a4c421b12c
commit 2c88d45edbb89029c1190bb3b136d2602f057c98 upstream.
Commit 1340ccfa9a9a ("x86,sched: Allow topologies where NUMA nodes
share an LLC") added a vendor and model specific check to never
call topology_sane() for Intel Skylake Server systems where NUMA
nodes share an LLC.
Intel Ice Lake and Sapphire Rapids CPUs also enumerate an LLC that is
shared by multiple NUMA nodes. The LLC on these CPUs is shared for
off-package data access but private to the NUMA node for on-package
access. Rather than managing a list of allowable SNC topologies, make
this SNC topology the default, and treat Intel's Cluster-On-Die (COD)
topology as the exception.
In SNC mode, Sky Lake, Ice Lake, and Sapphire Rapids servers do not
emit this warning:
sched: CPU #3's llc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency.
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20210310190233.31752-1-alison.schofield@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.
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.