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Portable Hardware Locality (hwloc) Documentation: v2.0.3

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Object Types

Macros

#define HWLOC_OBJ_TYPE_MIN   HWLOC_OBJ_MACHINE
 

Typedefs

typedef enum hwloc_obj_cache_type_e hwloc_obj_cache_type_t
 
typedef enum hwloc_obj_bridge_type_e hwloc_obj_bridge_type_t
 
typedef enum hwloc_obj_osdev_type_e hwloc_obj_osdev_type_t
 

Enumerations

enum  hwloc_obj_type_t {
  HWLOC_OBJ_MACHINE, HWLOC_OBJ_PACKAGE, HWLOC_OBJ_CORE, HWLOC_OBJ_PU,
  HWLOC_OBJ_L1CACHE, HWLOC_OBJ_L2CACHE, HWLOC_OBJ_L3CACHE, HWLOC_OBJ_L4CACHE,
  HWLOC_OBJ_L5CACHE, HWLOC_OBJ_L1ICACHE, HWLOC_OBJ_L2ICACHE, HWLOC_OBJ_L3ICACHE,
  HWLOC_OBJ_GROUP, HWLOC_OBJ_NUMANODE, HWLOC_OBJ_BRIDGE, HWLOC_OBJ_PCI_DEVICE,
  HWLOC_OBJ_OS_DEVICE, HWLOC_OBJ_MISC
}
 
enum  hwloc_obj_cache_type_e { HWLOC_OBJ_CACHE_UNIFIED, HWLOC_OBJ_CACHE_DATA, HWLOC_OBJ_CACHE_INSTRUCTION }
 
enum  hwloc_obj_bridge_type_e { HWLOC_OBJ_BRIDGE_HOST, HWLOC_OBJ_BRIDGE_PCI }
 
enum  hwloc_obj_osdev_type_e {
  HWLOC_OBJ_OSDEV_BLOCK, HWLOC_OBJ_OSDEV_GPU, HWLOC_OBJ_OSDEV_NETWORK, HWLOC_OBJ_OSDEV_OPENFABRICS,
  HWLOC_OBJ_OSDEV_DMA, HWLOC_OBJ_OSDEV_COPROC
}
 
enum  hwloc_compare_types_e { HWLOC_TYPE_UNORDERED }
 

Functions

int hwloc_compare_types (hwloc_obj_type_t type1, hwloc_obj_type_t type2)
 

Detailed Description

Macro Definition Documentation

◆ HWLOC_OBJ_TYPE_MIN

#define HWLOC_OBJ_TYPE_MIN   HWLOC_OBJ_MACHINE

Type of topology object.

Note
Do not rely on the ordering or completeness of the values as new ones may be defined in the future! If you need to compare types, use hwloc_compare_types() instead.Sentinel value

Typedef Documentation

◆ hwloc_obj_bridge_type_t

Type of one side (upstream or downstream) of an I/O bridge.

◆ hwloc_obj_cache_type_t

◆ hwloc_obj_osdev_type_t

Type of a OS device.

Enumeration Type Documentation

◆ hwloc_compare_types_e

Enumerator
HWLOC_TYPE_UNORDERED 

Value returned by hwloc_compare_types() when types can not be compared.

◆ hwloc_obj_bridge_type_e

Type of one side (upstream or downstream) of an I/O bridge.

Enumerator
HWLOC_OBJ_BRIDGE_HOST 

Host-side of a bridge, only possible upstream.

HWLOC_OBJ_BRIDGE_PCI 

PCI-side of a bridge.

◆ hwloc_obj_cache_type_e

Cache type.

Enumerator
HWLOC_OBJ_CACHE_UNIFIED 

Unified cache.

HWLOC_OBJ_CACHE_DATA 

Data cache.

HWLOC_OBJ_CACHE_INSTRUCTION 

Instruction cache (filtered out by default).

◆ hwloc_obj_osdev_type_e

Type of a OS device.

Enumerator
HWLOC_OBJ_OSDEV_BLOCK 

Operating system block device. For instance "sda" on Linux.

HWLOC_OBJ_OSDEV_GPU 

Operating system GPU device. For instance ":0.0" for a GL display, "card0" for a Linux DRM device.

HWLOC_OBJ_OSDEV_NETWORK 

Operating system network device. For instance the "eth0" interface on Linux.

HWLOC_OBJ_OSDEV_OPENFABRICS 

Operating system openfabrics device. For instance the "mlx4_0" InfiniBand HCA, or "hfi1_0" Omni-Path interface on Linux.

HWLOC_OBJ_OSDEV_DMA 

Operating system dma engine device. For instance the "dma0chan0" DMA channel on Linux.

HWLOC_OBJ_OSDEV_COPROC 

Operating system co-processor device. For instance "mic0" for a Xeon Phi (MIC) on Linux, "opencl0d0" for a OpenCL device, "cuda0" for a CUDA device.

