mirror of
https://github.com/torvalds/linux.git
synced 2026-08-07 07:54:18 +02:00
Linux kernel source tree
Introduce the new helper for_each_node_numadist() to iterate over node
IDs in order of increasing NUMA distance from a given starting node.
This iterator is somehow similar to for_each_numa_hop_mask(), but
instead of providing a cpumask at each iteration, it provides a node ID.
Example usage:
nodemask_t unvisited = NODE_MASK_ALL;
int node, start = cpu_to_node(smp_processor_id());
node = start;
for_each_node_numadist(node, unvisited)
pr_info("node (%d, %d) -> %d\n",
start, node, node_distance(start, node));
On a system with equidistant nodes:
$ numactl -H
...
node distances:
node 0 1 2 3
0: 10 20 20 20
1: 20 10 20 20
2: 20 20 10 20
3: 20 20 20 10
Output of the example above (on node 0):
[ 7.367022] node (0, 0) -> 10
[ 7.367151] node (0, 1) -> 20
[ 7.367186] node (0, 2) -> 20
[ 7.367247] node (0, 3) -> 20
On a system with non-equidistant nodes (simulated using virtme-ng):
$ numactl -H
...
node distances:
node 0 1 2 3
0: 10 51 31 41
1: 51 10 21 61
2: 31 21 10 11
3: 41 61 11 10
Output of the example above (on node 0):
[ 8.953644] node (0, 0) -> 10
[ 8.953712] node (0, 2) -> 31
[ 8.953764] node (0, 3) -> 41
[ 8.953817] node (0, 1) -> 51
Suggested-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Acked-by: Yury Norov [NVIDIA] <yury.norov@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.