[src/trunk]: src/sys/arch/sparc/sparc Optimize xcall() et.al. further by main...

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

details:   https://anonhg.NetBSD.org/src/rev/06165a096aa4
branches:  trunk
changeset: 542203:06165a096aa4
user:      pk <pk%NetBSD.org@localhost>
date:      Thu Jan 23 19:54:35 2003 +0000

description:
Optimize xcall() et.al. further by maintaining a cpuset mask of all CPUs
marked ready. This saves repeated testing for NULL pointers and the
CPUFLG_READY flag.
Also use a separate flag variable to signal xcall completion. This saves a
load and a pipeline stall.

diffstat:

 sys/arch/sparc/sparc/cpu.c    |  29 +++++++++++++++++++----------
 sys/arch/sparc/sparc/cpuvar.h |   4 +++-
 sys/arch/sparc/sparc/intr.c   |   6 ++++--
 3 files changed, 26 insertions(+), 13 deletions(-)

diffs (140 lines):

diff -r b4c726c3c1be -r 06165a096aa4 sys/arch/sparc/sparc/cpu.c
--- a/sys/arch/sparc/sparc/cpu.c        Thu Jan 23 18:57:09 2003 +0000
+++ b/sys/arch/sparc/sparc/cpu.c        Thu Jan 23 19:54:35 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpu.c,v 1.172 2003/01/23 14:54:33 pk Exp $ */
+/*     $NetBSD: cpu.c,v 1.173 2003/01/23 19:54:35 pk Exp $ */
 
 /*
  * Copyright (c) 1996
@@ -102,6 +102,7 @@
 
 int    ncpu;                           /* # of CPUs detected by PROM */
 struct cpu_info **cpus;
+u_int  cpu_ready_mask;                 /* the set of CPUs marked as READY */
 static int cpu_instance;               /* current # of CPUs wired by us */
 
 
@@ -466,6 +467,10 @@
        cpi->redzone = (void *)((long)cpi->idle_u + REDSIZE);
 #endif
 
+       /*
+        * Allocate a slot in the cpus[] array such that the following
+        * invariant holds: cpus[cpi->ci_cpuid] == cpi;
+        */
        cpus[cpu_instance] = cpi;
        cpi->ci_cpuid = cpu_instance++;
        cpi->mid = mid;
@@ -540,9 +545,6 @@
                return;
        }
 
-       if (cpus == NULL)
-               return;
-
        printf("cpu0: booting secondary processors:");
        for (n = 0; n < ncpu; n++) {
                struct cpu_info *cpi = cpus[n];
@@ -559,13 +561,16 @@
 
                printf(" cpu%d", cpi->ci_cpuid);
                cpi->flags |= CPUFLG_READY;
+               cpu_ready_mask |= (1 << n);
        }
 
+       /* Mark the boot CPU as ready */
+       cpuinfo.flags |= CPUFLG_READY;
+       cpu_ready_mask |= (1 << 0);
+
        /* Tell the other CPU's to start up.  */
        go_smp_cpus = 1;
 
-       /* OK, we're done. */
-       cpuinfo.flags |= CPUFLG_READY;
        printf("\n");
 }
 #endif /* MULTIPROCESSOR */
@@ -664,6 +669,9 @@
                return;
        }
 
+       /* Mask any CPUs that are not ready */
+       cpuset &= cpu_ready_mask;
+
        /* prevent interrupts that grab the kernel lock */
        s = splsched();
 #ifdef DEBUG
@@ -685,11 +693,12 @@
        for (n = 0; n < ncpu; n++) {
                struct cpu_info *cpi = cpus[n];
 
-               if (cpi == NULL || (cpuset & (1 << cpi->ci_cpuid)) == 0)
+               /* Note: n == cpi->ci_cpuid */
+               if ((cpuset & (1 << n)) == 0)
                        continue;
 
                cpi->msg.tag = XPMSG_FUNC;
-               cpi->flags &= ~CPUFLG_GOTMSG;
+               cpi->msg.complete = 0;
                p = &cpi->msg.u.xpmsg_func;
                p->func = func;
                p->arg0 = arg0;
@@ -723,10 +732,10 @@
                for (n = 0; n < ncpu; n++) {
                        struct cpu_info *cpi = cpus[n];
 
-                       if (cpi == NULL || (cpuset & (1 << cpi->ci_cpuid)) == 0)
+                       if ((cpuset & (1 << n)) == 0)
                                continue;
 
-                       if ((cpi->flags & CPUFLG_GOTMSG) == 0) {
+                       if (cpi->msg.complete == 0) {
                                if (i < 0) {
                                        printf_nolog(" cpu%d", cpi->ci_cpuid);
                                } else {
diff -r b4c726c3c1be -r 06165a096aa4 sys/arch/sparc/sparc/cpuvar.h
--- a/sys/arch/sparc/sparc/cpuvar.h     Thu Jan 23 18:57:09 2003 +0000
+++ b/sys/arch/sparc/sparc/cpuvar.h     Thu Jan 23 19:54:35 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: cpuvar.h,v 1.56 2003/01/23 18:49:08 pk Exp $ */
+/*     $NetBSD: cpuvar.h,v 1.57 2003/01/23 19:54:35 pk Exp $ */
 
 /*
  *  Copyright (c) 1996 The NetBSD Foundation, Inc.
@@ -103,6 +103,8 @@
                        int     retval;
                } xpmsg_func;
        } u;
+       __volatile int  received;
+       __volatile int  complete;
 };
 
 /*
diff -r b4c726c3c1be -r 06165a096aa4 sys/arch/sparc/sparc/intr.c
--- a/sys/arch/sparc/sparc/intr.c       Thu Jan 23 18:57:09 2003 +0000
+++ b/sys/arch/sparc/sparc/intr.c       Thu Jan 23 19:54:35 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: intr.c,v 1.77 2003/01/23 14:56:06 pk Exp $ */
+/*     $NetBSD: intr.c,v 1.78 2003/01/23 19:54:35 pk Exp $ */
 
 /*
  * Copyright (c) 1992, 1993
@@ -357,6 +357,7 @@
 static void xcallintr(void *v)
 {
 
+       /* notyet - cpuinfo.msg.received = 1; */
        switch (cpuinfo.msg.tag) {
        case XPMSG_FUNC:
            {
@@ -367,7 +368,8 @@
                break;
            }
        }
-       cpuinfo.flags |= CPUFLG_GOTMSG;
+       cpuinfo.msg.tag = 0;
+       cpuinfo.msg.complete = 1;
 }
 #endif /* MULTIPROCESSOR */
 #endif /* SUN4M || SUN4D */