A bunch of netmap fixes:

USERSPACE:
1. add support for devices with different number of rx and tx queues;

2. add better support for zero-copy operation, adding an extra field
   to the netmap ring to indicate how many buffers we have already processed
   but not yet released (with help from Eddie Kohler);

3. The two changes above unfortunately require an API change, so while
   at it add a version field and some spares to the ioctl() argument
   to help detect mismatches.

4. update the manual page for the two changes above;

5. update sample applications in tools/tools/netmap

KERNEL:

1. simplify the internal structures moving the global wait queues
   to the 'struct netmap_adapter';

2. simplify the functions that map kring<->nic ring indexes

3. normalize device-specific code, helps mainteinance;

4. start exploring the impact of micro-optimizations (prefetch etc.)
   in the ixgbe driver.
   Use 'legacy' descriptors on the tx ring and prefetch slots gives
   about 20% speedup at 900 MHz. Another 7-10% would come from removing
   the explict calls to bus_dmamap* in the core (they are effectively
   NOPs in this case, but it takes expensive load of the per-buffer
   dma maps to figure out that they are all NULL.

   Rx performance not investigated.

I am postponing the MFC so i can import a few more improvements
before merging.

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/dev/re/if_re.c b/sys/dev/re/if_re.c
index f73389e..d11661c 100644
--- a/sys/dev/re/if_re.c
+++ b/sys/dev/re/if_re.c
@@ -2111,6 +2111,7 @@ re_rxeof(struct rl_softc *sc, int *rx_npktsp)
 	ifp = sc->rl_ifp;
 #ifdef DEV_NETMAP
 	if (ifp->if_capenable & IFCAP_NETMAP) {
+		NA(ifp)->rx_rings->nr_kflags |= NKR_PENDINTR;
 		selwakeuppri(&NA(ifp)->rx_rings->si, PI_NET);
 		return 0;
 	}