mirror of https://github.com/minio/minio.git
64 lines
1.6 KiB
Go
64 lines
1.6 KiB
Go
|
// Copyright (c) 2022 MinIO, Inc.
|
||
|
|
//
|
||
|
|
// This file is part of MinIO Object Storage stack
|
||
|
|
//
|
||
|
|
// This program is free software: you can redistribute it and/or modify
|
||
|
|
// it under the terms of the GNU Affero General Public License as published by
|
||
|
|
// the Free Software Foundation, either version 3 of the License, or
|
||
|
|
// (at your option) any later version.
|
||
|
|
//
|
||
|
|
// This program is distributed in the hope that it will be useful
|
||
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
// GNU Affero General Public License for more details.
|
||
|
|
//
|
||
|
|
// You should have received a copy of the GNU Affero General Public License
|
||
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
|
||
|
|
package jobtokens
|
||
|
|
|
||
|
|
import (
|
||
|
|
"errors"
|
||
|
|
"sync"
|
||
|
|
)
|
||
|
|
|
||
|
|
// JobTokens provides a bounded semaphore with the ability to wait until all
|
||
|
|
// concurrent jobs finish.
|
||
|
|
type JobTokens struct {
|
||
|
|
wg sync.WaitGroup
|
||
|
|
tokens chan struct{}
|
||
|
|
}
|
||
|
|
|
||
|
|
// New creates a JobTokens object which allows up to n jobs to proceed
|
||
|
|
// concurrently. n must be > 0.
|
||
|
|
func New(n int) (*JobTokens, error) {
|
||
|
|
if n <= 0 {
|
||
|
|
return nil, errors.New("n must be > 0")
|
||
|
|
}
|
||
|
|
|
||
|
|
tokens := make(chan struct{}, n)
|
||
|
|
for i := 0; i < n; i++ {
|
||
|
|
tokens <- struct{}{}
|
||
|
|
}
|
||
|
|
return &JobTokens{
|
||
|
|
tokens: tokens,
|
||
|
|
}, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// Take is how a job (goroutine) can Take its turn.
|
||
|
|
func (jt *JobTokens) Take() {
|
||
|
|
jt.wg.Add(1)
|
||
|
|
<-jt.tokens
|
||
|
|
}
|
||
|
|
|
||
|
|
// Give is how a job (goroutine) can give back its turn once done.
|
||
|
|
func (jt *JobTokens) Give() {
|
||
|
|
jt.wg.Done()
|
||
|
|
jt.tokens <- struct{}{}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Wait waits for all ongoing concurrent jobs to complete
|
||
|
|
func (jt *JobTokens) Wait() {
|
||
|
|
jt.wg.Wait()
|
||
|
|
}
|