static int mon_text_release(struct inode *inode, struct file *file)
{
	struct mon_reader_text *rp = file->private_data;
	struct mon_bus *mbus;
	/* unsigned long flags; */
	struct list_head *p;
	struct mon_event_text *ep;

	mutex_lock(&mon_lock);
	mbus = inode->i_private;

	if (mbus->nreaders <= 0) {
		printk(KERN_ERR TAG ": consistency error on close\n");
		mutex_unlock(&mon_lock);
		return 0;
	}
	mon_reader_del(mbus, &rp->r);

	/*
	 * In theory, e_list is protected by mbus->lock. However,
	 * after mon_reader_del has finished, the following is the case:
	 *  - we are not on reader list anymore, so new events won't be added;
	 *  - whole mbus may be dropped if it was orphaned.
	 * So, we better not touch mbus.
	 */
	/* spin_lock_irqsave(&mbus->lock, flags); */
	while (!list_empty(&rp->e_list)) {
		p = rp->e_list.next;
		ep = list_entry(p, struct mon_event_text, e_link);
		list_del(p);
		--rp->nevents;
		kmem_cache_free(rp->e_slab, ep);
	}
	/* spin_unlock_irqrestore(&mbus->lock, flags); */

	kmem_cache_destroy(rp->e_slab);
	kfree(rp->printf_buf);
	kfree(rp);

	mutex_unlock(&mon_lock);
	return 0;
}
Esempio n. 2
0
static int mon_text_release(struct inode *inode, struct file *file)
{
	struct mon_reader_text *rp = file->private_data;
	struct mon_bus *mbus;
	/*                      */
	struct list_head *p;
	struct mon_event_text *ep;

	mutex_lock(&mon_lock);
	mbus = inode->i_private;

	if (mbus->nreaders <= 0) {
		printk(KERN_ERR TAG ": consistency error on close\n");
		mutex_unlock(&mon_lock);
		return 0;
	}
	mon_reader_del(mbus, &rp->r);

	/*
                                                          
                                                                 
                                                                       
                                                    
                                 
  */
	/*                                        */
	while (!list_empty(&rp->e_list)) {
		p = rp->e_list.next;
		ep = list_entry(p, struct mon_event_text, e_link);
		list_del(p);
		--rp->nevents;
		kmem_cache_free(rp->e_slab, ep);
	}
	/*                                             */

	kmem_cache_destroy(rp->e_slab);
	kfree(rp->printf_buf);
	kfree(rp);

	mutex_unlock(&mon_lock);
	return 0;
}