Message ID | 49C36AE5.6040807@cosmosbay.com |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: Eric Dumazet <dada1@cosmosbay.com> Date: Fri, 20 Mar 2009 11:07:33 +0100 > So first patch is OK, what about this updated Changelog ? > > [PATCH] net: remove useless prefetch() call > > There is no gain using prefetch() in dev_hard_start_xmit(), since > we already had to read ops->ndo_select_queue pointer in dev_pick_tx(), > and both pointers are probably located in the same cache line. > > This prefetch call slows down fast path because of a stall in address > computation. Applied, thanks. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/dev.c b/net/core/dev.c index c013031..c97e27d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1670,7 +1670,6 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, const struct net_device_ops *ops = dev->netdev_ops; int rc; - prefetch(&dev->netdev_ops->ndo_start_xmit); if (likely(!skb->next)) { if (!list_empty(&ptype_all)) dev_queue_xmit_nit(skb, dev);