2019-05-06 21:30:05

by Len Brown

[permalink] [raw]
Subject: [PATCH 02/22] topology: Simplify cputopology.txt formatting and wording

From: Len Brown <[email protected]>

Syntax only, no functional or semantic change.

Signed-off-by: Len Brown <[email protected]>
Cc: [email protected]
---
Documentation/cputopology.txt | 46 +++++++++++++++++------------------
1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt
index c6e7e9196a8b..cb61277e2308 100644
--- a/Documentation/cputopology.txt
+++ b/Documentation/cputopology.txt
@@ -3,79 +3,79 @@ How CPU topology info is exported via sysfs
===========================================

Export CPU topology info via sysfs. Items (attributes) are similar
-to /proc/cpuinfo output of some architectures:
+to /proc/cpuinfo output of some architectures. They reside in
+/sys/devices/system/cpu/cpuX/topology/:

-1) /sys/devices/system/cpu/cpuX/topology/physical_package_id:
+physical_package_id:

physical package id of cpuX. Typically corresponds to a physical
socket number, but the actual value is architecture and platform
dependent.

-2) /sys/devices/system/cpu/cpuX/topology/core_id:
+core_id:

the CPU core ID of cpuX. Typically it is the hardware platform's
identifier (rather than the kernel's). The actual value is
architecture and platform dependent.

-3) /sys/devices/system/cpu/cpuX/topology/book_id:
+book_id:

the book ID of cpuX. Typically it is the hardware platform's
identifier (rather than the kernel's). The actual value is
architecture and platform dependent.

-4) /sys/devices/system/cpu/cpuX/topology/drawer_id:
+drawer_id:

the drawer ID of cpuX. Typically it is the hardware platform's
identifier (rather than the kernel's). The actual value is
architecture and platform dependent.

-5) /sys/devices/system/cpu/cpuX/topology/thread_siblings:
+thread_siblings:

internal kernel map of cpuX's hardware threads within the same
core as cpuX.

-6) /sys/devices/system/cpu/cpuX/topology/thread_siblings_list:
+thread_siblings_list:

human-readable list of cpuX's hardware threads within the same
core as cpuX.

-7) /sys/devices/system/cpu/cpuX/topology/core_siblings:
+core_siblings:

internal kernel map of cpuX's hardware threads within the same
physical_package_id.

-8) /sys/devices/system/cpu/cpuX/topology/core_siblings_list:
+core_siblings_list:

human-readable list of cpuX's hardware threads within the same
physical_package_id.

-9) /sys/devices/system/cpu/cpuX/topology/book_siblings:
+book_siblings:

internal kernel map of cpuX's hardware threads within the same
book_id.

-10) /sys/devices/system/cpu/cpuX/topology/book_siblings_list:
+book_siblings_list:

human-readable list of cpuX's hardware threads within the same
book_id.

-11) /sys/devices/system/cpu/cpuX/topology/drawer_siblings:
+drawer_siblings:

internal kernel map of cpuX's hardware threads within the same
drawer_id.

-12) /sys/devices/system/cpu/cpuX/topology/drawer_siblings_list:
+drawer_siblings_list:

human-readable list of cpuX's hardware threads within the same
drawer_id.

-To implement it in an architecture-neutral way, a new source file,
-drivers/base/topology.c, is to export the 6 to 12 attributes. The book
-and drawer related sysfs files will only be created if CONFIG_SCHED_BOOK
-and CONFIG_SCHED_DRAWER are selected.
+Architecture-neutral, drivers/base/topology.c, exports these attributes.
+However, the book and drawer related sysfs files will only be created if
+CONFIG_SCHED_BOOK and CONFIG_SCHED_DRAWER are selected, respectively.

-CONFIG_SCHED_BOOK and CONFIG_DRAWER are currently only used on s390, where
-they reflect the cpu and cache hierarchy.
+CONFIG_SCHED_BOOK and CONFIG_SCHED_DRAWER are currently only used on s390,
+where they reflect the cpu and cache hierarchy.

For an architecture to support this feature, it must define some of
these macros in include/asm-XXX/topology.h::
@@ -98,10 +98,10 @@ To be consistent on all architectures, include/linux/topology.h
provides default definitions for any of the above macros that are
not defined by include/asm-XXX/topology.h:

-1) physical_package_id: -1
-2) core_id: 0
-3) sibling_cpumask: just the given CPU
-4) core_cpumask: just the given CPU
+1) topology_physical_package_id: -1
+2) topology_core_id: 0
+3) topology_sibling_cpumask: just the given CPU
+4) topology_core_cpumask: just the given CPU

For architectures that don't support books (CONFIG_SCHED_BOOK) there are no
default definitions for topology_book_id() and topology_book_cpumask().
--
2.18.0-rc0