CPU information module

Classes
struct	CacheLevel
	Structure describing a cache level. More...
struct	CpuInfo
	Structure with general CPU information. More...
struct	CpuTopology
	Structure describing the topology of the HW threads in the system. More...
struct	HWThread
	Structure with IDs of a HW thread. More...
struct	treeNode
	Structure of a tree node. More...

Typedefs
typedef CpuInfo *	CpuInfo_t
	Pointer for exporting the CpuInfo data structure.
typedef CpuTopology *	CpuTopology_t
	Pointer for exporting the CpuTopology data structure.
typedef struct treeNode	TreeNode
	Shorter name for struct treeNode.

Enumerations
enum	CacheType {   NOCACHE =0, DATACACHE, INSTRUCTIONCACHE, UNIFIEDCACHE,   ITLB, DTLB }
	Enum of possible caches. More...
enum	FeatureBit {   SSE3 =0, MMX, SSE, SSE2,   MONITOR, ACPI, RDTSCP, VMX,   EIST, TM, TM2, AES,   RDRAND, SSSE3, SSE41, SSE42,   AVX, FMA, AVX2, RTM,   HLE, HTT, RDSEED, AVX512,   SWP, VFP, NEON, EDSP,   VFPV3, VFPV4, TLS }
	Enum of possible CPU features. More...

Functions
CpuInfo_t	get_cpuInfo (void) __attribute__((visibility("default")))
	Retrieve CPU information of the current machine. More...
CpuTopology_t	get_cpuTopology (void) __attribute__((visibility("default")))
	Retrieve CPU topology of the current machine. More...
void	print_supportedCPUs (void) __attribute__((visibility("default")))
	Print all supported architectures.
void	topology_finalize (void) __attribute__((visibility("default")))
	Destroy topology structures CpuInfo_t and CpuTopology_t. More...
int	topology_init (void) __attribute__((visibility("default")))
	Initialize topology information. More...

Variables
CpuInfo	cpuid_info
	Variable holding the global cpu information structure.
CpuTopology	cpuid_topology
	Variable holding the global cpu topology structure.

Detailed Description

Enumeration Type Documentation

enum CacheType

Enum of possible caches.

CPU caches can have different tasks and hold different kind of data. This enum lists all shapes used in all supported CPUs

Enumerator
NOCACHE	No cache used as undef value.
DATACACHE	Cache holding data cache lines.
INSTRUCTIONCACHE	Cache holding instruction cache lines.
UNIFIEDCACHE	Cache holding both instruction and data cache lines.
ITLB	Translation Lookaside Buffer cache for instruction pages.
DTLB	Translation Lookaside Buffer cache for data pages.

enum FeatureBit

Enum of possible CPU features.

CPUs implement different features that likely improve application performance if optimized using the feature. The list contains all features that are currently supported by LIKWID. LIKWID does not perform any action based on these features, it gathers the data only for output purposes. It is not a complete list.

Enumerator
SSE3	Streaming SIMD Extensions 3.
MMX	Multi Media Extension.
SSE	Streaming SIMD Extensions.
SSE2	Streaming SIMD Extensions 2.
MONITOR	MONITOR and MWAIT instructions (part of SSE3)
ACPI	Advanced Configuration and Power Interface.
RDTSCP	Serializing Read of the Time Stamp Counter.
VMX	Virtual Machine eXtensions (VT-x)
EIST	Enhanced Intel SpeedStep.
TM	Thermal Monitor.
TM2	Thermal Monitor 2.
AES	AES instruction set.
RDRAND	Random numbers from an on-chip hardware random number generator.
SSSE3	Supplemental Streaming SIMD Extensions 3.
SSE41	Streaming SIMD Extensions 4.1.
SSE42	Streaming SIMD Extensions 4.2.
AVX	Advanced Vector Extensions.
FMA	Fused multiply-add (FMA3)
AVX2	Advanced Vector Extensions 2.
RTM	Restricted Transactional Memory.
HLE	Hardware Lock Elision.
HTT	Hyper-Threading Technology.
RDSEED	Non-deterministic random bit generator.
AVX512	512-bit wide vector registers for Advanced Vector Extensions
SWP	Atomic read-modify-write.
VFP	First generation SIMD.
NEON	Second generation SIMD.
EDSP	DSP extensions.
VFPV3	First generation SIMD Version 3.
VFPV4	First generation SIMD Version 4.
TLS	Thread-local storage registers.

Function Documentation

CpuInfo_t get_cpuInfo

(

void

)

Retrieve CPU information of the current machine.

Get the previously initialized CPU info structure containing number of CPUs/Threads

See also

CpuInfo_t

Returns

CpuInfo_t (pointer to internal cpuid_info structure)

CpuTopology_t get_cpuTopology

(

void

)

Retrieve CPU topology of the current machine.

See also

CpuTopology_t

Returns

CpuTopology_t (pointer to internal cpuid_topology structure)

void topology_finalize

(

void

)

Destroy topology structures CpuInfo_t and CpuTopology_t.

Retrieved pointers to the structures are not valid anymore after this function call

See also

CpuInfo_t and CpuTopology_t

int topology_init

(

void

)

Initialize topology information.

CpuInfo_t and CpuTopology_t are initialized by either HWLOC, CPUID/ProcFS or topology file if present. The topology file name can be configured in the configuration file. Furthermore, the paths /etc/likwid_topo.cfg and <PREFIX>/etc/likwid_topo.cfg are checked.

See also

CpuInfo_t and CpuTopology_t

Returns

always 0