[PATCH v13 3/6] of, numa: Add NUMA of binding implementation.
Rob Herring
robh+dt at kernel.org
Wed Mar 2 19:34:37 PST 2016
On Wed, Mar 2, 2016 at 4:55 PM, David Daney <ddaney.cavm at gmail.com> wrote:
> From: David Daney <david.daney at cavium.com>
>
> Add device tree parsing for NUMA topology using device
> "numa-node-id" property in distance-map and cpu nodes.
>
> This is a complete rewrite of a previous patch by:
> Ganapatrao Kulkarni<gkulkarni at caviumnetworks.com>
>
> Signed-off-by: David Daney <david.daney at cavium.com>
> ---
> drivers/of/Kconfig | 3 +
> drivers/of/Makefile | 1 +
> drivers/of/of_numa.c | 200 +++++++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/of.h | 9 +++
> 4 files changed, 213 insertions(+)
> create mode 100644 drivers/of/of_numa.c
>
> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
> index e2a4841..b3bec3a 100644
> --- a/drivers/of/Kconfig
> +++ b/drivers/of/Kconfig
> @@ -112,4 +112,7 @@ config OF_OVERLAY
> While this option is selected automatically when needed, you can
> enable it manually to improve device tree unit test coverage.
>
> +config OF_NUMA
> + bool
> +
> endif # OF
> diff --git a/drivers/of/Makefile b/drivers/of/Makefile
> index 156c072..bee3fa9 100644
> --- a/drivers/of/Makefile
> +++ b/drivers/of/Makefile
> @@ -14,5 +14,6 @@ obj-$(CONFIG_OF_MTD) += of_mtd.o
> obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
> obj-$(CONFIG_OF_RESOLVE) += resolver.o
> obj-$(CONFIG_OF_OVERLAY) += overlay.o
> +obj-$(CONFIG_OF_NUMA) += of_numa.o
>
> obj-$(CONFIG_OF_UNITTEST) += unittest-data/
> diff --git a/drivers/of/of_numa.c b/drivers/of/of_numa.c
> new file mode 100644
> index 0000000..9727b60
> --- /dev/null
> +++ b/drivers/of/of_numa.c
> @@ -0,0 +1,200 @@
> +/*
> + * OF NUMA Parsing support.
> + *
> + * Copyright (C) 2015 - 2016 Cavium Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/of.h>
> +#include <linux/of_fdt.h>
This can be dropped now.
> +#include <linux/nodemask.h>
> +
> +#include <asm/numa.h>
> +
> +/* define default numa node to 0 */
> +#define DEFAULT_NODE 0
> +
> +/*
> + * Even though we connect cpus to numa domains later in SMP
> + * init, we need to know the node ids now for all cpus.
> +*/
> +static void __init of_find_cpu_nodes(void)
Perhaps of_parse_cpu_nodes for consistency.
Actually, if all the functions were prefixed with "of_numa_" that
would be better.
> +{
> + u32 nid;
> + int r;
> + struct device_node *np = NULL;
> +
> + for (;;) {
> + np = of_find_node_by_type(np, "cpu");
> + if (!np)
> + break;
Can't we use the child node iterator for /cpus here?
> +
> + r = of_property_read_u32(np, "numa-node-id", &nid);
> + if (r)
> + continue;
> +
> + pr_debug("NUMA: CPU on %u\n", nid);
> + if (nid >= MAX_NUMNODES)
> + pr_warn("NUMA: Node id %u exceeds maximum value\n",
> + nid);
> + else
> + node_set(nid, numa_nodes_parsed);
I'm not sure how this works, but don't you need to match this up with
MPIDR of the cpu here?
> + }
> +}
> +
> +static void __init of_parse_memory_nodes(void)
> +{
> + struct device_node *np = NULL;
> + int na, ns;
> + const __be32 *prop;
> + unsigned int psize;
> + u32 nid;
> + u64 base, size;
> + int r;
> +
> + for (;;) {
> + np = of_find_node_by_type(np, "memory");
> + if (!np)
> + break;
> +
> + r = of_property_read_u32(np, "numa-node-id", &nid);
> + if (r)
> + continue;
> +
> + prop = of_get_property(np, "reg", &psize);
> + if (!prop)
> + continue;
> +
> + psize /= sizeof(__be32);
> + na = of_n_addr_cells(np);
> + ns = of_n_size_cells(np);
> +
> + if (psize < na + ns) {
> + pr_err("NUMA: memory reg property too small\n");
> + continue;
> + }
> + base = of_read_number(prop, na);
> + size = of_read_number(prop + na, ns);
You should be able to use of_address_to_resource for all this.
