| 1 |
> Hi, |
| 2 |
> |
| 3 |
> I don't have an answer, but if you google the phrase "rcu_bh detected |
| 4 |
> stall on CPU" you can find many reports similar to yours and maybe |
| 5 |
> some information. |
| 6 |
|
| 7 |
This might be usefu |
| 8 |
lhttp://www.kernel.org/doc/Documentation/RCU/stallwarn.txt |
| 9 |
|
| 10 |
"RCU bugs can often be debugged with the help of CONFIG_RCU_TRACE" |
| 11 |
|
| 12 |
from <help> in menuconfig. |
| 13 |
|
| 14 |
│ This option provides tracing in RCU which presents stats │ |
| 15 |
│ in debugfs for debugging RCU implementation. |
| 16 |
|
| 17 |
Ok, so I've set the RCU_TRACE=y. Next question: How do I use debugfs, |
| 18 |
never used it before? |
| 19 |
|
| 20 |
> |
| 21 |
> Do you have RCU_CPU_STALL_INFO=y in your kernel config? |
| 22 |
|
| 23 |
no. |
| 24 |
|
| 25 |
syzygy@lumby ~ $ grep RCU /usr/src/linux/.config |
| 26 |
# RCU Subsystem |
| 27 |
CONFIG_TREE_RCU=y |
| 28 |
# CONFIG_PREEMPT_RCU is not set |
| 29 |
# CONFIG_RCU_TRACE is not set |
| 30 |
CONFIG_RCU_FANOUT=32 |
| 31 |
# CONFIG_RCU_FANOUT_EXACT is not set |
| 32 |
# CONFIG_RCU_FAST_NO_HZ is not set |
| 33 |
# CONFIG_TREE_RCU_TRACE is not set |
| 34 |
# CONFIG_SPARSE_RCU_POINTER is not set |
| 35 |
CONFIG_RCU_CPU_STALL_TIMEOUT=60 |
Archives