eth/downloader: wait for all fetcher goroutines to exit before terminating (#16509)

This commit is contained in:
gary rong 2018-04-16 16:37:48 +08:00 committed by Péter Szilágyi
parent 6b2b328cdb
commit de2a7bb764

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@ -135,9 +135,10 @@ type Downloader struct {
stateCh chan dataPack // [eth/63] Channel receiving inbound node state data
// Cancellation and termination
cancelPeer string // Identifier of the peer currently being used as the master (cancel on drop)
cancelCh chan struct{} // Channel to cancel mid-flight syncs
cancelLock sync.RWMutex // Lock to protect the cancel channel and peer in delivers
cancelPeer string // Identifier of the peer currently being used as the master (cancel on drop)
cancelCh chan struct{} // Channel to cancel mid-flight syncs
cancelLock sync.RWMutex // Lock to protect the cancel channel and peer in delivers
cancelWg sync.WaitGroup // Make sure all fetcher goroutines have exited.
quitCh chan struct{} // Quit channel to signal termination
quitLock sync.RWMutex // Lock to prevent double closes
@ -476,12 +477,11 @@ func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td *big.I
// spawnSync runs d.process and all given fetcher functions to completion in
// separate goroutines, returning the first error that appears.
func (d *Downloader) spawnSync(fetchers []func() error) error {
var wg sync.WaitGroup
errc := make(chan error, len(fetchers))
wg.Add(len(fetchers))
d.cancelWg.Add(len(fetchers))
for _, fn := range fetchers {
fn := fn
go func() { defer wg.Done(); errc <- fn() }()
go func() { defer d.cancelWg.Done(); errc <- fn() }()
}
// Wait for the first error, then terminate the others.
var err error
@ -498,12 +498,10 @@ func (d *Downloader) spawnSync(fetchers []func() error) error {
}
d.queue.Close()
d.Cancel()
wg.Wait()
return err
}
// Cancel cancels all of the operations and resets the queue. It returns true
// if the cancel operation was completed.
// Cancel cancels all of the operations and resets the queue.
func (d *Downloader) Cancel() {
// Close the current cancel channel
d.cancelLock.Lock()
@ -516,6 +514,7 @@ func (d *Downloader) Cancel() {
}
}
d.cancelLock.Unlock()
d.cancelWg.Wait()
}
// Terminate interrupts the downloader, canceling all pending operations.