Messages in this thread | | | From | (Eric W. Biederman) | Date | Mon, 04 Aug 2008 11:51:33 -0700 | Subject | Re: [PATCH 21/25] serial: change remove NR_IRQS in 8250.c v2 |
| |
Alan Cox <alan@lxorguk.ukuu.org.uk> writes:
>> Looks like we can also tweak serial_do_unlink to free irq_info when >> the list goes empty, so we don't have a leak if the driver is ever >> unloaded. > > Like this (again not yet tested) > > 8250: Remove NR_IRQ usage > > From: Alan Cox <alan@redhat.com>
I think we've just about got it.
> /* > * Here we define the default xmit fifo size used for each type of UART. > @@ -1541,9 +1545,32 @@ static void serial_do_unlink(struct irq_info *i, struct > uart_8250_port *up) > > static int serial_link_irq_chain(struct uart_8250_port *up) > { > - struct irq_info *i = irq_lists + up->port.irq; > + struct hlist_head *h; > + struct hlist_node *n; > + struct irq_info *i; > int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0; > > + mutex_lock(&hash_mutex); > + > + h = &irq_lists[up->port.irq % NR_IRQ_HASH]; > + > + hlist_for_each(n, h) { > + i = hlist_entry(n, struct irq_info, node); > + if (i->irq == up->port.irq) > + break; > + } > + > + if (n == NULL) { > + i = kzalloc(sizeof(struct irq_info), GFP_KERNEL); > + if (i == NULL) { > + mutex_unlock(&hash_mutex); > + return -ENOMEM; > + } > + spin_lock_init(&i->lock); > + hlist_add_head(&i->node, h); > + } > + mutex_unlock(&hash_mutex); > + > spin_lock_irq(&i->lock); > > if (i->head) {
Note there is also an error path that calls serial_do_unlink in serial_link_irq_chain. That we might want to free the entry in. Do we want move hash table entry freeing into serial_do_unlink or duplicate it here?
Eric
| |