Allocate the VHPT for each CPU in cpu_mp_start(), rather than

allocating MAXCPU VHPTs up-front. This allows us to max-out MAXCPU
without memory waste -- MAXCPU is now 32 for SMP kernels.

This change also eliminates the VHPT scaling based in the total
memory in the system. It's the workload that determines the best size
of the VHPT. The workload can be affected by the amount of memory,
but not necessarily. For example, there's no performance difference
between VHPT sizes of 256KB, 512KB and 1MB when building the LINT
kernel. This was observed with a system that has 8GB of memory.
By default the kernel will allocate a 1MB VHPT. The user can tune the
system with the "machdep.vhpt.log2size" tunable.

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/ia64/include/pmap.h b/sys/ia64/include/pmap.h
index c6b9754..f878d27 100644
--- a/sys/ia64/include/pmap.h
+++ b/sys/ia64/include/pmap.h
@@ -125,6 +125,7 @@ extern int pmap_vhpt_log2size;
 #define	pmap_unmapbios(va, sz)	pmap_unmapdev(va, sz)
 
 vm_offset_t pmap_steal_memory(vm_size_t);
+vm_offset_t pmap_alloc_vhpt(void);
 void	pmap_bootstrap(void);
 void	pmap_kenter(vm_offset_t va, vm_offset_t pa);
 vm_paddr_t pmap_kextract(vm_offset_t va);