[src/trunk]: src/sys/arch/arm/pic pic: avoid pic_do_pending_ints if pic_mark_...

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

details:   https://anonhg.NetBSD.org/src/rev/51febc655364
branches:  trunk
changeset: 959526:51febc655364
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Tue Feb 16 22:12:49 2021 +0000

description:
pic: avoid pic_do_pending_ints if pic_mark_pending_* has never been called

diffstat:

 sys/arch/arm/pic/pic.c          |  13 ++++++++-
 sys/arch/arm/pic/pic_splfuncs.c |  54 +++++++++++++++++++++++++---------------
 2 files changed, 45 insertions(+), 22 deletions(-)

diffs (140 lines):

diff -r 1eff29befff8 -r 51febc655364 sys/arch/arm/pic/pic.c
--- a/sys/arch/arm/pic/pic.c    Tue Feb 16 19:46:15 2021 +0000
+++ b/sys/arch/arm/pic/pic.c    Tue Feb 16 22:12:49 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pic.c,v 1.64 2021/02/15 16:32:07 jmcneill Exp $        */
+/*     $NetBSD: pic.c,v 1.65 2021/02/16 22:12:49 jmcneill Exp $        */
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
  * All rights reserved.
@@ -33,7 +33,7 @@
 #include "opt_multiprocessor.h"
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pic.c,v 1.64 2021/02/15 16:32:07 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pic.c,v 1.65 2021/02/16 22:12:49 jmcneill Exp $");
 
 #include <sys/param.h>
 #include <sys/atomic.h>
@@ -59,6 +59,9 @@
 #include <arm/pic/picvar.h>
 
 #if defined(__HAVE_PIC_PENDING_INTRS)
+
+bool pic_pending_used __read_mostly = false;
+
 /*
  * This implementation of pending interrupts on a MULTIPROCESSOR system makes
  * the assumption that a PIC (pic_softc) shall only have all its interrupts
@@ -279,6 +282,9 @@
 {
        const uint32_t ipl_mask = __BIT(is->is_ipl);
 
+       if (!pic_pending_used)
+               pic_pending_used = true;
+
        atomic_or_32(&pic->pic_pending_irqs[is->is_irq >> 5],
            __BIT(is->is_irq & 0x1f));
 
@@ -309,6 +315,9 @@
        volatile uint32_t *ipending = &pic->pic_pending_irqs[irq_base >> 5];
        uint32_t ipl_mask = 0;
 
+       if (!pic_pending_used)
+               pic_pending_used = true;
+
        if (pending == 0)
                return ipl_mask;
 
diff -r 1eff29befff8 -r 51febc655364 sys/arch/arm/pic/pic_splfuncs.c
--- a/sys/arch/arm/pic/pic_splfuncs.c   Tue Feb 16 19:46:15 2021 +0000
+++ b/sys/arch/arm/pic/pic_splfuncs.c   Tue Feb 16 22:12:49 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pic_splfuncs.c,v 1.12 2021/02/15 16:32:07 jmcneill Exp $       */
+/*     $NetBSD: pic_splfuncs.c,v 1.13 2021/02/16 22:12:50 jmcneill Exp $       */
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
  * All rights reserved.
@@ -28,7 +28,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pic_splfuncs.c,v 1.12 2021/02/15 16:32:07 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pic_splfuncs.c,v 1.13 2021/02/16 22:12:50 jmcneill Exp $");
 
 #define _INTR_PRIVATE
 #include <sys/param.h>
@@ -46,6 +46,11 @@
 
 #include <arm/pic/picvar.h>
 
+#if defined(__HAVE_PIC_PENDING_INTRS)
+extern bool pic_pending_used;
+#else
+#define pic_pending_used       false
+#endif
 
 int
 _splraise(int newipl)
@@ -65,12 +70,16 @@
        const int oldipl = ci->ci_cpl;
        KASSERT(panicstr || newipl <= ci->ci_cpl);
        if (newipl < ci->ci_cpl) {
-               register_t psw = cpsid(I32_bit);
-               ci->ci_intr_depth++;
-               pic_do_pending_ints(psw, newipl, NULL);
-               ci->ci_intr_depth--;
-               if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
-                       cpsie(I32_bit);
+               if (__predict_false(pic_pending_used)) {
+                       register_t psw = cpsid(I32_bit);
+                       ci->ci_intr_depth++;
+                       pic_do_pending_ints(psw, newipl, NULL);
+                       ci->ci_intr_depth--;
+                       if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
+                               cpsie(I32_bit);
+               } else {
+                       pic_set_priority(ci, newipl);
+               }
                cpu_dosoftints();
        }
        return oldipl;
@@ -86,21 +95,26 @@
                return;
        }
 
-       register_t psw = cpsid(I32_bit);
-       KASSERTMSG(panicstr != NULL || savedipl < ci->ci_cpl,
-           "splx(%d) to a higher ipl than %d", savedipl, ci->ci_cpl);
+       if (__predict_false(pic_pending_used)) {
+               register_t psw = cpsid(I32_bit);
+               KASSERTMSG(panicstr != NULL || savedipl < ci->ci_cpl,
+                   "splx(%d) to a higher ipl than %d", savedipl, ci->ci_cpl);
 
-       if ((psw & I32_bit) == 0) {
-               ci->ci_intr_depth++;
-               pic_do_pending_ints(psw, savedipl, NULL);
-               ci->ci_intr_depth--;
-               KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
-                   ci->ci_cpl, savedipl);
+               if ((psw & I32_bit) == 0) {
+                       ci->ci_intr_depth++;
+                       pic_do_pending_ints(psw, savedipl, NULL);
+                       ci->ci_intr_depth--;
+                       KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
+                           ci->ci_cpl, savedipl);
 
-               cpsie(I32_bit);
+                       cpsie(I32_bit);
+                       cpu_dosoftints();
+               } else {
+                       pic_set_priority_psw(ci, psw, savedipl);
+               }
+       } else {
+               pic_set_priority(ci, savedipl);
                cpu_dosoftints();
-       } else {
-               pic_set_priority_psw(ci, psw, savedipl);
        }
 
        KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",