vxge: improve tx performance by using mmiowb() instead of wmb()

wmb() is extremely heavy on x86.  The semantics required in the driver are
provided by mmiowb(), so use that and improve tx performance on P4 Xeons by
5-10%.

Signed-off-by: Benjamin LaHaise <ben.lahaise@neterion.com>
Signed-off-by: Sreenivasa Honnur <sreenivasa.honnur@neterion.com>
Signed-off-by: Ramkrishna Vepa <ram.vepa@neterion.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Benjamin LaHaise 2009-08-04 10:21:21 +00:00 committed by David S. Miller
parent ff67df55f6
commit ff1b974cf3

View File

@ -1070,11 +1070,11 @@ static void __vxge_hw_non_offload_db_post(struct __vxge_hw_fifo *fifo,
VXGE_HW_NODBW_GET_NO_SNOOP(no_snoop),
&fifo->nofl_db->control_0);
wmb();
mmiowb();
writeq(txdl_ptr, &fifo->nofl_db->txdl_ptr);
wmb();
mmiowb();
}
/**