[tip: x86/cpu] x86/CPU/AMD: Save AMD NodeId as cpu_die_id

From: tip-bot2 for Yazen Ghannam
Date: Thu Nov 19 2020 - 06:29:43 EST


The following commit has been merged into the x86/cpu branch of tip:

Commit-ID: 028c221ed1904af9ac3c5162ee98f48966de6b3d
Gitweb: https://git.kernel.org/tip/028c221ed1904af9ac3c5162ee98f48966de6b3d
Author: Yazen Ghannam <yazen.ghannam@xxxxxxx>
AuthorDate: Mon, 09 Nov 2020 21:06:56
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Thu, 19 Nov 2020 11:43:13 +01:00

x86/CPU/AMD: Save AMD NodeId as cpu_die_id

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 <bp@xxxxxxxxx>
Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20201109210659.754018-2-Yazen.Ghannam@xxxxxxx
---
Documentation/x86/topology.rst | 9 +++++++++
arch/x86/include/asm/cacheinfo.h | 4 ++--
arch/x86/kernel/cpu/amd.c | 11 +++++------
arch/x86/kernel/cpu/cacheinfo.c | 6 +++---
arch/x86/kernel/cpu/hygon.c | 11 +++++------
5 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/Documentation/x86/topology.rst b/Documentation/x86/topology.rst
index e297399..7f58010 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
diff --git a/arch/x86/include/asm/cacheinfo.h b/arch/x86/include/asm/cacheinfo.h
index 86b63c7..86b2e0d 100644
--- a/arch/x86/include/asm/cacheinfo.h
+++ b/arch/x86/include/asm/cacheinfo.h
@@ -2,7 +2,7 @@
#ifndef _ASM_X86_CACHEINFO_H
#define _ASM_X86_CACHEINFO_H

-void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id);
-void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id);
+void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu);
+void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu);

#endif /* _ASM_X86_CACHEINFO_H */
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 6062ce5..2f1fbd8 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -330,7 +330,6 @@ static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
*/
static void amd_get_topology(struct cpuinfo_x86 *c)
{
- u8 node_id;
int cpu = smp_processor_id();

/* get information required for multi-node processors */
@@ -340,7 +339,7 @@ static void amd_get_topology(struct cpuinfo_x86 *c)

cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);

- node_id = ecx & 0xff;
+ c->cpu_die_id = ecx & 0xff;

if (c->x86 == 0x15)
c->cu_id = ebx & 0xff;
@@ -360,15 +359,15 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
if (!err)
c->x86_coreid_bits = get_count_order(c->x86_max_cores);

- cacheinfo_amd_init_llc_id(c, cpu, node_id);
+ cacheinfo_amd_init_llc_id(c, cpu);

} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
u64 value;

rdmsrl(MSR_FAM10H_NODE_ID, value);
- node_id = value & 7;
+ c->cpu_die_id = value & 7;

- per_cpu(cpu_llc_id, cpu) = node_id;
+ per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
} else
return;

@@ -393,7 +392,7 @@ static void amd_detect_cmp(struct cpuinfo_x86 *c)
/* Convert the initial APIC ID into the socket ID */
c->phys_proc_id = c->initial_apicid >> bits;
/* use socket ID also for last level cache */
- per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
+ per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
}

static void amd_detect_ppin(struct cpuinfo_x86 *c)
diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c
index 57074cf..f9ac682 100644
--- a/arch/x86/kernel/cpu/cacheinfo.c
+++ b/arch/x86/kernel/cpu/cacheinfo.c
@@ -646,7 +646,7 @@ static int find_num_cache_leaves(struct cpuinfo_x86 *c)
return i;
}

-void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id)
+void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu)
{
/*
* We may have multiple LLCs if L3 caches exist, so check if we
@@ -657,7 +657,7 @@ void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id)

if (c->x86 < 0x17) {
/* LLC is at the node level. */
- per_cpu(cpu_llc_id, cpu) = node_id;
+ per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
} else if (c->x86 == 0x17 && c->x86_model <= 0x1F) {
/*
* LLC is at the core complex level.
@@ -684,7 +684,7 @@ void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id)
}
}

-void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id)
+void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu)
{
/*
* We may have multiple LLCs if L3 caches exist, so check if we
diff --git a/arch/x86/kernel/cpu/hygon.c b/arch/x86/kernel/cpu/hygon.c
index ac6c30e..dc0840a 100644
--- a/arch/x86/kernel/cpu/hygon.c
+++ b/arch/x86/kernel/cpu/hygon.c
@@ -65,7 +65,6 @@ static void hygon_get_topology_early(struct cpuinfo_x86 *c)
*/
static void hygon_get_topology(struct cpuinfo_x86 *c)
{
- u8 node_id;
int cpu = smp_processor_id();

/* get information required for multi-node processors */
@@ -75,7 +74,7 @@ static void hygon_get_topology(struct cpuinfo_x86 *c)

cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);

- node_id = ecx & 0xff;
+ c->cpu_die_id = ecx & 0xff;

c->cpu_core_id = ebx & 0xff;

@@ -93,14 +92,14 @@ static void hygon_get_topology(struct cpuinfo_x86 *c)
/* Socket ID is ApicId[6] for these processors. */
c->phys_proc_id = c->apicid >> APICID_SOCKET_ID_BIT;

- cacheinfo_hygon_init_llc_id(c, cpu, node_id);
+ cacheinfo_hygon_init_llc_id(c, cpu);
} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
u64 value;

rdmsrl(MSR_FAM10H_NODE_ID, value);
- node_id = value & 7;
+ c->cpu_die_id = value & 7;

- per_cpu(cpu_llc_id, cpu) = node_id;
+ per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
} else
return;

@@ -123,7 +122,7 @@ static void hygon_detect_cmp(struct cpuinfo_x86 *c)
/* Convert the initial APIC ID into the socket ID */
c->phys_proc_id = c->initial_apicid >> bits;
/* use socket ID also for last level cache */
- per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
+ per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
}

static void srat_detect_node(struct cpuinfo_x86 *c)