Subject: [PATCH net-next 03/14] lib: cpu_rmap: Add irq_cpu_rmap_remove to complement irq_cpu_rmap_add

From: Saeed Mahameed <[email-masked]>
Date: Sun, 19 Feb 2023 22:14:31 -0800

From: Eli Cohen <[email-masked]>

Add a function to complement irq_cpu_rmap_add(). It removes the irq from
the reverse mapping by setting the notifier to NULL.

CC: Ben Hutchings <[email-masked]>
CC: Andrew Morton <[email-masked]>
CC: David Decotigny <[email-masked]>
CC: Eric Dumazet <[email-masked]>
CC: [email-masked]
Signed-off-by: Eli Cohen <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 include/linux/cpu_rmap.h |  2 ++
 lib/cpu_rmap.c           | 11 +++++++++++
 2 files changed, 13 insertions(+)

diff --git a/include/linux/cpu_rmap.h b/include/linux/cpu_rmap.h
index 0ec745e6cd36..58284f1f3a58 100644
--- a/include/linux/cpu_rmap.h
+++ b/include/linux/cpu_rmap.h
@@ -60,6 +60,8 @@ static inline struct cpu_rmap *alloc_irq_cpu_rmap(unsigned int size)
 }
 extern void free_irq_cpu_rmap(struct cpu_rmap *rmap);
 
+extern int irq_cpu_rmap_remove(struct cpu_rmap *rmap, int irq);
 extern int irq_cpu_rmap_add(struct cpu_rmap *rmap, int irq);
 
+
 #endif /* __LINUX_CPU_RMAP_H */
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c
index e95d018e01c2..7c67e9382845 100644
--- a/lib/cpu_rmap.c
+++ b/lib/cpu_rmap.c
@@ -285,6 +285,17 @@ static void irq_cpu_rmap_release(struct kref *ref)
 	kfree(glue);
 }
 
+/**
+ * irq_cpu_rmap_remove - remove an IRQ from a CPU affinity reverse-map
+ * @rmap: The reverse-map
+ * @irq: The IRQ number
+ */
+int irq_cpu_rmap_remove(struct cpu_rmap *rmap, int irq)
+{
+	return irq_set_affinity_notifier(irq, NULL);
+}
+EXPORT_SYMBOL(irq_cpu_rmap_remove);
+
 /**
  * irq_cpu_rmap_add - add an IRQ to a CPU affinity reverse-map
  * @rmap: The reverse-map
-- 
2.39.1