> What is the current wisdom on SA_INTERRUPT?
>
> A comment in signal.h about it says "dummy -- ignored". Elsewhere it says
> that "SA_INTERRUPT is a no-op left for historical reasons".
>
> That certainly doesn't seem to be the case in irq.c. It appears to be used
> like this: if SA_INTERRUPT isn't set, enable interrupts during interrupt
> handling.
>
> So what is this flag for? How, when, and why should it be used?
>
> Thanks.
>
> Regards,
> Brad
It is unfortunate that the same #define is used for signals and
for kernel interrupts. They are not related. As you noticed,i
SA_INTERRUPT with respect to signals is a no-op since it doesn't change
the nature of signals. However, with respect to IRQ handling within the
kernel, it does enable interrupts before your possible bottom-half ISR
is checked to see if it exists and executed.
See line 726 (about) in ../arch/i386/kernel/irq.c
Cheers,
Dick Johnson
**** FILE SYSTEM WAS MODIFIED ****
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