/*
* Copyright © 2013-2022 Inria. All rights reserved.
* Copyright © 2016 Cisco Systems, Inc. All rights reserved.
* See COPYING in top-level directory.
*/
#ifndef HWLOC_PLUGINS_H
#define HWLOC_PLUGINS_H
/** \file
* \brief Public interface for building hwloc plugins.
*/
struct hwloc_backend;
#include "hwloc.h"
#ifdef HWLOC_INSIDE_PLUGIN
/* needed for hwloc_plugin_check_namespace() */
#ifdef HWLOC_HAVE_LTDL
#include <ltdl.h>
#else
#include <dlfcn.h>
#endif
#endif
/** \defgroup hwlocality_disc_components Components and Plugins: Discovery components
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Discovery component structure
*
* This is the major kind of components, taking care of the discovery.
* They are registered by generic components, either statically-built or as plugins.
*/
struct hwloc_disc_component {
/** \brief Name.
* If this component is built as a plugin, this name does not have to match the plugin filename.
*/
const char *name;
/** \brief Discovery phases performed by this component.
* OR'ed set of ::hwloc_disc_phase_t
*/
unsigned phases;
/** \brief Component phases to exclude, as an OR'ed set of ::hwloc_disc_phase_t.
*
* For a GLOBAL component, this usually includes all other phases (\c ~UL).
*
* Other components only exclude types that may bring conflicting
* topology information. MISC components should likely not be excluded
* since they usually bring non-primary additional information.
*/
unsigned excluded_phases;
/** \brief Instantiate callback to create a backend from the component.
* Parameters data1, data2, data3 are NULL except for components
* that have special enabling routines such as hwloc_topology_set_xml(). */
struct hwloc_backend * (*instantiate)(struct hwloc_topology *topology, struct hwloc_disc_component *component, unsigned excluded_phases, const void *data1, const void *data2, const void *data3);
/** \brief Component priority.
* Used to sort topology->components, higher priority first.
* Also used to decide between two components with the same name.
*
* Usual values are
* 50 for native OS (or platform) components,
* 45 for x86,
* 40 for no-OS fallback,
* 30 for global components (xml, synthetic),
* 20 for pci,
* 10 for other misc components (opencl etc.).
*/
unsigned priority;
/** \brief Enabled by default.
* If unset, if will be disabled unless explicitly requested.
*/
unsigned enabled_by_default;
/** \private Used internally to list components by priority on topology->components
* (the component structure is usually read-only,
* the core copies it before using this field for queueing)
*/
struct hwloc_disc_component * next;
};
/** @} */
/** \defgroup hwlocality_disc_backends Components and Plugins: Discovery backends
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Discovery phase */
typedef enum hwloc_disc_phase_e {
/** \brief xml or synthetic, platform-specific components such as bgq.
* Discovers everything including CPU, memory, I/O and everything else.
* A component with a Global phase usually excludes all other phases.
* \hideinitializer */
HWLOC_DISC_PHASE_GLOBAL = (1U<<0),
/** \brief CPU discovery.
* \hideinitializer */
HWLOC_DISC_PHASE_CPU = (1U<<1),
/** \brief Attach memory to existing CPU objects.
* \hideinitializer */
HWLOC_DISC_PHASE_MEMORY = (1U<<2),
/** \brief Attach PCI devices and bridges to existing CPU objects.
* \hideinitializer */
HWLOC_DISC_PHASE_PCI = (1U<<3),
/** \brief I/O discovery that requires PCI devices (OS devices such as OpenCL, CUDA, etc.).
* \hideinitializer */
HWLOC_DISC_PHASE_IO = (1U<<4),
/** \brief Misc objects that gets added below anything else.
* \hideinitializer */
HWLOC_DISC_PHASE_MISC = (1U<<5),
/** \brief Annotating existing objects, adding distances, etc.
* \hideinitializer */
HWLOC_DISC_PHASE_ANNOTATE = (1U<<6),
/** \brief Final tweaks to a ready-to-use topology.
* This phase runs once the topology is loaded, before it is returned to the topology.
