From: Jean-Mickael Guerin <jean-mickael.guerin@6wind.com>
Date: Thu, 4 Dec 2014 14:26:20 +0000 (+0100)
Subject: ixgbe: fix setup of mbuf initializer template
X-Git-Tag: spdx-start~9973
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=661dfdf09ffc822621722ae9af46f1d7e080d0a5;p=dpdk.git

ixgbe: fix setup of mbuf initializer template

Add a compiler barrier to make sure all fields covered by
the marker rearm_data are assigned before the read.

Fixes: 0ff3324da2 ("ixgbe: rework vector pmd following mbuf changes")

Signed-off-by: Jean-Mickael Guerin <jean-mickael.guerin@6wind.com>
Acked-by: David Marchand <david.marchand@6wind.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
---

diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx_vec.c b/lib/librte_pmd_ixgbe/ixgbe_rxtx_vec.c
index 579bc46fb6..c1b5a781c0 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_rxtx_vec.c
+++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx_vec.c
@@ -739,6 +739,9 @@ ixgbe_rxq_vec_setup(struct igb_rx_queue *rxq)
 	mb_def.buf_len = rxq->mb_pool->elt_size - sizeof(struct rte_mbuf);
 	mb_def.port = rxq->port_id;
 	rte_mbuf_refcnt_set(&mb_def, 1);
+
+	/* prevent compiler reordering: rearm_data covers previous fields */
+	rte_compiler_barrier();
 	rxq->mbuf_initializer = *((uint64_t *)&mb_def.rearm_data);
 	return 0;
 }