Re: [PATCH 1/2] net: add IFF_SKB_TX_SHARED flag to priv_flags

Neil Horman
2011-07-26T14:54:32Z

On Mon, Jul 25, 2011 at 10:11:22PM +0200, Eric Dumazet wrote:
> Le lundi 25 juillet 2011 à 15:45 -0400, Neil Horman a écrit :
> > Pktgen attempts to transmit shared skbs to net devices, which can't be used by
> > some drivers as they keep state information in skbs. This patch adds a flag
> > marking drivers as being able to handle shared skbs in their tx path. Drivers
> > are defaulted to being unable to do so, but calling ether_setup enables this
> > flag, as 90% of the drivers calling ether_setup touch real hardware and can
> > handle shared skbs. A subsequent patch will audit drivers to ensure that the
> > flag is set properly
> >
> > Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
> > Reported-by: Jiri Pirko <jpirko@redhat.com>
> > CC: Robert Olsson <robert.olsson@its.uu.se>
> > CC: Eric Dumazet <eric.dumazet@gmail.com>
> > CC: Alexey Dobriyan <adobriyan@gmail.com>
> > CC: David S. Miller <davem@davemloft.net>
> > ---
> > include/linux/if.h | 2 ++
> > net/core/pktgen.c | 8 +++++---
> > net/ethernet/eth.c | 1 +
> > 3 files changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/include/linux/if.h b/include/linux/if.h
> > index 3bc63e6..03489ca 100644
> > --- a/include/linux/if.h
> > +++ b/include/linux/if.h
> > @@ -76,6 +76,8 @@
> > #define IFF_BRIDGE_PORT 0x4000 /* device used as bridge port */
> > #define IFF_OVS_DATAPATH 0x8000 /* device used as Open vSwitch
> > * datapath port */
> > +#define IFF_TX_SKB_SHARING 0x10000 /* The interface supports sharing
> > + * skbs on transmit */
> >
> > #define IF_GET_IFACE 0x0001 /* for querying only */
> > #define IF_GET_PROTO 0x0002
> > diff --git a/net/core/pktgen.c b/net/core/pktgen.c
> > index f76079c..53f3f15 100644
> > --- a/net/core/pktgen.c
> > +++ b/net/core/pktgen.c
> > @@ -1070,7 +1070,9 @@ static ssize_t pktgen_if_write(struct file *file,
> > len = num_arg(&user_buffer[i], 10, &value);
> > if (len < 0)
> > return len;
> > -
> > + if ((len > 0) &&
>
> if ((value > 0) ...
>
Thank you Eric, I'll respin this shortly
Neil