On Mon, May 25, 2015 at 02:42:40PM -0300, Eduardo Habkost wrote: > On Mon, May 25, 2015 at 01:17:57PM +0530, Bharata B Rao wrote: > > On Thu, May 14, 2015 at 11:39:06AM +0200, Paolo Bonzini wrote: > > > On 13/05/2015 20:06, Eduardo Habkost wrote: > > > > Also, this introduces a circular dependency between pc-dimm.c and > > > > numa.c. Instead of that, pc-dimm could simply notify us when a new > > > > device is realized (with just (addr, end, node) as arguments), so we can > > > > save the list of memory ranges inside struct node_info. > > > > > > > > I wonder if the memory API already provides something that would help > > > > us. Paolo, do you see a way we could simply use a MemoryRegion as input > > > > to lookup the NUMA node? > > > > > > No, but I guess you could add a numa_get/set_memory_region_node_id API > > > that uses a hash table. That's a variant of the "pc-dimm could simply > > > notify" numa.c that you propose above. > > > > While you say we can't use MemoryRegion as input to lookup the NUMA node, > > you suggest that we add numa_get/set_memory_region_node_id. Does this API > > get/set NUMA node id for the given MemoryRegion ? > > I was going to suggest that, but it would require changing the > non-memdev code path to create a MemoryRegion for each node, too. So > having a numa_set_mem_node_id(start_addr, end_addr, node_id) API would > be simpler.
In order to save the list of memory ranges inside node_info, I tried this approach where I call numa_set_mem_node_id(dimm.addr, dimm.size, dimm.node) from pc_dimm_realize(), but the value of dimm.addr is finalized only later in ->plug(). So we would have to call this API from arch code like pc_dimm_plug(). Is that acceptable ? Regards, Bharata.
