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-rw-r--r--Documentation/x86/topology.txt208
-rw-r--r--arch/x86/events/amd/core.c21
-rw-r--r--arch/x86/events/perf_event.h5
-rw-r--r--arch/x86/include/asm/msr-index.h8
-rw-r--r--arch/x86/include/asm/processor.h2
-rw-r--r--arch/x86/include/asm/smp.h1
-rw-r--r--arch/x86/include/asm/thread_info.h6
-rw-r--r--arch/x86/kernel/amd_nb.c6
-rw-r--r--arch/x86/kernel/cpu/amd.c12
-rw-r--r--arch/x86/kernel/cpu/powerflags.c2
-rw-r--r--arch/x86/kernel/smpboot.c2
-rw-r--r--arch/x86/ras/mce_amd_inj.c3
12 files changed, 246 insertions, 30 deletions
diff --git a/Documentation/x86/topology.txt b/Documentation/x86/topology.txt
new file mode 100644
index 000000000000..06afac252f5b
--- /dev/null
+++ b/Documentation/x86/topology.txt
@@ -0,0 +1,208 @@
+x86 Topology
+============
+
+This documents and clarifies the main aspects of x86 topology modelling and
+representation in the kernel. Update/change when doing changes to the
+respective code.
+
+The architecture-agnostic topology definitions are in
+Documentation/cputopology.txt. This file holds x86-specific
+differences/specialities which must not necessarily apply to the generic
+definitions. Thus, the way to read up on Linux topology on x86 is to start
+with the generic one and look at this one in parallel for the x86 specifics.
+
+Needless to say, code should use the generic functions - this file is *only*
+here to *document* the inner workings of x86 topology.
+
+Started by Thomas Gleixner <tglx@linutronix.de> and Borislav Petkov <bp@alien8.de>.
+
+The main aim of the topology facilities is to present adequate interfaces to
+code which needs to know/query/use the structure of the running system wrt
+threads, cores, packages, etc.
+
+The kernel does not care about the concept of physical sockets because a
+socket has no relevance to software. It's an electromechanical component. In
+the past a socket always contained a single package (see below), but with the
+advent of Multi Chip Modules (MCM) a socket can hold more than one package. So
+there might be still references to sockets in the code, but they are of
+historical nature and should be cleaned up.
+
+The topology of a system is described in the units of:
+
+ - packages
+ - cores
+ - threads
+
+* Package:
+
+ Packages contain a number of cores plus shared resources, e.g. DRAM
+ controller, shared caches etc.
+
+ AMD nomenclature for package is 'Node'.
+
+ Package-related topology information in the kernel:
+
+ - cpuinfo_x86.x86_max_cores:
+
+ The number of cores 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
+ and deduced from the APIC IDs of the cores in the package.
+
+ - cpuinfo_x86.logical_id:
+
+ The logical ID of the package. As we do not trust BIOSes to enumerate the
+ packages in a consistent way, we introduced the concept of logical package
+ ID so we can sanely calculate the number of maximum possible packages in
+ the system and have the packages enumerated linearly.
+
+ - topology_max_packages():
+
+ The maximum possible number of packages in the system. Helpful for per
+ package facilities to preallocate per package information.
+
+
+* Cores:
+
+ A core consists of 1 or more threads. It does not matter whether the threads
+ are SMT- or CMT-type threads.
+
+ AMDs nomenclature for a CMT core is "Compute Unit". The kernel always uses
+ "core".
+
+ Core-related topology information in the kernel:
+
+ - smp_num_siblings:
+
+ The number of threads in a core. The number of threads in a package can be
+ calculated by:
+
+ threads_per_package = cpuinfo_x86.x86_max_cores * smp_num_siblings
+
+
+* Threads:
+
+ A thread is a single scheduling unit. It's the equivalent to a logical Linux
+ CPU.
+
+ AMDs nomenclature for CMT threads is "Compute Unit Core". The kernel always
+ uses "thread".
+
+ Thread-related topology information in the kernel:
+
+ - topology_core_cpumask():
+
+ The cpumask contains all online threads in the package to which a thread
+ belongs.
+
+ The number of online threads is also printed in /proc/cpuinfo "siblings."
+
+ - topology_sibling_mask():
+
+ The cpumask contains all online threads in the core to which a thread
+ belongs.
+
+ - topology_logical_package_id():
+
+ The logical package ID to which a thread belongs.
+
+ - topology_physical_package_id():
+
+ The physical package ID to which a thread belongs.
