Messages in this thread | | | Date | Mon, 18 Aug 2014 21:43:40 +0400 | From | Sergei Shtylyov <> | Subject | Re: [RFC 1/4] net: allow large number of rx queues |
| |
Hello.
On 08/18/2014 05:37 PM, Pankaj Gupta wrote:
> netif_alloc_rx_queues() uses kcalloc() to allocate memory > for "struct netdev_queue *_rx" array. > If we are doing large rx queue allocation kcalloc() might > fail, so this patch does a fallback to vzalloc(). > Similar implementation is done for tx queue allocation in > netif_alloc_netdev_queues().
> We avoid failure of high order memory allocation > with the help of vzalloc(), this allows us to do large > rx and tx queue allocation which in turn helps us to > increase the number of queues in tun.
> As vmalloc() adds overhead on a critical network path, > __GFP_REPEAT flag is used with kzalloc() to do this fallback > only when really needed.
> Signed-off-by: Pankaj Gupta <pagupta@redhat.com> > Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > Reviewed-by: David Gibson <dgibson@redhat.com> > --- > net/core/dev.c | 20 +++++++++++++------- > 1 file changed, 13 insertions(+), 7 deletions(-)
> diff --git a/net/core/dev.c b/net/core/dev.c > index 1c15b18..a455a02 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -5942,17 +5942,24 @@ void netif_stacked_transfer_operstate(const struct net_device *rootdev, > EXPORT_SYMBOL(netif_stacked_transfer_operstate); > > #ifdef CONFIG_SYSFS > +static void netif_free_rx_queues(struct net_device *dev) > +{ > + kvfree(dev->_rx); > +} > + > static int netif_alloc_rx_queues(struct net_device *dev) > { > unsigned int i, count = dev->num_rx_queues; > struct netdev_rx_queue *rx; > - > + size_t sz = count * sizeof(*rx);
Please keep an empty line after declarations.
> BUG_ON(count < 1); >
WBR, Sergei
| |