[LU-13253] sanity/177 leaves threads blocked in libcfs_debug_dumplog()

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.14.0
• Severity: 3
• Assignee: Alex Zhuravlev
• Reporter: Alex Zhuravlev

Description

the problem was introduced by:

acb6ee1f1f 2020-02-01 | LU-8304 libcfs: convert debug_ctlwq to a completion

the root cause is that libcfs_debug_dumplog() can be called by few threads simultaneously and each thread re-initialize the global state debug_complete unconditionally.
I reverted the patch locally to pass sanity.sh, but I guess we can wrap libcfs_debug_dumplog() with a mutex to serialize calls.

Issue Links

• is related to: LU-8304 libcfs_debug_dumplog calls potentially sleeping function in wrong state