Re: another must-fix: major PS/2 mouse problem

[Andrew Morton <akpm@osdl.org>]

Albert Cahalan <albert@users.sourceforge.net> wrote:
>
> I hope you don't consider a 100 Mb/s PCI device to be
> a nasty old NIC. It's not an NE2000 you know! I have this:

Sorry, I got my boomerangs and vortices mixed up. Vortex is the ancient one.

> I added code to the top and bottom of do_IRQ, as well as to
> the top and bottom of boomerang_interrupt. The lockmeter was
> compiled into the kernel but never enabled. I record the
> minimum and maximum time in microseconds.
> 
> -------------------------------
> IRQ    num use      min     max
> --- ------ -------- --- -------   
>   0 746770 timer     40  103595
>   1    936 i8042     13  389773
>   2      0 cascade    -       -
>   3      - -          -       -
>   4      9 serial    28      56
>   5      0 uhci-hcd   -       -
>   6      - -        711     711
>   7      - -         25      25
>   8      - -          -       -
>   9      - -          -       -
>  10      - -          -       -
>  11   2417 eth0      87 1535331
>  12     60 i8042     18  102895
>  13      - -          -       -
>  14  13844 ide0       8   51944
>  15      2 ide1       7      11 

But did your instrumentation account for nested interrupts?  What happens
if a slow i8042 interrupt happens in the middle of a 3c59x interrupt?

Still, that probably doesn't account for the stalls.

I don't know what does account for it, frankly.  You could try dropping the
2.4 driver into the 2.5 tree just to verify that it is not a driver
problem.  The driver has hardly changed at all.