[src/trunk]: src/sys/arch/arm/arm32 Make TPIDRPRW_IS_CURLWP work for MULTIPRO...

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

details:   https://anonhg.NetBSD.org/src/rev/d158b89b3211
branches:  trunk
changeset: 337253:d158b89b3211
user:      matt <matt%NetBSD.org@localhost>
date:      Wed Apr 08 12:07:40 2015 +0000

description:
Make TPIDRPRW_IS_CURLWP work for MULTIPROCESSOR.
get curcpu() from new lwp.
don't set lwp l_cpu (already done).
Remove support for __HAVE_UNNESTED_INTRS
don't set curlwp until after we are done saving the oldlwp.
disable interrupts when setting curlwp/kernel stack pointer.
Overall, these changes simplify cpu_switchto even more.

diffstat:

 sys/arch/arm/arm32/cpuswitch.S |  69 ++++++++++++++---------------------------
 1 files changed, 24 insertions(+), 45 deletions(-)

diffs (143 lines):

diff -r acae4d0f3a34 -r d158b89b3211 sys/arch/arm/arm32/cpuswitch.S
--- a/sys/arch/arm/arm32/cpuswitch.S    Wed Apr 08 08:35:54 2015 +0000
+++ b/sys/arch/arm/arm32/cpuswitch.S    Wed Apr 08 12:07:40 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpuswitch.S,v 1.89 2015/03/24 21:09:11 skrll Exp $     */
+/*     $NetBSD: cpuswitch.S,v 1.90 2015/04/08 12:07:40 matt Exp $      */
 
 /*
  * Copyright 2003 Wasabi Systems, Inc.
@@ -87,10 +87,10 @@
 #include <arm/asm.h>
 #include <arm/locore.h>
 
-       RCSID("$NetBSD: cpuswitch.S,v 1.89 2015/03/24 21:09:11 skrll Exp $")
+       RCSID("$NetBSD: cpuswitch.S,v 1.90 2015/04/08 12:07:40 matt Exp $")
 
 /* LINTSTUB: include <sys/param.h> */
-       
+
 #undef IRQdisable
 #undef IRQenable
 
@@ -138,38 +138,8 @@
 
 #ifdef TPIDRPRW_IS_CURCPU
        GET_CURCPU(r5)
-#elif defined(TPIDRPRW_IS_CURLWP)
-       mrc     p15, 0, r0, c13, c0, 4          /* get old lwp (r4 maybe 0) */
-       ldr     r5, [r0, #(L_CPU)]              /* get cpu from old lwp */
-#elif !defined(MULTIPROCESSOR) 
+#else
        ldr     r5, [r6, #L_CPU]                /* get cpu from new lwp */
-#else
-#error curcpu() method not defined
-#endif
-
-       /* rem: r4 = old lwp */
-       /* rem: r5 = curcpu() */
-       /* rem: r6 = new lwp */
-       
-#ifndef __HAVE_UNNESTED_INTRS
-       IRQdisable
-#endif
-
-#ifdef MULTIPROCESSOR
-       str     r5, [r6, #(L_CPU)]
-#else
-       /* l->l_cpu initialized in fork1() for single-processor */
-#endif
-
-#if defined(TPIDRPRW_IS_CURLWP)
-       mcr     p15, 0, r6, c13, c0, 4          /* set current lwp */
-#endif
-       /* We have a new curlwp now so make a note it */
-       str     r6, [r5, #(CI_CURLWP)]
-
-       /* At this point we can allow IRQ's again. */
-#ifndef __HAVE_UNNESTED_INTRS
-       IRQenable
 #endif
 
        /* rem: r4 = old lwp */
@@ -226,9 +196,26 @@
        /* Restore saved context */
 
 .Ldo_switch:
+       /* rem: r4 = old lwp */
+       /* rem: r5 = curcpu() */
+       /* rem: r6 = new lwp */
+
+       IRQdisable
+#if defined(TPIDRPRW_IS_CURLWP)
+       mcr     p15, 0, r6, c13, c0, 4          /* set current lwp */
+#endif
+
+       /* We have a new curlwp now so make a note of it */
+       str     r6, [r5, #(CI_CURLWP)]
        /* Get the new pcb */
        ldr     r7, [r6, #(L_PCB)]
 
+       /* make sure we are using the new lwp's stack */
+       ldr     sp, [r7, #(PCB_KSP)]
+
+       /* At this point we can allow IRQ's again. */
+       IRQenable
+
        /* rem: r4 = old lwp */
        /* rem: r5 = curcpu() */
        /* rem: r6 = new lwp */
@@ -292,14 +279,13 @@
        ldr     r10, [r7, #(PCB_R10)]
        ldr     r11, [r7, #(PCB_R11)]
        ldr     r12, [r7, #(PCB_R12)]
-       ldr     r13, [r7, #(PCB_KSP)]   /* sp */
 #elif defined(_ARM_ARCH_DWORD_OK)
        ldrd    r8, r9, [r7, #(PCB_R8)]
        ldrd    r10, r11, [r7, #(PCB_R10)]
-       ldrd    r12, r13, [r7, #(PCB_R12)]      /* sp */
+       ldr     r12, [r7, #(PCB_R12)]
 #else
        add     r0, r7, #PCB_R8
-       ldmia   r0, {r8-r13}
+       ldmia   r0, {r8-r12}
 #endif
 
        /* Record the old lwp for pmap_activate()'s benefit */
@@ -410,9 +396,7 @@
        /* this is an invariant so load before disabling intrs */
        ldr     r2, [r5, #(L_PCB)]      /* get new lwp's pcb */
 
-#ifndef __HAVE_UNNESTED_INTRS
        IRQdisable
-#endif
        /*
         * We're switching to a bound LWP so its l_cpu is already correct.
         */
@@ -429,10 +413,7 @@
        ldr     sp, [r5, #(L_MD_TF)]    /* get new lwp's stack ptr */
 
        /* At this point we can allow IRQ's again. */
-#ifndef __HAVE_UNNESTED_INTRS
        IRQenable
-#endif
-
                                        /* r1 still has ipl */
        mov     r0, r4                  /* r0 has pinned (old) lwp */
        bl      _C_LABEL(softint_dispatch)
@@ -441,14 +422,12 @@
         */
        ldr     r2, [r4, #(L_PCB)]      /* get pinned lwp's pcb */
 
-#ifndef __HAVE_UNNESTED_INTRS
-       IRQdisable
-#endif
        /*
         * We don't need to restore all the registers since another lwp was
         * never executed.  But we do need the SP from the formerly pinned lwp.
         */
 
+       IRQdisable
 #if defined(TPIDRPRW_IS_CURLWP)
        mcr     p15, 0, r4, c13, c0, 4          /* restore pinned lwp */
 #endif