plan 9 kernel history: overview | file list | diff list

1995/0110/port/taslock.c (diff list | history)

1995/0109/sys/src/9/port/taslock.c:8,401995/0110/sys/src/9/port/taslock.c:8,42 (short | long | prev | next)
1992/0222    
void 
lock(Lock *l) 
{ 
1995/0108    
	int n; 
1995/0110    
	if(tas(&l->key) == 0) 
		return; 
1995/0108    
 
	if(up) { 
		n = up->inlock+2; 
		up->inlock = n; 
1995/0110    
	for(;;){ 
		while(l->key) 
			; 
1995/0108    
		if(tas(&l->key) == 0) 
			return; 
                 
		for(;;){ 
			while(l->key) 
				if(conf.nproc == 1) { 
					up->yield = 1; 
					sched(); 
				} 
			up->inlock = n; 
			if(tas(&l->key) == 0) 
				return; 
		} 
	} 
1995/0110    
} 
1995/0108    
 
1993/1204    
	if(tas(&l->key) == 0) 
1995/0110    
void 
ilock(Lock *l) 
{ 
	ulong x; 
 
	x = splhi(); 
	if(tas(&l->key) == 0){ 
		l->sr = x; 
1993/1204    
		return; 
1995/0110    
	} 
 
1993/0830    
	for(;;){ 
1994/0808    
		while(l->key) 
			; 
1993/0830    
		if(tas(&l->key) == 0) 
1995/0110    
		if(tas(&l->key) == 0){ 
			l->sr = x; 
1992/0222    
			return; 
1995/0110    
		} 
1992/0222    
	} 
} 
 
1995/0109/sys/src/9/port/taslock.c:41,601995/0110/sys/src/9/port/taslock.c:43,51
1995/0109    
int 
canlock(Lock *l) 
1994/0322    
{ 
1995/0109    
	int n; 
1994/0323    
                 
1995/0109    
	if(up) { 
		n = up->inlock; 
		up->inlock = n+2; 
		if(tas(&l->key)) { 
			up->inlock = n; 
			return 0; 
1994/0323    
		} 
1995/0109    
		return 1; 
1994/0322    
	} 
                 
1992/0222    
	if(tas(&l->key)) 
		return 0; 
1995/0110    
 
1992/0222    
	return 1; 
} 
 
1995/0109/sys/src/9/port/taslock.c:61,931995/0110/sys/src/9/port/taslock.c:52,66
1992/0222    
void 
unlock(Lock *l) 
{ 
1995/0108    
	int n; 
                 
	if(up) { 
		n = up->inlock-2; 
		if(n < 0) 
			n = 0; 
		up->inlock = n; 
	} 
1995/0109    
	l->key = 0; 
1994/0322    
} 
 
void 
1995/0109    
ilock(Lock *l) 
{ 
	ulong sr; 
                 
	sr = splhi(); 
	lock(l); 
	l->sr = sr; 
} 
                 
void 
1994/0322    
iunlock(Lock *l) 
{ 
	ulong sr; 
 
	sr = l->sr; 
1995/0109    
	unlock(l); 
1995/0110    
	l->key = 0; 
1994/0322    
	splx(sr); 
1992/0222    
} 


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