Hi,
Recently I find that the `shell` program has blocked.
As I run
sqcheck
Which invokes
shell -c node info
it blocks.
After some debugging, I find that there are two threads within `shell`,
Stacks of one thread looks like this:
#0 0x0000007fb7e292fc in pthread_cond_wait@@GLIBC_2.17 () from
/lib/aarch64-linux-gnu/libpthread.so.0
#1 0x000000000042ab54 in Local_IO_To_Monitor::wait_on_cv (this=0x600b40) at
clio.cxx:2240
#2 0x0000000000429888 in Local_IO_To_Monitor::send_recv (this=0x600b40,
pp_msg=0x7fb6bc95bc, pv_nw=false) at clio.cxx:1675
#3 0x000000000040aeec in attach (nid=0, name=0x5d0240 "SHELL",
program=0x4e84c8 "shell") at shell.cxx:995
#4 0x0000000000421a58 in main (argc=4, argv=0x7fffff2d58) at shell.cxx:8849
Which is wait for `iv_sr_cv`
Stacks of the other thread:
#0 local_monitor_reader (pp_arg=0x63e3) at clio.cxx:285
#1 0x0000007fb7e22fb4 in start_thread () from
/lib/aarch64-linux-gnu/libpthread.so.0
Which wait `monitor` for the signal SQ_LIO_SIGNAL_REQUEST_REPLY.
If `monitor` send the signal, then `shell` would receive it, continue, and
finish its job.
But `monitor` do not send the signal.
After some searching, I find that there is only one piece of code sending the
signal:
513 pthread_kill(iv_worker_thread_id,
SQ_LIO_SIGNAL_REQUEST_REPLY);
In function Local_IO_To_Monitor::~Local_IO_To_Monitor() of file
core/sqf/monitor/linux/clio.cxx.
As my understanding, this function should be invoked in `monitor` program, but
when I attach to that `monitor`,
whose pid is got from function `local_monitor_reader()`, and add a breakpoint
on ` Local_IO_To_Monitor::~Local_IO_To_Monitor()`,
it does not break there.
So, what should the normal procedure be? Is it incorrect for `monitor` not to
invoking Local_IO_To_Monitor::~Local_IO_To_Monitor() ?
Thank you.
Wenjun Zhu
