mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-12-23 21:40:20 +00:00
76 lines
2.3 KiB
Go
76 lines
2.3 KiB
Go
|
// Copyright 2019 The etcd Authors
|
||
|
|
//
|
||
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
// you may not use this file except in compliance with the License.
|
||
|
|
// You may obtain a copy of the License at
|
||
|
|
//
|
||
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
//
|
||
|
|
// Unless required by applicable law or agreed to in writing, software
|
||
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
// See the License for the specific language governing permissions and
|
||
|
|
// limitations under the License.
|
||
|
|
|
||
|
|
package quorum
|
||
|
|
|
||
|
|
// JointConfig is a configuration of two groups of (possibly overlapping)
|
||
|
|
// majority configurations. Decisions require the support of both majorities.
|
||
|
|
type JointConfig [2]MajorityConfig
|
||
|
|
|
||
|
|
func (c JointConfig) String() string {
|
||
|
|
if len(c[1]) > 0 {
|
||
|
|
return c[0].String() + "&&" + c[1].String()
|
||
|
|
}
|
||
|
|
return c[0].String()
|
||
|
|
}
|
||
|
|
|
||
|
|
// IDs returns a newly initialized map representing the set of voters present
|
||
|
|
// in the joint configuration.
|
||
|
|
func (c JointConfig) IDs() map[uint64]struct{} {
|
||
|
|
m := map[uint64]struct{}{}
|
||
|
|
for _, cc := range c {
|
||
|
|
for id := range cc {
|
||
|
|
m[id] = struct{}{}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return m
|
||
|
|
}
|
||
|
|
|
||
|
|
// Describe returns a (multi-line) representation of the commit indexes for the
|
||
|
|
// given lookuper.
|
||
|
|
func (c JointConfig) Describe(l AckedIndexer) string {
|
||
|
|
return MajorityConfig(c.IDs()).Describe(l)
|
||
|
|
}
|
||
|
|
|
||
|
|
// CommittedIndex returns the largest committed index for the given joint
|
||
|
|
// quorum. An index is jointly committed if it is committed in both constituent
|
||
|
|
// majorities.
|
||
|
|
func (c JointConfig) CommittedIndex(l AckedIndexer) Index {
|
||
|
|
idx0 := c[0].CommittedIndex(l)
|
||
|
|
idx1 := c[1].CommittedIndex(l)
|
||
|
|
if idx0 < idx1 {
|
||
|
|
return idx0
|
||
|
|
}
|
||
|
|
return idx1
|
||
|
|
}
|
||
|
|
|
||
|
|
// VoteResult takes a mapping of voters to yes/no (true/false) votes and returns
|
||
|
|
// a result indicating whether the vote is pending, lost, or won. A joint quorum
|
||
|
|
// requires both majority quorums to vote in favor.
|
||
|
|
func (c JointConfig) VoteResult(votes map[uint64]bool) VoteResult {
|
||
|
|
r1 := c[0].VoteResult(votes)
|
||
|
|
r2 := c[1].VoteResult(votes)
|
||
|
|
|
||
|
|
if r1 == r2 {
|
||
|
|
// If they agree, return the agreed state.
|
||
|
|
return r1
|
||
|
|
}
|
||
|
|
if r1 == VoteLost || r2 == VoteLost {
|
||
|
|
// If either config has lost, loss is the only possible outcome.
|
||
|
|
return VoteLost
|
||
|
|
}
|
||
|
|
// One side won, the other one is pending, so the whole outcome is.
|
||
|
|
return VotePending
|
||
|
|
}
|