[Lguest] [PATCH RFC/RFB] x86_64, i386: interrupt dispatch changes

[Alexander van Heukelum]

On Tue, 4 Nov 2008 17:54:09 +0100, "Ingo Molnar" <mingo at elte.hu> said:
> 
> * Alexander van Heukelum <heukelum at fastmail.fm> wrote:
> 
> > > My estimation is that if we do it right, your approach will behave 
> > > better on modern CPUs (which is what matters most for such 
> > > things), especially on real workloads where there's a considerable 
> > > instruction-cache pressure. But it should be measured in any case.
> > 
> > Fully agreed. I will do some measurements in the near future, maybe 
> > next week. At least noone came up with an absolutely blocking 
> > problem with this approach ;).
> 
> how about "it does not build with lguest enabled" as a blocking 
> problem? ;-)
> 
>   arch/x86/lguest/built-in.o: In function `lguest_init_IRQ':
>   boot.c:(.init.text+0x33f): undefined reference to `interrupt'

The following makes it compile... Whether it works is a different
question ;).

index a5d8e1a..ad7e292 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -580,6 +580,7 @@ static struct irq_chip lguest_irq_controller = {
  * interrupt (except 128, which is used for system calls), and then
  tells the
  * Linux infrastructure that each interrupt is controlled by our
  level-based
  * lguest interrupt controller. */
+void maininterrupt(void);
 static void __init lguest_init_IRQ(void)
 {
        unsigned int i;
@@ -590,7 +591,7 @@ static void __init lguest_init_IRQ(void)
                 * a straightforward 1 to 1 mapping, so force that here.
                 */
                __get_cpu_var(vector_irq)[vector] = i;
                if (vector != SYSCALL_VECTOR) {
-                       set_intr_gate(vector, interrupt[vector]);
+                       set_intr_gate(vector, maininterrupt);
                        set_irq_chip_and_handler_name(i,
                        &lguest_irq_controller,
                                                      handle_level_irq,
                                                      "level");

> config attached.
> 
> 	Ingo
-- 
  Alexander van Heukelum
  heukelum at fastmail.fm

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