On 21 Apr 2005 Stefan Huelswitt <s.huelswitt at gmx.de> wrote:
>> Markku Tavasti wrote:
>>
>> With version 0.9.12 of the plugin I get the following (Intel Celeron
>> 433Mhz, output via OSS, black background) :
>> - Only stable when playing streams over network.
>> - Always crashes (well VDR takes 99% of CPU time) when playing songs
>> from harddrive which are "new"
>> (ie. no id3-tag got scanned). The next time the song gets played it
>> works, besides this :
>> - Frequent crashes when changing songs from harddrive (again, VDR takes
>> 99% of CPU time),
>>
>> AFAIS, the plugin got some ugly race conditions concering threads.
>
>This might be possible, but I don't know how to debug this as
>nothing of it happens on my machine (playing a lot song from
>harddisc, right now for 6 hours continiously).
>
>My suggestion is that somebody with that problem, please wait
>until vdr hangs with 100% cpu and then hook gdb to this process
>to see which thread it is and where it hangs.
>
>I'm sorry, but I'm currently rather busy with other stuff, so
>that I cannot spent time on this myself. I'm be back on this in a
>week or two...
>
Hi,
first, my apologies for my really late reply.
Back to the problem above: I did a backtrace with gdb, and it seems the
plugin itself isn't the problem (my setup?),
read() blocks infinitely trying to read the mp3-file. I don't know why
and I'm asking for your help/comments.
Oh, here's the backtrace:
(gdb) thread 2
[Switching to thread 2 (Thread -1320977488 (LWP 4039))]#0 0xb7f796a1 in
__read_nocancel () from /lib/tls/libpthread.so.0
(gdb) bt
#0 0xb7f796a1 in __read_nocancel () from /lib/tls/libpthread.so.0
#1 0xb76cc58c in cStream::Stream (this=0x93610c8, data=@0xb1427618,
len=@0xb142761c, rest=0x93611d0 "") at stream.c:271
#2 0xb76d30e6 in cScanID3::DoScan (this=0x9361170) at decoder-mp3.c:39
#3 0xb76d1f6e in cMP3Decoder::Start (this=0x935f7a8) at decoder-mp3.c:159
#4 0xb76cae7d in cMP3Player::Action (this=0x9360580) at player-mp3.c:1798
#5 0x080ef2a2 in cThread::StartThread ()
#6 0xb7f74b63 in start_thread () from /lib/tls/libpthread.so.0
#7 0xb7e2918a in clone () from /lib/tls/libc.so.6
(gdb) *sigh*
Today I tried to set O_NONBLOCK to the open()-calls (the code does a
"do{ r = read(...); }while(r!=-1 && r != EINTR);" at stream.c:271 so
this works out-of-the-box), then again I tried a select() on the
filedescriptor before stream.c:271. None of the mentioned worked.
I can comment out the call to doScan() in cMP3Player::Action to avoid
scanning id3-tags. This makes the plugin work without id3-tags though
(as one might expect...).
That's all I can think of for now, if you need more information, please
let me know.
--
---
Regards,
Martin Cap