> +
> + pr_debug("NUMA: base = %llx len = %llx, node = %u\n",
> + base, size, nid);
> +
> + if (numa_add_memblk(nid, base, size) < 0)
> + break;
> + }
> +
> + of_node_put(np);
> +}
> +
> +static int __init parse_distance_map_v1(struct device_node *map)
> +{
> + const __be32 *matrix;
> + unsigned int matrix_size;
> + int entry_count;
> + int i;
> + int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
I believe the defaults are for some old DT files. As this is new, it
should rely on explicit #size-cells in the DT.
OTOH, what is point of using #size-cells at all versus fixing the
sizes to 1 cell. The documentation doesn't indicate that it uses
#size-cells. That also means that the sizes basically follow the cell
size for the memory given that this is at the top-level.
> +
> + pr_info("NUMA: parsing numa-distance-map-v1\n");
> +
> + matrix = of_get_property(map, "distance-matrix", &matrix_size);
> + if (!matrix) {
> + pr_err("NUMA: No distance-matrix property in distance-map\n");
> + return -EINVAL;
> + }
> +
> + entry_count = matrix_size / (sizeof(__be32) * 3 * nr_size_cells);
> +
> + for (i = 0; i < entry_count; i++) {
> + u32 nodea, nodeb, distance;
> +
> + nodea = of_read_number(matrix, nr_size_cells);
> + matrix += nr_size_cells;
> + nodeb = of_read_number(matrix, nr_size_cells);
> + matrix += nr_size_cells;
> + distance = of_read_number(matrix, nr_size_cells);
> + matrix += nr_size_cells;
Assuming you fix this to 1 cell, you can use
of_property_count_u32_elems and of_property_read_u32_array.
> +
> + numa_set_distance(nodea, nodeb, distance);
> + pr_debug("NUMA: distance[node%d -> node%d] = %d\n",
> + nodea, nodeb, distance);
> +
> + /* Set default distance of node B->A same as A->B */
> + if (nodeb > nodea)
> + numa_set_distance(nodeb, nodea, distance);
> + }
> +
> + return 0;
> +}
> +
> +static int __init of_parse_distance_map(void)
> +{
> + int ret = -EINVAL;
> + struct device_node *np = of_find_node_by_name(NULL, "distance-map");
> +
> + if (!np)
> + return ret;
> +
> + if (of_device_is_compatible(np, "numa-distance-map-v1")) {
You can use of_find_compatible_node() instead of these 2 calls.
> + ret = parse_distance_map_v1(np);
> + goto out;
> + }
> +
> + pr_err("NUMA: invalid distance-map device node\n");
> +out:
> + of_node_put(np);
> + return ret;
> +}
> +
> +int of_node_to_nid(struct device_node *device)
> +{
> + struct device_node *np;
> + u32 nid;
> + int r = -ENODATA;
> +
> + np = of_node_get(device);
> +
> + while (np) {
> + struct device_node *parent;
> +
> + r = of_property_read_u32(np, "numa-node-id", &nid);
> + if (r != -EINVAL)
You want to break for other err values?
> + break;
> +
> + /* property doesn't exist in this node, look in parent */
> + parent = of_get_parent(np);
> + of_node_put(np);
> + np = parent;
> + }
> + if (np && r)
> + pr_warn("NUMA: Invalid \"numa-node-id\" property in node %s\n",
> + np->name);
> + of_node_put(np);
> +
> + if (!r) {
> + if (nid >= MAX_NUMNODES)
> + pr_warn("NUMA: Node id %u exceeds maximum value\n",
> + nid);
> + else
> + return nid;
> + }
> +
> + return NUMA_NO_NODE;
> +}
Needs to be exported?
> +
> +int __init of_numa_init(void)
> +{
> + of_find_cpu_nodes();
> + of_parse_memory_nodes();
> + return of_parse_distance_map();
> +}
> diff --git a/include/linux/of.h b/include/linux/of.h
> index dc6e396..fe67a4c 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -685,6 +685,15 @@ static inline int of_node_to_nid(struct device_node *device)
> }
> #endif
>
> +#ifdef CONFIG_OF_NUMA
> +extern int of_numa_init(void);
> +#else
> +static inline int of_numa_init(void)
> +{
> + return -ENOSYS;
> +}
> +#endif
> +
> static inline struct device_node *of_find_matching_node(
> struct device_node *from,
> const struct of_device_id *matches)
> --
> 1.8.3.1
>
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