Sorry! forgot to CC Michael, doing now.
> 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 <pagu...@redhat.com> > Reviewed-by: Michael S. Tsirkin <m...@redhat.com> > Reviewed-by: David Gibson <dgib...@redhat.com> > --- > net/core/dev.c | 19 +++++++++++++------ > 1 file changed, 13 insertions(+), 6 deletions(-) > > diff --git a/net/core/dev.c b/net/core/dev.c > index e916ba8..abe9560 100644 > --- a/net/core/dev.c > +++ b/net/core/dev.c > @@ -6059,17 +6059,25 @@ 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); > > BUG_ON(count < 1); > > - rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL); > - if (!rx) > - return -ENOMEM; > - > + rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); > + if (!rx) { > + rx = vzalloc(sz); > + if (!rx) > + return -ENOMEM; > + } > dev->_rx = rx; > > for (i = 0; i < count; i++) > @@ -6698,9 +6706,8 @@ void free_netdev(struct net_device *dev) > > netif_free_tx_queues(dev); > #ifdef CONFIG_SYSFS > - kfree(dev->_rx); > + netif_free_rx_queues(dev); > #endif > - > kfree(rcu_dereference_protected(dev->ingress_queue, 1)); > > /* Flush device addresses */ > -- > 1.8.3.1 > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/