Evgeniy Polyakov wrote:
Hi Steve.
On Sun, Sep 23, 2007 at 11:12:12AM -0500, Steve Wise ([EMAIL PROTECTED]) wrote:
The pktgen module provides a way to "clone" the skb its using for
transmission, and allows passing N clones of the originally created skb
to the driver under test. However, it doesn't really use skb_clone(),
but rather it just bumps the skb->users count for each "clone" and
passes the same skb ptr to the driver.
Q: Is that a valid use of skb->users or should pktgen really be cloning
the skbuff?
It's a hack, but since skb is owned by pktgen only (no copies in some
outside queues or some other access) it is allowed just to bump reference
counter (i.e. 'share' skb in usual notation).
Its a hack that breaks cxgb3 because cxgb3 uses the skb->cb area for
each skb passed down. So cxgb3 is at fault then? IE a driver cannot
use the skb->cb field if the users count is > 1? Or maybe a driver can
_never_ use the cb field?
Steve.
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