+
+ - topology_core_id();
+
+ The ID of the core to which a thread belongs. It is also printed in /proc/cpuinfo
+ "core_id."
+
+
+
+System topology examples
+
+Note:
+
+The alternative Linux CPU enumeration depends on how the BIOS enumerates the
+threads. Many BIOSes enumerate all threads 0 first and then all threads 1.
+That has the "advantage" that the logical Linux CPU numbers of threads 0 stay
+the same whether threads are enabled or not. That's merely an implementation
+detail and has no practical impact.
+
+1) Single Package, Single Core
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+
+2) Single Package, Dual Core
+
+ a) One thread per core
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+ -> [core 1] -> [thread 0] -> Linux CPU 1
+
+ b) Two threads per core
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+ -> [thread 1] -> Linux CPU 1
+ -> [core 1] -> [thread 0] -> Linux CPU 2
+ -> [thread 1] -> Linux CPU 3
+
+ Alternative enumeration:
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+ -> [thread 1] -> Linux CPU 2
+ -> [core 1] -> [thread 0] -> Linux CPU 1
+ -> [thread 1] -> Linux CPU 3
+
+ AMD nomenclature for CMT systems:
+
+ [node 0] -> [Compute Unit 0] -> [Compute Unit Core 0] -> Linux CPU 0
+ -> [Compute Unit Core 1] -> Linux CPU 1
+ -> [Compute Unit 1] -> [Compute Unit Core 0] -> Linux CPU 2
+ -> [Compute Unit Core 1] -> Linux CPU 3
+
+4) Dual Package, Dual Core
+
+ a) One thread per core
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+ -> [core 1] -> [thread 0] -> Linux CPU 1
+
+ [package 1] -> [core 0] -> [thread 0] -> Linux CPU 2
+ -> [core 1] -> [thread 0] -> Linux CPU 3
+
+ b) Two threads per core
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+ -> [thread 1] -> Linux CPU 1
+ -> [core 1] -> [thread 0] -> Linux CPU 2
+ -> [thread 1] -> Linux CPU 3
+
+ [package 1] -> [core 0] -> [thread 0] -> Linux CPU 4
+ -> [thread 1] -> Linux CPU 5
+ -> [core 1] -> [thread 0] -> Linux CPU 6
+ -> [thread 1] -> Linux CPU 7
+
+ Alternative enumeration:
+
+ [package 0] -> [core 0] -> [thread 0] -> Linux CPU 0
+ -> [thread 1] -> Linux CPU 4
+ -> [core 1] -> [thread 0] -> Linux CPU 1
+ -> [thread 1] -> Linux CPU 5
+
+ [package 1] -> [core 0] -> [thread 0] -> Linux CPU 2
+ -> [thread 1] -> Linux CPU 6
+ -> [core 1] -> [thread 0] -> Linux CPU 3
+ -> [thread 1] -> Linux CPU 7
+
+ AMD nomenclature for CMT systems:
+
+ [node 0] -> [Compute Unit 0] -> [Compute Unit Core 0] -> Linux CPU 0
+ -> [Compute Unit Core 1] -> Linux CPU 1
+ -> [Compute Unit 1] -> [Compute Unit Core 0] -> Linux CPU 2
+ -> [Compute Unit Core 1] -> Linux CPU 3
+
+ [node 1] -> [Compute Unit 0] -> [Compute Unit Core 0] -> Linux CPU 4
+ -> [Compute Unit Core 1] -> Linux CPU 5
+ -> [Compute Unit 1] -> [Compute Unit Core 0] -> Linux CPU 6
+ -> [Compute Unit Core 1] -> Linux CPU 7
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index 049ada8d4e9c..86a9bec18dab 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -369,7 +369,7 @@ static int amd_pmu_cpu_prepare(int cpu)
WARN_ON_ONCE(cpuc->amd_nb);
- if (boot_cpu_data.x86_max_cores < 2)
+ if (!x86_pmu.amd_nb_constraints)
return NOTIFY_OK;
cpuc->amd_nb = amd_alloc_nb(cpu);
@@ -388,7 +388,7 @@ static void amd_pmu_cpu_starting(int cpu)
cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
- if (boot_cpu_data.x86_max_cores < 2)
+ if (!x86_pmu.amd_nb_constraints)
return;
nb_id = amd_get_nb_id(cpu);
@@ -414,7 +414,7 @@ static void amd_pmu_cpu_dead(int cpu)
{
struct cpu_hw_events *cpuhw;
- if (boot_cpu_data.x86_max_cores < 2)
+ if (!x86_pmu.amd_nb_constraints)
return;
cpuhw = &per_cpu(cpu_hw_events, cpu);
@@ -648,6 +648,8 @@ static __initconst const struct x86_pmu amd_pmu = {
.cpu_prepare = amd_pmu_cpu_prepare,
.cpu_starting = amd_pmu_cpu_starting,
.cpu_dead = amd_pmu_cpu_dead,
+
+ .amd_nb_constraints = 1,
};
static int __init amd_core_pmu_init(void)
@@ -674,6 +676,11 @@ static int __init amd_core_pmu_init(void)
x86_pmu.eventsel = MSR_F15H_PERF_CTL;
x86_pmu.perfctr = MSR_F15H_PERF_CTR;
x86_pmu.num_counters = AMD64_NUM_COUNTERS_CORE;
+ /*
+ * AMD Core perfctr has separate MSRs for the NB events, see
+ * the amd/uncore.c driver.
