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Altera_Forum
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20 years ago

DSR not called

Dear Forum readers I've been scrathing my head for some time over this. I have a custom board that gives me a periodic interrupt. I've written a ISR- DSR handler pair and they wo...
Altera_Forum's avatar
Altera_Forum
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20 years ago

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originally posted by jskjoet@Dec 3 2005, 09:42 PM

_interrupt_handler enables interrupts after the isr has been called but before posting the dsr (the comments wrongly states that the dsr is called - but it is just added to the list - right ? ).

if we have an interrupt storm this means that each interrupt takes up app 76 bytes on the stack of the thread being interrupted - this might pose a problem.

why not wait and let the eret instruction reenable ints - to prevent eating stack in case of an interrupt storm ?

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Correct me if I'm wrong, but isn't this why the ISR masks its interrupt and the DSR unmasks it? If that same interrupt comes in between ISR and DSR, it has to wait for unmasking, at which point the DSR should be mostly done.