From: Len Brown <len.brown@xxxxxxxxx>
Some new systems have multiple software-visible die within each package.
Update Linux parsing of the Intel CPUID "Extended Topology Leaf"
to handle either CPUID.B, or the new CPUID.1F.
Add cpuinfo_x86.die_id and cpuinfo_x86.max_dies to store the result.
die_id will be non-zero only for multi-die/package systems.
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
Cc: linux-doc@xxxxxxxxxxxxxxx
---
Documentation/x86/topology.rst | 4 ++
arch/x86/include/asm/processor.h | 4 +-
arch/x86/kernel/cpu/topology.c | 85 +++++++++++++++++++++++++-------
arch/x86/kernel/smpboot.c | 2 +
4 files changed, 75 insertions(+), 20 deletions(-)
diff --git a/Documentation/x86/topology.rst b/Documentation/x86/topology.rst
index 6e28dbe818ab..8e9704f61017 100644
--- a/Documentation/x86/topology.rst
+++ b/Documentation/x86/topology.rst
@@ -49,6 +49,10 @@ Package-related topology information in the kernel:
The number of cores in a package. This information is retrieved via CPUID.
+ - cpuinfo_x86.x86_max_dies:
+
+ The number of dies in a package. This information is retrieved via CPUID.
+
- cpuinfo_x86.phys_proc_id:
The physical ID of the package. This information is retrieved via CPUID
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 7e99ef67bff0..00fc03a8da59 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -105,7 +105,8 @@ struct cpuinfo_x86 {
int x86_power;
unsigned long loops_per_jiffy;
/* cpuid returned max cores value: */
- u16 x86_max_cores;
+ u16 x86_max_cores;
+ u16 x86_max_dies;
u16 apicid;
u16 initial_apicid;
u16 x86_clflush_size;
@@ -117,6 +118,7 @@ struct cpuinfo_x86 {
u16 logical_proc_id;
/* Core id: */
u16 cpu_core_id;
+ u16 cpu_die_id;
/* Index into per_cpu list: */
u16 cpu_index;
u32 microcode;
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c
index 8f6c784141d1..4d17e699657d 100644
--- a/arch/x86/kernel/cpu/topology.c
+++ b/arch/x86/kernel/cpu/topology.c
@@ -15,33 +15,63 @@
/* leaf 0xb SMT level */
#define SMT_LEVEL 0
-/* leaf 0xb sub-leaf types */
+/* extended topology sub-leaf types */
#define INVALID_TYPE 0
#define SMT_TYPE 1
#define CORE_TYPE 2
+#define DIE_TYPE 5
#define LEAFB_SUBTYPE(ecx) (((ecx) >> 8) & 0xff)
#define BITS_SHIFT_NEXT_LEVEL(eax) ((eax) & 0x1f)
#define LEVEL_MAX_SIBLINGS(ebx) ((ebx) & 0xffff)
-int detect_extended_topology_early(struct cpuinfo_x86 *c)
-{
#ifdef CONFIG_SMP
+/*
+ * Check if given CPUID extended toplogy "leaf" is implemented
+ */
+static int check_extended_topology_leaf(int leaf)
+{
unsigned int eax, ebx, ecx, edx;
- if (c->cpuid_level < 0xb)
+ cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+
+ if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
return -1;
- cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+ return 0;
+}
+/*
+ * Return best CPUID Extended Toplogy Leaf supported
+ */
+static int detect_extended_topology_leaf(struct cpuinfo_x86 *c)
+{
+ if (c->cpuid_level >= 0x1f) {
+ if (check_extended_topology_leaf(0x1f) == 0)
+ return 0x1f;
+ }
- /*
- * check if the cpuid leaf 0xb is actually implemented.
- */
- if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))
+ if (c->cpuid_level >= 0xb) {
+ if (check_extended_topology_leaf(0xb) == 0)
+ return 0xb;
+ }
+
+ return -1;
+}
+#endif
+
+int detect_extended_topology_early(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+ unsigned int eax, ebx, ecx, edx;
+ int leaf;
+
+ leaf = detect_extended_topology_leaf(c);
+ if (leaf < 0)
return -1;
set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
+ cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
/*
* initial apic id, which also represents 32-bit extended x2apic id.
*/
@@ -52,7 +82,7 @@ int detect_extended_topology_early(struct cpuinfo_x86 *c)
}
/*
- * Check for extended topology enumeration cpuid leaf 0xb and if it
+ * Check for extended topology enumeration cpuid leaf, and if it
* exists, use it for populating initial_apicid and cpu topology
* detection.
*/
@@ -60,22 +90,28 @@ int detect_extended_topology(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_SMP
unsigned int eax, ebx, ecx, edx, sub_index;
- unsigned int ht_mask_width, core_plus_mask_width;
+ unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width;
unsigned int core_select_mask, core_level_siblings;
+ unsigned int die_select_mask, die_level_siblings;
+ int leaf;
- if (detect_extended_topology_early(c) < 0)
+ leaf = detect_extended_topology_leaf(c);
+ if (leaf < 0)
return -1;
/*
* Populate HT related information from sub-leaf level 0.
*/
- cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+ cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
+ c->initial_apicid = edx;
core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx);
core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+ die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+ die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
sub_index = 1;
do {
- cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx);
+ cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx);
/*
* Check for the Core type in the implemented sub leaves.
@@ -83,23 +119,34 @@ int detect_extended_topology(struct cpuinfo_x86 *c)
if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {
core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
- break;
+ die_level_siblings = core_level_siblings;
+ die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
+ }
+ if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) {
+ die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
+ die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
}
sub_index++;
} while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);
core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width;
-
- c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width)
- & core_select_mask;
- c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, core_plus_mask_width);
+ die_select_mask = (~(-1 << die_plus_mask_width)) >>
+ core_plus_mask_width;
+
+ c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid,
+ ht_mask_width) & core_select_mask;
+ c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid,
+ core_plus_mask_width) & die_select_mask;
+ c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,
+ die_plus_mask_width);
/*
* Reinit the apicid, now that we have extended initial_apicid.
*/
c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
c->x86_max_cores = (core_level_siblings / smp_num_siblings);
+ c->x86_max_dies = (die_level_siblings / core_level_siblings);
#endif
return 0;
}
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 73e69aaaa117..40ffe23249c0 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -389,6 +389,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
if (c->phys_proc_id == o->phys_proc_id &&
+ c->cpu_die_id == o->cpu_die_id &&
per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {
if (c->cpu_core_id == o->cpu_core_id)
return topology_sane(c, o, "smt");
@@ -400,6 +401,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
}
} else if (c->phys_proc_id == o->phys_proc_id &&
+ c->cpu_die_id == o->cpu_die_id &&
c->cpu_core_id == o->cpu_core_id) {
return topology_sane(c, o, "smt");
}
--
2.18.0-rc0