+ */
+ x86_pmu.amd_nb_constraints = 0;
pr_cont("core perfctr, ");
return 0;
@@ -693,6 +700,14 @@ __init int amd_pmu_init(void)
if (ret)
return ret;
+ if (num_possible_cpus() == 1) {
+ /*
+ * No point in allocating data structures to serialize
+ * against other CPUs, when there is only the one CPU.
+ */
+ x86_pmu.amd_nb_constraints = 0;
+ }
+
/* Events are common for all AMDs */
memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index ba6ef18528c9..716d0482f5db 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -608,6 +608,11 @@ struct x86_pmu {
atomic_t lbr_exclusive[x86_lbr_exclusive_max];
/*
+ * AMD bits
+ */
+ unsigned int amd_nb_constraints : 1;
+
+ /*
* Extra registers for events
*/
struct extra_reg *extra_regs;
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 2da46ac16e37..426e946ed0c0 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -190,6 +190,7 @@
#define MSR_PP1_ENERGY_STATUS 0x00000641
#define MSR_PP1_POLICY 0x00000642
+/* Config TDP MSRs */
#define MSR_CONFIG_TDP_NOMINAL 0x00000648
#define MSR_CONFIG_TDP_LEVEL_1 0x00000649
#define MSR_CONFIG_TDP_LEVEL_2 0x0000064A
@@ -210,13 +211,6 @@
#define MSR_GFX_PERF_LIMIT_REASONS 0x000006B0
#define MSR_RING_PERF_LIMIT_REASONS 0x000006B1
-/* Config TDP MSRs */
-#define MSR_CONFIG_TDP_NOMINAL 0x00000648
-#define MSR_CONFIG_TDP_LEVEL1 0x00000649
-#define MSR_CONFIG_TDP_LEVEL2 0x0000064A
-#define MSR_CONFIG_TDP_CONTROL 0x0000064B
-#define MSR_TURBO_ACTIVATION_RATIO 0x0000064C
-
/* Hardware P state interface */
#define MSR_PPERF 0x0000064e
#define MSR_PERF_LIMIT_REASONS 0x0000064f
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 983738ac014c..9264476f3d57 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -132,8 +132,6 @@ struct cpuinfo_x86 {
u16 logical_proc_id;
/* Core id: */
u16 cpu_core_id;
- /* Compute unit id */
- u8 compute_unit_id;
/* Index into per_cpu list: */
u16 cpu_index;
u32 microcode;
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
index 20a3de5cb3b0..66b057306f40 100644
--- a/arch/x86/include/asm/smp.h
+++ b/arch/x86/include/asm/smp.h
@@ -155,6 +155,7 @@ static inline int wbinvd_on_all_cpus(void)
wbinvd();
return 0;
}
+#define smp_num_siblings 1
#endif /* CONFIG_SMP */
extern unsigned disabled_cpus;
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 82866697fcf1..ffae84df8a93 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -276,11 +276,9 @@ static inline bool is_ia32_task(void)
*/
#define force_iret() set_thread_flag(TIF_NOTIFY_RESUME)
-#endif /* !__ASSEMBLY__ */
-
-#ifndef __ASSEMBLY__
extern void arch_task_cache_init(void);
extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
extern void arch_release_task_struct(struct task_struct *tsk);
-#endif
+#endif /* !__ASSEMBLY__ */
+
#endif /* _ASM_X86_THREAD_INFO_H */
diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c
index 29fa475ec518..a147e676fc7b 100644
--- a/arch/x86/kernel/amd_nb.c
+++ b/arch/x86/kernel/amd_nb.c
@@ -170,15 +170,13 @@ int amd_get_subcaches(int cpu)
{
struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
unsigned int mask;
- int cuid;
if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
return 0;
pci_read_config_dword(link, 0x1d4, &mask);
- cuid = cpu_data(cpu).compute_unit_id;
- return (mask >> (4 * cuid)) & 0xf;
