[PATCH v1 7/7] [NOT-FOR-MERGE] test managed irqs affinity adjustment

From: Costa Shulyupin
Date: Thu May 16 2024 - 15:14:21 EST


Kernel module to generatemanaged irqs for the test
and shell commands.

Signed-off-by: Costa Shulyupin <costa.shul@xxxxxxxxxx>
---
tests/managed_irq.c | 71 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 71 insertions(+)
create mode 100644 tests/managed_irq.c

diff --git a/tests/managed_irq.c b/tests/managed_irq.c
new file mode 100644
index 0000000000000..fd4e91e44e59d
--- /dev/null
+++ b/tests/managed_irq.c
@@ -0,0 +1,71 @@
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+
+/*
+ * Testing instructions:
+ *
+ * isolate=1
+ * insmod managed_irq.ko test_cpu=$isolate
+ * cd /sys/fs/cgroup/
+ * echo +cpuset > cgroup.subtree_control
+ * mkdir test
+ * echo isolated > test/cpuset.cpus.partition
+ * echo $isolate > test/cpuset.cpus
+ * read test_irq < /sys/module/managed_irq/parameters/test_irq
+ *
+ * cat /proc/irq/$test_irq/smp_affinity_list
+ *
+ * read affinity < /proc/irq/$test_irq/smp_affinity
+ * test 0 -ne $((0x$affinity & 1 << $isolate)) && echo FAIL | PASS
+ *
+ * Assure that irq affinity doesn't contain isolated cpu.
+ */
+
+static int test_cpu = 1;
+module_param(test_cpu, int, 0444);
+
+static int test_irq;
+module_param(test_irq, int, 0444);
+
+static irqreturn_t test_irq_cb(int irq, void *dev_id)
+{
+ return IRQ_HANDLED;
+}
+
+static int test_set_affinity(struct irq_data *d, const struct cpumask *m, bool f)
+{
+ irq_data_update_effective_affinity(d, m);
+ return 0;
+}
+
+static int make_test_irq(void)
+{
+ struct irq_affinity_desc a = {
+ mask: *cpumask_of(test_cpu),
+ is_managed: true
+ };
+ int test_irq = __irq_alloc_descs(-1, 1, 1, 0, THIS_MODULE, &a);
+ static struct irq_chip test_chip = { .irq_set_affinity =
+ test_set_affinity };
+
+ irq_set_chip(test_irq, &test_chip);
+ irq_set_status_flags(test_irq, IRQ_MOVE_PCNTXT);
+ pr_debug("test_irq=%d\n", test_irq);
+ int err = request_irq(test_irq, test_irq_cb, 0, "test_affinity", 0);
+
+ if (err)
+ pr_err("%d\n", err);
+
+ return test_irq;
+}
+
+static int managed_irq_init(void)
+{
+ test_irq = make_test_irq();
+ return 0;
+}
+
+module_init(managed_irq_init);
+
+MODULE_LICENSE("GPL");
--
2.45.0