Re: NSRunLoop busy wait problem

[Stephen Brandon]

On Wednesday 20 February 2002 09:40, Richard Frith-Macdonald wrote:

> Barring errors on my part, the effect of the change should be that
> acceptInputForMode:beforeDate: should now block until the specified
> date/time even if no I/O is possible.  Previously it would return
> immediately.  This seems to be the way it works on MacOS-X

Tracing my bug a little further - a deadlock condition has occurred in a 
NSLog statement inside a -compare method. We have various locks on different 
objects, so it's possible one of those is involved, but I'm not convinced. 
But looking through all the recent gnustep-base changes I can't see what 
would have triggered it. But the logging was working perfectly last night 
before my gnustep cvs update this morning.

[performancesArray removeObject: p];
calls:  _i_GSMutableArray__removeObject_
calls: _i_SndPerformance__isEqual_
which contains my debug statement: NSLog(@"checking if equal %@ vs. %@ = 
%s\n", self, anotherPerformance, equal ? "YES" :"NO");

and from there:

#0  0x407aab85 in __sigsuspend (set=0x41be950c) at 
../sysdeps/unix/sysv/linux/sigsuspend.c:45
#1  0x4076c1c9 in __pthread_wait_for_restart_signal (self=0x41be9be0) at 
pthread.c:969
#2  0x4076df09 in __pthread_alt_lock (lock=0x80c8200, self=0x0) at 
restart.h:34
#3  0x4076ad16 in __pthread_mutex_lock (mutex=0x80c81f0) at mutex.c:120
#4  0x4066e47f in __objc_mutex_lock ()
   from /usr/GNUstep/System/Libraries/ix86/linux-gnu/libobjc.so.1
#5  0x4066e9d9 in objc_mutex_lock ()
   from /usr/GNUstep/System/Libraries/ix86/linux-gnu/libobjc.so.1
#6  0x4058137f in _i_NSRecursiveLock__lock (self=0x80c6f90, _cmd=0x40659420) 
at NSLock.m:543
#7  0x405d8b6b in NSZoneFromPointer ()
   from 
/usr/GNUstep/System/Libraries/ix86/linux-gnu/gnu-gnu-gnu/libgnustep-base.so.1
#8  0x405145de in _i_GSString__dealloc ()
   from 
/usr/GNUstep/System/Libraries/ix86/linux-gnu/gnu-gnu-gnu/libgnustep-base.so.1
#9  0x405917ce in _i_NSObject__release (self=0x80e51a0, _cmd=0x40633130) at 
NSObject.m:1081
#10 0x4053f413 in _i_NSAutoreleasePool__dealloc ()
   from 
/usr/GNUstep/System/Libraries/ix86/linux-gnu/gnu-gnu-gnu/libgnustep-base.so.1
#11 0x4053f37e in _i_NSAutoreleasePool__release ()
   from 
/usr/GNUstep/System/Libraries/ix86/linux-gnu/gnu-gnu-gnu/libgnustep-base.so.1
#12 0x40581852 in NSLogv (format=0x40366adc, args=0x41be9830) at NSLog.m:160
#13 0x4058158c in NSLog (format=0x40366adc) at NSLog.m:109


Still investigating.

Cheers,
Stephen