In message <[EMAIL PROTECTED]>, [EMAIL PROTECTED] writes:
>From: Poul-Henning Kamp <[EMAIL PROTECTED]>
>Date: Wed, 27 Sep 2000 15:01:13 +0200
>> >I would like to have review especially on the changes in
>> >i386/isa/clock.c for counting delay loop numbers, 
>> 
>> Could you explain the functionality you need here ?  We already
>> have a DELAY() macro/function in the kernel...
>
>There are codes like;
>        int tout = sc->sc_wc;
>               ;
>        while (slp->sl_scp.scp_datalen > 0 && tout -- > 0)
>        {
>               ;
>       }
>
>To calculate the tout we use;
>        sc->sc_wc = delaycount * 2000;  /* 2 sec */
>
>And we initialize the delaycount in clock.c.

This is called "busy polling" and there must be a better way to do it.

Has this code been profiled to examine typical actual delay lengths ?

--
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
[EMAIL PROTECTED]         | TCP/IP since RFC 956
FreeBSD coreteam member | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.


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