- Add a pmap pointer to struct md_page, and use this to find the pmap that

  a mapping belongs to by setting it in the vm_page_t structure that backs
  the tsb page that the tte for a mapping is in.  This allows the pmap that
  a mapping belongs to to be found without keeping a pointer to it in the
  tte itself.
- Remove the pmap pointer from struct tte and use the space to make the
  tte pv lists doubly linked (TAILQs), like on other architectures.  This
  makes entering or removing a mapping O(1) instead of O(n) where n is the
  number of pmaps a page is mapped by (including kernel_pmap).
- Use atomic ops for setting and clearing bits in the ttes, now that they
  return the old value and can be easily used for this purpose.
- Use __builtin_memset for zeroing ttes instead of bzero, so that gcc will
  inline it (4 inline stores using %g0 instead of a function call).
- Initially set the virtual colour for all the vm_page_ts to be equal to their
  physical colour.  This will be more useful once uma_small_alloc is
  implemented, but basically pages with virtual colour equal to phsyical
  colour are easier to handle at the pmap level because they can be safely
  accessed through cachable direct virtual to physical mappings with that
  colour, without fear of causing illegal dcache aliases.

In total these changes give a minor performance improvement, about 1%
reduction in system time during buildworld.

1 files changed, 1 insertions, 2 deletions

diff --git a/sys/sparc64/sparc64/tsb.c b/sys/sparc64/sparc64/tsb.c
index a2293cd..2be5d97 100644
--- a/sys/sparc64/sparc64/tsb.c
+++ b/sys/sparc64/sparc64/tsb.c
@@ -183,8 +183,7 @@ enter:
 
 	tp->tte_vpn = TV_VPN(va, sz);
 	tp->tte_data = data;
-	STAILQ_INSERT_TAIL(&m->md.tte_list, tp, tte_link);
-	tp->tte_pmap = pm;
+	TAILQ_INSERT_TAIL(&m->md.tte_list, tp, tte_link);
 
 	return (tp);
 }