Hi Maxime,
Le 30 avril 2018 17:45:52 GMT+02:00, Maxime Coquelin
<maxime.coque...@redhat.com> a écrit :
>Hi Olivier,
>
>On 04/24/2018 04:46 PM, Olivier Matz wrote:
>> Some parts of dpdk use their own management threads. Most of the
>time,
>> the affinity of the thread is not properly set: it should not be
>scheduled
>> on the dataplane cores, because interrupting them can cause packet
>losses.
>>
>> This patchset introduces a new wrapper for thread creation that does
>> the job automatically, avoiding code duplication.
>>
>> v3:
>> * new patch: use this API in examples when relevant.
>> * replace pthread_kill by pthread_cancel. Note that pthread_join()
>> is still needed.
>> * rebase: vfio and pdump do not have control pthreads anymore, and
>eal
>> has 2 new pthreads
>> * remove all calls to snprintf/strlcpy that truncate the thread name:
>> all strings lengths are already < 16.
>>
>> v2:
>> * set affinity to master core if no core is off, as suggested by
>> Anatoly
>>
>> Olivier Matz (5):
>> eal: use sizeof to avoid a double use of a define
>> eal: new function to create control threads
>> eal: set name when creating a control thread
>> eal: set affinity for control threads
>> examples: use new API to create control threads
>>
>> drivers/net/kni/Makefile | 1 +
>> drivers/net/kni/rte_eth_kni.c | 3 +-
>> examples/tep_termination/main.c | 16 +++----
>> examples/vhost/main.c | 19 +++-----
>> lib/librte_eal/bsdapp/eal/eal.c | 4 +-
>> lib/librte_eal/bsdapp/eal/eal_thread.c | 2 +-
>> lib/librte_eal/common/eal_common_proc.c | 15 ++----
>> lib/librte_eal/common/eal_common_thread.c | 72
>++++++++++++++++++++++++++++
>> lib/librte_eal/common/include/rte_lcore.h | 26 ++++++++++
>> lib/librte_eal/linuxapp/eal/eal.c | 4 +-
>> lib/librte_eal/linuxapp/eal/eal_interrupts.c | 17 ++-----
>> lib/librte_eal/linuxapp/eal/eal_thread.c | 2 +-
>> lib/librte_eal/linuxapp/eal/eal_timer.c | 12 +----
>> lib/librte_eal/rte_eal_version.map | 1 +
>> lib/librte_vhost/socket.c | 25 ++--------
>> 15 files changed, 135 insertions(+), 84 deletions(-)
>>
>
>I face a deadlock issue with your series, that Jianfeng patch does not
>resolve ("eal: fix threads block on barrier"). Reverting the series and
>Jianfeng patch makes the issue to disappear.
>
>I face the problem in a VM (not seen on the host):
># ./install/bin/testpmd -l 0,1,2 --socket-mem 1024 -n 4 --proc-type
>auto
>--file-prefix pg -- --portmask=3 --forward-mode=macswap
>--port-topology=chained --disable-rss -i --rxq=1 --txq=1 --rxd=256
>--txd=256 --nb-cores=2 --auto-start
>EAL: Detected 3 lcore(s)
>EAL: Detected 1 NUMA nodes
>EAL: Auto-detected process type: PRIMARY
>EAL: Multi-process socket /var/run/.pg_unix
>
>
>Then it is stuck. Attaching with GDB, I get below backtrace
>information:
>
>(gdb) info threads
> Id Target Id Frame
> 3 Thread 0x7f63e1f9f700 (LWP 8808) "rte_mp_handle"
>0x00007f63e2591bfd in recvmsg () at
>../sysdeps/unix/syscall-template.S:81
> 2 Thread 0x7f63e179e700 (LWP 8809) "rte_mp_async"
>pthread_barrier_wait () at
>../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S:71
>* 1 Thread 0x7f63e32cec00 (LWP 8807) "testpmd" pthread_barrier_wait
>() at ../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S:71
>(gdb) bt full
>#0 pthread_barrier_wait () at
>../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S:71
>No locals.
>#1 0x0000000000520c54 in rte_ctrl_thread_create
>(thread=thread@entry=0x7ffe5c895020, name=name@entry=0x869d86
>"rte_mp_async", attr=attr@entry=0x0,
>start_routine=start_routine@entry=0x521030 <async_reply_handle>,
>arg=arg@entry=0x0)
> at /root/src/dpdk/lib/librte_eal/common/eal_common_thread.c:207
> params = 0x17b1e40
> lcore_id = <optimized out>
> cpuset = {__bits = {1, 0 <repeats 15 times>}}
> cpu_found = <optimized out>
> ret = 0
>#2 0x00000000005220b6 in rte_mp_channel_init () at
>/root/src/dpdk/lib/librte_eal/common/eal_common_proc.c:674
> path = "/var/run\000.pg_unix_*", '\000' <repeats 1301 times>...
> dir_fd = 4
> mp_handle_tid = 140066969745152
> async_reply_handle_tid = 140066961352448
>#3 0x000000000050c227 in rte_eal_init (argc=argc@entry=23,
>argv=argv@entry=0x7ffe5c896378) at
>/root/src/dpdk/lib/librte_eal/linuxapp/eal/eal.c:775
> i = <optimized out>
> fctret = 11
> ret = <optimized out>
> thread_id = 140066989861888
> run_once = {cnt = 1}
> logid = 0x17b1e00 "testpmd"
> cpuset = "T}\211\\\376\177", '\000' <repeats 117 times>,
>"\020", '\000' <repeats 116 times>...
