| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * sched-domains (multiprocessor balancing) flag declarations. |
| */ |
| |
| #ifndef SD_FLAG |
| # error "Incorrect import of SD flags definitions" |
| #endif |
| |
| /* |
| * Hierarchical metaflags |
| * |
| * SHARED_CHILD: These flags are meant to be set from the base domain upwards. |
| * If a domain has this flag set, all of its children should have it set. This |
| * is usually because the flag describes some shared resource (all CPUs in that |
| * domain share the same resource), or because they are tied to a scheduling |
| * behaviour that we want to disable at some point in the hierarchy for |
| * scalability reasons. |
| * |
| * In those cases it doesn't make sense to have the flag set for a domain but |
| * not have it in (some of) its children: sched domains ALWAYS span their child |
| * domains, so operations done with parent domains will cover CPUs in the lower |
| * child domains. |
| * |
| * |
| * SHARED_PARENT: These flags are meant to be set from the highest domain |
| * downwards. If a domain has this flag set, all of its parents should have it |
| * set. This is usually for topology properties that start to appear above a |
| * certain level (e.g. domain starts spanning CPUs outside of the base CPU's |
| * socket). |
| */ |
| #define SDF_SHARED_CHILD 0x1 |
| #define SDF_SHARED_PARENT 0x2 |
| |
| /* |
| * Behavioural metaflags |
| * |
| * NEEDS_GROUPS: These flags are only relevant if the domain they are set on has |
| * more than one group. This is usually for balancing flags (load balancing |
| * involves equalizing a metric between groups), or for flags describing some |
| * shared resource (which would be shared between groups). |
| */ |
| #define SDF_NEEDS_GROUPS 0x4 |
| |
| /* |
| * Balance when about to become idle |
| * |
| * SHARED_CHILD: Set from the base domain up to cpuset.sched_relax_domain_level. |
| * NEEDS_GROUPS: Load balancing flag. |
| */ |
| SD_FLAG(SD_BALANCE_NEWIDLE, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Balance on exec |
| * |
| * SHARED_CHILD: Set from the base domain up to the NUMA reclaim level. |
| * NEEDS_GROUPS: Load balancing flag. |
| */ |
| SD_FLAG(SD_BALANCE_EXEC, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Balance on fork, clone |
| * |
| * SHARED_CHILD: Set from the base domain up to the NUMA reclaim level. |
| * NEEDS_GROUPS: Load balancing flag. |
| */ |
| SD_FLAG(SD_BALANCE_FORK, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Balance on wakeup |
| * |
| * SHARED_CHILD: Set from the base domain up to cpuset.sched_relax_domain_level. |
| * NEEDS_GROUPS: Load balancing flag. |
| */ |
| SD_FLAG(SD_BALANCE_WAKE, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Consider waking task on waking CPU. |
| * |
| * SHARED_CHILD: Set from the base domain up to the NUMA reclaim level. |
| */ |
| SD_FLAG(SD_WAKE_AFFINE, SDF_SHARED_CHILD) |
| |
| /* |
| * Domain members have different CPU capacities |
| * |
| * SHARED_PARENT: Set from the topmost domain down to the first domain where |
| * asymmetry is detected. |
| * NEEDS_GROUPS: Per-CPU capacity is asymmetric between groups. |
| */ |
| SD_FLAG(SD_ASYM_CPUCAPACITY, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Domain members have different CPU capacities spanning all unique CPU |
| * capacity values. |
| * |
| * SHARED_PARENT: Set from the topmost domain down to the first domain where |
| * all available CPU capacities are visible |
| * NEEDS_GROUPS: Per-CPU capacity is asymmetric between groups. |
| */ |
| SD_FLAG(SD_ASYM_CPUCAPACITY_FULL, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Domain members share CPU capacity (i.e. SMT) |
| * |
| * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share |
| * CPU capacity. |
| * NEEDS_GROUPS: Capacity is shared between groups. |
| */ |
| SD_FLAG(SD_SHARE_CPUCAPACITY, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Domain members share CPU package resources (i.e. caches) |
| * |
| * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share |
| * the same cache(s). |
| * NEEDS_GROUPS: Caches are shared between groups. |
| */ |
| SD_FLAG(SD_SHARE_PKG_RESOURCES, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Only a single load balancing instance |
| * |
| * SHARED_PARENT: Set for all NUMA levels above NODE. Could be set from a |
| * different level upwards, but it doesn't change that if a |
| * domain has this flag set, then all of its parents need to have |
| * it too (otherwise the serialization doesn't make sense). |
| * NEEDS_GROUPS: No point in preserving domain if it has a single group. |
| */ |
| SD_FLAG(SD_SERIALIZE, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Place busy tasks earlier in the domain |
| * |
| * SHARED_CHILD: Usually set on the SMT level. Technically could be set further |
| * up, but currently assumed to be set from the base domain |
| * upwards (see update_top_cache_domain()). |
| * NEEDS_GROUPS: Load balancing flag. |
| */ |
| SD_FLAG(SD_ASYM_PACKING, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Prefer to place tasks in a sibling domain |
| * |
| * Set up until domains start spanning NUMA nodes. Close to being a SHARED_CHILD |
| * flag, but cleared below domains with SD_ASYM_CPUCAPACITY. |
| * |
| * NEEDS_GROUPS: Load balancing flag. |
| */ |
| SD_FLAG(SD_PREFER_SIBLING, SDF_NEEDS_GROUPS) |
| |
| /* |
| * sched_groups of this level overlap |
| * |
| * SHARED_PARENT: Set for all NUMA levels above NODE. |
| * NEEDS_GROUPS: Overlaps can only exist with more than one group. |
| */ |
| SD_FLAG(SD_OVERLAP, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) |
| |
| /* |
| * Cross-node balancing |
| * |
| * SHARED_PARENT: Set for all NUMA levels above NODE. |
| * NEEDS_GROUPS: No point in preserving domain if it has a single group. |
| */ |
| SD_FLAG(SD_NUMA, SDF_SHARED_PARENT | SDF_NEEDS_GROUPS) |