Add two new kernel options to control memory locality on NUMA hardware.

 - UMA_XDOMAIN enables an additional per-cpu bucket for freed memory that
   was freed on a different domain from where it was allocated.  This is
   only used for UMA_ZONE_NUMA (first-touch) zones.
 - UMA_FIRSTTOUCH sets the default UMA policy to be first-touch for all
   zones.  This tries to maintain locality for kernel memory.

Reviewed by:	gallatin, alc, kib
Tested by:	pho, gallatin
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D20929

1 files changed, 20 insertions, 0 deletions

diff --git a/sys/vm/vm_phys.c b/sys/vm/vm_phys.c
index 48e7f6c9a795..c16282974a40 100644
--- a/sys/vm/vm_phys.c
+++ b/sys/vm/vm_phys.c
@@ -623,6 +623,26 @@ vm_phys_register_domains(int ndomains, struct mem_affinity *affinity,
 #endif
 }
 
+int
+_vm_phys_domain(vm_paddr_t pa)
+{
+#ifdef NUMA
+	int i;
+
+	if (vm_ndomains == 1 || mem_affinity == NULL)
+		return (0);
+
+	/*
+	 * Check for any memory that overlaps.
+	 */
+	for (i = 0; mem_affinity[i].end != 0; i++)
+		if (mem_affinity[i].start <= pa &&
+		    mem_affinity[i].end >= pa)
+			return (mem_affinity[i].domain);
+#endif
+	return (0);
+}
+
 /*
  * Split a contiguous, power of two-sized set of physical pages.
  *