> thread_name = "X}\211\\\376\177\000\000\226\301\036\342c\177\000"
> __func__ = "rte_eal_init"
>#4 0x0000000000473214 in main (argc=23, argv=0x7ffe5c896378) at
>/root/src/dpdk/app/test-pmd/testpmd.c:2597
> diag = <optimized out>
> port_id = <optimized out>
> ret = <optimized out>
> __func__ = "main"
>(gdb) thread 2
>[Switching to thread 2 (Thread 0x7f63e179e700 (LWP 8809))]
>#0 pthread_barrier_wait () at
>../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S:71
>71 cmpl %edx, (%rdi)
>(gdb) bt full
>#0 pthread_barrier_wait () at
>../nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S:71
>No locals.
>#1 0x0000000000520777 in rte_thread_init (arg=<optimized out>) at
>/root/src/dpdk/lib/librte_eal/common/eal_common_thread.c:156
> params = <optimized out>
> start_routine = 0x521030 <async_reply_handle>
> routine_arg = 0x0
>#2 0x00007f63e258add5 in start_thread (arg=0x7f63e179e700) at
>pthread_create.c:308
> __res = <optimized out>
> pd = 0x7f63e179e700
> now = <optimized out>
> unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140066961352448,
>1212869169857371576, 0, 8392704, 0, 140066961352448,
>-1291626103561052744, -1291619793368703560}, mask_was_saved = 0}}, priv
>
>= {pad = {0x0, 0x0, 0x0, 0x0}, data = {
> prev = 0x0, cleanup = 0x0, canceltype = 0}}}
> not_first_call = <optimized out>
> pagesize_m1 = <optimized out>
> sp = <optimized out>
> freesize = <optimized out>
>#3 0x00007f63e22b4b3d in clone () at
>../sysdeps/unix/sysv/linux/x86_64/clone.S:113
>No locals.
>(gdb) thread 3
>[Switching to thread 3 (Thread 0x7f63e1f9f700 (LWP 8808))]
>#0 0x00007f63e2591bfd in recvmsg () at
>../sysdeps/unix/syscall-template.S:81
>81 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
>(gdb) bt full
>#0 0x00007f63e2591bfd in recvmsg () at
>../sysdeps/unix/syscall-template.S:81
>No locals.
>#1 0x000000000052194e in read_msg (s=0x7f63e1f9d3b0, m=0x7f63e1f9d5a0)
>
>at /root/src/dpdk/lib/librte_eal/common/eal_common_proc.c:258
> msglen = <optimized out>
> control =
>"\000\000\000\000\000\000\000\000\336~\f\343c\177\000\000\005", '\000'
><repeats 23 times>, "\360\371\033\342c\177\000"
> cmsg = <optimized out>
> iov = {iov_base = 0x7f63e1f9d5a0, iov_len = 332}
> msgh = {msg_name = 0x7f63e1f9d3b0, msg_namelen = 110, msg_iov =
>0x7f63e1f9d370, msg_iovlen = 1, msg_control = 0x7f63e1f9d380,
>msg_controllen = 48, msg_flags = 0}
>#2 mp_handle (arg=<optimized out>) at
>/root/src/dpdk/lib/librte_eal/common/eal_common_proc.c:346
> msg = {type = 0, msg = {name = '\000' <repeats 63 times>,
>len_param = 0, num_fds = 0, param = '\000' <repeats 20 times>, "\002",
>'\000' <repeats 234 times>, fds = {0, 0, 0, 0, 0, 0, 0, 0}}}
> sa = {sun_family = 55104,
> sun_path =
>"\371\341c\177\000\000\352\372\f\343c\177\000\000\000\000\000\000\000\000\000\000\377\377\377\377\377\377\377\377\000\367\371\341c\177\000\000\030\000\000\000\000\000\000\000p\327\371\341c\177\000\000\000\367\371\341c\177\000\000\000\367\371\341c\177",
>
>'\000' <repeats 34 times>, "\200\037\000\000\377\377"}
>#3 0x00007f63e258add5 in start_thread (arg=0x7f63e1f9f700) at
>pthread_create.c:308
> __res = <optimized out>
> pd = 0x7f63e1f9f700
> now = <optimized out>
> unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140066969745152,
>1212869169857371576, 0, 8392704, 0, 140066969745152,
>-1291625004586295880, -1291619793368703560}, mask_was_saved = 0}}, priv
>
>= {pad = {0x0, 0x0, 0x0, 0x0}, data = {
> prev = 0x0, cleanup = 0x0, canceltype = 0}}}
> not_first_call = <optimized out>
> pagesize_m1 = <optimized out>
> sp = <optimized out>
> freesize = <optimized out>
>#4 0x00007f63e22b4b3d in clone () at
>../sysdeps/unix/sysv/linux/x86_64/clone.S:113
>No locals.
>
>I don't have more info for now.
>
Thanks for the feedback on this issue. I don't see obvious reason for this
deadlock yet.
I'll investigate it asap (not tomorrow, but wednesday). In the worst case, we
can revert the series if I cannot find the root cause rapidly.
Olivier
