Hardware Locality (hwloc)
1.7.2
|
Data Structures | |
struct | hwloc_topology_discovery_support |
struct | hwloc_topology_cpubind_support |
struct | hwloc_topology_membind_support |
struct | hwloc_topology_support |
These functions can optionally be called between hwloc_topology_init() and hwloc_topology_load() to configure how the detection should be performed, e.g. to ignore some objects types, define a synthetic topology, etc.
If none of them is called, the default is to detect all the objects of the machine that the caller is allowed to access.
This default behavior may also be modified through environment variables if the application did not modify it already. Setting HWLOC_XMLFILE in the environment enforces the discovery from a XML file as if hwloc_topology_set_xml() had been called. HWLOC_FSROOT switches to reading the topology from the specified Linux filesystem root as if hwloc_topology_set_fsroot() had been called. Finally, HWLOC_THISSYSTEM enforces the return value of hwloc_topology_is_thissystem().
Flags to be set onto a topology context before load.
Flags should be given to hwloc_topology_set_flags(). They may also be returned by hwloc_topology_get_flags().
struct hwloc_topology_support* hwloc_topology_get_support | ( | hwloc_topology_t restrict | topology) |
Retrieve the topology support.
int hwloc_topology_ignore_all_keep_structure | ( | hwloc_topology_t | topology) |
Ignore all objects that do not bring any structure.
Ignore all objects that do not bring any structure: Each ignored object should have a single children or be the only child of its parent. I/O objects may not be ignored, topology flags should be used to configure their discovery instead.
int hwloc_topology_ignore_type | ( | hwloc_topology_t | topology, |
hwloc_obj_type_t | type | ||
) |
Ignore an object type.
Ignore all objects from the given type. The bottom-level type HWLOC_OBJ_PU may not be ignored. The top-level object of the hierarchy will never be ignored, even if this function succeeds. I/O objects may not be ignored, topology flags should be used to configure their discovery instead.
int hwloc_topology_ignore_type_keep_structure | ( | hwloc_topology_t | topology, |
hwloc_obj_type_t | type | ||
) |
Ignore an object type if it does not bring any structure.
Ignore all objects from the given type as long as they do not bring any structure: Each ignored object should have a single children or be the only child of its parent. The bottom-level type HWLOC_OBJ_PU may not be ignored. I/O objects may not be ignored, topology flags should be used to configure their discovery instead.
int hwloc_topology_set_custom | ( | hwloc_topology_t | topology) |
Prepare the topology for custom assembly.
The topology then contains a single root object. It must then be built by inserting other topologies with hwloc_custom_insert_topology() or single objects with hwloc_custom_insert_group_object_by_parent(). hwloc_topology_load() must be called to finalize the new topology as usual.
int hwloc_topology_set_distance_matrix | ( | hwloc_topology_t restrict | topology, |
hwloc_obj_type_t | type, | ||
unsigned | nbobjs, | ||
unsigned * | os_index, | ||
float * | distances | ||
) |
Provide a distance matrix.
Provide the matrix of distances between a set of objects of the given type. The set may or may not contain all the existing objects of this type. The objects are specified by their OS/physical index in the os_index
array. The distances
matrix follows the same order. The distance from object i to object j in the i*nbobjs+j.
A single latency matrix may be defined for each type. If another distance matrix already exists for the given type, either because the user specified it or because the OS offers it, it will be replaced by the given one. If nbobjs
is 0
, os_index
is NULL
and distances
is NULL
, the existing distance matrix for the given type is removed.
int hwloc_topology_set_flags | ( | hwloc_topology_t | topology, |
unsigned long | flags | ||
) |
Set OR'ed flags to non-yet-loaded topology.
Set a OR'ed set of hwloc_topology_flags_e onto a topology that was not yet loaded.
If this function is called multiple times, the last invokation will erase and replace the set of flags that was previously set.
The flags set in a topology may be retrieved with hwloc_topology_get_flags()
int hwloc_topology_set_fsroot | ( | hwloc_topology_t restrict | topology, |
const char *restrict | fsroot_path | ||
) |
Change the file-system root path when building the topology from sysfs/procfs.
On Linux system, use sysfs and procfs files as if they were mounted on the given fsroot_path
instead of the main file-system root. Setting the environment variable HWLOC_FSROOT may also result in this behavior. Not using the main file-system root causes hwloc_topology_is_thissystem() to return 0.
Note that this function does not actually load topology information; it just tells hwloc where to load it from. You'll still need to invoke hwloc_topology_load() to actually load the topology information.
fsroot_path
cannot be used.int hwloc_topology_set_pid | ( | hwloc_topology_t restrict | topology, |
hwloc_pid_t | pid | ||
) |
Change which pid the topology is viewed from.
On some systems, processes may have different views of the machine, for instance the set of allowed CPUs. By default, hwloc exposes the view from the current process. Calling hwloc_topology_set_pid() permits to make it expose the topology of the machine from the point of view of another process.
hwloc_pid_t
is pid_t
on Unix platforms, and HANDLE
on native Windows platforms.int hwloc_topology_set_synthetic | ( | hwloc_topology_t restrict | topology, |
const char *restrict | description | ||
) |
Enable synthetic topology.
Gather topology information from the given description
, a space-separated string of numbers describing the arity of each level. Each number may be prefixed with a type and a colon to enforce the type of a level. If only some level types are enforced, hwloc will try to choose the other types according to usual topologies, but it may fail and you may have to specify more level types manually. See also the synthetic.
If description
was properly parsed and describes a valid topology configuration, this function returns 0. Otherwise -1 is returned and errno is set to EINVAL.
Note that this function does not actually load topology information; it just tells hwloc where to load it from. You'll still need to invoke hwloc_topology_load() to actually load the topology information.
int hwloc_topology_set_xml | ( | hwloc_topology_t restrict | topology, |
const char *restrict | xmlpath | ||
) |
Enable XML-file based topology.
Gather topology information from the XML file given at xmlpath
. Setting the environment variable HWLOC_XMLFILE may also result in this behavior. This file may have been generated earlier with hwloc_topology_export_xml() or lstopo file.xml.
Note that this function does not actually load topology information; it just tells hwloc where to load it from. You'll still need to invoke hwloc_topology_load() to actually load the topology information.
int hwloc_topology_set_xmlbuffer | ( | hwloc_topology_t restrict | topology, |
const char *restrict | buffer, | ||
int | size | ||
) |
Enable XML based topology using a memory buffer (instead of a file, as with hwloc_topology_set_xml()).
Gather topology information from the XML memory buffer given at buffer
and of length size
. This buffer may have been filled earlier with hwloc_topology_export_xmlbuffer().
Note that this function does not actually load topology information; it just tells hwloc where to load it from. You'll still need to invoke hwloc_topology_load() to actually load the topology information.