With the change to unified shims (ie: 1 shim per multiple tasks) the shimLog on Windows for the 2nd-Nth worload containers will not have an associated named pipe listener. Due to a subtle bug in errors.Wrap passing a nil error we would unblock the disconnected listener and return 0 byte successfull reads which would cause go to continually read and cap the CPU. Signed-off-by: Justin Terry (VM) <juterry@microsoft.com>
		
			
				
	
	
		
			88 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
/*
 | 
						|
   Copyright The containerd 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 v2
 | 
						|
 | 
						|
import (
 | 
						|
	"context"
 | 
						|
	"fmt"
 | 
						|
	"io"
 | 
						|
	"net"
 | 
						|
	"sync"
 | 
						|
	"time"
 | 
						|
 | 
						|
	"github.com/containerd/containerd/namespaces"
 | 
						|
	client "github.com/containerd/containerd/runtime/v2/shim"
 | 
						|
	"github.com/pkg/errors"
 | 
						|
)
 | 
						|
 | 
						|
type deferredPipeConnection struct {
 | 
						|
	ctx context.Context
 | 
						|
 | 
						|
	wg   sync.WaitGroup
 | 
						|
	once sync.Once
 | 
						|
 | 
						|
	c      net.Conn
 | 
						|
	conerr error
 | 
						|
}
 | 
						|
 | 
						|
func (dpc *deferredPipeConnection) Read(p []byte) (n int, err error) {
 | 
						|
	if dpc.c == nil {
 | 
						|
		dpc.wg.Wait()
 | 
						|
		if dpc.c == nil {
 | 
						|
			return 0, dpc.conerr
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return dpc.c.Read(p)
 | 
						|
}
 | 
						|
func (dpc *deferredPipeConnection) Close() error {
 | 
						|
	var err error
 | 
						|
	dpc.once.Do(func() {
 | 
						|
		dpc.wg.Wait()
 | 
						|
		if dpc.c != nil {
 | 
						|
			err = dpc.c.Close()
 | 
						|
		} else if dpc.conerr != nil {
 | 
						|
			err = dpc.conerr
 | 
						|
		}
 | 
						|
	})
 | 
						|
	return err
 | 
						|
}
 | 
						|
 | 
						|
// openShimLog on Windows acts as the client of the log pipe. In this way the
 | 
						|
// containerd daemon can reconnect to the shim log stream if it is restarted.
 | 
						|
func openShimLog(ctx context.Context, bundle *Bundle) (io.ReadCloser, error) {
 | 
						|
	ns, err := namespaces.NamespaceRequired(ctx)
 | 
						|
	if err != nil {
 | 
						|
		return nil, err
 | 
						|
	}
 | 
						|
	dpc := &deferredPipeConnection{
 | 
						|
		ctx: ctx,
 | 
						|
	}
 | 
						|
	dpc.wg.Add(1)
 | 
						|
	go func() {
 | 
						|
		c, conerr := client.AnonDialer(
 | 
						|
			fmt.Sprintf("\\\\.\\pipe\\containerd-shim-%s-%s-log", ns, bundle.ID),
 | 
						|
			time.Second*10,
 | 
						|
		)
 | 
						|
		if conerr != nil {
 | 
						|
			dpc.conerr = errors.Wrap(conerr, "failed to connect to shim log")
 | 
						|
		}
 | 
						|
		dpc.c = c
 | 
						|
		dpc.wg.Done()
 | 
						|
	}()
 | 
						|
	return dpc, nil
 | 
						|
}
 |