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-rw-r--r--kernel/irq/manage.c52
1 files changed, 49 insertions, 3 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 1753486b440c..3089a60ea8f9 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -18,6 +18,7 @@
#include <linux/sched.h>
#include <linux/sched/rt.h>
#include <linux/sched/task.h>
+#include <linux/sched/isolation.h>
#include <uapi/linux/sched/types.h>
#include <linux/task_work.h>
@@ -217,7 +218,45 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
if (!chip || !chip->irq_set_affinity)
return -EINVAL;
- ret = chip->irq_set_affinity(data, mask, force);
+ /*
+ * If this is a managed interrupt and housekeeping is enabled on
+ * it check whether the requested affinity mask intersects with
+ * a housekeeping CPU. If so, then remove the isolated CPUs from
+ * the mask and just keep the housekeeping CPU(s). This prevents
+ * the affinity setter from routing the interrupt to an isolated
+ * CPU to avoid that I/O submitted from a housekeeping CPU causes
+ * interrupts on an isolated one.
+ *
+ * If the masks do not intersect or include online CPU(s) then
+ * keep the requested mask. The isolated target CPUs are only
+ * receiving interrupts when the I/O operation was submitted
+ * directly from them.
+ *
+ * If all housekeeping CPUs in the affinity mask are offline, the
+ * interrupt will be migrated by the CPU hotplug code once a
+ * housekeeping CPU which belongs to the affinity mask comes
+ * online.
+ */
+ if (irqd_affinity_is_managed(data) &&
+ housekeeping_enabled(HK_FLAG_MANAGED_IRQ)) {
+ const struct cpumask *hk_mask, *prog_mask;
+
+ static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
+ static struct cpumask tmp_mask;
+
+ hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
+
+ raw_spin_lock(&tmp_mask_lock);
+ cpumask_and(&tmp_mask, mask, hk_mask);
+ if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
+ prog_mask = mask;
+ else
+ prog_mask = &tmp_mask;
+ ret = chip->irq_set_affinity(data, prog_mask, force);
+ raw_spin_unlock(&tmp_mask_lock);
+ } else {
+ ret = chip->irq_set_affinity(data, mask, force);
+ }
switch (ret) {
case IRQ_SET_MASK_OK:
case IRQ_SET_MASK_OK_DONE:
@@ -692,6 +731,13 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on)
*
* Wakeup mode lets this IRQ wake the system from sleep
* states like "suspend to RAM".
+ *
+ * Note: irq enable/disable state is completely orthogonal
+ * to the enable/disable state of irq wake. An irq can be
+ * disabled with disable_irq() and still wake the system as
+ * long as the irq has wake enabled. If this does not hold,
+ * then the underlying irq chip and the related driver need
+ * to be investigated.
*/
int irq_set_irq_wake(unsigned int irq, unsigned int on)
{
@@ -1500,8 +1546,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
* has. The type flags are unreliable as the
* underlying chip implementation can override them.
*/
- pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
- irq);
+ pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
+ new->name, irq);
ret = -EINVAL;
goto out_unlock;
}