On Fri, 2020-09-25 at 14:00 +0800, Chengyi Zhao wrote: > Hi guys, > > Pulseaudio is deadlocked when Bluetooth(HSP) is selected as the input > audio and module-echo-cancel is loaded. > > I don't know why Thread 1 and Thread 5 are all blocked in the function > futex_abstimed_wait_cancelable. > > Please help analyze the following call stack information, thanks! > > (gdb) info thread > Id Target Id Frame > * 1 Thread 0x7f7f23817e00 (LWP 4366) "pulseaudio" > futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, > futex_word=0x7f7f0c0013e0) at > ../sysdeps/unix/sysv/linux/futex-internal.h:205 > 2 Thread 0x7f7f18818700 (LWP 4601) "alsa-sink-ALC89" > 0x00007f7f23feb926 in __GI_ppoll (fds=0x5cc130, nfds=4, > timeout=<optimized out>, sigmask=sigmask@entry=0x0) at > ../sysdeps/unix/sysv/linux/ppoll.c:39 > 3 Thread 0x7f7f13fa8700 (LWP 4604) "alsa-source-ALC" > 0x00007f7f23feb926 in __GI_ppoll (fds=0x7940c0, nfds=4, > timeout=<optimized out>, sigmask=sigmask@entry=0x0) at > ../sysdeps/unix/sysv/linux/ppoll.c:39 > 5 Thread 0x7f7f13227700 (LWP 6227) "bluetooth" > futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, > futex_word=0x667650) at ../sysdeps/unix/sysv/linux/futex-internal.h:205 > (gdb) bt > #0 0x00007f7f24260896 in futex_abstimed_wait_cancelable (private=0, > abstime=0x0, expected=0, futex_word=0x7f7f0c0013e0) at > ../sysdeps/unix/sysv/linux/futex-internal.h:205 > #1 0x00007f7f24260896 in do_futex_wait (sem=sem@entry=0x7f7f0c0013e0, > abstime=0x0) at sem_waitcommon.c:111 > #2 0x00007f7f24260988 in __new_sem_wait_slow > (sem=sem@entry=0x7f7f0c0013e0, abstime=0x0) at sem_waitcommon.c:181 > #3 0x00007f7f242609f9 in __new_sem_wait (sem=sem@entry=0x7f7f0c0013e0) > at sem_wait.c:42 > #4 0x00007f7f243846d2 in pa_semaphore_wait (s=0x7f7f0c0013e0) at > pulsecore/semaphore-posix.c:61 > #5 0x00007f7f243cc224 in pa_asyncmsgq_send (a=0x717130, > object=<optimized out>, code=code@entry=13, > userdata=userdata@entry=0x697810, offset=offset@entry=0, > chunk=chunk@entry=0x0) at pulsecore/asyncmsgq.c:168 > #6 0x00007f7f1f1f5dfe in command_get_playback_latency (pd=<optimized > out>, command=<optimized out>, tag=9, t=<optimized out>, > userdata=<optimized out>) at pulsecore/protocol-native.c:2873 > #7 0x00007f7f2436df7f in pa_pdispatch_run (pd=0x5c9650, > packet=packet@entry=0x6f84c0, ancil_data=ancil_data@entry=0x6e0158, > userdata=userdata@entry=0x6f4600) at pulsecore/pdispatch.c:346 > #8 0x00007f7f1f1f95e5 in pstream_packet_callback (p=0x6dfec0, > packet=0x6f84c0, ancil_data=0x6e0158, userdata=0x6f4600) at > pulsecore/protocol-native.c:4951 > #9 0x00007f7f2437098d in do_read (p=p@entry=0x6dfec0, > re=re@entry=0x6e0088) at pulsecore/pstream.c:1020 > #10 0x00007f7f24373758 in do_pstream_read_write (p=0x6dfec0) at > pulsecore/pstream.c:253 > #11 0x00007f7f24373af9 in srb_callback (srb=0x756d90, userdata=0x6dfec0) > at pulsecore/pstream.c:295 > #12 0x00007f7f2437434a in srbchannel_rwloop (sr=0x756d90) at > pulsecore/srbchannel.c:190 > #13 0x00007f7f242fed28 in dispatch_pollfds (m=0x5cc840) at > pulse/mainloop.c:140 > #14 0x00007f7f242fed28 in pa_mainloop_dispatch (m=m@entry=0x5cc840) at > pulse/mainloop.c:898 > #15 0x00007f7f242feffc in pa_mainloop_iterate (m=0x5cc840, > block=<optimized out>, retval=0x7ffceef8cde8) at pulse/mainloop.c:929 > #16 0x00007f7f242ff0a0 in pa_mainloop_run (m=m@entry=0x5cc840, > retval=retval@entry=0x7ffceef8cde8) at pulse/mainloop.c:945 > #17 0x0000000000407306 in main (argc=<optimized out>, argv=<optimized > out>) at daemon/main.c:1144 > (gdb) c > Continuing. > ^C > Thread 1 "pulseaudio" received signal SIGINT, Interrupt. > futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, > futex_word=0x7f7f0c0013e0) at > ../sysdeps/unix/sysv/linux/futex-internal.h:205 > 205 in ../sysdeps/unix/sysv/linux/futex-internal.h > (gdb) info thread > Id Target Id Frame > * 1 Thread 0x7f7f23817e00 (LWP 4366) "pulseaudio" > futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, > futex_word=0x7f7f0c0013e0) at > ../sysdeps/unix/sysv/linux/futex-internal.h:205 > 2 Thread 0x7f7f18818700 (LWP 4601) "alsa-sink-ALC89" > 0x00007f7f23feb926 in __GI_ppoll (fds=0x5cc130, nfds=4, > timeout=<optimized out>, sigmask=sigmask@entry=0x0) at > ../sysdeps/unix/sysv/linux/ppoll.c:39 > 3 Thread 0x7f7f13fa8700 (LWP 4604) "alsa-source-ALC" > 0x00007f7f23feb926 in __GI_ppoll (fds=0x7940c0, nfds=4, > timeout=<optimized out>, sigmask=sigmask@entry=0x0) at > ../sysdeps/unix/sysv/linux/ppoll.c:39 > 5 Thread 0x7f7f13227700 (LWP 6227) "bluetooth" > futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, > futex_word=0x667650) at ../sysdeps/unix/sysv/linux/futex-internal.h:205 > (gdb) thread 5 > [Switching to thread 5 (Thread 0x7f7f13227700 (LWP 6227))] > #0 futex_abstimed_wait_cancelable (private=0, abstime=0x0, expected=0, > futex_word=0x667650) at ../sysdeps/unix/sysv/linux/futex-internal.h:205 > 205 in ../sysdeps/unix/sysv/linux/futex-internal.h > (gdb) bt > #0 0x00007f7f24260896 in futex_abstimed_wait_cancelable (private=0, > abstime=0x0, expected=0, futex_word=0x667650) at > ../sysdeps/unix/sysv/linux/futex-internal.h:205 > #1 0x00007f7f24260896 in do_futex_wait (sem=sem@entry=0x667650, > abstime=0x0) at sem_waitcommon.c:111 > #2 0x00007f7f24260988 in __new_sem_wait_slow (sem=sem@entry=0x667650, > abstime=0x0) at sem_waitcommon.c:181 > #3 0x00007f7f242609f9 in __new_sem_wait (sem=sem@entry=0x667650) at > sem_wait.c:42 > #4 0x00007f7f243846d2 in pa_semaphore_wait (s=0x667650) at > pulsecore/semaphore-posix.c:61 > #5 0x00007f7f243cc224 in pa_asyncmsgq_send (a=0x717130, > object=object@entry=0x73ce10, code=code@entry=0, > userdata=userdata@entry=0x7f7f132265e0, offset=offset@entry=0, > chunk=chunk@entry=0x0) > at pulsecore/asyncmsgq.c:168 > #6 0x00007f7f1334c123 in do_resync (u=0x756b30) at > ./pulsecore/msgobject.h:44 > #7 0x00007f7f1334c123 in source_output_push_cb (o=<optimized out>, > chunk=<optimized out>) at modules/echo-cancel/module-echo-cancel.c:925 > #8 0x00007f7f244112b7 in pa_source_output_push (o=o@entry=0x6fbee0, > chunk=chunk@entry=0x7f7f13226830) at pulsecore/source-output.c:833 > #9 0x00007f7f24419bca in pa_source_post (s=0x75f840, > chunk=chunk@entry=0x7f7f13226830) at pulsecore/source.c:989 > #10 0x00007f7f13260339 in sco_process_push (u=u@entry=0x76d990) at > modules/bluetooth/module-bluez5-device.c:408 > #11 0x00007f7f13261a56 in thread_func (userdata=<optimized out>) at > modules/bluetooth/module-bluez5-device.c:1556 > #12 0x00007f7f24384478 in internal_thread_func (userdata=0x686460) at > pulsecore/thread-posix.c:81 > #13 0x00007f7f24257fa3 in start_thread (arg=<optimized out>) at > pthread_create.c:486 > #14 0x00007f7f23ff64df in clone () at > ../sysdeps/unix/sysv/linux/x86_64/clone.S:95 > (gdb) It seems that do_resync() in module-echo-cancel.c assumes that the source and sink run in separate threads, but the HSP sink and source run in the same thread. do_resync() sends a message from the source thread to the sink thread with pa_asyncmsgq_send(), which blocks until the message is processed, but the sink thread never processes the message, because it's the same thread as the source thread, which is currently blocked in pa_asyncmsgq_send(). -- Tanu https://www.patreon.com/tanuk https://liberapay.com/tanuk _______________________________________________ pulseaudio-discuss mailing list pulseaudio-discuss@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss
