Re: [Qemu-devel] [PATCH 3/7] spapr: Refactor spapr_populate_memory()

[Alexey Kardashevskiy]

On 06/21/2014 08:55 AM, Nishanth Aravamudan wrote:
> On 16.06.2014 [17:53:49 +1000], Alexey Kardashevskiy wrote:
>> Current QEMU does not support memoryless NUMA nodes.
>> This prepares SPAPR for that.
>>
>> This moves 2 calls of spapr_populate_memory_node() into
>> the existing loop which handles nodes other than than
>> the first one.
>>
>> Signed-off-by: Alexey Kardashevskiy <address@hidden>
>> ---
>>  hw/ppc/spapr.c | 31 +++++++++++--------------------
>>  1 file changed, 11 insertions(+), 20 deletions(-)
>>
>> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
>> index cb3a10a..666b676 100644
>> --- a/hw/ppc/spapr.c
>> +++ b/hw/ppc/spapr.c
>> @@ -689,28 +689,13 @@ static void spapr_populate_memory_node(void *fdt, int 
>> nodeid, hwaddr start,
>>
>>  static int spapr_populate_memory(sPAPREnvironment *spapr, void *fdt)
>>  {
>> -    hwaddr node0_size, mem_start, node_size;
>> +    hwaddr mem_start, node_size;
>>      int i;
>>
>> -    /* memory node(s) */
>> -    if (nb_numa_nodes > 1 && node_mem[0] < ram_size) {
>> -        node0_size = node_mem[0];
>> -    } else {
>> -        node0_size = ram_size;
>> -    }
>> -
>> -    /* RMA */
>> -    spapr_populate_memory_node(fdt, 0, 0, spapr->rma_size);
>> -
>> -    /* RAM: Node 0 */
>> -    if (node0_size > spapr->rma_size) {
>> -        spapr_populate_memory_node(fdt, 0, spapr->rma_size,
>> -                                   node0_size - spapr->rma_size);
>> -    }
>> -
>> -    /* RAM: Node 1 and beyond */
>> -    mem_start = node0_size;
>> -    for (i = 1; i < nb_numa_nodes; i++) {
>> +    for (i = 0, mem_start = 0; i < nb_numa_nodes; ++i) {
>> +        if (!node_mem[i]) {
>> +            continue;
>> +        }
> 
> Doesn't this skip memoryless nodes? What actually puts the memoryless
> node in the device-tree?

It does skip.

> And if you were to put them in, wouldn't spapr_populate_memory_node()
> fail because we'd be creating two nodes with address@hidden where XXX is the
> same (starting address) for both?

I cannot do this now - there is no way to tell from the command line where
I want NUMA node memory start from so I'll end up with multiple nodes with
the same name and QEMU won't start. When NUMA fixes reach upstream, I'll
try to work out something on top of that.


-- 
Alexey