425752c63b
On IBM POWER9, the device tree exposes a property array identifed by "ibm,thread-groups" which will indicate which groups of threads share a particular set of resources. As of today we only have one form of grouping identifying the group of threads in the core that share the L1 cache, translation cache and instruction data flow. This patch adds helper functions to parse the contents of "ibm,thread-groups" and populate a per-cpu variable to cache information about siblings of each CPU that share the L1, traslation cache and instruction data-flow. It also defines a new global variable named "has_big_cores" which indicates if the cores on this configuration have multiple groups of threads that share L1 cache. For each online CPU, it maintains a cpu_smallcore_mask, which indicates the online siblings which share the L1-cache with it. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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 Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
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.