Re: (ITS#5257) test008 hanging in bdb

[hyc@symas.com]

h.b.furuseth@usit.uio.no wrote:
> Hah.  thr_debug found it (at least I presume it's the same bug) after 70
> iterations over test008.
> 
> Compiled with
> 	CPPFLAGS='-DLDAP_THREAD_DEBUG -DLDAP_REL_ENG' CFLAGS='-O0 -g'
> run with export LDAP_THREAD_DEBUG=nocount
> 
> backtrace and testrun directory:
>    http://folk.uio.no/hbf/test008bug-071204.tbz
> 
> slapd.1.log ends with:
> 
> ====> bdb_cache_delete( 146 )
> thr_debug.c:1024: ldap_pvt_thread_mutex_unlock error: !THREAD_MUTEX_OWNER( mutex )
> 
> The mutex owner is ldap_debug_thread_none, i.e. the mutex is not locked.
> 
> It's cache.c:874:bdb_cache_entryinfo_unlock( *eip ); in bdb_cache_find_id().
> #3  0x00000000004e1df9 in bdb_cache_find_id (op=0x1ebb46a0, tid=0x0, id=4, eip=0x45809ad0, flag=1, locker=38,
>     lock=0x45809b20) at cache.c:874
> 
> 
> I had to patch thr_posix.c a bit to detect Linux NPTL threads:
> 
> diff -u -2 -r1.50 thr_posix.c
> --- thr_posix.c	25 Oct 2007 04:42:40 -0000	1.50
> +++ thr_posix.c	4 Dec 2007 23:06:29 -0000
> @@ -45,6 +45,6 @@
>  #ifdef LDAP_THREAD_DEBUG
>  #  if defined LDAP_INT_THREAD_MUTEXATTR	/* May be defined in CPPFLAGS */
> -#  elif defined HAVE_PTHREAD_KILL_OTHER_THREADS_NP
> -	 /* LinuxThreads hack */
> +#  elif 1 || defined HAVE_PTHREAD_KILL_OTHER_THREADS_NP
> +	 /* LinuxThreads and NPTL hack */
>  #    define LDAP_INT_THREAD_MUTEXATTR	PTHREAD_MUTEX_ERRORCHECK_NP
>  #  else

Ah, that one actually makes sense. Fix in HEAD. Unfortunately, this code path 
is only being triggered because of the other bug, it's not the root cause.

-- 
   -- Howard Chu
   Chief Architect, Symas Corp.  http://www.symas.com
   Director, Highland Sun        http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP     http://www.openldap.org/project/