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

From: Saeed Mahameed
Date: Mon Feb 20 2023 - 01:17:12 EST


From: Eli Cohen <elic@xxxxxxxxxx>

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 <bhutchings@xxxxxxxxxxxxxx>
CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
CC: David Decotigny <decot@xxxxxxxxxxxx>
CC: Eric Dumazet <edumazet@xxxxxxxxxx>
CC: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
---
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