o5r/plan9port
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

libthread: abort on single-threaded lock contention

Browse source
This commit is contained in:
Russ Cox 2008-07-09 11:41:14 -04:00
parent f35a04866f
commit faf1fb6c7e
1 changed files with 24 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

24
src/libthread/thread.c
View file

@ -463,6 +463,12 @@ needstack(int n)
}
}
static int
singlethreaded(void)
{
return threadnproc == 1 && _threadprocs->nthread == 1;
}
/*
* locking
*/
@ -481,6 +487,12 @@ threadqlock(QLock *l, int block, ulong pc)
unlock(&l->l);
return 0;
}
if(singlethreaded()){
fprint(2, "qlock deadlock\n");
abort();
}
/*print("qsleep %p @%#x by %p\n", l, pc, (*threadnow)()); */
addthread(&l->waiting, (*threadnow)());
unlock(&l->l);
@ -537,6 +549,10 @@ threadrlock(RWLock *l, int block, ulong pc)
unlock(&l->l);
return 0;
}
if(singlethreaded()){
fprint(2, "rlock deadlock\n");
abort();
}
addthread(&l->rwaiting, (*threadnow)());
unlock(&l->l);
_threadswitch();
@ -558,6 +574,10 @@ threadwlock(RWLock *l, int block, ulong pc)
unlock(&l->l);
return 0;
}
if(singlethreaded()){
fprint(2, "wlock deadlock\n");
abort();
}
addthread(&l->wwaiting, (*threadnow)());
unlock(&l->l);
_threadswitch();
@ -613,6 +633,10 @@ threadwunlock(RWLock *l, ulong pc)
static void
threadrsleep(Rendez *r, ulong pc)
{
if(singlethreaded()){
fprint(2, "rsleep deadlock\n");
abort();
}
addthread(&r->waiting, proc()->thread);
qunlock(r->l);
_threadswitch();