lguest: allow any process to send interrupts
We currently only allow the Launcher process to send interrupts, but it
as we already send interrupts from the hrtimer, it's a simple matter of
extracting that code into a common set_interrupt routine.
As we switch to a thread per virtqueue, this avoids a bottleneck through the
main Launcher process.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c
index 5a10754..0e9067b 100644
--- a/drivers/lguest/interrupts_and_traps.c
+++ b/drivers/lguest/interrupts_and_traps.c
@@ -213,6 +213,20 @@
if (!more)
put_user(0, &cpu->lg->lguest_data->irq_pending);
}
+
+/* And this is the routine when we want to set an interrupt for the Guest. */
+void set_interrupt(struct lg_cpu *cpu, unsigned int irq)
+{
+ /* Next time the Guest runs, the core code will see if it can deliver
+ * this interrupt. */
+ set_bit(irq, cpu->irqs_pending);
+
+ /* Make sure it sees it; it might be asleep (eg. halted), or
+ * running the Guest right now, in which case kick_process()
+ * will knock it out. */
+ if (!wake_up_process(cpu->tsk))
+ kick_process(cpu->tsk);
+}
/*:*/
/* Linux uses trap 128 for system calls. Plan9 uses 64, and Ron Minnich sent
@@ -528,10 +542,7 @@
struct lg_cpu *cpu = container_of(timer, struct lg_cpu, hrt);
/* Remember the first interrupt is the timer interrupt. */
- set_bit(0, cpu->irqs_pending);
- /* Guest may be stopped or running on another CPU. */
- if (!wake_up_process(cpu->tsk))
- kick_process(cpu->tsk);
+ set_interrupt(cpu, 0);
return HRTIMER_NORESTART;
}