From 8302bd9afd4bc802c5ab2359bb5cb8d4bc55d04a Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Mon, 9 Nov 2020 21:06:56 +0000 Subject: x86/CPU/AMD: Save AMD NodeId as cpu_die_id [ Upstream commit 028c221ed1904af9ac3c5162ee98f48966de6b3d ] AMD systems provide a "NodeId" value that represents a global ID indicating to which "Node" a logical CPU belongs. The "Node" is a physical structure equivalent to a Die, and it should not be confused with logical structures like NUMA nodes. Logical nodes can be adjusted based on firmware or other settings whereas the physical nodes/dies are fixed based on hardware topology. The NodeId value can be used when a physical ID is needed by software. Save the AMD NodeId to struct cpuinfo_x86.cpu_die_id. Use the value from CPUID or MSR as appropriate. Default to phys_proc_id otherwise. Do so for both AMD and Hygon systems. Drop the node_id parameter from cacheinfo_*_init_llc_id() as it is no longer needed. Update the x86 topology documentation. Suggested-by: Borislav Petkov Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20201109210659.754018-2-Yazen.Ghannam@amd.com Signed-off-by: Sasha Levin --- Documentation/x86/topology.rst | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'Documentation/x86') diff --git a/Documentation/x86/topology.rst b/Documentation/x86/topology.rst index e29739904e37..7f58010ea86a 100644 --- a/Documentation/x86/topology.rst +++ b/Documentation/x86/topology.rst @@ -41,6 +41,8 @@ Package Packages contain a number of cores plus shared resources, e.g. DRAM controller, shared caches etc. +Modern systems may also use the term 'Die' for package. + AMD nomenclature for package is 'Node'. Package-related topology information in the kernel: @@ -53,11 +55,18 @@ Package-related topology information in the kernel: The number of dies in a package. This information is retrieved via CPUID. + - cpuinfo_x86.cpu_die_id: + + The physical ID of the die. This information is retrieved via CPUID. + - cpuinfo_x86.phys_proc_id: The physical ID of the package. This information is retrieved via CPUID and deduced from the APIC IDs of the cores in the package. + Modern systems use this value for the socket. There may be multiple + packages within a socket. This value may differ from cpu_die_id. + - cpuinfo_x86.logical_proc_id: The logical ID of the package. As we do not trust BIOSes to enumerate the -- cgit v1.2.3