示例#1
0
文件: taslock.c 项目: Requaos/harvey
void
ilock(Lock *l)
{
	Proc *up = externup();
	Mpl pl;
	uintptr_t pc;
	uint64_t t0;

	pc = getcallerpc();
	lockstats.locks++;

	pl = splhi();
	if(TAS(&l->key) != 0){
		cycles(&t0);
		lockstats.glare++;
		/*
		 * Cannot also check l->pc, l->m, or l->isilock here
		 * because they might just not be set yet, or
		 * (for pc and m) the lock might have just been unlocked.
		 */
		for(;;){
			lockstats.inglare++;
			splx(pl);
			while(l->key)
				;
			pl = splhi();
			if(TAS(&l->key) == 0){
				if(l != &waitstatslk)
					addwaitstat(pc, t0, WSlock);
				goto acquire;
			}
		}
	}
acquire:
	machp()->ilockdepth++;
	if(up)
		up->lastilock = l;
	l->pl = pl;
	l->_pc = pc;
	l->p = up;
	l->isilock = 1;
	l->m = machp();
	if(LOCKCYCLES)
		cycles(&l->lockcycles);
}
示例#2
0
文件: taslock.c 项目: Requaos/harvey
int
lock(Lock *l)
{
	Proc *up = externup();
	int i;
	uintptr_t pc;
	uint64_t t0;

	pc = getcallerpc();

	lockstats.locks++;
	if(up)
		ainc(&up->nlocks);	/* prevent being scheded */
	if(TAS(&l->key) == 0){
		if(up)
			up->lastlock = l;
		l->_pc = pc;
		l->p = up;
		l->isilock = 0;
		if(LOCKCYCLES)
			cycles(&l->lockcycles);

		return 0;
	}
	if(up)
		adec(&up->nlocks);

	cycles(&t0);
	lockstats.glare++;
	for(;;){
		lockstats.inglare++;
		i = 0;
		while(l->key){
			if(sys->nmach < 2 && up && up->edf && (up->edf->flags & Admitted)){
				/*
				 * Priority inversion, yield on a uniprocessor; on a
				 * multiprocessor, the other processor will unlock
				 */
				print("inversion %#p pc %#p proc %d held by pc %#p proc %d\n",
					l, pc, up ? up->pid : 0, l->_pc, l->p ? l->p->pid : 0);
				up->edf->d = todget(nil);	/* yield to process with lock */
			}
			if(i++ > 100000000){
				i = 0;
				lockloop(l, pc);
			}
		}
		if(up)
			ainc(&up->nlocks);
		if(TAS(&l->key) == 0){
			if(up)
				up->lastlock = l;
			l->_pc = pc;
			l->p = up;
			l->isilock = 0;
			if(LOCKCYCLES)
				cycles(&l->lockcycles);
			if(l != &waitstatslk)
				addwaitstat(pc, t0, WSlock);
			return 1;
		}
		if(up)
			adec(&up->nlocks);
	}
}
示例#3
0
文件: qlock.c 项目: qioixiy/harvey
static void
slockstat(uintptr_t pc, uint64_t w)
{
	addwaitstat(pc, w, WSslock);
}