Commit-ID: cbf8699996a6e7f2f674b3a2a4cef9f666ff613e
Gitweb: https://git.kernel.org/tip/cbf8699996a6e7f2f674b3a2a4cef9f666ff613e
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Fri, 16 Feb 2018 15:21:20 +0100
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Fri, 16 Feb 2018 15:28:50 +0100
genirq: Let irq thread follow the effective hard irq affinity
In case of threaded interrupts the thread follows the affinity setting of
the hard interrupt. The related function uses the affinity mask which was
set by either from user space or via one of the kernel mechanisms. This
mask can be wider than the resulting effective affinity of the hard
interrupt. As a consequence the thread might become affine to a completely
different CPU.
Use the effective interrupt affinity if the architecture supports it, so
the hard interrupt and the thread stay on the same CPU.
Reported-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Tested-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
kernel/irq/manage.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 0f92272..d2b3c59 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -855,10 +855,14 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
* This code is triggered unconditionally. Check the affinity
* mask pointer. For CPU_MASK_OFFSTACK=n this is optimized out.
*/
- if (cpumask_available(desc->irq_common_data.affinity))
- cpumask_copy(mask, desc->irq_common_data.affinity);
- else
+ if (cpumask_available(desc->irq_common_data.affinity)) {
+ const struct cpumask *m;
+
+ m = irq_data_get_effective_affinity_mask(&desc->irq_data);
+ cpumask_copy(mask, m);
+ } else {
valid = false;
+ }
raw_spin_unlock_irq(&desc->lock);
if (valid)
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|