why not trace mysql function

[root@hadoop03 tools]# ./trace -U -p 26720 '/usr/local/mysql/bin/mysqld:log_buffer_flush_to_disk'
could not determine address of symbol log_buffer_flush_to_disk

[root@hadoop03 ~]# objdump -t /usr/local/mysql/bin/mysqld|grep -i log_buffer_flush_to_disk
00000000019523a5 g F .text 0000000000000057 _Z24log_buffer_flush_to_diskb

[root@hadoop03 ~]# gdb -p 26720
...
(gdb) b log_buffer_flush_to_disk
Breakpoint 1 at 0x19523b3: file /root/mysql-5.7.21/storage/innobase/log/log0log.cc, line 1417.

[root@hadoop03 tools]# uname -sr
Linux 4.15.9-1.el7.elrepo.x86_64

Is there a problem with my usage?

Start by reproducing the ./trace command against /usr/local/mysql/bin/mysqld:log_buffer_flush_to_disk and compare its symbol lookup with the objdump and gdb results shown. Read the trace tool's symbol-resolution entry point and verify whether the mangled _Z24log_buffer_flush_to_diskb symbol is handled; done means explaining the failure or confirming a usage or tool defect.

Written by the indexing model from the issue text.