* Hence it may only use the main hwloc API for modifying the topology,
* for instance by restricting it, adding info attributes, etc.
* \hideinitializer */
HWLOC_DISC_PHASE_TWEAK = (1U<<7)
} hwloc_disc_phase_t;
/** \brief Discovery status flags */
enum hwloc_disc_status_flag_e {
/** \brief The sets of allowed resources were already retrieved \hideinitializer */
HWLOC_DISC_STATUS_FLAG_GOT_ALLOWED_RESOURCES = (1UL<<1)
};
/** \brief Discovery status structure
*
* Used by the core and backends to inform about what has been/is being done
* during the discovery process.
*/
struct hwloc_disc_status {
/** \brief The current discovery phase that is performed.
* Must match one of the phases in the component phases field.
*/
hwloc_disc_phase_t phase;
/** \brief Dynamically excluded phases.
* If a component decides during discovery that some phases are no longer needed.
*/
unsigned excluded_phases;
/** \brief OR'ed set of ::hwloc_disc_status_flag_e */
unsigned long flags;
};
/** \brief Discovery backend structure
*
* A backend is the instantiation of a discovery component.
* When a component gets enabled for a topology,
* its instantiate() callback creates a backend.
*
* hwloc_backend_alloc() initializes all fields to default values
* that the component may change (except "component" and "next")
* before enabling the backend with hwloc_backend_enable().
*
* Most backends assume that the topology is_thissystem flag is
* set because they talk to the underlying operating system.
* However they may still be used in topologies without the
* is_thissystem flag for debugging reasons.
* In practice, they are usually auto-disabled in such cases
* (excluded by xml or synthetic backends, or by environment
* variables when changing the Linux fsroot or the x86 cpuid path).
*/
struct hwloc_backend {
/** \private Reserved for the core, set by hwloc_backend_alloc() */
struct hwloc_disc_component * component;
/** \private Reserved for the core, set by hwloc_backend_enable() */
struct hwloc_topology * topology;
/** \private Reserved for the core. Set to 1 if forced through envvar, 0 otherwise. */
int envvar_forced;
/** \private Reserved for the core. Used internally to list backends topology->backends. */
struct hwloc_backend * next;
/** \brief Discovery phases performed by this component, possibly without some of them if excluded by other components.
* OR'ed set of ::hwloc_disc_phase_t
*/
unsigned phases;
/** \brief Backend flags, currently always 0. */
unsigned long flags;
/** \brief Backend-specific 'is_thissystem' property.
* Set to 0 if the backend disables the thissystem flag for this topology
* (e.g. loading from xml or synthetic string,
* or using a different fsroot on Linux, or a x86 CPUID dump).
* Set to -1 if the backend doesn't care (default).
*/
int is_thissystem;
/** \brief Backend private data, or NULL if none. */
void * private_data;
/** \brief Callback for freeing the private_data.
* May be NULL.
*/
void (*disable)(struct hwloc_backend *backend);
/** \brief Main discovery callback.
* returns -1 on error, either because it couldn't add its objects ot the existing topology,
* or because of an actual discovery/gathering failure.
* May be NULL.
*/
int (*discover)(struct hwloc_backend *backend, struct hwloc_disc_status *status);
/** \brief Callback to retrieve the locality of a PCI object.
* Called by the PCI core when attaching PCI hierarchy to CPU objects.
* May be NULL.
*/
int (*get_pci_busid_cpuset)(struct hwloc_backend *backend, struct hwloc_pcidev_attr_s *busid, hwloc_bitmap_t cpuset);
};
/** \brief Allocate a backend structure, set good default values, initialize backend->component and topology, etc.
* The caller will then modify whatever needed, and call hwloc_backend_enable().
