Exemple #1
0
/*
 *  Send or receive packet.
 */
static int sock_xmit(struct socket *sock, int send, void *buf, int size,
		int msg_flags)
{
	int result;
	struct msghdr msg;
	struct kvec iov;
	sigset_t blocked, oldset;

	/* Allow interception of SIGKILL only
	 * Don't allow other signals to interrupt the transmission */
	siginitsetinv(&blocked, sigmask(SIGKILL));
	sigprocmask(SIG_SETMASK, &blocked, &oldset);

	do {
		sock->sk->sk_allocation = GFP_NOIO;
		iov.iov_base = buf;
		iov.iov_len = size;
		msg.msg_name = NULL;
		msg.msg_namelen = 0;
		msg.msg_control = NULL;
		msg.msg_controllen = 0;
		msg.msg_flags = msg_flags | MSG_NOSIGNAL;

		if (send)
			result = kernel_sendmsg(sock, &msg, &iov, 1, size);
		else
			result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0);

		if (signal_pending(current)) {
			siginfo_t info;
			printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n",
				current->pid, current->comm,
				dequeue_signal_lock(current, &current->blocked, &info));
			result = -EINTR;
			break;
		}

		if (result <= 0) {
			if (result == 0)
				result = -EPIPE; /* short read */
			break;
		}
		size -= result;
		buf += result;
	} while (size > 0);

	sigprocmask(SIG_SETMASK, &oldset, NULL);

	return result;
}
static int htckovsky_oj_thread(void *v) {
	struct completion exit;
	siginfo_t info;

	daemonize("oj_thread");
	allow_signal(SIGKILL);
	init_completion(&exit);

	while (true) {
		if (signal_pending(current)) {
			if (dequeue_signal_lock(current, &current->blocked, &info)
				== SIGKILL) {
				goto done;
			}
		}
		htckovsky_oj_work(NULL);
		msleep(OJ_POLL_DELAY);
	}

done:
	complete_and_exit(&exit, 0);
}
/*
 *  Send or receive packet.
 */
static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size,
		int msg_flags)
{
	struct socket *sock = nbd->sock;
	int result;
	struct msghdr msg;
	struct kvec iov;
	sigset_t blocked, oldset;

	if (unlikely(!sock)) {
		dev_err(disk_to_dev(nbd->disk),
			"Attempted %s on closed socket in sock_xmit\n",
			(send ? "send" : "recv"));
		return -EINVAL;
	}

	/* Allow interception of SIGKILL only
	 * Don't allow other signals to interrupt the transmission */
	siginitsetinv(&blocked, sigmask(SIGKILL));
	sigprocmask(SIG_SETMASK, &blocked, &oldset);

	do {
		sock->sk->sk_allocation = GFP_NOIO;
		iov.iov_base = buf;
		iov.iov_len = size;
		msg.msg_name = NULL;
		msg.msg_namelen = 0;
		msg.msg_control = NULL;
		msg.msg_controllen = 0;
		msg.msg_flags = msg_flags | MSG_NOSIGNAL;

		if (send) {
			struct timer_list ti;

			if (nbd->xmit_timeout) {
				init_timer(&ti);
				ti.function = nbd_xmit_timeout;
				ti.data = (unsigned long)current;
				ti.expires = jiffies + nbd->xmit_timeout;
				add_timer(&ti);
			}
			result = kernel_sendmsg(sock, &msg, &iov, 1, size);
			if (nbd->xmit_timeout)
				del_timer_sync(&ti);
		} else
			result = kernel_recvmsg(sock, &msg, &iov, 1, size,
						msg.msg_flags);

		if (signal_pending(current)) {
			siginfo_t info;
			printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n",
				task_pid_nr(current), current->comm,
				dequeue_signal_lock(current, &current->blocked, &info));
			result = -EINTR;
			sock_shutdown(nbd, !send);
			break;
		}

		if (result <= 0) {
			if (result == 0)
				result = -EPIPE; /* short read */
			break;
		}
		size -= result;
		buf += result;
	} while (size > 0);

	sigprocmask(SIG_SETMASK, &oldset, NULL);

	return result;
}
Exemple #4
0
static int jffs2_garbage_collect_thread(void *_c)
{
	struct jffs2_sb_info *c = _c;

	daemonize("jffs2_gcd_mtd%d", c->mtd->index);
	allow_signal(SIGKILL);
	allow_signal(SIGSTOP);
	allow_signal(SIGCONT);

	c->gc_task = current;
	complete(&c->gc_thread_start);

	set_user_nice(current, 10);

	for (;;) {
		allow_signal(SIGHUP);

		if (!jffs2_thread_should_wake(c)) {
			set_current_state (TASK_INTERRUPTIBLE);
			D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread sleeping...\n"));
			/* Yes, there's a race here; we checked jffs2_thread_should_wake()
			   before setting current->state to TASK_INTERRUPTIBLE. But it doesn't
			   matter - We don't care if we miss a wakeup, because the GC thread
			   is only an optimisation anyway. */
			schedule();
		}

		if (try_to_freeze())
			continue;

		cond_resched();

		/* Put_super will send a SIGKILL and then wait on the sem.
		 */
		while (signal_pending(current)) {
			siginfo_t info;
			unsigned long signr;

			signr = dequeue_signal_lock(current, &current->blocked, &info);

			switch(signr) {
			case SIGSTOP:
				D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): SIGSTOP received.\n"));
				set_current_state(TASK_STOPPED);
				schedule();
				break;

			case SIGKILL:
				D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): SIGKILL received.\n"));
				goto die;

			case SIGHUP:
				D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): SIGHUP received.\n"));
				break;
			default:
				D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): signal %ld received\n", signr));
			}
		}
		/* We don't want SIGHUP to interrupt us. STOP and KILL are OK though. */
		disallow_signal(SIGHUP);

