aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/irq.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-12-05 15:31:25 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-12-05 15:31:25 -0800
commita77d2e081bbbccb38f42da45500dd089756efdfb (patch)
tree8bb8d91e1c9e59143afcac8ff7d74341f7a0af80 /arch/x86/kernel/irq.c
parent897e81bea1fcfcd2c5cdb720c9efdb25da9ff374 (diff)
parent7d1849aff6687a135a8da3a75e32a00e3137a5e2 (diff)
Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (30 commits) x86, apic: Enable lapic nmi watchdog on AMD Family 11h x86: Remove unnecessary mdelay() from cpu_disable_common() x86, ioapic: Document another case when level irq is seen as an edge x86, ioapic: Fix the EOI register detection mechanism x86, io-apic: Move the effort of clearing remoteIRR explicitly before migrating the irq x86: SGI UV: Map low MMR ranges x86: apic: Print out SRAT table APIC id in hex x86: Re-get cfg_new in case reuse/move irq_desc x86: apic: Remove not needed #ifdef x86: io-apic: IO-APIC MMIO should not fail on resource insertion x86: Remove asm/apicnum.h x86: apic: Do not use stacked physid_mask_t x86, apic: Get rid of apicid_to_cpu_present assign on 64-bit x86, ioapic: Use snrpintf while set names for IO-APIC resourses x86, apic: Use PAGE_SIZE instead of numbers x86: Remove local_irq_enable()/local_irq_disable() in fixup_irqs() x86: Use EOI register in io-apic on intel platforms x86: Force irq complete move during cpu offline x86: Remove move_cleanup_count from irq_cfg x86, intr-remap: Avoid irq_chip mask/unmask in fixup_irqs() for intr-remapping ...
Diffstat (limited to 'arch/x86/kernel/irq.c')
-rw-r--r--arch/x86/kernel/irq.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 19212cb0155..fee6cc2b207 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -274,3 +274,93 @@ void smp_generic_interrupt(struct pt_regs *regs)
}
EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
+
+#ifdef CONFIG_HOTPLUG_CPU
+/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
+void fixup_irqs(void)
+{
+ unsigned int irq, vector;
+ static int warned;
+ struct irq_desc *desc;
+
+ for_each_irq_desc(irq, desc) {
+ int break_affinity = 0;
+ int set_affinity = 1;
+ const struct cpumask *affinity;
+
+ if (!desc)
+ continue;
+ if (irq == 2)
+ continue;
+
+ /* interrupt's are disabled at this point */
+ spin_lock(&desc->lock);
+
+ affinity = desc->affinity;
+ if (!irq_has_action(irq) ||
+ cpumask_equal(affinity, cpu_online_mask)) {
+ spin_unlock(&desc->lock);
+ continue;
+ }
+
+ /*
+ * Complete the irq move. This cpu is going down and for
+ * non intr-remapping case, we can't wait till this interrupt
+ * arrives at this cpu before completing the irq move.
+ */
+ irq_force_complete_move(irq);
+
+ if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
+ break_affinity = 1;
+ affinity = cpu_all_mask;
+ }
+
+ if (!(desc->status & IRQ_MOVE_PCNTXT) && desc->chip->mask)
+ desc->chip->mask(irq);
+
+ if (desc->chip->set_affinity)
+ desc->chip->set_affinity(irq, affinity);
+ else if (!(warned++))
+ set_affinity = 0;
+
+ if (!(desc->status & IRQ_MOVE_PCNTXT) && desc->chip->unmask)
+ desc->chip->unmask(irq);
+
+ spin_unlock(&desc->lock);
+
+ if (break_affinity && set_affinity)
+ printk("Broke affinity for irq %i\n", irq);
+ else if (!set_affinity)
+ printk("Cannot set affinity for irq %i\n", irq);
+ }
+
+ /*
+ * We can remove mdelay() and then send spuriuous interrupts to
+ * new cpu targets for all the irqs that were handled previously by
+ * this cpu. While it works, I have seen spurious interrupt messages
+ * (nothing wrong but still...).
+ *
+ * So for now, retain mdelay(1) and check the IRR and then send those
+ * interrupts to new targets as this cpu is already offlined...
+ */
+ mdelay(1);
+
+ for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
+ unsigned int irr;
+
+ if (__get_cpu_var(vector_irq)[vector] < 0)
+ continue;
+
+ irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
+ if (irr & (1 << (vector % 32))) {
+ irq = __get_cpu_var(vector_irq)[vector];
+
+ desc = irq_to_desc(irq);
+ spin_lock(&desc->lock);
+ if (desc->chip->retrigger)
+ desc->chip->retrigger(irq);
+ spin_unlock(&desc->lock);
+ }
+ }
+}
+#endif