Re: [PATCH v11 5/9] Reimplement RLIMIT_MSGQUEUE on top of ucounts

[Ma, XinjianX]

Hi Alexey,

When lkp team run kernel selftests, we found after these series of patches, testcase mqueue: mq_perf_tests
in kselftest failed with following message. 

If you confirm and fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot lkp@xxxxxxxxx

```
# selftests: mqueue: mq_perf_tests
#
# Initial system state:
#       Using queue path:                       /mq_perf_tests
#       RLIMIT_MSGQUEUE(soft):                  819200
#       RLIMIT_MSGQUEUE(hard):                  819200
#       Maximum Message Size:                   8192
#       Maximum Queue Size:                     10
#       Nice value:                             0
#
# Adjusted system state for testing:
#       RLIMIT_MSGQUEUE(soft):                  (unlimited)
#       RLIMIT_MSGQUEUE(hard):                  (unlimited)
#       Maximum Message Size:                   16777216
#       Maximum Queue Size:                     65530
#       Nice value:                             -20
#       Continuous mode:                        (disabled)
#       CPUs to pin:                            3
# ./mq_perf_tests: mq_open() at 296: Too many open files
not ok 2 selftests: mqueue: mq_perf_tests # exit=1
```    

Test env:
rootfs: debian-10
gcc version: 9

------
Thanks 
Ma Xinjian