k8s.io/kubernetes@v1.29.3/pkg/kubelet/cm/topologymanager/policy_single_numa_node.go (about)

     1  /*
     2  Copyright 2019 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package topologymanager
    18  
    19  type singleNumaNodePolicy struct {
    20  	// numaInfo represents list of NUMA Nodes available on the underlying machine and distances between them
    21  	numaInfo *NUMAInfo
    22  	opts     PolicyOptions
    23  }
    24  
    25  var _ Policy = &singleNumaNodePolicy{}
    26  
    27  // PolicySingleNumaNode policy name.
    28  const PolicySingleNumaNode string = "single-numa-node"
    29  
    30  // NewSingleNumaNodePolicy returns single-numa-node policy.
    31  func NewSingleNumaNodePolicy(numaInfo *NUMAInfo, opts PolicyOptions) Policy {
    32  	return &singleNumaNodePolicy{numaInfo: numaInfo, opts: opts}
    33  }
    34  
    35  func (p *singleNumaNodePolicy) Name() string {
    36  	return PolicySingleNumaNode
    37  }
    38  
    39  func (p *singleNumaNodePolicy) canAdmitPodResult(hint *TopologyHint) bool {
    40  	return hint.Preferred
    41  }
    42  
    43  // Return hints that have valid bitmasks with exactly one bit set.
    44  func filterSingleNumaHints(allResourcesHints [][]TopologyHint) [][]TopologyHint {
    45  	var filteredResourcesHints [][]TopologyHint
    46  	for _, oneResourceHints := range allResourcesHints {
    47  		var filtered []TopologyHint
    48  		for _, hint := range oneResourceHints {
    49  			if hint.NUMANodeAffinity == nil && hint.Preferred {
    50  				filtered = append(filtered, hint)
    51  			}
    52  			if hint.NUMANodeAffinity != nil && hint.NUMANodeAffinity.Count() == 1 && hint.Preferred {
    53  				filtered = append(filtered, hint)
    54  			}
    55  		}
    56  		filteredResourcesHints = append(filteredResourcesHints, filtered)
    57  	}
    58  	return filteredResourcesHints
    59  }
    60  
    61  func (p *singleNumaNodePolicy) Merge(providersHints []map[string][]TopologyHint) (TopologyHint, bool) {
    62  	filteredHints := filterProvidersHints(providersHints)
    63  	// Filter to only include don't cares and hints with a single NUMA node.
    64  	singleNumaHints := filterSingleNumaHints(filteredHints)
    65  
    66  	merger := NewHintMerger(p.numaInfo, singleNumaHints, p.Name(), p.opts)
    67  	bestHint := merger.Merge()
    68  
    69  	if bestHint.NUMANodeAffinity.IsEqual(p.numaInfo.DefaultAffinityMask()) {
    70  		bestHint = TopologyHint{nil, bestHint.Preferred}
    71  	}
    72  
    73  	admit := p.canAdmitPodResult(&bestHint)
    74  	return bestHint, admit
    75  }