- bump __FreeBSD version to reflect added buf_ring, memory barriers,

  and ifnet functions

- add memory barriers to <machine/atomic.h>
- update drivers to only conditionally define their own

- add lockless producer / consumer ring buffer
- remove ring buffer implementation from cxgb and update its callers

- add if_transmit(struct ifnet *ifp, struct mbuf *m) to ifnet to
  allow drivers to efficiently manage multiple hardware queues
  (i.e. not serialize all packets through one ifq)
- expose if_qflush to allow drivers to flush any driver managed queues

This work was supported by Bitgravity Inc. and Chelsio Inc.

1 files changed, 4 insertions, 0 deletions

diff --git a/sys/dev/mxge/if_mxge_var.h b/sys/dev/mxge/if_mxge_var.h
index 21127862dc74..e57c637f300b 100644
--- a/sys/dev/mxge/if_mxge_var.h
+++ b/sys/dev/mxge/if_mxge_var.h
@@ -279,6 +279,8 @@ struct mxge_media_type
 /* implement our own memory barriers, since bus_space_barrier
    cannot handle write-combining regions */
 
+#if __FreeBSD_version < 800053
+
 #if defined (__GNUC__)
   #if #cpu(i386) || defined __i386 || defined i386 || defined __i386__ || #cpu(x86_64) || defined __x86_64__
     #define mb()  __asm__ __volatile__ ("sfence;": : :"memory")
@@ -293,6 +295,8 @@ struct mxge_media_type
   #error "unknown compiler"
 #endif
 
+#endif
+
 static inline void
 mxge_pio_copy(volatile void *to_v, void *from_v, size_t size)
 {