[tip: x86/core] x86/cpu: Encapsulate topology information in cpuinfo_x86

From: tip-bot2 for Thomas Gleixner
Date: Fri Oct 13 2023 - 05:39:25 EST


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

Commit-ID: b9655e702dc5d856e5e05ae414b71708ca98b30c
Gitweb: https://git.kernel.org/tip/b9655e702dc5d856e5e05ae414b71708ca98b30c
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Mon, 14 Aug 2023 10:18:29 +02:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Tue, 10 Oct 2023 14:38:17 +02:00

x86/cpu: Encapsulate topology information in cpuinfo_x86

The topology related information is randomly scattered across cpuinfo_x86.

Create a new structure cpuinfo_topo and move in a first step initial_apicid
and apicid into it.

Aside of being better readable this is in preparation for replacing the
horribly fragile CPU topology evaluation code further down the road.

Consolidate APIC ID fields to u32 as that represents the hardware type.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Tested-by: Juergen Gross <jgross@xxxxxxxx>
Tested-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Tested-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Tested-by: Zhang Rui <rui.zhang@xxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230814085112.269787744@xxxxxxxxxxxxx

---
arch/x86/include/asm/processor.h | 14 +++++++++-----
arch/x86/kernel/cpu/amd.c | 10 +++++-----
arch/x86/kernel/cpu/cacheinfo.c | 20 ++++++++++----------
arch/x86/kernel/cpu/common.c | 18 +++++++++---------
arch/x86/kernel/cpu/hygon.c | 12 ++++++------
arch/x86/kernel/cpu/mce/apei.c | 2 +-
arch/x86/kernel/cpu/mce/core.c | 2 +-
arch/x86/kernel/cpu/proc.c | 4 ++--
arch/x86/kernel/cpu/topology.c | 12 ++++++------
arch/x86/xen/apic.c | 2 +-
drivers/gpu/drm/amd/amdkfd/kfd_topology.c | 2 +-
drivers/virt/acrn/hsm.c | 2 +-
12 files changed, 52 insertions(+), 48 deletions(-)

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 0086920..6833962 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -75,11 +75,16 @@ extern u16 __read_mostly tlb_lld_4m[NR_INFO];
extern u16 __read_mostly tlb_lld_1g[NR_INFO];

/*
- * CPU type and hardware bug flags. Kept separately for each CPU.
- * Members of this structure are referenced in head_32.S, so think twice
- * before touching them. [mj]
+ * CPU type and hardware bug flags. Kept separately for each CPU.
*/

+struct cpuinfo_topology {
+ // Real APIC ID read from the local APIC
+ u32 apicid;
+ // The initial APIC ID provided by CPUID
+ u32 initial_apicid;
+};
+
struct cpuinfo_x86 {
__u8 x86; /* CPU family */
__u8 x86_vendor; /* CPU vendor */
@@ -112,6 +117,7 @@ struct cpuinfo_x86 {
};
char x86_vendor_id[16];
char x86_model_id[64];
+ struct cpuinfo_topology topo;
/* in KB - valid for CPUS which support this call: */
unsigned int x86_cache_size;
int x86_cache_alignment; /* In bytes */
@@ -125,8 +131,6 @@ struct cpuinfo_x86 {
u64 ppin;
/* cpuid returned max cores value: */
u16 x86_max_cores;
- u16 apicid;
- u16 initial_apicid;
u16 x86_clflush_size;
/* number of cores as seen by the OS: */
u16 booted_cores;
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index dd8379d..1406659 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -459,9 +459,9 @@ static void amd_detect_cmp(struct cpuinfo_x86 *c)

