On Fri, 2006-09-08 at 11:25 +0100, David Howells wrote: > Benjamin Herrenschmidt <[EMAIL PROTECTED]> wrote: > > > No, you do a chain handler. Look at how I do it in > > arch/powerpc/platform/pseries/setup.c for example. It's actually > > trivial. You install a special flow handler (which means that there is > > very little overhead, almost none, from the toplevel irq to the chained > > irq). You can _also_ if you want just install an IRQ handler for the > > cascaded controller and call generic_handle_irq (rather than __do_IRQ) > > from it, but that has more overhead. A chained handler completely > > relaces the flow handler for the cascade, and thus, if you don't need > > all of the nits and bits of the other flow handlers for your cascade, > > you can speed things up by hooking at that level. > > Please update Documentation/DocBook/genericirq.tmpl. That doesn't mention it.
I must admit I haven't read the documentation :) I looked at the code/patches when genirq was posted and did my powerpc implementation based on my understanding of the code and discussions with Thomas and Ingo. I'll have a look at the doc next week and see if I can improve it. Cheers, Ben. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
