examples/l3fwd: fix NEON instructions

To group consecutive packets with same destination port in bursts of 4
neon intrinsic data types dp1 and dp2 are calculated such that if
dst_port[]={a,b,c,d,e,f,g,h,i...} dp1 should contain: <a,b,c,d> and
dp2 should contain: <b,c,d,e> in the first iteration. dp1 should
be <e,f,g,h> and dp2 should be <f,g,h,i> in the next iteration.

Whereas the existing code incorrectly calculates dp1 as <d,e,f,g> from
second iteration.

This patch fixes the incorrect ARM NEON instructions on dp1.

Fixes: 569b290cdb36 ("examples/l3fwd: add NEON implementation")
Cc: stable@dpdk.org
Signed-off-by: Guduri Prathyusha <gprathyusha@caviumnetworks.com>
Acked-by: Jianbo Liu <jianbo.liu@arm.com>
Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>

diff --git a/examples/l3fwd/l3fwd_neon.h b/examples/l3fwd/l3fwd_neon.h
index 42d50d3..4bc1613 100644 (file)
--- a/examples/l3fwd/l3fwd_neon.h
+++ b/examples/l3fwd/l3fwd_neon.h
@@ -192,7 +192,7 @@ send_packets_multi(struct lcore_conf *qconf, struct rte_mbuf **pkts_burst,
                         * dp1:
                         * <d[j], d[j+1], d[j+2], d[j+3], ... >
                         */
-                       dp1 = vextq_u16(dp1, dp1, FWDSTEP - 1);
+                       dp1 = vextq_u16(dp2, dp1, FWDSTEP - 1);
                }
 
                /*