[src/trunk]: src/sys/arch/aarch64 Deal with the pmap limitation of maxproc in...

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

details:   https://anonhg.NetBSD.org/src/rev/fa76fbfff08c
branches:  trunk
changeset: 983547:fa76fbfff08c
user:      skrll <skrll%NetBSD.org@localhost>
date:      Sat May 29 06:54:20 2021 +0000

description:
Deal with the pmap limitation of maxproc in a more complete way and
recognise CPUs with only 8bit ASIDs.

diffstat:

 sys/arch/aarch64/aarch64/pmap.c |  14 ++++++--------
 sys/arch/aarch64/include/cpu.h  |  19 +++++++++++++++++--
 2 files changed, 23 insertions(+), 10 deletions(-)

diffs (75 lines):

diff -r 80205fb775e4 -r fa76fbfff08c sys/arch/aarch64/aarch64/pmap.c
--- a/sys/arch/aarch64/aarch64/pmap.c   Sat May 29 06:37:21 2021 +0000
+++ b/sys/arch/aarch64/aarch64/pmap.c   Sat May 29 06:54:20 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.c,v 1.107 2021/04/30 20:07:22 skrll Exp $ */
+/*     $NetBSD: pmap.c,v 1.108 2021/05/29 06:54:20 skrll Exp $ */
 
 /*
  * Copyright (c) 2017 Ryo Shimizu <ryo%nerv.org@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.107 2021/04/30 20:07:22 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.108 2021/05/29 06:54:20 skrll Exp $");
 
 #include "opt_arm_debug.h"
 #include "opt_ddb.h"
@@ -554,6 +554,10 @@
        pool_cache_bootstrap(&_pmap_pv_pool, sizeof(struct pv_entry),
            32, 0, PR_LARGECACHE, "pvpl", NULL, IPL_NONE, _pmap_pv_ctor,
            NULL, NULL);
+
+       int nmaxproc = cpu_maxproc();
+       if (maxproc > nmaxproc)
+               maxproc = nmaxproc;
 }
 
 void
@@ -1420,12 +1424,6 @@
        pm_unlock(pm);
 }
 
-/* XXX: due to the current implementation of pmap depends on 16bit ASID */
-int
-cpu_maxproc(void)
-{
-       return 65535;
-}
 
 void
 pmap_activate(struct lwp *l)
diff -r 80205fb775e4 -r fa76fbfff08c sys/arch/aarch64/include/cpu.h
--- a/sys/arch/aarch64/include/cpu.h    Sat May 29 06:37:21 2021 +0000
+++ b/sys/arch/aarch64/include/cpu.h    Sat May 29 06:54:20 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu.h,v 1.35 2021/05/29 06:37:21 skrll Exp $ */
+/* $NetBSD: cpu.h,v 1.36 2021/05/29 06:54:20 skrll Exp $ */
 
 /*-
  * Copyright (c) 2014, 2020 The NetBSD Foundation, Inc.
@@ -149,7 +149,22 @@
 #undef curlwp
 #define        curlwp                  (aarch64_curlwp())
 
-int    cpu_maxproc(void);
+static inline int
+cpu_maxproc(void)
+{
+       /*
+        * the pmap uses PID for ASID.
+        */
+       switch (__SHIFTOUT(reg_id_aa64mmfr0_el1_read(), ID_AA64MMFR0_EL1_ASIDBITS)) {
+       case ID_AA64MMFR0_EL1_ASIDBITS_8BIT:
+               return (1U << 8) - 1;
+       case ID_AA64MMFR0_EL1_ASIDBITS_16BIT:
+               return (1U << 16) - 1;
+       default:
+               return 0;
+       }
+}
+
 void   cpu_signotify(struct lwp *l);
 void   cpu_need_proftick(struct lwp *l);