[PATCH 14/22] topology: Create package_cpus sysfs attribute

From: Len Brown <lenb@kernel.org>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, Len Brown <len.brown@intel.com>
Subject: [PATCH 14/22] topology: Create package_cpus sysfs attribute
Date: Mon,  6 May 2019 17:26:09 -0400	[thread overview]
Message-ID: <f73bf7714fd1e19c32bc5bec0237f7b15c388684.1557177585.git.len.brown@intel.com> (raw)
In-Reply-To: <6f53f0e494d743c79e18f6e3a98085711e6ddd0c.1557177585.git.len.brown@intel.com>

From: Len Brown <len.brown@intel.com>

The existing sysfs cpu/topology/core_siblings (and core_siblings_list)
attributes are documented, implemented, and used by programs to
represent set of logical CPUs sharing the same package.

This makes sense if the next topology level above a core
is always a package.  But on systems where there is a die
topology level between a core and a package, the name
and its definition become inconsistent.

So without changing its function, add a name for this map
that describes what it actually is -- package CPUs --
the set of CPUs that share the same package.

This new name will be immune to changes in topology, since
it describes threads at the current level, not siblings
at a contained level.

Signed-off-by: Len Brown <len.brown@intel.com>
Suggested-by: Brice Goglin <Brice.Goglin@inria.fr>
---
 Documentation/cputopology.txt | 12 ++++++------
 drivers/base/topology.c       |  6 ++++++
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt
index 2ff8a1e9a2db..48af5c290e20 100644
--- a/Documentation/cputopology.txt
+++ b/Documentation/cputopology.txt
@@ -46,15 +46,15 @@ thread_siblings_list:
 	human-readable list of cpuX's hardware threads within the same
 	core as cpuX.
 
-core_siblings:
+package_cpus:
 
-	internal kernel map of cpuX's hardware threads within the same
-	physical_package_id.
+	internal kernel map of the CPUs sharing the same physical_package_id.
+	(deprecated name: "core_siblings")
 
-core_siblings_list:
+package_cpus_list:
 
-	human-readable list of cpuX's hardware threads within the same
-	physical_package_id.
+	human-readable list of CPUs sharing the same physical_package_id.
+	(deprecated name: "core_siblings_list")
 
 book_siblings:
 
diff --git a/drivers/base/topology.c b/drivers/base/topology.c
index 50352cf96f85..dc3c19b482f3 100644
--- a/drivers/base/topology.c
+++ b/drivers/base/topology.c
@@ -57,6 +57,10 @@ define_siblings_show_func(core_siblings, core_cpumask);
 static DEVICE_ATTR_RO(core_siblings);
 static DEVICE_ATTR_RO(core_siblings_list);
 
+define_siblings_show_func(package_cpus, core_cpumask);
+static DEVICE_ATTR_RO(package_cpus);
+static DEVICE_ATTR_RO(package_cpus_list);
+
 #ifdef CONFIG_SCHED_BOOK
 define_id_show_func(book_id);
 static DEVICE_ATTR_RO(book_id);
@@ -81,6 +85,8 @@ static struct attribute *default_attrs[] = {
 	&dev_attr_thread_siblings_list.attr,
 	&dev_attr_core_siblings.attr,
 	&dev_attr_core_siblings_list.attr,
+	&dev_attr_package_cpus.attr,
+	&dev_attr_package_cpus_list.attr,
 #ifdef CONFIG_SCHED_BOOK
 	&dev_attr_book_id.attr,
 	&dev_attr_book_siblings.attr,
-- 
2.18.0-rc0

