[LU-7400] top_trans_create() followed by top_trans_stop() get stuck

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.8.0
• Affects Version/s: Lustre 2.8.0
• Severity: 3
• Assignee: Alex Zhuravlev
• Reporter: Alex Zhuravlev

Description

as sub_thandle_register_stop_cb() is called in top_trans_start(), then missing top_trans_start() (which is valid case) cause top_trans_stop() to wait indefinitely for a missing stop callbacks.

Comments

[Joseph Gmitter (Inactive)]

Landed for 2.8

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/17059/
Subject: LU-7400 lod: register stop callbacks at create
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 082eabdeaa0c2a0f536accf7028e5ab5061c2c46

[Di Wang]

Since we saw this in soak-test DNE, and we have to pass it before release, so let's make it blocker for now.

[Di Wang]

I think we also have this issue for commit callback, which I found in failover soak-test. I will update the patch to resolve them together. IMHO, this should get into 2.8, since it will cause endless recovery.

[Alex Zhuravlev]

for example, if a target fails during recovery and some of preparation RPC (e.g. fetching EA) returns an error, then the original migration process got stuck. even if the failed target is back, it's still stuck. I think it makes sense to consider landing.

[Andreas Dilger]

Alex, under what kind of workload is this bug hit, and how easily does that happen? Is this a patch that needs to be landed for 2.8.0?

[Gerrit Updater]

Alex Zhuravlev ([e-mail]) uploaded a new patch: http://review.whamcloud.com/17059
Subject: LU-7400 lod: register commit callbacks at create
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 58a978451fd7504ecc9ab3bbf841a3499401f0b2