diff --git a/sys/src/libthread/channel.c b/sys/src/libthread/channel.c
index 4e410aa94..6b736f7d9 100644
--- a/sys/src/libthread/channel.c
+++ b/sys/src/libthread/channel.c
@@ -339,15 +339,7 @@ nbsend(Channel *c, void *v)
 	return runop(CHANSND, c, v, 1);
 }
 
-static void
-channelsize(Channel *c, int sz)
-{
-	if(c->e != sz){
-		fprint(2, "expected channel with elements of size %d, got size %d\n",
-			sz, c->e);
-		abort();
-	}
-}
+#define channelsize(c, sz)	assert(c->e == sz)
 
 int
 sendul(Channel *c, ulong v)
diff --git a/sys/src/libthread/debug.c b/sys/src/libthread/debug.c
index 183869d18..cab101ca6 100644
--- a/sys/src/libthread/debug.c
+++ b/sys/src/libthread/debug.c
@@ -6,16 +6,13 @@
 int _threaddebuglevel;
 
 void
-_threaddebug(ulong flag, char *fmt, ...)
+_threadprint(char *fmt, ...)
 {
 	char buf[128];
 	va_list arg;
 	Fmt f;
 	Proc *p;
 
-	if((_threaddebuglevel&flag) == 0)
-		return;
-
 	fmtfdinit(&f, 2, buf, sizeof buf);
 
 	p = _threadgetproc();
@@ -36,16 +33,6 @@ _threaddebug(ulong flag, char *fmt, ...)
 void
 _threadassert(char *s)
 {
-	char buf[256];
-	int n;
-	Proc *p;
-
-	p = _threadgetproc();
-	if(p && p->thread)
-		n = sprint(buf, "%d.%d ", p->pid, p->thread->id);
-	else
-		n = 0;
-	snprint(buf+n, sizeof(buf)-n, "%s: assertion failed\n", s);
-	write(2, buf, strlen(buf));
+	_threadprint("%s: assertion failed", s);
 	abort();
 }
diff --git a/sys/src/libthread/main.c b/sys/src/libthread/main.c
index faa08bf79..7f88c17bc 100644
--- a/sys/src/libthread/main.c
+++ b/sys/src/libthread/main.c
@@ -3,59 +3,41 @@
 #include <thread.h>
 #include "threadimpl.h"
 
-typedef struct Mainarg Mainarg;
-struct Mainarg
-{
-	int	argc;
-	char	**argv;
-};
-
-int	mainstacksize;
-static jmp_buf _mainjmp;
-static void mainlauncher(void*);
 extern void (*_sysfatal)(char*, va_list);
 extern void (*__assert)(char*);
 
-static Proc **mainp;
+int	mainstacksize;
+
+static jmp_buf mainjmp;
+static int mainargc;
+
+static void
+mainlauncher(void *arg)
+{
+	threadmain(mainargc, arg);
+	threadexits("threadmain");
+}
 
 void
 main(int argc, char **argv)
 {
-	Mainarg *a;
-	Proc *p;
-
 	rfork(RFREND);
-	mainp = &p;
 
 //_threaddebuglevel = (DBGSCHED|DBGCHAN|DBGREND)^~0;
-	_systhreadinit();
+	_threadprocp = privalloc();
 	_qlockinit(_threadrendezvous);
 	_sysfatal = _threadsysfatal;
 	__assert = _threadassert;
 	notify(_threadnote);
 	if(mainstacksize == 0)
 		mainstacksize = 8*1024;
-
-	a = _threadmalloc(sizeof *a, 1);
-	a->argc = argc;
-	a->argv = argv;
-
-	p = _newproc(mainlauncher, a, mainstacksize, "threadmain", 0, 0);
-	setjmp(_mainjmp);
-	_schedinit(p);
+	mainargc = argc;
+	_threadsetproc(_newproc(mainlauncher, argv, mainstacksize, "threadmain", 0, 0));
+	setjmp(mainjmp);
+	_schedinit();
 	abort();	/* not reached */
 }
 