bits = c->x86_coreid_bits;
/* Low order bits define the core id (index of core in socket) */
- c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
+ c->cpu_core_id = c->topo.initial_apicid & ((1 << bits)-1);
/* Convert the initial APIC ID into the socket ID */
- c->phys_proc_id = c->initial_apicid >> bits;
+ c->phys_proc_id = c->topo.initial_apicid >> bits;
/* use socket ID also for last level cache */
per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
}
@@ -477,7 +477,7 @@ static void srat_detect_node(struct cpuinfo_x86 *c)
#ifdef CONFIG_NUMA
int cpu = smp_processor_id();
int node;
- unsigned apicid = c->apicid;
+ unsigned apicid = c->topo.apicid;

node = numa_cpu_node(cpu);
if (node == NUMA_NO_NODE)
@@ -511,7 +511,7 @@ static void srat_detect_node(struct cpuinfo_x86 *c)
* through CPU mapping may alter the outcome, directly
* access __apicid_to_node[].
*/
- int ht_nodeid = c->initial_apicid;
+ int ht_nodeid = c->topo.initial_apicid;

if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
node = __apicid_to_node[ht_nodeid];
@@ -1047,7 +1047,7 @@ static void init_amd(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_FSRS);

/* get apicid instead of initial apic id from cpuid */
- c->apicid = read_apic_id();
+ c->topo.apicid = read_apic_id();

/* K6s reports MCEs but don't actually have all the MSRs */
if (c->x86 < 6)
diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c
index 8f86eac..daa3542 100644
--- a/arch/x86/kernel/cpu/cacheinfo.c
+++ b/arch/x86/kernel/cpu/cacheinfo.c
@@ -678,7 +678,7 @@ void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu)
* LLC is at the core complex level.
* Core complex ID is ApicId[3] for these processors.
*/
- per_cpu(cpu_llc_id, cpu) = c->apicid >> 3;
+ per_cpu(cpu_llc_id, cpu) = c->topo.apicid >> 3;
} else {
/*
* LLC ID is calculated from the number of threads sharing the
@@ -694,7 +694,7 @@ void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu)
if (num_sharing_cache) {
int bits = get_count_order(num_sharing_cache);

- per_cpu(cpu_llc_id, cpu) = c->apicid >> bits;
+ per_cpu(cpu_llc_id, cpu) = c->topo.apicid >> bits;
}
}
}
@@ -712,7 +712,7 @@ void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu)
* LLC is at the core complex level.
* Core complex ID is ApicId[3] for these processors.
*/
- per_cpu(cpu_llc_id, cpu) = c->apicid >> 3;
+ per_cpu(cpu_llc_id, cpu) = c->topo.apicid >> 3;
}

void init_amd_cacheinfo(struct cpuinfo_x86 *c)
@@ -776,13 +776,13 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
new_l2 = this_leaf.size/1024;
num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
index_msb = get_count_order(num_threads_sharing);
- l2_id = c->apicid & ~((1 << index_msb) - 1);
+ l2_id = c->topo.apicid & ~((1 << index_msb) - 1);
break;
case 3:
new_l3 = this_leaf.size/1024;
num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
index_msb = get_count_order(num_threads_sharing);
- l3_id = c->apicid & ~((1 << index_msb) - 1);
+ l3_id = c->topo.apicid & ~((1 << index_msb) - 1);
break;
default:
break;
@@ -915,7 +915,7 @@ static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
unsigned int apicid, nshared, first, last;

nshared = base->eax.split.num_threads_sharing + 1;
- apicid = cpu_data(cpu).apicid;
+ apicid = cpu_data(cpu).topo.apicid;
first = apicid - (apicid % nshared);
last = first + nshared - 1;

@@ -924,14 +924,14 @@ static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
if (!this_cpu_ci->info_list)
continue;

