[src/trunk]: src/sys/arch/sparc/sparc in cpu_switchto(), remove the MP-unsafe...

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

details:   https://anonhg.NetBSD.org/src/rev/89dc3b8c07a7
branches:  trunk
changeset: 782473:89dc3b8c07a7
user:      chs <chs%NetBSD.org@localhost>
date:      Sun Nov 04 00:32:47 2012 +0000

description:
in cpu_switchto(), remove the MP-unsafe code to mark a pmap active on a CPU,
pmap_activate() already does this.  add MP locking to pmap_activate()
and pmap_deactivate().  move flushing of user windows and virtual caches
from pamp_activate() to pmap_deactivate().

diffstat:

 sys/arch/sparc/sparc/locore.s |  15 +--------
 sys/arch/sparc/sparc/pmap.c   |  73 +++++++++++++++++++-----------------------
 2 files changed, 34 insertions(+), 54 deletions(-)

diffs (133 lines):

diff -r 7e7f74d31227 -r 89dc3b8c07a7 sys/arch/sparc/sparc/locore.s
--- a/sys/arch/sparc/sparc/locore.s     Sat Nov 03 23:42:27 2012 +0000
+++ b/sys/arch/sparc/sparc/locore.s     Sun Nov 04 00:32:47 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: locore.s,v 1.267 2012/11/02 00:01:19 chs Exp $ */
+/*     $NetBSD: locore.s,v 1.268 2012/11/04 00:32:47 chs Exp $ */
 
 /*
  * Copyright (c) 1996 Paul Kranenburg
@@ -4935,19 +4935,6 @@
        /*
         * Now running p.  
         */
-#if defined(MULTIPROCESSOR)
-       ld      [%g3 + L_PROC], %o2     ! p = l->l_proc;
-       ld      [%o2 + P_VMSPACE], %o3  ! vm = p->p_vmspace;
-       ld      [%o3 + VM_PMAP], %o4    ! pm = vm->vm_map.vm_pmap;
-       /* Add this CPU to the pmap's CPU set */
-       sethi   %hi(CPUINFO_VA + CPUINFO_CPUNO), %o0
-       ld      [%o0 + %lo(CPUINFO_VA + CPUINFO_CPUNO)], %o1
-       mov     1, %o2
-       ld      [%o4 + PMAP_CPUSET], %o0
-       sll     %o2, %o1, %o2
-       or      %o0, %o2, %o0           ! pm->pm_cpuset |= cpu_number();
-       st      %o0, [%o4 + PMAP_CPUSET]
-#endif
 
        /*
         * Check for restartable atomic sequences (RAS)
diff -r 7e7f74d31227 -r 89dc3b8c07a7 sys/arch/sparc/sparc/pmap.c
--- a/sys/arch/sparc/sparc/pmap.c       Sat Nov 03 23:42:27 2012 +0000
+++ b/sys/arch/sparc/sparc/pmap.c       Sun Nov 04 00:32:47 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.c,v 1.348 2012/01/29 11:49:58 para Exp $ */
+/*     $NetBSD: pmap.c,v 1.349 2012/11/04 00:32:47 chs Exp $ */
 
 /*
  * Copyright (c) 1996
@@ -56,7 +56,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.348 2012/01/29 11:49:58 para Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.349 2012/11/04 00:32:47 chs Exp $");
 
 #include "opt_ddb.h"
 #include "opt_kgdb.h"
@@ -7440,31 +7440,19 @@
 pmap_activate(struct lwp *l)
 {
        pmap_t pm = l->l_proc->p_vmspace->vm_map.pmap;
-       int s;
-
-       /*
-        * This is essentially the same thing that happens in cpu_switch()
-        * when the newly selected process is about to run, except that we
-        * have to make sure to clean the register windows before we set
-        * the new context.
-        */
-
-       s = splvm();
-       if (l == curlwp) {
-               write_user_windows();
-               if (pm->pm_ctx == NULL) {
-                       ctx_alloc(pm);  /* performs setcontext() */
-               } else {
-                       /* Do any cache flush needed on context switch */
-                       (*cpuinfo.pure_vcache_flush)();
-                       setcontext(pm->pm_ctxnum);
-               }
-#if defined(MULTIPROCESSOR)
-               if (pm != pmap_kernel())
-                       PMAP_SET_CPUSET(pm, &cpuinfo);
-#endif
-       }
-       splx(s);
+
+       if (pm == pmap_kernel() || l != curlwp) {
+               return;
+       }
+
+       PMAP_LOCK();
+       if (pm->pm_ctx == NULL) {
+               ctx_alloc(pm);  /* performs setcontext() */
+       } else {
+               setcontext(pm->pm_ctxnum);
+       }
+       PMAP_SET_CPUSET(pm, &cpuinfo);
+       PMAP_UNLOCK();
 }
 
 /*
@@ -7473,22 +7461,27 @@
 void
 pmap_deactivate(struct lwp *l)
 {
-#if defined(MULTIPROCESSOR)
-       pmap_t pm;
-       struct proc *p;
-
-       p = l->l_proc;
-       if (p->p_vmspace &&
-           (pm = p->p_vmspace->vm_map.pmap) != pmap_kernel()) {
+       struct proc *p = l->l_proc;
+       pmap_t pm = p->p_vmspace->vm_map.pmap;
+
+       if (pm == pmap_kernel() || l != curlwp) {
+               return;
+       }
+
+       write_user_windows();
+       PMAP_LOCK();
+       if (pm->pm_ctx) {
+               (*cpuinfo.pure_vcache_flush)();
+
 #if defined(SUN4M) || defined(SUN4D)
-               if (pm->pm_ctx && CPU_HAS_SRMMU)
+               if (CPU_HAS_SRMMU)
                        sp_tlb_flush(0, pm->pm_ctxnum, ASI_SRMMUFP_L0);
 #endif
-
-               /* we no longer need broadcast tlb flushes for this pmap. */
-               PMAP_CLR_CPUSET(pm, &cpuinfo);
-       }
-#endif
+       }
+
+       /* we no longer need broadcast tlb flushes for this pmap. */
+       PMAP_CLR_CPUSET(pm, &cpuinfo);
+       PMAP_UNLOCK();
 }
 
 #ifdef DEBUG