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

[Rebecca Mckeever <remckee0@gmail.com>]

On Wed, Aug 31, 2022 at 06:15:41PM +0300, Mike Rapoport wrote:
> 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@gmail.com>
> > ---
> >  .../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.
> 
Okay, will do.

> > +{
> > +	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.

Thanks,
Rebecca