Topology

include/smp/topology.h View source View on GitHub

Structs

topology_contract

struct topology_contract (2 fields) source

Contracts essentially state “I will not migrate outside of this scope”, with a set of named, verifiable reasons, so that “self topology” related functions can prove that they are in a safe state (specified), or in the edge case, have TOPOC_NONE contracts to uphold

§ enum topology_level scope

§ enum topology_caller caller

topology_cache_info

struct topology_cache_info (5 fields) source

TODO

enum this stuff

§ uint8_t level

1, 2, 3

§ uint8_t type

Data, unified, instruction

§ uint32_t size_kb

§ uint32_t line_size

§ uint32_t cores_sharing

Who shares this

topology_package_info

struct topology_package_info (2 fields) source

§ uint32_t package_id

§ struct cpu_mask cores

topology_node

struct topology_node (11 fields) source

§ enum topology_level level

§ uint64_t id

Index in this node

§ uint64_t parent

Parent node index, -1 for root

§ struct topology_node *parent_node

§ int32_t first_child

For cores this is in the cores array. For NUMA this is also in the cores array. For LLC this is in the numa array. For package this is LLC. For machine this is package.

§ int32_t nr_children

§ struct cpu_mask cpus

§ struct cpu_mask idle

§ struct cpu_mask rt_sched_rq_active

For RT scheduler

§ struct core *core

Pointer to this node’s core struct

§ union data

§ struct numa_node *numa

§ struct topology_cache_info *cache

§ struct topology_package_info *package

topology

struct topology (2 fields) source

§ struct topology_node *level[TOPOLOGY_LEVEL_MAX]

§ uint16_t count[TOPOLOGY_LEVEL_MAX]

Enums

topology_level

enum topology_level (8 variants) source

§ TOPOLOGY_LEVEL_SMT

Symmetric multiprocessing threads

§ TOPOLOGY_LEVEL_CORE

SMTs under a core

§ TOPOLOGY_LEVEL_NUMA

NUMA node

§ TOPOLOGY_LEVEL_LLC

Last level cache (some processors have multiple L3 caches for a given physical processor)

§ TOPOLOGY_LEVEL_PACKAGE

Physical processor in a socket

§ TOPOLOGY_LEVEL_MACHINE

All processors in a machine

§ TOPOLOGY_LEVEL_MAX

count

§ TOPOLOGY_LEVEL_EX_DOMAIN

This exists solely because the topology_contract has a domain granularity that does not necessarily correspond to one of the others, thus, it is outside of MAX and is its own layer just for that API

topology_caller

enum topology_caller (6 variants) source

This enum is used to verify topology contracts to guarantee a caller cannot be migrated out of a given scope of logical processors.

wrt. naming, we’ll suffix all instances of caller contracts with a C. e.g. SMPC, NODEC, PACKAGEC(specific bits go here)

TODO

we might need to come up with a naming document in docs/ because I’ve been doing this ad-hoc naming scheme stuff a few times

§ TOPC_NONE = 0

§ TOPC_IRQL = 1 << 0

§ TOPC_PINNED = 1 << 1

§ TOPC_IRQ = 1 << 2

§ TOPC_IFLAG = 1 << 3

§ TOPC_ANY = TOPC_IRQL | TOPC_PINNED | TOPC_IRQ | TOPC_IFLAG

IRQ, IRQL and IFLAG: IRQ checks in_interrupt, IRQL that >= DISPATCH

Functions

topology_mark_core_idle

void topology_mark_core_idle(cpu_id_t cpu_id, bool idle)

source

topology_find_idle_core

struct core * topology_find_idle_core(
    struct core *local_core,
    enum topology_level max_search
)

source

topology_get_smts_under_numa

struct core * * topology_get_smts_under_numa(
    struct topology_node *numa,
    size_t *count
)

source

topology_level_name

const char * topology_level_name(enum topology_level l)

source

topology_contract_verify

bool topology_contract_verify(struct topology_contract c)

source

Macros

topology_for_each_id

#define topology_for_each_id(n_, l_)

source

Expansion

#define topology_for_each_id(n_, l_) \
    for ((n_) = 0; (n_) < global.topology.count[l_]; (n_)++)