[PATCH bpf-next 1/4] bpf: tailcall: Introduce bpf_arch_tail_call_prologue_offset

[bot+bpf-ci at kernel.org]

> diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
> index 1eeb31c5b317..beedd1281c22 100644
> --- a/kernel/bpf/arraymap.c
> +++ b/kernel/bpf/arraymap.c
> @@ -127,6 +127,9 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
>  			array_size += (u64) max_entries * elem_size;
>  		}
>  	}
> +	if (attr->map_type == BPF_MAP_TYPE_PROG_ARRAY && bpf_arch_tail_call_prologue_offset())
> +		/* Store tailcall targets */
> +		array_size += (u64) max_entries * sizeof(void *);

Should array_map_mem_usage() also account for this additional space?
Currently array_map_mem_usage() handles special cases for percpu arrays
and mmapable arrays, but has no corresponding check for PROG_ARRAY maps
when bpf_arch_tail_call_prologue_offset() is non-zero. This would cause
the reported memory usage to be lower than the actual allocation when
an architecture implements this function (e.g., x86_64 and arm64 in the
subsequent patches of this series).

[ ... ]


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CI run summary: https://github.com/kernel-patches/bpf/actions/runs/20660615603