What were you trying to do that didn't work?

When cu is running program, it happened that the multiple threads are caught in the pthread_rwlock_rdlock of the same lock object:

–
#0 0x00002b76c4b8954d in __lll_lock_wait () from traffic_server-libs/lib64/libpthread.so.0
#1 0x00002b76c4b861b2 in pthread_rwlock_rdlock () from traffic_server-libs/lib64/libpthread.so.0
–
It seems to be a bug in glibc/libpthread

Please provide the package NVR for which bug is seen:

How reproducible:

everytime

Steps to reproduce

We found a deadlock scenario in NPTL's rwlock implementation,
relating to additional scheduling dependencies which NPTL imposes on
concurrent readers.

It happens when facing sufficient congestion between both
read- and write-locking candidates queued.

Expected results

Deadlock should not occur

Actual results

Deadlock occurring causing system to get hung and need to be restarted