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From: uzun@pnet01.cts.com (Roger Uzun)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Micro Timing Critical sections HELP!
Message-ID: <4559@crash.cts.com>
Date: 21 Sep 90 17:56:04 GMT
Sender: root@crash.cts.com
Organization: People-Net [pnet01], El Cajon CA
Lines: 19

>> Dave haynie writes that an application need never use Disable()/Enable()
Actually this is not true.  When I wrote a interrupt handler to strip
off mousevents from the input.device queue, I was "pruning" the linked
list of events streaming in, (using the IND_ADDHANDLER function of
the input.device).  I found that if MASSIVE joystick twitching occurred
while pruning this linked list of events, the linked list pruning
could be interrupted in a critical section of removing one of the
port 1 (mouseport) events, and this caused a system crash (only
when doing 6 bitplane anims with all sprites enabled, when I
had 5 bitplane anims with no sprites enabled, I could not get
it to crash).  To get around this I had to replace
the the Disable/Enable sequence in the int handler with a forbid/permit
sequence, then no crashes were possible.

-Roger

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