◆ hwloc_obj_type_t

Enumerator
HWLOC_OBJ_MACHINE 

Machine. A set of processors and memory with cache coherency.

This type is always used for the root object of a topology, and never used anywhere else. Hence its parent is always NULL.

HWLOC_OBJ_PACKAGE 

Physical package. The physical package that usually gets inserted into a socket on the motherboard. A processor package usually contains multiple cores.

HWLOC_OBJ_CORE 

Core. A computation unit (may be shared by several logical processors).

HWLOC_OBJ_PU 

Processing Unit, or (Logical) Processor. An execution unit (may share a core with some other logical processors, e.g. in the case of an SMT core).

This is the smallest object representing CPU resources, it cannot have any child except Misc objects.

Objects of this kind are always reported and can thus be used as fallback when others are not.

HWLOC_OBJ_L1CACHE 

Level 1 Data (or Unified) Cache.

HWLOC_OBJ_L2CACHE 

Level 2 Data (or Unified) Cache.

HWLOC_OBJ_L3CACHE 

Level 3 Data (or Unified) Cache.

HWLOC_OBJ_L4CACHE 

Level 4 Data (or Unified) Cache.

HWLOC_OBJ_L5CACHE 

Level 5 Data (or Unified) Cache.

HWLOC_OBJ_L1ICACHE 

Level 1 instruction Cache (filtered out by default).

HWLOC_OBJ_L2ICACHE 

Level 2 instruction Cache (filtered out by default).

HWLOC_OBJ_L3ICACHE 

Level 3 instruction Cache (filtered out by default).

HWLOC_OBJ_GROUP 

Group objects. Objects which do not fit in the above but are detected by hwloc and are useful to take into account for affinity. For instance, some operating systems expose their arbitrary processors aggregation this way. And hwloc may insert such objects to group NUMA nodes according to their distances. See also What are these Group objects in my topology?.

These objects are removed when they do not bring any structure.

HWLOC_OBJ_NUMANODE 

NUMA node. An object that contains memory that is directly and byte-accessible to the host processors. It is usually close to some cores (the corresponding objects are descendants of the NUMA node object in the hwloc tree).

There is always at one such object in the topology even if the machine is not NUMA.

Memory objects are not listed in the main children list, but rather in the dedicated Memory children list.

NUMA nodes have a special depth HWLOC_TYPE_DEPTH_NUMANODE instead of a normal depth just like other objects in the main tree.

HWLOC_OBJ_BRIDGE 

Bridge (filtered out by default). Any bridge that connects the host or an I/O bus, to another I/O bus. They are not added to the topology unless I/O discovery is enabled with hwloc_topology_set_flags(). I/O objects are not listed in the main children list, but rather in the dedicated io children list. I/O objects have NULL CPU and node sets.

HWLOC_OBJ_PCI_DEVICE 

PCI device (filtered out by default). They are not added to the topology unless I/O discovery is enabled with hwloc_topology_set_flags(). I/O objects are not listed in the main children list, but rather in the dedicated io children list. I/O objects have NULL CPU and node sets.

HWLOC_OBJ_OS_DEVICE 

Operating system device (filtered out by default). They are not added to the topology unless I/O discovery is enabled with hwloc_topology_set_flags(). I/O objects are not listed in the main children list, but rather in the dedicated io children list. I/O objects have NULL CPU and node sets.

HWLOC_OBJ_MISC 

Miscellaneous objects (filtered out by default). Objects without particular meaning, that can e.g. be added by the application for its own use, or by hwloc for miscellaneous objects such as MemoryModule (DIMMs). These objects are not listed in the main children list, but rather in the dedicated misc children list. Misc objects may only have Misc objects as children, and those are in the dedicated misc children list as well. Misc objects have NULL CPU and node sets.

Function Documentation

◆ hwloc_compare_types()

int hwloc_compare_types ( hwloc_obj_type_t  type1,
hwloc_obj_type_t  type2 
)

Compare the depth of two object types.

Types shouldn't be compared as they are, since newer ones may be added in the future. This function returns less than, equal to, or greater than zero respectively if type1 objects usually include type2 objects, are the same as type2 objects, or are included in type2 objects. If the types can not be compared (because neither is usually contained in the other), HWLOC_TYPE_UNORDERED is returned. Object types containing CPUs can always be compared (usually, a system contains machines which contain nodes which contain packages which contain caches, which contain cores, which contain processors).

Note
HWLOC_OBJ_PU will always be the deepest, while HWLOC_OBJ_MACHINE is always the highest.
This does not mean that the actual topology will respect that order: e.g. as of today cores may also contain caches, and packages may also contain nodes. This is thus just to be seen as a fallback comparison method.