[src/trunk]: src/sys/arch/sparc/sparc Drop the special sun4d `tlb flush' lock...

[pk <pk%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/903a09b461af
branches:  trunk
changeset: 565565:903a09b461af
user:      pk <pk%NetBSD.org@localhost>
date:      Mon Apr 12 14:26:01 2004 +0000

description:
Drop the special sun4d `tlb flush' lock. The pte update function already
serialises access to the PTEs to reliably get ref/mod bits.

Rename pte4m_lock => demap_lock.

diffstat:

 sys/arch/sparc/sparc/pmap.c |  34 +++++++---------------------------
 1 files changed, 7 insertions(+), 27 deletions(-)

diffs (118 lines):

diff -r 627ebac0dbdc -r 903a09b461af sys/arch/sparc/sparc/pmap.c
--- a/sys/arch/sparc/sparc/pmap.c       Mon Apr 12 13:17:46 2004 +0000
+++ b/sys/arch/sparc/sparc/pmap.c       Mon Apr 12 14:26:01 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.c,v 1.287 2004/04/12 12:52:42 pk Exp $ */
+/*     $NetBSD: pmap.c,v 1.288 2004/04/12 14:26:01 pk Exp $ */
 
 /*
  * Copyright (c) 1996
@@ -56,7 +56,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.287 2004/04/12 12:52:42 pk Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.288 2004/04/12 14:26:01 pk Exp $");
 
 #include "opt_ddb.h"
 #include "opt_kgdb.h"
@@ -674,20 +674,10 @@
 #if defined(MULTIPROCESSOR)
 /*
  * The SMP versions of the tlb flush routines.  We only need to
- * do a cross call for these on sun4m systems, which itself
- * ensures that there is only one concurrent flush happening.
- * For the sun4d case, we provide a special lock.
+ * do a cross call for these on sun4m (Mbus) systems. sun4d systems
+ * have an Xbus which broadcasts TLB demaps in hardware.
  */
 
-#if defined(SUN4D)
-static struct simplelock sun4d_tlb_lock = SIMPLELOCK_INITIALIZER;
-#define LOCK_4DTLB()   simple_lock(&sun4d_tlb_lock);
-#define UNLOCK_4DTLB() simple_unlock(&sun4d_tlb_lock);
-#else
-#define LOCK_4DTLB()   /* nothing */
-#define UNLOCK_4DTLB() /* nothing */
-#endif
-
 static __inline__ void smp_tlb_flush_page (int va, int ctx, u_int cpuset);
 static __inline__ void smp_tlb_flush_segment (int va, int ctx, u_int cpuset);
 static __inline__ void smp_tlb_flush_region (int va, int ctx, u_int cpuset);
@@ -698,9 +688,7 @@
 smp_tlb_flush_page(int va, int ctx, u_int cpuset)
 {
        if (CPU_ISSUN4D) {
-               LOCK_4DTLB();
                sp_tlb_flush(va, ctx, ASI_SRMMUFP_L3);
-               UNLOCK_4DTLB();
        } else
                XCALL3(sp_tlb_flush, va, ctx, ASI_SRMMUFP_L3, cpuset);
 }
@@ -709,9 +697,7 @@
 smp_tlb_flush_segment(int va, int ctx, u_int cpuset)
 {
        if (CPU_ISSUN4D) {
-               LOCK_4DTLB();
                sp_tlb_flush(va, ctx, ASI_SRMMUFP_L2);
-               UNLOCK_4DTLB();
        } else
                XCALL3(sp_tlb_flush, va, ctx, ASI_SRMMUFP_L2, cpuset);
 }
@@ -720,9 +706,7 @@
 smp_tlb_flush_region(int va, int ctx, u_int cpuset)
 {
        if (CPU_ISSUN4D) {
-               LOCK_4DTLB();
                sp_tlb_flush(va, ctx, ASI_SRMMUFP_L1);
-               UNLOCK_4DTLB();
        } else
                XCALL3(sp_tlb_flush, va, ctx, ASI_SRMMUFP_L1, cpuset);
 }
@@ -731,9 +715,7 @@
 smp_tlb_flush_context(int ctx, u_int cpuset)
 {
        if (CPU_ISSUN4D) {
-               LOCK_4DTLB();
                sp_tlb_flush(ctx, 0, ASI_SRMMUFP_L0);
-               UNLOCK_4DTLB();
        } else
                XCALL3(sp_tlb_flush, 0, ctx, ASI_SRMMUFP_L0, cpuset);
 }
@@ -742,9 +724,7 @@
 smp_tlb_flush_all()
 {
        if (CPU_ISSUN4D) {
-               LOCK_4DTLB();
                sp_tlb_flush_all();
-               UNLOCK_4DTLB();
        } else
                XCALL0(sp_tlb_flush_all, CPUSET_ALL);
 }
@@ -822,7 +802,7 @@
  * PTE at the same time we are.  This is the procedure that is
  * recommended in the SuperSPARC user's manual.
  */
-static struct simplelock pte4m_lock = SIMPLELOCK_INITIALIZER;
+static struct simplelock demap_lock = SIMPLELOCK_INITIALIZER;
 
 int
 updatepte4m(va, pte, bic, bis, ctx, cpuset)
@@ -840,7 +820,7 @@
         * Can only be one of these happening in the system
         * at any one time.
         */
-       simple_lock(&pte4m_lock);
+       simple_lock(&demap_lock);
 
        /*
         * The idea is to loop swapping zero into the pte, flushing
@@ -859,7 +839,7 @@
        swapval = (oldval & ~bic) | bis;
        swap(vpte, swapval);
 
-       simple_unlock(&pte4m_lock);
+       simple_unlock(&demap_lock);
 
        return (oldval);
 }