+ return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
}
int amd_set_subcaches(int cpu, unsigned long mask)
@@ -204,7 +202,7 @@ int amd_set_subcaches(int cpu, unsigned long mask)
pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
}
- cuid = cpu_data(cpu).compute_unit_id;
+ cuid = cpu_data(cpu).cpu_core_id;
mask <<= 4 * cuid;
mask |= (0xf ^ (1 << cuid)) << 26;
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 6e47e3a916f1..7b76eb67a9b3 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -300,7 +300,6 @@ static int nearby_node(int apicid)
#ifdef CONFIG_SMP
static void amd_get_topology(struct cpuinfo_x86 *c)
{
- u32 cores_per_cu = 1;
u8 node_id;
int cpu = smp_processor_id();
@@ -313,8 +312,8 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
/* get compute unit information */
smp_num_siblings = ((ebx >> 8) & 3) + 1;
- c->compute_unit_id = ebx & 0xff;
- cores_per_cu += ((ebx >> 8) & 3);
+ c->x86_max_cores /= smp_num_siblings;
+ c->cpu_core_id = ebx & 0xff;
} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
u64 value;
@@ -325,19 +324,16 @@ static void amd_get_topology(struct cpuinfo_x86 *c)
/* fixup multi-node processor information */
if (nodes_per_socket > 1) {
- u32 cores_per_node;
u32 cus_per_node;
set_cpu_cap(c, X86_FEATURE_AMD_DCM);
- cores_per_node = c->x86_max_cores / nodes_per_socket;
- cus_per_node = cores_per_node / cores_per_cu;
+ cus_per_node = c->x86_max_cores / nodes_per_socket;
/* store NodeID, use llc_shared_map to store sibling info */
per_cpu(cpu_llc_id, cpu) = node_id;
/* core id has to be in the [0 .. cores_per_node - 1] range */
- c->cpu_core_id %= cores_per_node;
- c->compute_unit_id %= cus_per_node;
+ c->cpu_core_id %= cus_per_node;
}
}
#endif
diff --git a/arch/x86/kernel/cpu/powerflags.c b/arch/x86/kernel/cpu/powerflags.c
index 31f0f335ed22..1dd8294fd730 100644
--- a/arch/x86/kernel/cpu/powerflags.c
+++ b/arch/x86/kernel/cpu/powerflags.c
@@ -18,4 +18,6 @@ const char *const x86_power_flags[32] = {
"", /* tsc invariant mapped to constant_tsc */
"cpb", /* core performance boost */
"eff_freq_ro", /* Readonly aperf/mperf */
+ "proc_feedback", /* processor feedback interface */
+ "acc_power", /* accumulated power mechanism */
};
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index b2c99f811c3f..a2065d3b3b39 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -422,7 +422,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
if (c->phys_proc_id == o->phys_proc_id &&
per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2) &&
- c->compute_unit_id == o->compute_unit_id)
+ c->cpu_core_id == o->cpu_core_id)
return topology_sane(c, o, "smt");
} else if (c->phys_proc_id == o->phys_proc_id &&
diff --git a/arch/x86/ras/mce_amd_inj.c b/arch/x86/ras/mce_amd_inj.c
index 55d38cfa46c2..9e02dcaef683 100644
--- a/arch/x86/ras/mce_amd_inj.c
+++ b/arch/x86/ras/mce_amd_inj.c
@@ -20,6 +20,7 @@
#include <linux/pci.h>
#include <asm/mce.h>
+#include <asm/smp.h>
#include <asm/amd_nb.h>
#include <asm/irq_vectors.h>
@@ -206,7 +207,7 @@ static u32 get_nbc_for_node(int node_id)
struct cpuinfo_x86 *c = &boot_cpu_data;
u32 cores_per_node;
- cores_per_node = c->x86_max_cores / amd_get_nodes_per_socket();
+ cores_per_node = (c->x86_max_cores * smp_num_siblings) / amd_get_nodes_per_socket();
return cores_per_node * node_id;
}