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/* 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)
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