-static void
-mainlauncher(void *arg)
-{
-	Mainarg *a;
-
-	a = arg;
-	threadmain(a->argc, a->argv);
-	threadexits("threadmain");
-}
-
 static void
 efork(Execargs *e)
 {
@@ -93,8 +75,8 @@ _schedfork(Proc *p)
 
 	switch(pid = rfork(RFPROC|RFMEM|RFNOWAIT|p->rforkflag)){
 	case 0:
-		*mainp = p;	/* write to stack, so local to proc */
-		longjmp(_mainjmp, 1);
+		_threadsetproc(p);
+		longjmp(mainjmp, 1);
 	default:
 		return pid;
 	}
@@ -141,23 +123,3 @@ _schedexecwait(void)
 	}
 	threadexits("procexec");
 }
-
-static Proc **procp;
-
-void
-_systhreadinit(void)
-{
-	procp = privalloc();
-}
-
-Proc*
-_threadgetproc(void)
-{
-	return *procp;
-}
-
-void
-_threadsetproc(Proc *p)
-{
-	*procp = p;
-}
diff --git a/sys/src/libthread/note.c b/sys/src/libthread/note.c
index c04e3e1a2..fcbbf8c07 100644
--- a/sys/src/libthread/note.c
+++ b/sys/src/libthread/note.c
@@ -72,7 +72,7 @@ delayednotes(Proc *p, void *v)
 					break;
 			}
 			if(i==NFN){
-				_threaddebug(DBGNOTE, "Unhandled note %s, proc %p\n", n->s, p);
+				_threaddebug(DBGNOTE, "Unhandled note %s, proc %p", n->s, p);
 				if(v != nil)
 					noted(NDFLT);
 				else if(strncmp(n->s, "sys:", 4)==0)
@@ -94,7 +94,7 @@ _threadnote(void *v, char *s)
 		noted(NDFLT);
 
 	if(_threadexitsallstatus){
-		_threaddebug(DBGNOTE, "Threadexitsallstatus = '%s'\n", _threadexitsallstatus);
+		_threaddebug(DBGNOTE, "Threadexitsallstatus = '%s'", _threadexitsallstatus);
 		_exits(_threadexitsallstatus);
 	}
 
diff --git a/sys/src/libthread/sched.c b/sys/src/libthread/sched.c
index 888d64cc2..6e7a6d57a 100644
--- a/sys/src/libthread/sched.c
+++ b/sys/src/libthread/sched.c
@@ -36,14 +36,13 @@ unlinkproc(Proc *p)
 }
 
 void
-_schedinit(void *arg)
+_schedinit(void)
 {
 	Proc *p;
 	Thread *t, **l;
 
-	p = arg;
+	p = _threadgetproc();
 	p->pid = getpid();
-	_threadsetproc(p);
 	while(setjmp(p->sched))
 		;
 	_threaddebug(DBGSCHED, "top of schedinit, _threadexitsallstatus=%p", _threadexitsallstatus);
@@ -164,7 +163,7 @@ Resched:
 		_threaddebug(DBGSCHED, "running %d.%d", t->proc->pid, t->id);
 		p->thread = t;
 		if(t->moribund){
-			_threaddebug(DBGSCHED, "%d.%d marked to die");
+			_threaddebug(DBGSCHED, "%d.%d marked to die", t->proc->pid, t->id);
 			goto Resched;
 		}
 		t->state = Running;
diff --git a/sys/src/libthread/threadimpl.h b/sys/src/libthread/threadimpl.h
index 6574a6201..b5006f914 100644
--- a/sys/src/libthread/threadimpl.h
+++ b/sys/src/libthread/threadimpl.h
@@ -157,15 +157,12 @@ int	_schedexec(Execargs*);
 void	_schedexecwait(void);
 void	_schedexit(Proc*);
 int	_schedfork(Proc*);
-void	_schedinit(void*);
-void	_systhreadinit(void);
+void	_schedinit(void);
 void	_threadassert(char*);
 void	_threadbreakrendez(void);
-void	_threaddebug(ulong, char*, ...);
+void	_threadprint(char*, ...);
 void	_threadexitsall(char*);
 void	_threadflagrendez(Thread*);
-Proc*	_threadgetproc(void);
-void	_threadsetproc(Proc*);
 void	_threadinitstack(Thread*, void(*)(void*), void*);
 void*	_threadmalloc(long, int);
 void	_threadnote(void*, char*);
@@ -173,6 +170,10 @@ void	_threadready(Thread*);
 void*	_threadrendezvous(void*, void*);
 void	_threadsysfatal(char*, va_list);
 
+Proc	**_threadprocp;
+#define	_threadgetproc()	(*_threadprocp)
+#define	_threadsetproc(p)	(*_threadprocp = (p))
+
 extern int			_threaddebuglevel;
 extern char*		_threadexitsallstatus;
 extern Pqueue		_threadpq;
@@ -187,4 +188,7 @@ extern Rgrp		_threadrgrp;
 #define DBGNOTE	(1 << 20)
 #define DBGEXEC	(1 << 21)
 
+#pragma	varargck argpos _threadprint 1
+#define	_threaddebug(flag, ...)	if((_threaddebuglevel&(flag))==0){}else _threadprint(__VA_ARGS__)
+
 #define ioproc_arg(io, type)	(va_arg((io)->arg, type))