Remove aufs debugEBusy()

[mlaventure]

Since it was introduced no reports were made and lsof seems to cause
issues on some systems.

Signed-off-by: Kenfe-Mickael Laventure mickael.laventure@gmail.com

--

Closes: #30782

[tonistiigi]

@anusha-ragunathan Have we got any useful reports with aufs debug data since this was added? Maybe we should just remove it?

Change LGTM but even with the extra goroutine this blocks for 500ms and keeps anything else from mounting. We should only take ID based locks for the long running processes.

[anusha-ragunathan]

@tonistiigi : No reports with the added debugEbusy so far.

[mlaventure]

Should I just update the PR to remove it altogether then?

[estesp]

If not being used, seems reasonable to just PR remove it and skip the added complexity of the goroutine.

[anusha-ragunathan]

@mlaventure : SGTM

[mlaventure]

Updated PR to remove debugEBusy()

[cpuguy83]

LGTM

[thaJeztah]

Not sure it's related; failure on experimental;

23:48:02 FAIL: docker_cli_plugins_test.go:302: DockerTrustSuite.TestPluginTrustedInstall
23:48:02 
23:48:02 docker_cli_plugins_test.go:320:
23:48:02     c.Assert(err, checker.IsNil)
23:48:02 ... value *errors.errorString = &errors.errorString{s:"\nCommand: /go/src/github.com/docker/docker/bundles/17.04.0-dev/binary-client/docker plugin enable 127.0.0.1:5000/dockercli/trusted-plugin-install:latest\nExitCode: 1, Error: exit status 1\nStdout: \nStderr: Error response from daemon: error setting up propagated mount dir: invalid argument\n\n\nFailures:\nExitCode was 1 expected 0\nExpected no error\n"} ("\nCommand: /go/src/github.com/docker/docker/bundles/17.04.0-dev/binary-client/docker plugin enable 127.0.0.1:5000/dockercli/trusted-plugin-install:latest\nExitCode: 1, Error: exit status 1\nStdout: \nStderr: Error response from daemon: error setting up propagated mount dir: invalid argument\n\n\nFailures:\nExitCode was 1 expected 0\nExpected no error\n")

[anusha-ragunathan]

Failure is unrelated. That test seems to be flaky on janky/experimental. #31724

[anusha-ragunathan]

LGTM

[allencloud]

Thanks for your guys to fix this.
Actually we are facing the issue some while. In addition, I think this change could ease the pain, and this change could also be applied to old versions of docker engine.
Therefore, I suggest that we could back port this change into docker-ee 17.03. Then that action definitely brings much benefits for users.

[thaJeztah]

@allencloud this was already being considered for back porting 👍