mirror of https://github.com/minio/minio.git
87 lines
2.2 KiB
Go
87 lines
2.2 KiB
Go
|
// Copyright (c) 2015-2022 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 cmd
|
||
|
|
||
|
import (
|
||
|
"context"
|
||
|
"time"
|
||
|
)
|
||
|
|
||
|
var sharedLockTimeout = newDynamicTimeoutWithOpts(dynamicTimeoutOpts{
|
||
|
timeout: 30 * time.Second,
|
||
|
minimum: 10 * time.Second,
|
||
|
retryInterval: time.Minute,
|
||
|
})
|
||
|
|
||
|
type sharedLock struct {
|
||
|
lockContext chan LockContext
|
||
|
}
|
||
|
|
||
|
func (ld sharedLock) backgroundRoutine(ctx context.Context, objAPI ObjectLayer, lockName string) {
|
||
|
for {
|
||
|
locker := objAPI.NewNSLock(minioMetaBucket, lockName)
|
||
|
lkctx, err := locker.GetLock(ctx, sharedLockTimeout)
|
||
|
if err != nil {
|
||
|
continue
|
||
|
}
|
||
|
|
||
|
for {
|
||
|
select {
|
||
|
case <-ctx.Done():
|
||
|
return
|
||
|
case <-lkctx.Context().Done():
|
||
|
// The context of the lock is canceled, this can happen
|
||
|
// if one lock lost quorum due to cluster instability
|
||
|
// in that case, try to lock again.
|
||
|
break
|
||
|
case ld.lockContext <- lkctx:
|
||
|
// Send the lock context to anyone asking for it
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
func mergeContext(ctx1, ctx2 context.Context) (context.Context, context.CancelFunc) {
|
||
|
ctx, cancel := context.WithCancel(context.Background())
|
||
|
go func() {
|
||
|
select {
|
||
|
case <-ctx1.Done():
|
||
|
case <-ctx2.Done():
|
||
|
}
|
||
|
|
||
|
cancel()
|
||
|
}()
|
||
|
return ctx, cancel
|
||
|
}
|
||
|
|
||
|
func (ld sharedLock) GetLock(ctx context.Context) (context.Context, context.CancelFunc) {
|
||
|
select {
|
||
|
case l := <-ld.lockContext:
|
||
|
return mergeContext(l.Context(), ctx)
|
||
|
}
|
||
|
}
|
||
|
|
||
|
func newSharedLock(ctx context.Context, objAPI ObjectLayer, lockName string) *sharedLock {
|
||
|
l := &sharedLock{
|
||
|
lockContext: make(chan LockContext),
|
||
|
}
|
||
|
go l.backgroundRoutine(ctx, objAPI, lockName)
|
||
|
|
||
|
return l
|
||
|
}
|