Handle errors while mounting cgroup controllers

[narrieta]

If specific controller fails to mount we need to continue with the other controllers

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This change is 

[larohra]

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azurelinuxagent/common/osutil/default.py, line 349 at r1 (raw file):

                    if errors == len(controllers_to_mount):
                        raise
                    logger.warn("Could not mount cgroup controller {0}: {1}", controller, ustr(exception))

Shouldn't this line logger.warn("Could not mount cgroup controller {0}: {1}", controller, ustr(exception)) be before raising the exception because we want to see the logs incase incase both mounting failed?

[narrieta]

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azurelinuxagent/common/osutil/default.py, line 349 at r1 (raw file):

Previously, larohra wrote…

Shouldn't this line logger.warn("Could not mount cgroup controller {0}: {1}", controller, ustr(exception)) be before raising the exception because we want to see the logs incase incase both mounting failed?

The except a few lines below logs the warning/error (depending on the exception type)

[larohra]

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azurelinuxagent/common/osutil/default.py, line 349 at r1 (raw file):

ogger.error("Could not mount cgroups: {0}", ustr(e)

Ohh saw it now, thanks for clarifying

[larohra]

Reviewed 2 of 2 files at r1.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @pgombar and @vrdmr)

[vrdmr]

LGTM

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@3be3e1f). Click here to learn what that means.
The diff coverage is 90.9%.

@@            Coverage Diff             @@
##             develop    #1573   +/-   ##
==========================================
  Coverage           ?   64.29%           
==========================================
  Files              ?       78           
  Lines              ?    11080           
  Branches           ?     1566           
==========================================
  Hits               ?     7124           
  Misses             ?     3615           
  Partials           ?      341

Impacted Files	Coverage Δ
azurelinuxagent/common/osutil/default.py	57.47% <90.9%> (ø)

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[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (develop@3be3e1f). Click here to learn what that means.
The diff coverage is 90.9%.

@@            Coverage Diff             @@
##             develop    #1573   +/-   ##
==========================================
  Coverage           ?   64.29%           
==========================================
  Files              ?       78           
  Lines              ?    11080           
  Branches           ?     1566           
==========================================
  Hits               ?     7124           
  Misses             ?     3615           
  Partials           ?      341

Impacted Files	Coverage Δ
azurelinuxagent/common/osutil/default.py	57.47% <90.9%> (ø)

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Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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