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SubjectRe: [PATCH 03/27] Documentation: x86: convert topology.txt to reST
Em Fri, 26 Apr 2019 23:31:26 +0800
Changbin Du <changbin.du@gmail.com> escreveu:

> This converts the plain text documentation to reStructuredText format and
> add it to Sphinx TOC tree. No essential content change.
>
> Signed-off-by: Changbin Du <changbin.du@gmail.com>

Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

> ---
> Documentation/x86/index.rst | 1 +
> .../x86/{topology.txt => topology.rst} | 92 ++++++++++---------
> 2 files changed, 49 insertions(+), 44 deletions(-)
> rename Documentation/x86/{topology.txt => topology.rst} (74%)
>
> diff --git a/Documentation/x86/index.rst b/Documentation/x86/index.rst
> index 8f08caf4fbbb..2033791e53bc 100644
> --- a/Documentation/x86/index.rst
> +++ b/Documentation/x86/index.rst
> @@ -9,3 +9,4 @@ Linux x86 Support
> :numbered:
>
> boot
> + topology
> diff --git a/Documentation/x86/topology.txt b/Documentation/x86/topology.rst
> similarity index 74%
> rename from Documentation/x86/topology.txt
> rename to Documentation/x86/topology.rst
> index 2953e3ec9a02..5176e5315faa 100644
> --- a/Documentation/x86/topology.txt
> +++ b/Documentation/x86/topology.rst
> @@ -1,3 +1,6 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +============
> x86 Topology
> ============
>
> @@ -33,14 +36,14 @@ The topology of a system is described in the units of:
> - cores
> - threads
>
> -* Package:
> -
> - Packages contain a number of cores plus shared resources, e.g. DRAM
> - controller, shared caches etc.
> +Package
> +=======
> +Packages contain a number of cores plus shared resources, e.g. DRAM
> +controller, shared caches etc.
>
> - AMD nomenclature for package is 'Node'.
> +AMD nomenclature for package is 'Node'.
>
> - Package-related topology information in the kernel:
> +Package-related topology information in the kernel:
>
> - cpuinfo_x86.x86_max_cores:
>
> @@ -66,40 +69,41 @@ The topology of a system is described in the units of:
> - cpu_llc_id:
>
> A per-CPU variable containing:
> - - On Intel, the first APIC ID of the list of CPUs sharing the Last Level
> - Cache
>
> - - On AMD, the Node ID or Core Complex ID containing the Last Level
> - Cache. In general, it is a number identifying an LLC uniquely on the
> - system.
> + - On Intel, the first APIC ID of the list of CPUs sharing the Last Level
> + Cache
>
> -* Cores:
> + - On AMD, the Node ID or Core Complex ID containing the Last Level
> + Cache. In general, it is a number identifying an LLC uniquely on the
> + system.
>
> - A core consists of 1 or more threads. It does not matter whether the threads
> - are SMT- or CMT-type threads.
> +Cores
> +=====
> +A core consists of 1 or more threads. It does not matter whether the threads
> +are SMT- or CMT-type threads.
>
> - AMDs nomenclature for a CMT core is "Compute Unit". The kernel always uses
> - "core".
> +AMDs nomenclature for a CMT core is "Compute Unit". The kernel always uses
> +"core".
>
> - Core-related topology information in the kernel:
> +Core-related topology information in the kernel:
>
> - smp_num_siblings:
>
> The number of threads in a core. The number of threads in a package can be
> - calculated by:
> + calculated by::
>
> threads_per_package = cpuinfo_x86.x86_max_cores * smp_num_siblings
>
>
> -* Threads:
> +Threads
> +=======
> +A thread is a single scheduling unit. It's the equivalent to a logical Linux
> +CPU.
>
> - A thread is a single scheduling unit. It's the equivalent to a logical Linux
> - CPU.
> +AMDs nomenclature for CMT threads is "Compute Unit Core". The kernel always
> +uses "thread".
>
> - AMDs nomenclature for CMT threads is "Compute Unit Core". The kernel always
> - uses "thread".
> -