- apicid = cpu_data(i).apicid;
+ apicid = cpu_data(i).topo.apicid;
if ((apicid < first) || (apicid > last))
continue;

this_leaf = this_cpu_ci->info_list + index;

for_each_online_cpu(sibling) {
- apicid = cpu_data(sibling).apicid;
+ apicid = cpu_data(sibling).topo.apicid;
if ((apicid < first) || (apicid > last))
continue;
cpumask_set_cpu(sibling,
@@ -969,7 +969,7 @@ static void __cache_cpumap_setup(unsigned int cpu, int index,
index_msb = get_count_order(num_threads_sharing);

for_each_online_cpu(i)
- if (cpu_data(i).apicid >> index_msb == c->apicid >> index_msb) {
+ if (cpu_data(i).topo.apicid >> index_msb == c->topo.apicid >> index_msb) {
struct cpu_cacheinfo *sib_cpu_ci = get_cpu_cacheinfo(i);

if (i == cpu || !sib_cpu_ci->info_list)
@@ -1024,7 +1024,7 @@ static void get_cache_id(int cpu, struct _cpuid4_info_regs *id4_regs)

num_threads_sharing = 1 + id4_regs->eax.split.num_threads_sharing;
index_msb = get_count_order(num_threads_sharing);
- id4_regs->id = c->apicid >> index_msb;
+ id4_regs->id = c->topo.apicid >> index_msb;
}

int populate_cache_leaves(unsigned int cpu)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 382d4e6..c39e88e 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -914,7 +914,7 @@ void detect_ht(struct cpuinfo_x86 *c)
return;

index_msb = get_count_order(smp_num_siblings);
- c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
+ c->phys_proc_id = apic->phys_pkg_id(c->topo.initial_apicid, index_msb);

smp_num_siblings = smp_num_siblings / c->x86_max_cores;

@@ -922,7 +922,7 @@ void detect_ht(struct cpuinfo_x86 *c)

core_bits = get_count_order(c->x86_max_cores);

- c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
+ c->cpu_core_id = apic->phys_pkg_id(c->topo.initial_apicid, index_msb) &
((1 << core_bits) - 1);
#endif
}
@@ -1761,15 +1761,15 @@ static void generic_identify(struct cpuinfo_x86 *c)
get_cpu_address_sizes(c);

if (c->cpuid_level >= 0x00000001) {
- c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
+ c->topo.initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
#ifdef CONFIG_X86_32
# ifdef CONFIG_SMP
- c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
+ c->topo.apicid = apic->phys_pkg_id(c->topo.initial_apicid, 0);
# else
- c->apicid = c->initial_apicid;
+ c->topo.apicid = c->topo.initial_apicid;
# endif
#endif
- c->phys_proc_id = c->initial_apicid;
+ c->phys_proc_id = c->topo.initial_apicid;
}

get_model_name(c); /* Default name */
@@ -1803,9 +1803,9 @@ static void validate_apic_and_package_id(struct cpuinfo_x86 *c)

apicid = apic->cpu_present_to_apicid(cpu);

- if (apicid != c->apicid) {
+ if (apicid != c->topo.apicid) {
pr_err(FW_BUG "CPU%u: APIC id mismatch. Firmware: %x APIC: %x\n",
- cpu, apicid, c->initial_apicid);
+ cpu, apicid, c->topo.initial_apicid);
}
BUG_ON(topology_update_package_map(c->phys_proc_id, cpu));
BUG_ON(topology_update_die_map(c->cpu_die_id, cpu));
@@ -1855,7 +1855,7 @@ static void identify_cpu(struct cpuinfo_x86 *c)
apply_forced_caps(c);

#ifdef CONFIG_X86_64
- c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
+ c->topo.apicid = apic->phys_pkg_id(c->topo.initial_apicid, 0);
#endif