*/
HWLOC_DECLSPEC struct hwloc_backend * hwloc_backend_alloc(struct hwloc_topology *topology, struct hwloc_disc_component *component);
/** \brief Enable a previously allocated and setup backend. */
HWLOC_DECLSPEC int hwloc_backend_enable(struct hwloc_backend *backend);
/** @} */
/** \defgroup hwlocality_generic_components Components and Plugins: Generic components
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Generic component type */
typedef enum hwloc_component_type_e {
/** \brief The data field must point to a struct hwloc_disc_component. */
HWLOC_COMPONENT_TYPE_DISC,
/** \brief The data field must point to a struct hwloc_xml_component. */
HWLOC_COMPONENT_TYPE_XML
} hwloc_component_type_t;
/** \brief Generic component structure
*
* Generic components structure, either statically listed by configure in static-components.h
* or dynamically loaded as a plugin.
*/
struct hwloc_component {
/** \brief Component ABI version, set to ::HWLOC_COMPONENT_ABI */
unsigned abi;
/** \brief Process-wide component initialization callback.
*
* This optional callback is called when the component is registered
* to the hwloc core (after loading the plugin).
*
* When the component is built as a plugin, this callback
* should call hwloc_check_plugin_namespace()
* and return an negative error code on error.
*
* \p flags is always 0 for now.
*
* \return 0 on success, or a negative code on error.
*
* \note If the component uses ltdl for loading its own plugins,
* it should load/unload them only in init() and finalize(),
* to avoid race conditions with hwloc's use of ltdl.
*/
int (*init)(unsigned long flags);
/** \brief Process-wide component termination callback.
*
* This optional callback is called after unregistering the component
* from the hwloc core (before unloading the plugin).
*
* \p flags is always 0 for now.
*
* \note If the component uses ltdl for loading its own plugins,
* it should load/unload them only in init() and finalize(),
* to avoid race conditions with hwloc's use of ltdl.
*/
void (*finalize)(unsigned long flags);
/** \brief Component type */
hwloc_component_type_t type;
/** \brief Component flags, unused for now */
unsigned long flags;
/** \brief Component data, pointing to a struct hwloc_disc_component or struct hwloc_xml_component. */
void * data;
};
/** @} */
/** \defgroup hwlocality_components_core_funcs Components and Plugins: Core functions to be used by components
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Check whether error messages are hidden.
*
* Callers should print critical error messages
* (e.g. invalid hw topo info, invalid config)
* only if this function returns strictly less than 2.
*
* Callers should print non-critical error messages
* (e.g. failure to initialize CUDA)
* if this function returns 0.
*
* This function return 1 by default (show critical only),
* 0 in lstopo (show all),
* or anything set in HWLOC_HIDE_ERRORS in the environment.
*
* Use macros HWLOC_SHOW_CRITICAL_ERRORS() and HWLOC_SHOW_ALL_ERRORS()
* for clarity.
*/
HWLOC_DECLSPEC int hwloc_hide_errors(void);
#define HWLOC_SHOW_CRITICAL_ERRORS() (hwloc_hide_errors() < 2)
#define HWLOC_SHOW_ALL_ERRORS() (hwloc_hide_errors() == 0)
/** \brief Add an object to the topology.
*
* Insert new object \p obj in the topology starting under existing object \p root
* (if \c NULL, the topology root object is used).
*
* It is sorted along the tree of other objects according to the inclusion of
* cpusets, to eventually be added as a child of the smallest object including
* this object.
*
* If the cpuset is empty, the type of the object (and maybe some attributes)
* must be enough to find where to insert the object. This is especially true
* for NUMA nodes with memory and no CPUs.
*
* The given object should not have children.
*
* This shall only be called before levels are built.
*
* The caller should check whether the object type is filtered-out before calling this function.
*
* The topology cpuset/nodesets will be enlarged to include the object sets.
*
* \p reason is a unique string identifying where and why this insertion call was performed
* (it will be displayed in case of internal insertion error).
*
* Returns the object on success.
* Returns NULL and frees obj on error.
* Returns another object and frees obj if it was merged with an identical pre-existing object.
*/
HWLOC_DECLSPEC hwloc_obj_t
hwloc__insert_object_by_cpuset(struct hwloc_topology *topology, hwloc_obj_t root,
hwloc_obj_t obj, const char *reason);
/** \brief Insert an object somewhere in the topology.
*
* It is added as the last child of the given parent.
* The cpuset is completely ignored, so strange objects such as I/O devices should
* preferably be inserted with this.
