On Thu, Nov 29, 2012 at 11:55:43AM +0000, David Woodhouse wrote:
> On Thu, 2012-11-29 at 11:57 +0100, Krzysztof Mazur wrote:
> > do we really need to wait here?
> > Why don't just do something like that:
> >
> > tasklet_disable(&card->tlet);
> > spin_lock(&card->tx_queue_lock);
> > for each skb in queue
> > SKB_CB(skb)->vcc = NULL;
> > spin_unlock(&card->tx_queue_lock);
> > tasklet_enable(&card->tlet);
> >
> > or if we really want to call vcc->pop() for such skbs:
> >
> > tasklet_disable(&card->tlet);
> > spin_lock(&card->tx_queue_lock);
> > for each skb in queue {
> > skb_get(skb);
> > solos_pop(SKB_CB(skb)->vcc, skb);
> > SKB_CB(skb)->vcc = NULL;
> > }
> > spin_unlock(&card->tx_queue_lock);
> > tasklet_enable(&card->tlet);
>
> Yes, we could certainly remove the packets from the tx_queue first.
>
> However, in the card->using_dma case there might be a skb for this vcc
> *currently* being DMA'd, and we'd still need to wait for that one.
Removing packets from tx_queue is not needed. We can transmit packets
also after close. We just can't call vcc->pop() after close,
so we can just set SKB_CB(skb)->vcc of such packets to NULL so fpga_tx()
won't call vcc->pop().
Maybe I was not precise enough, I'm think that all we need is
something like that:
-- >8 --
Subject: [PATCH] solos-pci: don't call vcc->pop() after pclose()
After atmdev_ops->close() we cannot use vcc->pop() because the vcc may,
and probably will be destroyed.
We can just set vcc for such frames to NULL because fpga_tx() after
completion will call dev_kfree_skb() in that case.
Signed-off-by: Krzysztof Mazur <krzys...@podlesie.net>
---
drivers/atm/solos-pci.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/atm/solos-pci.c b/drivers/atm/solos-pci.c
index 9851093..aabe021 100644
--- a/drivers/atm/solos-pci.c
+++ b/drivers/atm/solos-pci.c
@@ -868,6 +868,19 @@ static void pclose(struct atm_vcc *vcc)
struct solos_card *card = vcc->dev->dev_data;
struct sk_buff *skb;
struct pkt_hdr *header;
+ unsigned int port;
+
+ tasklet_disable(&card->tlet);
+ spin_lock(&card->tx_queue_lock);
+ for (port = 0; port < card->nr_ports; port++)
+ skb_queue_walk(&card->tx_queue[port], skb)
+ if (SKB_CB(skb)->vcc == vcc) {
+ skb_get(skb);
+ solos_pop(SKB_CB(skb)->vcc, skb);
+ SKB_CB(skb)->vcc = NULL;
+ }
+ spin_unlock(&card->tx_queue_lock);
+ tasklet_enable(&card->tlet);
skb = alloc_skb(sizeof(*header), GFP_ATOMIC);
if (!skb) {
--
1.8.0.411.g71a7da8
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