Re: [PATCH v2 14/15] xen/asm-generic: introduce stub header numa.h

[Jan Beulich <jbeulich@xxxxxxxx>]

On 10.11.2023 17:30, Oleksii Kurochko wrote:
> --- /dev/null
> +++ b/xen/include/asm-generic/numa.h
> @@ -0,0 +1,40 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +#ifndef __ARCH_GENERIC_NUMA_H
> +#define __ARCH_GENERIC_NUMA_H
> +
> +#include <xen/types.h>
> +#include <xen/mm.h>

I'm afraid I can't spot what you need these for here. You clearly need
xen/stdint.h, and you need xen/mm-frame.h for mfn_t. Yes, max_page is
declared in xen/mm.h, but its questionable whether the header needs
including here for that reason, as all uses are in macros. (We aren't
anywhere near consistent in this regard). Plus you don't also include
xen/cpumask.h to pull in cpu_online_map (which another macro
references).

> +typedef uint8_t nodeid_t;
> +
> +#ifndef CONFIG_NUMA

Isn't it an error to include this header when NUMA=y?

> +/* Fake one node for now. See also node_online_map. */
> +#define cpu_to_node(cpu) 0
> +#define node_to_cpumask(node)   (cpu_online_map)
> +
> +/*
> + * TODO: make first_valid_mfn static when NUMA is supported on Arm, this
> + * is required because the dummy helpers are using it.
> + */
> +extern mfn_t first_valid_mfn;
> +
> +/* XXX: implement NUMA support */
> +#define node_spanned_pages(nid) (max_page - mfn_x(first_valid_mfn))
> +#define node_start_pfn(nid) (mfn_x(first_valid_mfn))
> +#define __node_distance(a, b) (20)
> +
> +#endif
> +
> +#define arch_want_default_dmazone() (false)
> +
> +#endif /* __ARCH_GENERIC_NUMA_H */
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * indent-tabs-mode: nil
> + * End:
> + */