*
* When used for "normal" children with cpusets (when importing from XML
* when duplicating a topology), the caller should make sure that:
* - children are inserted in order,
* - children cpusets do not intersect.
*
* The given object may have normal, I/O or Misc children, as long as they are in order as well.
* These children must have valid parent and next_sibling pointers.
*
* The caller should check whether the object type is filtered-out before calling this function.
*/
HWLOC_DECLSPEC void hwloc_insert_object_by_parent(struct hwloc_topology *topology, hwloc_obj_t parent, hwloc_obj_t obj);
/** \brief Allocate and initialize an object of the given type and physical index.
*
* If \p os_index is unknown or irrelevant, use \c HWLOC_UNKNOWN_INDEX.
*/
HWLOC_DECLSPEC hwloc_obj_t hwloc_alloc_setup_object(hwloc_topology_t topology, hwloc_obj_type_t type, unsigned os_index);
/** \brief Setup object cpusets/nodesets by OR'ing its children.
*
* Used when adding an object late in the topology.
* Will update the new object by OR'ing all its new children sets.
*
* Used when PCI backend adds a hostbridge parent, when distances
* add a new Group, etc.
*/
HWLOC_DECLSPEC int hwloc_obj_add_children_sets(hwloc_obj_t obj);
/** \brief Request a reconnection of children and levels in the topology.
*
* May be used by backends during discovery if they need arrays or lists
* of object within levels or children to be fully connected.
*
* \p flags is currently unused, must 0.
*/
HWLOC_DECLSPEC int hwloc_topology_reconnect(hwloc_topology_t topology, unsigned long flags __hwloc_attribute_unused);
/** \brief Make sure that plugins can lookup core symbols.
*
* This is a sanity check to avoid lazy-lookup failures when libhwloc
* is loaded within a plugin, and later tries to load its own plugins.
* This may fail (and abort the program) if libhwloc symbols are in a
* private namespace.
*
* \return 0 on success.
* \return -1 if the plugin cannot be successfully loaded. The caller
* plugin init() callback should return a negative error code as well.
*
* Plugins should call this function in their init() callback to avoid
* later crashes if lazy symbol resolution is used by the upper layer that
* loaded hwloc (e.g. OpenCL implementations using dlopen with RTLD_LAZY).
*
* \note The build system must define HWLOC_INSIDE_PLUGIN if and only if
* building the caller as a plugin.
*
* \note This function should remain inline so plugins can call it even
* when they cannot find libhwloc symbols.
*/
static __hwloc_inline int
hwloc_plugin_check_namespace(const char *pluginname __hwloc_attribute_unused, const char *symbol __hwloc_attribute_unused)
{
#ifdef HWLOC_INSIDE_PLUGIN
void *sym;
#ifdef HWLOC_HAVE_LTDL
lt_dlhandle handle = lt_dlopen(NULL);
#else
void *handle = dlopen(NULL, RTLD_NOW|RTLD_LOCAL);
#endif
if (!handle)
/* cannot check, assume things will work */
return 0;
#ifdef HWLOC_HAVE_LTDL
sym = lt_dlsym(handle, symbol);
lt_dlclose(handle);
#else
sym = dlsym(handle, symbol);
dlclose(handle);
#endif
if (!sym) {
static int verboseenv_checked = 0;
static int verboseenv_value = 0;
if (!verboseenv_checked) {
const char *verboseenv = getenv("HWLOC_PLUGINS_VERBOSE");
verboseenv_value = verboseenv ? atoi(verboseenv) : 0;
verboseenv_checked = 1;
}
if (verboseenv_value)
fprintf(stderr, "Plugin `%s' disabling itself because it cannot find the `%s' core symbol.\n",
pluginname, symbol);
return -1;
}
#endif /* HWLOC_INSIDE_PLUGIN */
return 0;
}
/** @} */
/** \defgroup hwlocality_components_filtering Components and Plugins: Filtering objects
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Check whether the given PCI device classid is important.
*
* \return 1 if important, 0 otherwise.
