On Sun, 27 Feb 2000, Boris Okun wrote:
>Before you jump and tell me that processors must be the same let me
>point out that Intel specifically calls for support of processors of
>different abilities and speeds for an OS to be MP Spec 1.4 compliant.
If the processors runs at different clock speed linux won't get it right.
In such a case you'll have to hack time.c along these lines:
--- 2.2.14/arch/i386/kernel/time.c Mon Jan 17 16:44:33 2000
+++ /tmp/time.c Mon Feb 28 00:29:54 2000
@@ -110,7 +110,6 @@
#define TICK_SIZE tick
-#ifndef CONFIG_X86_TSC
/* This function must be called with interrupts disabled
* It was inspired by Steve McCanne's microtime-i386 for BSD. -- jrs
@@ -223,13 +222,7 @@
return count;
}
-static unsigned long (*do_gettimeoffset)(void) = do_slow_gettimeoffset;
-
-#else
-
-#define do_gettimeoffset() do_fast_gettimeoffset()
-
-#endif
+#define do_gettimeoffset() do_slow_gettimeoffset()
/*
* This version of gettimeofday has microsecond resolution
@@ -644,6 +637,7 @@
dodgy_tsc();
+#if 0
if (boot_cpu_data.x86_capability & X86_FEATURE_TSC) {
unsigned long tsc_quotient = calibrate_tsc();
if (tsc_quotient) {
@@ -667,6 +661,7 @@
}
}
}
+#endif
#ifdef CONFIG_VISWS
printk("Starting Cobalt Timer system clock\n");
(the above patch will probably fix your problem anyway even if your
problem is that at least one CPU has a not correctly working TSC)
Andrea
-
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This archive was generated by hypermail 2b29 : Tue Feb 29 2000 - 21:00:18 EST