some programs, eg. XAnim or snes9x, still hang for several seconds on my
Dual PentiumPro-180 system for 23s because do_gettimeofday delivers wrong
values. The bug becomes visible when running the program below and a
`find /' at the same time.
My first assumption, my large difference in the TSC registers was wrong, so
I guess this bug should be visible on other Intel SMP systems too, maybe
even UP systems. When this can't be fixed in time, someone should remove the
`do_fast_gettimeoffset' in `linux/arch/i386/kernel/time.c' for 2.2.0, patch
below.
#include <stdio.h>
#include <unistd.h>
#include <syscall.h>
#include <sys/time.h>
struct timeval t;
main()
{
t.tv_sec = 0;
while(1) {
int oldsec = t.tv_sec;
syscall(SYS_gettimeofday, &t, NULL);
if (t.tv_sec<oldsec)
printf("TIME ERROR: %ds\n", oldsec-t.tv_sec);
}
}
Bye,
Mark
--- linux/arch/i386/kernel/time.c.old Fri Jan 22 10:27:19 1999
+++ linux/arch/i386/kernel/time.c Fri Jan 22 11:05:04 1999
@@ -653,7 +653,8 @@
*/
dodgy_tsc();
-
+
+#if 0
if (boot_cpu_data.x86_capability & X86_FEATURE_TSC) {
#ifndef do_gettimeoffset
do_gettimeoffset = do_fast_gettimeoffset;
@@ -674,6 +675,7 @@
printk("Detected %ld Hz processor.\n", cpu_hz);
}
}
+#endif
#ifdef CONFIG_VISWS
printk("Starting Cobalt Timer system clock\n");
-
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