		D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): pass\n"));
		if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
			printk(KERN_NOTICE "No space for garbage collection. Aborting GC thread\n");
			goto die;
		}
	}
 die:
	spin_lock(&c->erase_completion_lock);
	c->gc_task = NULL;
	spin_unlock(&c->erase_completion_lock);
	complete_and_exit(&c->gc_thread_exit, 0);
}
static int jffs2_garbage_collect_thread(void *_c)
{
	struct jffs2_sb_info *c = _c;

	allow_signal(SIGKILL);
	allow_signal(SIGSTOP);
	allow_signal(SIGCONT);

	c->gc_task = current;
	complete(&c->gc_thread_start);

	set_user_nice(current, 10);

	set_freezable();
	for (;;) {
		allow_signal(SIGHUP);
	again:
		spin_lock(&c->erase_completion_lock);
		if (!jffs2_thread_should_wake(c)) {
			set_current_state (TASK_INTERRUPTIBLE);
			spin_unlock(&c->erase_completion_lock);
			jffs2_dbg(1, "%s(): sleeping...\n", __func__);
			schedule();
		} else
			spin_unlock(&c->erase_completion_lock);
			

		/* Problem - immediately after bootup, the GCD spends a lot
		 * of time in places like jffs2_kill_fragtree(); so much so
		 * that userspace processes (like gdm and X) are starved
		 * despite plenty of cond_resched()s and renicing.  Yield()
		 * doesn't help, either (presumably because userspace and GCD
		 * are generally competing for a higher latency resource -
		 * disk).
		 * This forces the GCD to slow the hell down.   Pulling an
		 * inode in with read_inode() is much preferable to having
		 * the GC thread get there first. */
		schedule_timeout_interruptible(msecs_to_jiffies(50));

		if (kthread_should_stop()) {
			jffs2_dbg(1, "%s(): kthread_stop() called\n", __func__);
			goto die;
		}

		/* Put_super will send a SIGKILL and then wait on the sem.
		 */
		while (signal_pending(current) || freezing(current)) {
			siginfo_t info;
			unsigned long signr;

			if (try_to_freeze())
				goto again;

			signr = dequeue_signal_lock(current, &current->blocked, &info);

			switch(signr) {
			case SIGSTOP:
				jffs2_dbg(1, "%s(): SIGSTOP received\n",
					  __func__);
				set_current_state(TASK_STOPPED);
				schedule();
				break;

			case SIGKILL:
				jffs2_dbg(1, "%s(): SIGKILL received\n",
					  __func__);
				goto die;

			case SIGHUP:
				jffs2_dbg(1, "%s(): SIGHUP received\n",
					  __func__);
				break;
			default:
				jffs2_dbg(1, "%s(): signal %ld received\n",
					  __func__, signr);
			}
		}
		/* We don't want SIGHUP to interrupt us. STOP and KILL are OK though. */
		disallow_signal(SIGHUP);

		jffs2_dbg(1, "%s(): pass\n", __func__);
		if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
			pr_notice("No space for garbage collection. Aborting GC thread\n");
			goto die;
		}
	}
 die:
	spin_lock(&c->erase_completion_lock);
	c->gc_task = NULL;
	spin_unlock(&c->erase_completion_lock);
	complete_and_exit(&c->gc_thread_exit, 0);
}
static int jffs2_garbage_collect_thread(void *_c)
{
	struct jffs2_sb_info *c = _c;

	allow_signal(SIGKILL);
	allow_signal(SIGSTOP);
	allow_signal(SIGCONT);

	c->gc_task = current;
	complete(&c->gc_thread_start);

	set_user_nice(current, 10);

	set_freezable();
	for (;;) {
		allow_signal(SIGHUP);
	again:
		spin_lock(&c->erase_completion_lock);
		if (!jffs2_thread_should_wake(c)) {
			set_current_state (TASK_INTERRUPTIBLE);
			spin_unlock(&c->erase_completion_lock);
			jffs2_dbg(1, "%s(): sleeping...\n", __func__);
			schedule();
		} else
			spin_unlock(&c->erase_completion_lock);
			

		schedule_timeout_interruptible(msecs_to_jiffies(50));

		if (kthread_should_stop()) {
			jffs2_dbg(1, "%s(): kthread_stop() called\n", __func__);
			goto die;
		}

		while (signal_pending(current) || freezing(current)) {
			siginfo_t info;
			unsigned long signr;

			if (try_to_freeze())
				goto again;

			signr = dequeue_signal_lock(current, &current->blocked, &info);

			switch(signr) {
			case SIGSTOP:
				jffs2_dbg(1, "%s(): SIGSTOP received\n",
					  __func__);
				set_current_state(TASK_STOPPED);
				schedule();
				break;

			case SIGKILL:
				jffs2_dbg(1, "%s(): SIGKILL received\n",
					  __func__);
				goto die;

			case SIGHUP:
				jffs2_dbg(1, "%s(): SIGHUP received\n",
					  __func__);
				break;
			default:
				jffs2_dbg(1, "%s(): signal %ld received\n",
					  __func__, signr);
			}
		}
		
		disallow_signal(SIGHUP);

		jffs2_dbg(1, "%s(): pass\n", __func__);
		if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
			pr_notice("No space for garbage collection. Aborting GC thread\n");
			goto die;
		}
	}
 die:
	spin_lock(&c->erase_completion_lock);
	c->gc_task = NULL;
	spin_unlock(&c->erase_completion_lock);
	complete_and_exit(&c->gc_thread_exit, 0);
}