*/
static __hwloc_inline int
hwloc_filter_check_pcidev_subtype_important(unsigned classid)
{
unsigned baseclass = classid >> 8;
return (baseclass == 0x03 /* PCI_BASE_CLASS_DISPLAY */
|| baseclass == 0x02 /* PCI_BASE_CLASS_NETWORK */
|| baseclass == 0x01 /* PCI_BASE_CLASS_STORAGE */
|| baseclass == 0x00 /* Unclassified, for Atos/Bull BXI */
|| baseclass == 0x0b /* PCI_BASE_CLASS_PROCESSOR */
|| classid == 0x0c04 /* PCI_CLASS_SERIAL_FIBER */
|| classid == 0x0c06 /* PCI_CLASS_SERIAL_INFINIBAND */
|| classid == 0x0502 /* PCI_CLASS_MEMORY_CXL */
|| baseclass == 0x06 /* PCI_BASE_CLASS_BRIDGE with non-PCI downstream. the core will drop the useless ones later */
|| baseclass == 0x12 /* Processing Accelerators */);
}
/** \brief Check whether the given OS device subtype is important.
*
* \return 1 if important, 0 otherwise.
*/
static __hwloc_inline int
hwloc_filter_check_osdev_subtype_important(hwloc_obj_osdev_type_t subtype)
{
return (subtype != HWLOC_OBJ_OSDEV_DMA);
}
/** \brief Check whether a non-I/O object type should be filtered-out.
*
* Cannot be used for I/O objects.
*
* \return 1 if the object type should be kept, 0 otherwise.
*/
static __hwloc_inline int
hwloc_filter_check_keep_object_type(hwloc_topology_t topology, hwloc_obj_type_t type)
{
enum hwloc_type_filter_e filter = HWLOC_TYPE_FILTER_KEEP_NONE;
hwloc_topology_get_type_filter(topology, type, &filter);
assert(filter != HWLOC_TYPE_FILTER_KEEP_IMPORTANT); /* IMPORTANT only used for I/O */
return filter == HWLOC_TYPE_FILTER_KEEP_NONE ? 0 : 1;
}
/** \brief Check whether the given object should be filtered-out.
*
* \return 1 if the object type should be kept, 0 otherwise.
*/
static __hwloc_inline int
hwloc_filter_check_keep_object(hwloc_topology_t topology, hwloc_obj_t obj)
{
hwloc_obj_type_t type = obj->type;
enum hwloc_type_filter_e filter = HWLOC_TYPE_FILTER_KEEP_NONE;
hwloc_topology_get_type_filter(topology, type, &filter);
if (filter == HWLOC_TYPE_FILTER_KEEP_NONE)
return 0;
if (filter == HWLOC_TYPE_FILTER_KEEP_IMPORTANT) {
if (type == HWLOC_OBJ_PCI_DEVICE)
return hwloc_filter_check_pcidev_subtype_important(obj->attr->pcidev.class_id);
if (type == HWLOC_OBJ_OS_DEVICE)
return hwloc_filter_check_osdev_subtype_important(obj->attr->osdev.type);
}
return 1;
}
/** @} */
/** \defgroup hwlocality_components_pcidisc Components and Plugins: helpers for PCI discovery
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Return the offset of the given capability in the PCI config space buffer
*
* This function requires a 256-bytes config space. Unknown/unavailable bytes should be set to 0xff.
*/
HWLOC_DECLSPEC unsigned hwloc_pcidisc_find_cap(const unsigned char *config, unsigned cap);
/** \brief Fill linkspeed by reading the PCI config space where PCI_CAP_ID_EXP is at position offset.
*
* Needs 20 bytes of EXP capability block starting at offset in the config space
* for registers up to link status.
*/
HWLOC_DECLSPEC int hwloc_pcidisc_find_linkspeed(const unsigned char *config, unsigned offset, float *linkspeed);
/** \brief Return the hwloc object type (PCI device or Bridge) for the given class and configuration space.
*
* This function requires 16 bytes of common configuration header at the beginning of config.
*/
HWLOC_DECLSPEC hwloc_obj_type_t hwloc_pcidisc_check_bridge_type(unsigned device_class, const unsigned char *config);
/** \brief Fills the attributes of the given PCI bridge using the given PCI config space.
