From 9821d8d4628e630ab56f47a8e6b878a2576e069b Mon Sep 17 00:00:00 2001 From: Eli Cohen Date: Tue, 14 Feb 2023 09:29:46 +0200 Subject: lib: cpu_rmap: Use allocator for rmap entries Use a proper allocator for rmap entries using a naive for loop. The allocator relies on whether an entry is NULL to be considered free. Remove the used field of rmap which is not needed. Also, avoid crashing the kernel if an entry is not available. Cc: Thomas Gleixner Signed-off-by: Eli Cohen Signed-off-by: Saeed Mahameed Reviewed-by: Jacob Keller --- include/linux/cpu_rmap.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/linux/cpu_rmap.h') diff --git a/include/linux/cpu_rmap.h b/include/linux/cpu_rmap.h index be8aea04d023..0ec745e6cd36 100644 --- a/include/linux/cpu_rmap.h +++ b/include/linux/cpu_rmap.h @@ -16,14 +16,13 @@ * struct cpu_rmap - CPU affinity reverse-map * @refcount: kref for object * @size: Number of objects to be reverse-mapped - * @used: Number of objects added * @obj: Pointer to array of object pointers * @near: For each CPU, the index and distance to the nearest object, * based on affinity masks */ struct cpu_rmap { struct kref refcount; - u16 size, used; + u16 size; void **obj; struct { u16 index; -- cgit From 71f0a2478605c100358a9f9e174849fa643bf8a7 Mon Sep 17 00:00:00 2001 From: Eli Cohen Date: Tue, 14 Feb 2023 11:05:46 +0200 Subject: lib: cpu_rmap: Add irq_cpu_rmap_remove to complement irq_cpu_rmap_add Add a function to complement irq_cpu_rmap_add(). It removes the irq from the reverse mapping by setting the notifier to NULL. The function calls irq_set_affinity_notifier() with NULL at the notify argument which then cancel any pending notifier work and decrement reference on the notifier. When ref count reaches zero, the glue pointer is kfree and the rmap entry is set to NULL serving both to avoid second attempt to release it and also making the rmap entry available for subsequent mapping. It should be noted the drivers usually creates the reverse mapping at initialization time and remove it at unload time so we do not expect failures in allocating rmap due to kref holding the glue entry. Cc: Thomas Gleixner Signed-off-by: Eli Cohen Signed-off-by: Saeed Mahameed Reviewed-by: Jacob Keller --- include/linux/cpu_rmap.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/cpu_rmap.h') diff --git a/include/linux/cpu_rmap.h b/include/linux/cpu_rmap.h index 0ec745e6cd36..cae324d10965 100644 --- a/include/linux/cpu_rmap.h +++ b/include/linux/cpu_rmap.h @@ -60,6 +60,7 @@ static inline struct cpu_rmap *alloc_irq_cpu_rmap(unsigned int size) } extern void free_irq_cpu_rmap(struct cpu_rmap *rmap); +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 */ -- cgit