[patch 11/26] x64, x2apic/intr-remap: generic irq migration support from process context

[Suresh Siddha]

Generic infrastructure for migrating the irq from the process context in the
presence of CONFIG_GENERIC_PENDING_IRQ.

This will be used later for migrating irq in the presence of
interrupt-remapping.

Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
---

Index: tree-x86/include/linux/irq.h
===================================================================
--- tree-x86.orig/include/linux/irq.h	2008-07-10 09:51:45.000000000 -0700
+++ tree-x86/include/linux/irq.h	2008-07-10 09:52:07.000000000 -0700
@@ -62,6 +62,7 @@
 #define IRQ_MOVE_PENDING	0x00200000	/* need to re-target IRQ destination */
 #define IRQ_NO_BALANCING	0x00400000	/* IRQ is excluded from balancing */
 #define IRQ_SPURIOUS_DISABLED	0x00800000	/* IRQ was disabled by the spurious trap */
+#define IRQ_MOVE_PCNTXT	0x01000000	/* IRQ migration from process context */
 
 #ifdef CONFIG_IRQ_PER_CPU
 # define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
Index: tree-x86/kernel/irq/manage.c
===================================================================
--- tree-x86.orig/kernel/irq/manage.c	2008-07-10 09:51:45.000000000 -0700
+++ tree-x86/kernel/irq/manage.c	2008-07-10 09:52:07.000000000 -0700
@@ -89,7 +89,14 @@
 	set_balance_irq_affinity(irq, cpumask);
 
 #ifdef CONFIG_GENERIC_PENDING_IRQ
-	set_pending_irq(irq, cpumask);
+	if (desc->status & IRQ_MOVE_PCNTXT) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&desc->lock, flags);
+		desc->chip->set_affinity(irq, cpumask);
+		spin_unlock_irqrestore(&desc->lock, flags);
+	} else
+		set_pending_irq(irq, cpumask);
 #else
 	desc->affinity = cpumask;
 	desc->chip->set_affinity(irq, cpumask);

-- 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" 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.tux.org/lkml/