> - Thread-related topology information in the kernel:
> +Thread-related topology information in the kernel:
>
> - topology_core_cpumask():
>
> @@ -113,15 +117,15 @@ The topology of a system is described in the units of:
> The cpumask contains all online threads in the core to which a thread
> belongs.
>
> - - topology_logical_package_id():
> + - topology_logical_package_id():
>
> The logical package ID to which a thread belongs.
>
> - - topology_physical_package_id():
> + - topology_physical_package_id():
>
> The physical package ID to which a thread belongs.
>
> - - topology_core_id();
> + - topology_core_id();
>
> The ID of the core to which a thread belongs. It is also printed in /proc/cpuinfo
> "core_id."
> @@ -129,41 +133,41 @@ The topology of a system is described in the units of:
>
>
> System topology examples
> +========================
>
> -Note:
> -
> -The alternative Linux CPU enumeration depends on how the BIOS enumerates the
> -threads. Many BIOSes enumerate all threads 0 first and then all threads 1.
> -That has the "advantage" that the logical Linux CPU numbers of threads 0 stay
> -the same whether threads are enabled or not. That's merely an implementation
> -detail and has no practical impact.
> +.. note::
> + The alternative Linux CPU enumeration depends on how the BIOS enumerates the
> + threads. Many BIOSes enumerate all threads 0 first and then all threads 1.
> + That has the "advantage" that the logical Linux CPU numbers of threads 0 stay
> + the same whether threads are enabled or not. That's merely an implementation
> + detail and has no practical impact.
>
> -1) Single Package, Single Core
> +1) Single Package, Single Core::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
>
> 2) Single Package, Dual Core
>
> - a) One thread per core
> + a) One thread per core::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
> -> [core 1] -> [thread 0] -> Linux CPU 1
>
> - b) Two threads per core
> + b) Two threads per core::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
> -> [thread 1] -> Linux CPU 1
> -> [core 1] -> [thread 0] -> Linux CPU 2
> -> [thread 1] -> Linux CPU 3
>
> - Alternative enumeration:
> + Alternative enumeration::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
> -> [thread 1] -> Linux CPU 2
> -> [core 1] -> [thread 0] -> Linux CPU 1
> -> [thread 1] -> Linux CPU 3
>
> - AMD nomenclature for CMT systems:
> + AMD nomenclature for CMT systems::
>
> [node 0] -> [Compute Unit 0] -> [Compute Unit Core 0] -> Linux CPU 0
> -> [Compute Unit Core 1] -> Linux CPU 1
> @@ -172,7 +176,7 @@ detail and has no practical impact.
>
> 4) Dual Package, Dual Core
>
> - a) One thread per core
> + a) One thread per core::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
> -> [core 1] -> [thread 0] -> Linux CPU 1
> @@ -180,7 +184,7 @@ detail and has no practical impact.
> [package 1] -> [core 0] -> [thread 0] -> Linux CPU 2
> -> [core 1] -> [thread 0] -> Linux CPU 3
>
> - b) Two threads per core
> + b) Two threads per core::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
> -> [thread 1] -> Linux CPU 1
> @@ -192,7 +196,7 @@ detail and has no practical impact.
> -> [core 1] -> [thread 0] -> Linux CPU 6
> -> [thread 1] -> Linux CPU 7
>
> - Alternative enumeration:
> + Alternative enumeration::
>
> [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
> -> [thread 1] -> Linux CPU 4
> @@ -204,7 +208,7 @@ detail and has no practical impact.
> -> [core 1] -> [thread 0] -> Linux CPU 3
> -> [thread 1] -> Linux CPU 7
>
> - AMD nomenclature for CMT systems:
> + AMD nomenclature for CMT systems::
>
> [node 0] -> [Compute Unit 0] -> [Compute Unit Core 0] -> Linux CPU 0
> -> [Compute Unit Core 1] -> Linux CPU 1



Thanks,
Mauro

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