/*
diff --git a/arch/x86/kernel/cpu/hygon.c b/arch/x86/kernel/cpu/hygon.c
index a7b3ef4..320d18d 100644
--- a/arch/x86/kernel/cpu/hygon.c
+++ b/arch/x86/kernel/cpu/hygon.c
@@ -92,7 +92,7 @@ static void hygon_get_topology(struct cpuinfo_x86 *c)
* when running on host.
*/
if (!boot_cpu_has(X86_FEATURE_HYPERVISOR) && c->x86_model <= 0x3)
- c->phys_proc_id = c->apicid >> APICID_SOCKET_ID_BIT;
+ c->phys_proc_id = c->topo.apicid >> APICID_SOCKET_ID_BIT;

cacheinfo_hygon_init_llc_id(c, cpu);
} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
@@ -120,9 +120,9 @@ static void hygon_detect_cmp(struct cpuinfo_x86 *c)

bits = c->x86_coreid_bits;
/* Low order bits define the core id (index of core in socket) */
- c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
+ c->cpu_core_id = c->topo.initial_apicid & ((1 << bits)-1);
/* Convert the initial APIC ID into the socket ID */
- c->phys_proc_id = c->initial_apicid >> bits;
+ c->phys_proc_id = c->topo.initial_apicid >> bits;
/* use socket ID also for last level cache */
per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
}
@@ -132,7 +132,7 @@ static void srat_detect_node(struct cpuinfo_x86 *c)
#ifdef CONFIG_NUMA
int cpu = smp_processor_id();
int node;
- unsigned int apicid = c->apicid;
+ unsigned int apicid = c->topo.apicid;

node = numa_cpu_node(cpu);
if (node == NUMA_NO_NODE)
@@ -165,7 +165,7 @@ static void srat_detect_node(struct cpuinfo_x86 *c)
* through CPU mapping may alter the outcome, directly
* access __apicid_to_node[].
*/
- int ht_nodeid = c->initial_apicid;
+ int ht_nodeid = c->topo.initial_apicid;

if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
node = __apicid_to_node[ht_nodeid];
@@ -305,7 +305,7 @@ static void init_hygon(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);

/* get apicid instead of initial apic id from cpuid */
- c->apicid = read_apic_id();
+ c->topo.apicid = read_apic_id();

/*
* XXX someone from Hygon needs to confirm this DTRT
diff --git a/arch/x86/kernel/cpu/mce/apei.c b/arch/x86/kernel/cpu/mce/apei.c
index 8ed3417..adb37b8 100644
--- a/arch/x86/kernel/cpu/mce/apei.c
+++ b/arch/x86/kernel/cpu/mce/apei.c
@@ -103,7 +103,7 @@ int apei_smca_report_x86_error(struct cper_ia_proc_ctx *ctx_info, u64 lapic_id)
m.socketid = -1;

for_each_possible_cpu(cpu) {
- if (cpu_data(cpu).initial_apicid == lapic_id) {
+ if (cpu_data(cpu).topo.initial_apicid == lapic_id) {
m.extcpu = cpu;
m.socketid = cpu_data(m.extcpu).phys_proc_id;
break;
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 6f35f72..b5e9288 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -124,7 +124,7 @@ void mce_setup(struct mce *m)
m->cpuvendor = boot_cpu_data.x86_vendor;
m->cpuid = cpuid_eax(1);
m->socketid = cpu_data(m->extcpu).phys_proc_id;
- m->apicid = cpu_data(m->extcpu).initial_apicid;
+ m->apicid = cpu_data(m->extcpu).topo.initial_apicid;
m->mcgcap = __rdmsr(MSR_IA32_MCG_CAP);
m->ppin = cpu_data(m->extcpu).ppin;
m->microcode = boot_cpu_data.microcode;
diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
index 31c0e68..91eb0bc 100644
--- a/arch/x86/kernel/cpu/proc.c
+++ b/arch/x86/kernel/cpu/proc.c
@@ -25,8 +25,8 @@ static void show_cpuinfo_core(struct seq_file *m, struct cpuinfo_x86 *c,
cpumask_weight(topology_core_cpumask(cpu)));
seq_printf(m, "core id\t\t: %d\n", c->cpu_core_id);
seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
- seq_printf(m, "apicid\t\t: %d\n", c->apicid);
- seq_printf(m, "initial apicid\t: %d\n", c->initial_apicid);
+ seq_printf(m, "apicid\t\t: %d\n", c->topo.apicid);
+ seq_printf(m, "initial apicid\t: %d\n", c->topo.initial_apicid);
#endif
}

diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c
index 0270925..73c47a8 100644
--- a/arch/x86/kernel/cpu/topology.c
+++ b/arch/x86/kernel/cpu/topology.c
@@ -78,7 +78,7 @@ int detect_extended_topology_early(struct cpuinfo_x86 *c)
/*
* initial apic id, which also represents 32-bit extended x2apic id.
*/
- c->initial_apicid = edx;
+ c->topo.initial_apicid = edx;
smp_num_siblings = max_t(int, smp_num_siblings, LEVEL_MAX_SIBLINGS(ebx));
#endif
return 0;
@@ -108,7 +108,7 @@ int detect_extended_topology(struct cpuinfo_x86 *c)
* Populate HT related information from sub-leaf level 0.
*/
cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);
- c->initial_apicid = edx;
+ c->topo.initial_apicid = edx;
core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);
smp_num_siblings = max_t(int, smp_num_siblings, LEVEL_MAX_SIBLINGS(ebx));
core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);
@@ -146,20 +146,20 @@ int detect_extended_topology(struct cpuinfo_x86 *c)
die_select_mask = (~(-1 << die_plus_mask_width)) >>
core_plus_mask_width;

- c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid,
+ c->cpu_core_id = apic->phys_pkg_id(c->topo.initial_apicid,
ht_mask_width) & core_select_mask;

if (die_level_present) {
- c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid,
+ c->cpu_die_id = apic->phys_pkg_id(c->topo.initial_apicid,
core_plus_mask_width) & die_select_mask;
}

- c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,
+ c->phys_proc_id = apic->phys_pkg_id(c->topo.initial_apicid,
pkg_mask_width);
/*
* Reinit the apicid, now that we have extended initial_apicid.
*/
- c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
+ c->topo.apicid = apic->phys_pkg_id(c->topo.initial_apicid, 0);

c->x86_max_cores = (core_level_siblings / smp_num_siblings);
__max_die_per_package = (die_level_siblings / core_level_siblings);
diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
index 7ad9122..958b747 100644
--- a/arch/x86/xen/apic.c
+++ b/arch/x86/xen/apic.c
@@ -118,7 +118,7 @@ static int xen_phys_pkg_id(int initial_apic_id, int index_msb)
static int xen_cpu_present_to_apicid(int cpu)
{
if (cpu_present(cpu))
- return cpu_data(cpu).apicid;
+ return cpu_data(cpu).topo.apicid;
else
return BAD_APICID;
}
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_topology.c b/drivers/gpu/drm/amd/amdkfd/kfd_topology.c
index ff98fde..70acfbb 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_topology.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_topology.c
@@ -2209,7 +2209,7 @@ static int kfd_cpumask_to_apic_id(const struct cpumask *cpumask)
if (first_cpu_of_numa_node >= nr_cpu_ids)
return -1;
#ifdef CONFIG_X86_64
- return cpu_data(first_cpu_of_numa_node).apicid;
+ return cpu_data(first_cpu_of_numa_node).topo.apicid;
#else
return first_cpu_of_numa_node;
#endif
diff --git a/drivers/virt/acrn/hsm.c b/drivers/virt/acrn/hsm.c
index 423ea88..c24036c 100644
--- a/drivers/virt/acrn/hsm.c
+++ b/drivers/virt/acrn/hsm.c
@@ -447,7 +447,7 @@ static ssize_t remove_cpu_store(struct device *dev,
if (cpu_online(cpu))
remove_cpu(cpu);

- lapicid = cpu_data(cpu).apicid;
+ lapicid = cpu_data(cpu).topo.apicid;
dev_dbg(dev, "Try to remove cpu %lld with lapicid %lld\n", cpu, lapicid);
ret = hcall_sos_remove_cpu(lapicid);
if (ret < 0) {