Messages in this thread | | | Date | Tue, 05 Nov 2002 08:54:28 -0800 | From | george anzinger <> | Subject | Re: [PATCH] Re: time() glitch on 2.4.18: solved |
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Jim Paris wrote: > > > > Any comments? > > > > Have a play with it, if your idea works when you deliberately disturb it > > then send in a patch > > This works well.
But it does introduce a hiccup in time. One could just do an odd read IF that is all that is wrong. Your code could also be correcting for other ills...
-g > > -jim > > diff -urN linux-2.4.18/arch/i386/kernel/time.c linux-2.4.18-jim/arch/i386/kernel/time.c > --- linux-2.4.18/arch/i386/kernel/time.c Fri Mar 15 18:28:53 2002 > +++ linux-2.4.18-jim/arch/i386/kernel/time.c Tue Nov 5 11:22:02 2002 > @@ -501,6 +501,16 @@ > > count = inb_p(0x40); /* read the latched count */ > count |= inb(0x40) << 8; > + > + /* Any unpaired read will cause the above to swap MSB/LSB > + forever. Try to detect this and reset the counter. */ > + if (count > LATCH) { > + outb_p(0x34, 0x43); > + outb_p(LATCH & 0xff, 0x40); > + outb(LATCH >> 8, 0x40); > + count = LATCH - 1; > + } > + > spin_unlock(&i8253_lock); > > count = ((LATCH-1) - count) * TICK_SIZE; > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
-- George Anzinger george@mvista.com High-res-timers: http://sourceforge.net/projects/high-res-timers/ Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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