Very rough first cut at NUMA support for the physical page allocator. For

now it uses a very dumb first-touch allocation policy.  This will change in
the future.
- Each architecture indicates the maximum number of supported memory domains
  via a new VM_NDOMAIN parameter in <machine/vmparam.h>.
- Each cpu now has a PCPU_GET(domain) member to indicate the memory domain
  a CPU belongs to.  Domain values are dense and numbered from 0.
- When a platform supports multiple domains, the default freelist
  (VM_FREELIST_DEFAULT) is split up into N freelists, one for each domain.
  The MD code is required to populate an array of mem_affinity structures.
  Each entry in the array defines a range of memory (start and end) and a
  domain for the range.  Multiple entries may be present for a single
  domain.  The list is terminated by an entry where all fields are zero.
  This array of structures is used to split up phys_avail[] regions that
  fall in VM_FREELIST_DEFAULT into per-domain freelists.
- Each memory domain has a separate lookup-array of freelists that is
  used when fulfulling a physical memory allocation.  Right now the
  per-domain freelists are listed in a round-robin order for each domain.
  In the future a table such as the ACPI SLIT table may be used to order
  the per-domain lookup lists based on the penalty for each memory domain
  relative to a specific domain.  The lookup lists may be examined via a
  new vm.phys.lookup_lists sysctl.
- The first-touch policy is implemented by using PCPU_GET(domain) to
  pick a lookup list when allocating memory.

Reviewed by:	alc

1 files changed, 9 insertions, 0 deletions

diff --git a/sys/vm/vm_phys.h b/sys/vm/vm_phys.h
index 0dbd96a..a5b9e93 100644
--- a/sys/vm/vm_phys.h
+++ b/sys/vm/vm_phys.h
@@ -40,6 +40,15 @@
 
 #ifdef _KERNEL
 
+/* Domains must be dense (non-sparse) and zero-based. */
+struct mem_affinity {
+	vm_paddr_t start;
+	vm_paddr_t end;
+	int domain;
+};
+
+extern struct mem_affinity *mem_affinity;
+
 void vm_phys_add_page(vm_paddr_t pa);
 vm_page_t vm_phys_alloc_contig(unsigned long npages,
     vm_paddr_t low, vm_paddr_t high,