On 2/7/08, Rick Brown <rick.brown.3@xxxxxxxxx> wrote: > Hi, > > If a particual IRQ line has been disabled (disable_irq()), what > happens if the device on that IRQ line generates interrupt? Does it > result in missed interrupt? Yes, and there are a few other problems with interrupts too. For missed interrupt, we solved by "bottom half". In essence the interrupt handler has to be very short (which is immuned to another interrupt trigger), and complete as soon as possible to get ready to receive another interrupt, while the "deferred context" can execute slowly, but is all the time interrupt-ready. > > And in case of Uniprocessor machine, what happens if interrupts are > generated while spinlock_irq_save() etc? > Same, missed interrupts. Check this out: http://www.cs.utah.edu/classes/cs5785/slides/08-6up.pdf -- To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs
