[Qemu-devel] coroutine: hung when using gthread backend

[Wenchao Xia]

  When I using tcg with coroutine backend = gthread,
x86_64-softmmu/qemu-system-x86_64 will hung. Any one
working on it?

System: RH6.3
gdb:

Reading symbols from
/home/xiawenc/Workdir/Src/qemu/build/master/x86_64-softmmu/qemu-system-x86_64...done.
(gdb) r
Starting program:
/home/xiawenc/Workdir/Src/qemu/build/master/x86_64-softmmu/qemu-system-x86_64

[Thread debugging using libthread_db enabled]
[New Thread 0x7fffecd5c700 (LWP 971)]
[New Thread 0x7fffe415a700 (LWP 972)]
[New Thread 0x7fffe3759700 (LWP 973)]
[Thread 0x7fffe415a700 (LWP 972) exited]
[Thread 0x7fffe3759700 (LWP 973) exited]
^C
Program received signal SIGINT, Interrupt.
0x00007ffff60f843c in pthread_cond_wait@@GLIBC_2.3.2 ()
   from /lib64/libpthread.so.0
Missing separate debuginfos, use: debuginfo-install
SDL-1.2.14-3.el6.x86_64 cyrus-sasl-lib-2.1.23-13.el6.x86_64
glib2-2.22.5-7.el6.x86_64 glibc-2.12-1.80.el6.x86_64
gnutls-2.8.5-4.el6_2.2.x86_64 keyutils-libs-1.4-4.el6.x86_64
krb5-libs-1.9-33.el6.x86_64 libX11-1.3-2.el6.x86_64
libXau-1.0.5-1.el6.x86_64 libcom_err-1.41.12-12.el6.x86_64
libcurl-7.19.7-26.el6_2.4.x86_64 libgcrypt-1.4.5-9.el6_2.2.x86_64
libgpg-error-1.7-4.el6.x86_64 libidn-1.18-2.el6.x86_64
libjpeg-6b-46.el6.x86_64 libpng-1.2.49-1.el6_2.x86_64
libselinux-2.0.94-5.3.el6.x86_64 libssh2-1.2.2-7.el6_2.3.x86_64
libtasn1-2.3-3.el6_2.1.x86_64 libuuid-2.17.2-12.7.el6.x86_64
libxcb-1.5-1.el6.x86_64 ncurses-libs-5.7-3.20090208.el6.x86_64
nspr-4.9-1.el6.x86_64 nss-3.13.3-6.el6.x86_64
nss-softokn-freebl-3.12.9-11.el6.x86_64 nss-util-3.13.3-2.el6.x86_64
openldap-2.4.23-26.el6.x86_64 openssl-1.0.0-20.el6_2.5.x86_64
pixman-0.18.4-1.el6_0.1.x86_64 zlib-1.2.3-27.el6.x86_64
(gdb) thread
[Current thread is 1 (Thread 0x7ffff7bf7940 (LWP 965))]
(gdb) info thread
  2 Thread 0x7fffecd5c700 (LWP 971)  0x00007ffff60f843c in
pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
* 1 Thread 0x7ffff7bf7940 (LWP 965)  0x00007ffff60f843c in
pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
(gdb) bt
#0  0x00007ffff60f843c in pthread_cond_wait@@GLIBC_2.3.2 ()
   from /lib64/libpthread.so.0
#1  0x00007ffff7ce73c8 in coroutine_wait_runnable_locked (co=0x7ffff8be4f30)
    at /home/xiawenc/Workdir/Src/qemu/qemu/coroutine-gthread.c:133
#2  0x00007ffff7ce74a8 in qemu_coroutine_switch (from_=0x7ffff8be4f30, to_=
    0x7ffff8be7b30, action=COROUTINE_YIELD)
    at /home/xiawenc/Workdir/Src/qemu/qemu/coroutine-gthread.c:191
#3  0x00007ffff7ddc092 in coroutine_swap (from=<value optimized out>, to=
    0x7ffff8be7b30) at
/home/xiawenc/Workdir/Src/qemu/qemu/qemu-coroutine.c:72
#4  0x00007ffff7cb8c05 in bdrv_rw_co (bs=0x7ffff8bcda60,
    sector_num=<value optimized out>, buf=<value optimized out>,
    nb_sectors=<value optimized out>, is_write=<value optimized out>)
    at /home/xiawenc/Workdir/Src/qemu/qemu/block.c:2171
#5  0x00007ffff7d615f7 in pflash_cfi01_init (dev=0x7ffff8bd0e60)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/pflash_cfi01.c:583
#6  0x00007ffff7d66a76 in device_realize (dev=0x7ffff8bd0e60, err=
    0x7fffffffd9a0) at /home/xiawenc/Workdir/Src/qemu/qemu/hw/qdev.c:175
#7  0x00007ffff7d671b7 in device_set_realized (obj=0x7ffff8bd0e60,
value=true,
    err=0x7fffffffdaa0) at /home/xiawenc/Workdir/Src/qemu/qemu/hw/qdev.c:673
#8  0x00007ffff7de824e in property_set_bool (obj=0x7ffff8bd0e60,
    v=<value optimized out>, opaque=0x7ffff8be4ae0,
    name=<value optimized out>, errp=0x7fffffffdaa0)
    at /home/xiawenc/Workdir/Src/qemu/qemu/qom/object.c:1224
---Type <return> to continue, or q <return> to quit---
#9  0x00007ffff7dea765 in object_property_set_qobject (obj=0x7ffff8bd0e60,
    value=<value optimized out>, name=0x7ffff7f5ab27 "realized", errp=
    0x7fffffffdaa0) at
/home/xiawenc/Workdir/Src/qemu/qemu/qom/qom-qobject.c:24
#10 0x00007ffff7de8cbe in object_property_set_bool (obj=0x7ffff8bd0e60,
    value=<value optimized out>, name=0x7ffff7f5ab27 "realized", errp=
    0x7fffffffdaa0) at /home/xiawenc/Workdir/Src/qemu/qemu/qom/object.c:767
#11 0x00007ffff7d67efa in qdev_init (dev=0x7ffff8bd0e60)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/qdev.c:161
#12 0x00007ffff7d67f91 in qdev_init_nofail (dev=0x7ffff8bd0e60)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/qdev.c:261
#13 0x00007ffff7d60b6e in pflash_cfi01_register (base=4294836224,
    qdev=<value optimized out>, name=0x7ffff7f78604 "system.flash",
    size=<value optimized out>, bs=0x7ffff8bcda60, sector_len=4096,
nb_blocs=
    32, width=1, id0=0, id1=0, id2=0, id3=0, be=0)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/pflash_cfi01.c:752
#14 0x00007ffff7e52154 in pc_system_flash_init (rom_memory=0x7ffff8be7250)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/i386/../pc_sysfw.c:134
#15 pc_system_firmware_init (rom_memory=0x7ffff8be7250)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/i386/../pc_sysfw.c:234
#16 0x00007ffff7e58b73 in pc_memory_init (system_memory=0x7ffff8badd50,
    kernel_filename=0x0, kernel_cmdline=0x7ffff7f87af2 "", initrd_filename=
    0x0, below_4g_mem_size=134217728, above_4g_mem_size=0, rom_memory=
    0x7ffff8be7250, ram_memory=0x7fffffffdcf0)
---Type <return> to continue, or q <return> to quit---
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/i386/pc.c:948
#17 0x00007ffff7e590e7 in pc_init1 (system_memory=0x7ffff8badd50, system_io=
    0x7ffff8baea20, ram_size=134217728, boot_device=0x7ffff7f5560b "cad",
    kernel_filename=0x0, kernel_cmdline=0x7ffff7f87af2 "", initrd_filename=
    0x0, cpu_model=0x0, pci_enabled=1, kvmclock_enabled=1)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/i386/pc_piix.c:115
#18 0x00007ffff7e59800 in pc_init_pci (args=<value optimized out>)
    at /home/xiawenc/Workdir/Src/qemu/qemu/hw/i386/pc_piix.c:230
#19 0x00007ffff7e1e8db in main (argc=<value optimized out>,
    argv=<value optimized out>, envp=<value optimized out>)
    at /home/xiawenc/Workdir/Src/qemu/qemu/vl.c:4306
(gdb) thread 2
[Switching to thread 2 (Thread 0x7fffecd5c700 (LWP 971))]#0
0x00007ffff60f843c in pthread_cond_wait@@GLIBC_2.3.2 () from
/lib64/libpthread.so.0
(gdb) bt
#0  0x00007ffff60f843c in pthread_cond_wait@@GLIBC_2.3.2 ()
   from /lib64/libpthread.so.0
#1  0x00007ffff7f2f739 in qemu_cond_wait (cond=<value optimized out>,
    mutex=<value optimized out>)
    at /home/xiawenc/Workdir/Src/qemu/qemu/util/qemu-thread-posix.c:116
#2  0x00007ffff7e2845c in qemu_tcg_cpu_thread_fn (arg=<value optimized out>)
    at /home/xiawenc/Workdir/Src/qemu/qemu/cpus.c:834
#3  0x00007ffff60f4851 in start_thread () from /lib64/libpthread.so.0
#4  0x00007ffff3de567d in clone () from /lib64/libc.so.6

-- 
Best Regards

Wenchao Xia