#20067

Committed 12 Nov 2025 07:34PM UTC coverage: 88.522% (-0.03%) from 88.552%

Build # #20067

Build Type

push

github

Committed by

web-flow

Commit Message

core: Release lock before closing shared resource

If a resource has dependencies that also use SharedResourceHolder, and
its close() blocks waiting for processing on another thread, then the
threads could become deadlocked on the SharedResourceHolder lock. Our
answer should be "don't block," but it's also good to avoid calling
arbitrary code with a lock held.

create() is still called with the lock held, but that seems less likely
to do work on another thread, and it is harder to avoid the lock.
close() is very easy to call without the lock.

See d50098f80 and b/458736211

Run Details

35069 of 39616 relevant lines covered (88.52%)

0.89 hits per line

Source File
Press 'n' to go to next uncovered line, 'b' for previous

87.88

/../netty/src/main/java/io/grpc/netty/ClientTransportLifecycleManager.java

/*
 * Copyright 2016 The gRPC 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 io.grpc.netty;

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import io.grpc.Attributes;
import io.grpc.Status;
import io.grpc.internal.ManagedClientTransport;

/** Maintainer of transport lifecycle status. */
final class ClientTransportLifecycleManager {
  private final ManagedClientTransport.Listener listener;
  private boolean transportReady;
  private boolean transportShutdown;
  private boolean transportInUse;
  /** null iff !transportShutdown. */
  private Status shutdownStatus;
  /** null iff !transportShutdown. */
  private boolean transportTerminated;

  public ClientTransportLifecycleManager(ManagedClientTransport.Listener listener) {
    this.listener = listener;
  }

  public Attributes filterAttributes(Attributes attributes) {
    if (transportReady || transportShutdown) {
      return attributes;
    }
    return listener.filterTransport(attributes);
  }

  public void notifyReady() {
    if (transportReady || transportShutdown) {
      return;
    }
    transportReady = true;
    listener.transportReady();
  }

  /**
   * Marks transport as shutdown, but does not set the error status. This must eventually be
   * followed by a call to notifyShutdown.
   */
  public void notifyGracefulShutdown(Status s) {
    if (transportShutdown) {
      return;
    }
    transportShutdown = true;
    listener.transportShutdown(s);
  }

  /** Returns {@code true} if was the first shutdown. */
  @CanIgnoreReturnValue
  public boolean notifyShutdown(Status s) {
    notifyGracefulShutdown(s);
    if (shutdownStatus != null) {
      return false;
    }
    shutdownStatus = s;
    return true;
  }

  public void notifyInUse(boolean inUse) {
    if (inUse == transportInUse) {
      return;
    }
    transportInUse = inUse;
    listener.transportInUse(inUse);
  }

  public void notifyTerminated(Status s) {
    if (transportTerminated) {
      return;
    }
    transportTerminated = true;
    notifyShutdown(s);
    listener.transportTerminated();
  }

  public Status getShutdownStatus() {
    return shutdownStatus;
  }

}

1	/*
2	* Copyright 2016 The gRPC Authors
3	*
4	* Licensed under the Apache License, Version 2.0 (the "License");
5	* you may not use this file except in compliance with the License.
6	* You may obtain a copy of the License at
7	*
8	* http://www.apache.org/licenses/LICENSE-2.0
9	*
10	* Unless required by applicable law or agreed to in writing, software
11	* distributed under the License is distributed on an "AS IS" BASIS,
12	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13	* See the License for the specific language governing permissions and
14	* limitations under the License.
15	*/
16
17	package io.grpc.netty;
18
19	import com.google.errorprone.annotations.CanIgnoreReturnValue;
20	import io.grpc.Attributes;
21	import io.grpc.Status;
22	import io.grpc.internal.ManagedClientTransport;
23
24	/** Maintainer of transport lifecycle status. */
25	final class ClientTransportLifecycleManager {
26	private final ManagedClientTransport.Listener listener;
27	private boolean transportReady;
28	private boolean transportShutdown;
29	private boolean transportInUse;
30	/** null iff !transportShutdown. */
31	private Status shutdownStatus;
32	/** null iff !transportShutdown. */
33	private boolean transportTerminated;
34
35	public ClientTransportLifecycleManager(ManagedClientTransport.Listener listener) {	1✔
36	this.listener = listener;	1✔
37	}	1✔
38
39	public Attributes filterAttributes(Attributes attributes) {
40	if (transportReady \|\| transportShutdown) {	1✔
41	return attributes;	×
42	}
43	return listener.filterTransport(attributes);	1✔
44	}
45
46	public void notifyReady() {
47	if (transportReady \|\| transportShutdown) {	1✔
48	return;	×
49	}
50	transportReady = true;	1✔
51	listener.transportReady();	1✔
52	}	1✔
53
54	/**
55	* Marks transport as shutdown, but does not set the error status. This must eventually be
56	* followed by a call to notifyShutdown.
57	*/
58	public void notifyGracefulShutdown(Status s) {
59	if (transportShutdown) {	1✔
60	return;	1✔
61	}
62	transportShutdown = true;	1✔
63	listener.transportShutdown(s);	1✔
64	}	1✔
65
66	/** Returns {@code true} if was the first shutdown. */
67	@CanIgnoreReturnValue
68	public boolean notifyShutdown(Status s) {
69	notifyGracefulShutdown(s);	1✔
70	if (shutdownStatus != null) {	1✔
71	return false;	1✔
72	}
73	shutdownStatus = s;	1✔
74	return true;	1✔
75	}
76
77	public void notifyInUse(boolean inUse) {
78	if (inUse == transportInUse) {	1✔
79	return;	×
80	}
81	transportInUse = inUse;	1✔
82	listener.transportInUse(inUse);	1✔
83	}	1✔
84
85	public void notifyTerminated(Status s) {
86	if (transportTerminated) {	1✔
87	return;	×
88	}
89	transportTerminated = true;	1✔
90	notifyShutdown(s);	1✔
91	listener.transportTerminated();	1✔
92	}	1✔
93
94	public Status getShutdownStatus() {
95	return shutdownStatus;	1✔
96	}
97
98	}

grpc / grpc-java / #20067

Source File Press 'n' to go to next uncovered line, 'b' for previous

Source File
Press 'n' to go to next uncovered line, 'b' for previous