[BLKTAP] No need for barrier when updating rsp_prod_pvt.

Signed-off-by: Keir Fraser <keir@xensource.com>

diff --git a/tools/blktap/drivers/tapdisk.c b/tools/blktap/drivers/tapdisk.c
index 236e4ca2cfdcca6514bfb18cde59cf9af401906c..0c9b623abe4c5a0d179fd2123b155606d87598bc 100644 (file)
--- a/tools/blktap/drivers/tapdisk.c
+++ b/tools/blktap/drivers/tapdisk.c
@@ -381,7 +381,6 @@ static inline int write_rsp_to_ring(struct td_state *s, blkif_response_t *rsp)
        
        rsp_d = RING_GET_RESPONSE(&info->fe_ring, info->fe_ring.rsp_prod_pvt);
        memcpy(rsp_d, rsp, sizeof(blkif_response_t));
-       wmb();
        info->fe_ring.rsp_prod_pvt++;
        
        return 0;