Get rid if em_align. This approach used to make sense, but now that the

hardware rx mtu always gets set to the maximum supported value we will hit
it for every received packet.  Instead, use a larger mbuf cluster size on
strict alignment architectures such that we can always m_adj to make sure the
packets are properly aligned.  This wastes some memory but simplifies things
considerably.  Hopefully we can reduce the spillage in the near future by
taking advantage of recent improvements in the pool code.

ok mpi@, mikeb@, dlg@

1 files changed, 7 insertions, 7 deletions

diff --git a/sys/dev/pci/if_em.h b/sys/dev/pci/if_em.h
index da4144784fc..f58051644b7 100644
--- a/sys/dev/pci/if_em.h
+++ b/sys/dev/pci/if_em.h
@@ -32,7 +32,7 @@ POSSIBILITY OF SUCH DAMAGE.
 ***************************************************************************/
 
 /* $FreeBSD: if_em.h,v 1.26 2004/09/01 23:22:41 pdeuskar Exp $ */
-/* $OpenBSD: if_em.h,v 1.55 2015/08/21 09:16:06 kettenis Exp $ */
+/* $OpenBSD: if_em.h,v 1.56 2015/08/26 09:17:20 kettenis Exp $ */
 
 #ifndef _EM_H_DEFINED_
 #define _EM_H_DEFINED_
@@ -266,6 +266,12 @@ typedef int	boolean_t;
 #define EM_RXBUFFER_8192	8192
 #define EM_RXBUFFER_16384	16384
 
+#ifdef __STRICT_ALIGNMENT
+#define EM_MCLBYTES		(EM_RXBUFFER_2048 + ETHER_ALIGN)
+#else
+#define EM_MCLBYTES		EM_RXBUFFER_2048
+#endif
+
 #define EM_MAX_SCATTER		64
 #define EM_TSO_SIZE		65535
 
@@ -324,12 +330,6 @@ struct em_softc {
 	struct timeout	timer_handle;
 	struct timeout	tx_fifo_timer_handle;
 
-#ifdef __STRICT_ALIGNMENT
-	/* Used for carrying forward alignment adjustments */
-	unsigned char	align_buf[ETHER_ALIGN];	/* tail of unaligned packet */
-	u_int8_t	align_buf_len;		/* bytes in tail */
-#endif /* __STRICT_ALIGNMENT */
-
 	/* Info about the board itself */
 	u_int32_t	part_num;
 	u_int8_t	link_active;