Lin Feng wrote:
>Hi Wanpeng,
>
>On 04/02/2013 06:57 PM, Wanpeng Li wrote:
>>> >PS. For clarifying calling chains are showed as follows:
>>> >setup_arch()
>>> >  ...
>>> >  initmem_init()
>>> >    x86_numa_init()
>>> >      numa_init()
>>> >        numa_register_memblks()
>>> >          setup_node_data()
>>> >            NODE_DATA(nid)->node_id = nid;
>>> >            NODE_DATA(nid)->node_start_pfn = start >> PAGE_SHIFT;
>>> >            NODE_DATA(nid)->node_spanned_pages = (end - start) >> PAGE_SHIFT;
>>> >  ...
>>> >  x86_init.paging.pagetable_init()
>>> >  paging_init()
>>> >    ...
>>> >    sparse_init()
>>> >      sparse_early_usemaps_alloc_node()
>>> >        sparse_early_usemaps_alloc_pgdat_section()
>>> >          ___alloc_bootmem_node_nopanic()
>>> >            __alloc_memory_core_early(pgdat->node_id,...)
>>> >    ...
>>> >    zone_sizes_init()
>>> >      free_area_init_nodes()
>>> >        free_area_init_node()
>>> >          pgdat->node_id = nid;
>>> >          pgdat->node_start_pfn = node_start_pfn;
>>> >          calculate_node_totalpages();
>>> >            pgdat->node_spanned_pages = totalpages;
>>> >
>> You miss the nodes which could become online at some point, but not
>> online currently. 
>

Hi Feng,

>Sorry, I'm not quite understanding what you said.
>
>I keep node_set_online(nid) there. In boot phase if a node is online now it wil be 
>reinitialized later by zone_sizes_init() else if a node is hotpluged after system is
>up it will also be initialized by hotadd_new_pgdat() which falls into calling 
>free_area_init_node().

I miss it.

>
>Besides this I'm not sure there are any other dependency besides what you worry about,
>while I tested this on a x86_64 numa system with hot-add nodes and the meminfo statics
>looks right before and after hot-add memory.

Fair enough. ;-)

Regards,
Wanpeng Li 

>
>thanks for your patient,
>linfeng

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>