[PATCH v8 10/16] mm/memblock: add a new function memblock_alloc_near_nid

Leizhen (ThunderTown) thunder.leizhen at huawei.com
Thu Sep 8 20:49:43 PDT 2016


Hi, linux-mm folks:
    Can somebody help me to review this patch?
    I ran scripts/get_maintainer.pl -f mm/memblock.c and scripts/get_maintainer.pl -f mm/, but
the results showed me that there is no maintainer.
    To understand this patch should also read patch 11.

On 2016/9/1 14:55, Zhen Lei wrote:
> If HAVE_MEMORYLESS_NODES is selected, and some memoryless numa nodes are
> actually exist. The percpu variable areas and numa control blocks of that
> memoryless numa nodes must be allocated from the nearest available node
> to improve performance.
> 
> Signed-off-by: Zhen Lei <thunder.leizhen at huawei.com>
> ---
>  include/linux/memblock.h |  1 +
>  mm/memblock.c            | 28 ++++++++++++++++++++++++++++
>  2 files changed, 29 insertions(+)
> 
> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index 2925da2..8e866e0 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -290,6 +290,7 @@ static inline int memblock_get_region_node(const struct memblock_region *r)
> 
>  phys_addr_t memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid);
>  phys_addr_t memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid);
> +phys_addr_t memblock_alloc_near_nid(phys_addr_t size, phys_addr_t align, int nid);
> 
>  phys_addr_t memblock_alloc(phys_addr_t size, phys_addr_t align);
> 
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 483197e..6578fff 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1189,6 +1189,34 @@ again:
>  	return ret;
>  }
> 
> +phys_addr_t __init memblock_alloc_near_nid(phys_addr_t size, phys_addr_t align, int nid)
> +{
> +	int i, best_nid, distance;
> +	u64 pa;
> +	DECLARE_BITMAP(nodes_map, MAX_NUMNODES);
> +
> +	bitmap_zero(nodes_map, MAX_NUMNODES);
> +
> +find_nearest_node:
> +	best_nid = NUMA_NO_NODE;
> +	distance = INT_MAX;
> +
> +	for_each_clear_bit(i, nodes_map, MAX_NUMNODES)
> +		if (node_distance(nid, i) < distance) {
> +			best_nid = i;
> +			distance = node_distance(nid, i);
> +		}
> +
> +	pa = memblock_alloc_nid(size, align, best_nid);
> +	if (!pa) {
> +		BUG_ON(best_nid == NUMA_NO_NODE);
> +		bitmap_set(nodes_map, best_nid, 1);
> +		goto find_nearest_node;
> +	}
> +
> +	return pa;
> +}
> +
>  phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
>  {
>  	return memblock_alloc_base_nid(size, align, max_addr, NUMA_NO_NODE,
> --
> 2.5.0
> 
> 
> 
> .
> 




More information about the linux-arm-kernel mailing list