[ovs-dev] [PATCH 2/2] datapath: Move Netlink PID for userspace actions from flows to actions.

[Ben Pfaff]

On Tue, Oct 04, 2011 at 02:40:27PM -0700, Ben Pfaff wrote:
> On Tue, Oct 04, 2011 at 01:22:39PM -0700, Ben Pfaff wrote:
> > Commit b063d9f06 "datapath: Use unicast Netlink sockets for upcalls" that
> > switched from multicast to unicast Netlink for sending upcalls added a
> > Netlink PID to each kernel flow, used by OVS_ACTION_ATTR_USERSPACE actions
> > within the flow as target.
> > 
> > This commit drops this per-flow PID in favor of a per-action PID, because
> > that is more flexible.  It does not yet make use of this additional
> > flexibility, so behavior should not change.
> > 
> > Signed-off-by: Ben Pfaff <blp at nicira.com>
> > Bug #7559.
> 
> Oops, this forgot to update the OVS_ACTION_ATTR_USERSPACE parser in
> dpif-netdev.  I'll follow up with a fix when I have one.

When I went to do this, I discovered that the "sample" action wasn't
implemented in userspace and that there were other shortcomings in
dpif-netdev.  The revised series I'll send out soon therefore contains
the following related commits:

netlink: New macros NL_NESTED_FOR_EACH, NL_NESTED_FOR_EACH_UNSAFE.
dpif-netdev: Simplify code by removing dpif_netdev_validate_actions().
dpif-netdev: Implement OVS_ACTION_ATTR_SAMPLE action.

This patch only really changes in dpif-netdev.c, so in case you've
already read most of this patch that's all you really need to re-review.