*
* This function requires 32 bytes of common configuration header at the beginning of config.
*
* Returns -1 and destroys /p obj if bridge fields are invalid.
*/
HWLOC_DECLSPEC int hwloc_pcidisc_find_bridge_buses(unsigned domain, unsigned bus, unsigned dev, unsigned func,
unsigned *secondary_busp, unsigned *subordinate_busp,
const unsigned char *config);
/** \brief Insert a PCI object in the given PCI tree by looking at PCI bus IDs.
*
* If \p treep points to \c NULL, the new object is inserted there.
*/
HWLOC_DECLSPEC void hwloc_pcidisc_tree_insert_by_busid(struct hwloc_obj **treep, struct hwloc_obj *obj);
/** \brief Add some hostbridges on top of the given tree of PCI objects and attach them to the topology.
*
* Other backends may lookup PCI objects or localities (for instance to attach OS devices)
* by using hwloc_pcidisc_find_by_busid() or hwloc_pcidisc_find_busid_parent().
*/
HWLOC_DECLSPEC int hwloc_pcidisc_tree_attach(struct hwloc_topology *topology, struct hwloc_obj *tree);
/** @} */
/** \defgroup hwlocality_components_pcifind Components and Plugins: finding PCI objects during other discoveries
*
* \note These structures and functions may change when ::HWLOC_COMPONENT_ABI is modified.
*
* @{
*/
/** \brief Find the object or a parent of a PCI bus ID.
*
* When attaching a new object (typically an OS device) whose locality
* is specified by PCI bus ID, this function returns the PCI object
* to use as a parent for attaching.
*
* If the exact PCI device with this bus ID exists, it is returned.
* Otherwise (for instance if it was filtered out), the function returns
* another object with similar locality (for instance a parent bridge,
* or the local CPU Package).
*/
HWLOC_DECLSPEC struct hwloc_obj * hwloc_pci_find_parent_by_busid(struct hwloc_topology *topology, unsigned domain, unsigned bus, unsigned dev, unsigned func);
/** \brief Find the PCI device or bridge matching a PCI bus ID exactly.
*
* This is useful for adding specific information about some objects
* based on their PCI id. When it comes to attaching objects based on
* PCI locality, hwloc_pci_find_parent_by_busid() should be preferred.
*/
HWLOC_DECLSPEC struct hwloc_obj * hwloc_pci_find_by_busid(struct hwloc_topology *topology, unsigned domain, unsigned bus, unsigned dev, unsigned func);
/** \brief Handle to a new distances structure during its addition to the topology. */
typedef void * hwloc_backend_distances_add_handle_t;
/** \brief Create a new empty distances structure.
*
* This is identical to hwloc_distances_add_create()
* but this variant is designed for backend inserting
* distances during topology discovery.
*/
HWLOC_DECLSPEC hwloc_backend_distances_add_handle_t
hwloc_backend_distances_add_create(hwloc_topology_t topology,
const char *name, unsigned long kind,
unsigned long flags);
/** \brief Specify the objects and values in a new empty distances structure.
*
* This is similar to hwloc_distances_add_values()
* but this variant is designed for backend inserting
* distances during topology discovery.
*
* The only semantical difference is that \p objs and \p values
* are not duplicated, but directly attached to the topology.
* On success, these arrays are given to the core and should not
* ever be freed by the caller anymore.
*/
HWLOC_DECLSPEC int
hwloc_backend_distances_add_values(hwloc_topology_t topology,
hwloc_backend_distances_add_handle_t handle,
unsigned nbobjs, hwloc_obj_t *objs,
hwloc_uint64_t *values,
unsigned long flags);
/** \brief Commit a new distances structure.
*
* This is similar to hwloc_distances_add_commit()
* but this variant is designed for backend inserting
* distances during topology discovery.
*/
HWLOC_DECLSPEC int
hwloc_backend_distances_add_commit(hwloc_topology_t topology,
hwloc_backend_distances_add_handle_t handle,
unsigned long flags);
/** @} */
#endif /* HWLOC_PLUGINS_H */