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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US>I got a thread deadlock during audio routing. Could anyone share some advice to debug a deadlocked thread? Great thanks!<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>My scenario is:<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo2'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>make a VOIP call with a Bluetooth headset, <o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo2'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>disconnect the Bluetooth headset during the phone call<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo2'><![if !supportLists]><span lang=EN-US><span style='mso-list:Ignore'>3.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US>then the phone input & output stream shall be routed back to ALSA sink & source and module-echo-cancel’s filter sink& source shall be automatically inserted.<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:0cm'><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>But I got a deadlock on step 3. It seems the AEC virtual sink does not process " PA_SINK_MESSAGE_SET_STATE " and blocks PA main thread when the phone stream is moving to it. And I found module-echo-cancel’s message handler has not been called. So I think the IO thread (ALSA sink’s IO thread, right?) which shall call the message handler is also deadlocked. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Could anyone share some advice on the possible reason of this deadlock? How could I find out the where the IO thread is blocked by gdb? <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Here is the main thread stack on deadlock:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#1 0x4d8d28d5 in sem_wait () at ../nptl/sysdeps/unix/sysv/linux/i386/i486/sem_wait.S:80 ……. Here is the deadlock, when AEC filter sink update status to RUNNING<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#2 0x42684ad8 in pa_semaphore_wait (s=0x8ab5fd8) at pulsecore/semaphore-posix.c:63<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#3 0x4de0f94a in pa_asyncmsgq_send (a=0x8b3ba00, object=0x8ab5ff0, code=11, userdata=0x0, offset=0, chunk=0x0) at pulsecore/asyncmsgq.c:169<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#4 0x4de48ee9 in sink_set_state (s=<value optimized out>, state=<value optimized out>) at pulsecore/sink.c:415<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#5 0x4de459ec in pa_sink_input_finish_move (i=0x8b581b0, dest=0x8ab5ff0, save=false) at pulsecore/sink-input.c:1530 …………………… the phone input stream is moving to the AEC filter sink, triggered by module-filter-apply<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#6 0x4de464e7 in pa_sink_input_move_to (i=0x8b581b0, dest=0x8ab5ff0, save=false) at pulsecore/sink-input.c:1587<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#7 0xb6c44b02 in do_move (o=0x8b581b0, filter=<value optimized out>, restore=false, is_sink_input=true) at modules/module-filter-apply.c:192<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#8 move_object_for_filter (o=0x8b581b0, filter=<value optimized out>, restore=false, is_sink_input=true) at modules/module-filter-apply.c:217<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#9 0xb6c45d73 in process (u=0x8a8d0c8, o=<value optimized out>, is_sink_input=true) at modules/module-filter-apply.c:340<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#10 0x4de2607f in pa_hook_fire (hook=0x8a6f054, data=0x8b581b0) at pulsecore/hook-list.c:104<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#11 0x4de45aaf in pa_sink_input_finish_move (i=0x8b581b0, dest=0x8aa9af0, save=false) at pulsecore/sink-input.c:1539 ………………… the phone input stream is moving to the ALSA sink after the Bluetooth HSP sink disappears<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>#12 0x4de4c51d in pa_sink_move_all_finish (s=0x8aa9af0, q=0x8b63a58, save=false) at pulsecore/sink.c:740<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#13 0xb6c35da2 in card_set_profile (c=0x8aa7ac0, new_profile=0x8aa7940) at modules/alsa/module-alsa-card.c:352<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#14 0xb2a7da21 in restore_sco_card_default_profile (u=0x8b57e00) at modules/bluetooth/module-bluetooth-device.c:2073<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#15 stop_thread (u=0x8b57e00) at modules/bluetooth/module-bluetooth-device.c:2515<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#16 0xb2a7e8ab in module_bluetooth_device_LTX_pa__done (m=0x8b53540) at modules/bluetooth/module-bluetooth-device.c:3123<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#17 0x4de27b08 in pa_module_free (m=<value optimized out>) at pulsecore/module.c:165<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#18 0x4de2850d in defer_cb (api=0x8a6cc70, e=0x8b46a28, userdata=0x8a6ed90) at pulsecore/module.c:231<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#19 0x42b23a0b in dispatch_defer (m=0x8a6cc30) at pulse/mainloop.c:706<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#20 pa_mainloop_dispatch (m=0x8a6cc30) at pulse/mainloop.c:922<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#21 0x42b23e11 in pa_mainloop_iterate (m=0x8a6cc30, block=1, retval=0xbfa70228) at pulse/mainloop.c:962<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#22 0x42b23ee4 in pa_mainloop_run (m=0x8a6cc30, retval=0xbfa70228) at pulse/mainloop.c:977<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#23 0x08053b32 in main (argc=4, argv=0xbfa703f4) at daemon/main.c:1135<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks & Best Regards<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Amanda<o:p></o:p></span></p></div></body></html>