At Fri, 27 Nov 2009 11:02:25 +0900, Tejun Heo wrote: > > Hello, > > 11/26/2009 09:40 PM, Andy Walls wrote: > >> * If you need to respond fast, wouldn't you be doing that from IRQ > >> handler or softirq? Do you need task context? > > > > I'm not sure doing things like I2C transactions in the in the top half > > of the IRQ handler is generally viable. On shared IRQ lines, wouldn't > > this hold off the interrupt for another device for too long? > > > > For example, I already ran across the case of an error path in the ahci > > disk controller driver interrupt handler holding off interrupts from the > > cx18 driver longer than the CX23418 firmware would tolerate on a shared > > interrupt line. > > Sounds like it should be using bottom half tasklet not workqueue. > Tasklet is exactly designed to handle situations like this. Is there > any reason tasklet can't be used? Right now the h/w accessing code is using mutex. I'm not sure whether the deeper part might sleep, though... Takashi -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
