[root@sv-asterisk ~]# asterisk -rx "core show locks"

=======================================================================
=== Currently Held Locks ==============================================
=======================================================================
===
=== <pending> <lock#> (<file>): <lock type> <line num> <function> <lock name> <lock addr> (times locked)
===
=== Thread ID: 1090357568 (tps_processing_function started at [  451] taskprocessor.c ast_taskprocessor_get())
=== ---> Lock #0 (pbx.c): MUTEX 9352 ast_rdlock_contexts &conlock 0x822dc0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/sbin/asterisk [0x4f830e]
        /usr/sbin/asterisk(ast_rdlock_contexts+0x23) [0x508ea9]
        /usr/sbin/asterisk [0x4f5596]
        /usr/sbin/asterisk [0x548be1]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== ---> Lock #1 (pbx.c): RDLOCK 3865 handle_statechange &(&hints)->lock 0x8251b0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/sbin/asterisk [0x4eb9b4]
        /usr/sbin/asterisk [0x4f55b5]
        /usr/sbin/asterisk [0x548be1]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== ---> Waiting for Lock #2 (chan_sip.c): MUTEX 12922 cb_extensionstate p 0x2aaaacaf7ce0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/sbin/asterisk [0x441549]
        /usr/sbin/asterisk(_ao2_lock+0x53) [0x441897]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac0590dc2]
        /usr/sbin/asterisk [0x4f56e0]
        /usr/sbin/asterisk [0x548be1]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== --- ---> Locked Here: chan_sip.c line 7498 (find_call)
=== -------------------------------------------------------------------
===
=== Thread ID: 1098897728 (do_monitor           started at [22721] chan_sip.c restart_monitor())
=== ---> Lock #0 (chan_sip.c): MUTEX 22171 handle_request_do &netlock 0x2aaac07f40c0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac055ed4c]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c08a9]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c066a]
        /usr/sbin/asterisk(ast_io_wait+0x1ba) [0x4cc7f4]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c22cf]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== ---> Lock #1 (chan_sip.c): MUTEX 7498 find_call p 0x2aaaacaf7ce0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/sbin/asterisk [0x4420b0]
        /usr/sbin/asterisk(_ao2_trylock+0x53) [0x4422da]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac057569d]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c08bd]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c066a]
        /usr/sbin/asterisk(ast_io_wait+0x1ba) [0x4cc7f4]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c22cf]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== ---> Waiting for Lock #2 (pbx.c): MUTEX 9352 ast_rdlock_contexts &conlock 0x822dc0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/sbin/asterisk [0x4f830e]
        /usr/sbin/asterisk(ast_rdlock_contexts+0x23) [0x508ea9]
        /usr/sbin/asterisk [0x4f52ab]
        /usr/sbin/asterisk(ast_get_hint+0x30) [0x4f632e]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac059508b]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05bd9c2]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05bfd86]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c0dd4]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c066a]
        /usr/sbin/asterisk(ast_io_wait+0x1ba) [0x4cc7f4]
        /usr/lib/asterisk/modules/chan_sip.so [0x2aaac05c22cf]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== --- ---> Locked Here: pbx.c line 9352 (ast_rdlock_contexts)
=== -------------------------------------------------------------------
===
=== Thread ID: 1086720320 (pri_dchannel         started at [13752] chan_dahdi.c start_pri())
=== ---> Lock #0 (chan_dahdi.c): MUTEX 12687 pri_dchannel &pri->lock 0x2aaabc3d7008 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/lib/asterisk/modules/chan_dahdi.so [0x2aaabc1834a6]
        /usr/lib/asterisk/modules/chan_dahdi.so [0x2aaabc1ae27b]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== ---> Lock #1 (chan_dahdi.c): MUTEX 12933 pri_dchannel &pri->pvts[chanpos]->lock 0x2aaad58e5ec0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/lib/asterisk/modules/chan_dahdi.so [0x2aaabc1834a6]
        /usr/lib/asterisk/modules/chan_dahdi.so [0x2aaabc1afa71]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== ---> Waiting for Lock #2 (pbx.c): MUTEX 9352 ast_rdlock_contexts &conlock 0x822dc0 (1)
        /usr/sbin/asterisk(ast_bt_get_addresses+0x1a) [0x4d7caf]
        /usr/sbin/asterisk [0x4f830e]
        /usr/sbin/asterisk(ast_rdlock_contexts+0x23) [0x508ea9]
        /usr/sbin/asterisk [0x4f48db]
        /usr/sbin/asterisk(ast_canmatch_extension+0x61) [0x4f6531]
        /usr/lib/asterisk/modules/chan_dahdi.so [0x2aaabc1b0319]
        /usr/sbin/asterisk [0x55b6b1]
        /lib64/libpthread.so.0 [0x34f920673d]
        /lib64/libc.so.6(clone+0x6d) [0x34f86d3d1d]
=== --- ---> Locked Here: pbx.c line 9352 (ast_rdlock_contexts)
=== -------------------------------------------------------------------
===
=======================================================================