[LU-17242] Clean up and Improve Lustre Debugging

• Type: Improvement
• Resolution: Unresolved
• Priority: Minor
• Labels: support
• Severity: 3
• Assignee: Tim Day
• Reporter: Tim Day

Description

Some parts of Lustre debugging have been superseded by newer kernel features (such as CFS_CHECK_STACK) and should be removed.

Certain subsystems stack custom macros on-top of Lustre's already custom debugging. Those should be simplified if possible.

Other subsystems use low-level debugging functions such as libcfs_debug_msg. These should use the higher level macros. That way, the underlying debugging implementation can more easily be swapped out.

Issue Links

• is related to: LU-16625 improved Lustre thread debugging
• is related to: LU-17075 replay-dual test_16 ZFS MDS crash: osd_declare_destroy() ASSERTION(dt_object_exists)
• is related to: LU-9859 libcfs simplification

Comments

[Gerrit Updater]

"Shaun Tancheff <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/59395
Subject: LU-17242 libcfs: require sched_show_task() for thread dumping
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: a43af3fe90bb8d624a208388c028abed80be0e83

[Gerrit Updater]

"Shaun Tancheff <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/59394
Subject: LU-17242 libcfs: use sched_show_task() for thread dumping
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: a0c16f938641f0a4c88ec31571c52cd45aca55c9

[Gerrit Updater]

"Timothy Day <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/58346
Subject: LU-17242 libcfs: deduplicate macros with ENUM2STR
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: de80f068969f03df28df2b3b6c61739613f0cab0

[Gerrit Updater]

"Timothy Day <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/57665
Subject: LU-17242 libcfs: implement LUSTRE_TRACE
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 332c509f7805d3a06461627622933511ecf37e11

[Gerrit Updater]

"Timothy Day <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/57356
Subject: LU-17242 libcfs: use sched_show_task() for thread dumping
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: a309b96ebfd50ed7e34404839b7164965f40876b

[Gerrit Updater]

"Oleg Drokin <[e-mail]>" merged in patch https://review.whamcloud.com/c/fs/lustre-release/+/53625/
Subject: LU-17242 debug: use dump_stack() where possible
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: ecac0c175d934fd5624c9ad8db8f45dbc33fb56c

[Gerrit Updater]

"Timothy Day <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/c/fs/lustre-release/+/53625
Subject: LU-17242 debug: use dump_stack() where possible
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: 1debf098028fec7c27310d0985934eeee4e0a67a

[Gerrit Updater]

"Oleg Drokin <[e-mail]>" merged in patch https://review.whamcloud.com/c/fs/lustre-release/+/52883/
Subject: LU-17242 debug: remove CFS_CHECK_STACK
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: edb968d04f3a3c8054c12daee1ba557f855055ce

[Tim Day]

Seems useful. I think we could register a custom panic handler. I see upstream drivers (like drivers/net/ipa/ipa_smp2p.c) doing something like that. We could avoid extending custom Lustre debugging and it should work on every panic. Adding `current->journal_info` to the handler would be easy. Getting the Lustre specific info might be tougher, but I saw some ideas upstream we could probably copy. The `ipa` just embedded the `notifier_block` in a larger struct and used `container_of` to get everything else.