Re: [PATCH v2 1/4] memblock tests: add simulation of physical memory with multiple NUMA nodes

From: Mike Rapoport
Date: Wed Aug 31 2022 - 11:16:03 EST


On Fri, Aug 19, 2022 at 02:05:31AM -0700, Rebecca Mckeever wrote:
> Add functions setup_numa_memblock_generic() and setup_numa_memblock()
> for setting up a memory layout with multiple NUMA nodes in a previously
> allocated dummy physical memory. These functions can be used in place of
> setup_memblock() in tests that need to simulate a NUMA system.
>
> setup_numa_memblock_generic():
> - allows for setting up a custom memory layout by specifying the amount
> of memory in each node, the number of nodes, and a factor that will be
> used to scale the memory in each node
>
> setup_numa_memblock():
> - allows for setting up a default memory layout
>
> Introduce constant MEM_FACTOR, which is used to scale the default memory
> layout based on MEM_SIZE.
>
> Set CONFIG_NODES_SHIFT to 4 when building with NUMA=1 to allow for up to
> 16 NUMA nodes.
>
> Signed-off-by: Rebecca Mckeever <remckee0@xxxxxxxxx>
> ---
> .../testing/memblock/scripts/Makefile.include | 2 +-
> tools/testing/memblock/tests/common.c | 38 +++++++++++++++++++
> tools/testing/memblock/tests/common.h | 9 ++++-
> 3 files changed, 47 insertions(+), 2 deletions(-)

...

> +/**
> + * setup_numa_memblock_generic:
> + * Set up a memory layout with multiple NUMA nodes in a previously allocated
> + * dummy physical memory.
> + * @nodes: an array containing the amount of memory in each node
> + * @node_cnt: the size of @nodes
> + * @factor: a factor that will be used to scale the memory in each node
> + *
> + * The nids will be set to 0 through node_cnt - 1.
> + */
> +void setup_numa_memblock_generic(const phys_addr_t nodes[],
> + int node_cnt, int factor)

I only had time for a quick look and it seems this function is never used
on its own.
Let's fold it into setup_numa_memblock() for now.

> +{
> + phys_addr_t base;
> + int flags;
> +
> + reset_memblock_regions();
> + base = (phys_addr_t)memory_block.base;
> + flags = (movable_node_is_enabled()) ? MEMBLOCK_NONE : MEMBLOCK_HOTPLUG;
> +
> + for (int i = 0; i < node_cnt; i++) {
> + phys_addr_t size = factor * nodes[i];
> +
> + memblock_add_node(base, size, i, flags);
> + base += size;
> + }
> + fill_memblock();
> +}
> +
> +void setup_numa_memblock(void)
> +{
> + setup_numa_memblock_generic(node_sizes, NUMA_NODES, MEM_FACTOR);
> +}
> +

--
Sincerely yours,
Mike.