Module Name: src
Committed By: christos
Date: Fri Oct 9 21:14:05 UTC 2020
Modified Files:
src/sys/arch/x86/x86: cpu.c
Log Message:
Don't do extra work finding the power of 2 for values we are not going to
use. Explain that cpu_hatch has not been called yet, so no cpu_probe either
so the cache info is 0 for AP's.
To generate a diff of this commit:
cvs rdiff -u -r1.198 -r1.199 src/sys/arch/x86/x86/cpu.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/x86/x86/cpu.c
diff -u src/sys/arch/x86/x86/cpu.c:1.198 src/sys/arch/x86/x86/cpu.c:1.199
--- src/sys/arch/x86/x86/cpu.c:1.198 Sun Aug 9 11:32:44 2020
+++ src/sys/arch/x86/x86/cpu.c Fri Oct 9 17:14:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: cpu.c,v 1.198 2020/08/09 15:32:44 christos Exp $ */
+/* $NetBSD: cpu.c,v 1.199 2020/10/09 21:14:05 christos Exp $ */
/*
* Copyright (c) 2000-2020 NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.198 2020/08/09 15:32:44 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpu.c,v 1.199 2020/10/09 21:14:05 christos Exp $");
#include "opt_ddb.h"
#include "opt_mpbios.h" /* for MPDEBUG */
@@ -274,11 +274,17 @@ cpu_pcpuarea_init(struct cpu_info *ci)
static void
cpu_vm_init(struct cpu_info *ci)
{
- int ncolors = 2, i;
+ unsigned int ncolors = 2;
- for (i = CAI_ICACHE; i <= CAI_L2CACHE; i++) {
+ /*
+ * XXX: for AP's the cache info has not been initialized yet
+ * but that does not matter because uvm only pays attention at
+ * the maximum only. We should fix it once cpus have different
+ * cache sizes.
+ */
+ for (unsigned int i = CAI_ICACHE; i <= CAI_L2CACHE; i++) {
struct x86_cache_info *cai;
- int tcolors;
+ unsigned int tcolors;
cai = &ci->ci_cinfo[i];
@@ -293,24 +299,27 @@ cpu_vm_init(struct cpu_info *ci)
default:
tcolors /= cai->cai_associativity;
}
- ncolors = uimax(ncolors, tcolors);
- /*
- * If the desired number of colors is not a power of
- * two, it won't be good. Find the greatest power of
- * two which is an even divisor of the number of colors,
- * to preserve even coloring of pages.
- */
- if (ncolors & (ncolors - 1) ) {
- int try, picked = 1;
- for (try = 1; try < ncolors; try *= 2) {
- if (ncolors % try == 0) picked = try;
- }
- if (picked == 1) {
- panic("desired number of cache colors %d is "
- " > 1, but not even!", ncolors);
- }
- ncolors = picked;
+ if (tcolors <= ncolors)
+ continue;
+ ncolors = tcolors;
+ }
+
+ /*
+ * If the desired number of colors is not a power of
+ * two, it won't be good. Find the greatest power of
+ * two which is an even divisor of the number of colors,
+ * to preserve even coloring of pages.
+ */
+ if (ncolors & (ncolors - 1) ) {
+ unsigned int try, picked = 1;
+ for (try = 1; try < ncolors; try *= 2) {
+ if (ncolors % try == 0) picked = try;
+ }
+ if (picked == 1) {
+ panic("desired number of cache colors %u is "
+ " > 1, but not even!", ncolors);
}
+ ncolors = picked;
}
/*
