From b25f49d8e1aea0c6fbfd31abdd8197d9815b9e0a Mon Sep 17 00:00:00 2001 From: Bruce Richardson Date: Fri, 28 Apr 2017 17:21:14 +0100 Subject: [PATCH] net/i40e: add compile-time checks to vector driver The vector PMD is very sensitive to the layout of the mbuf, especially on the RX path. Add in some compile-time checks to make sure the mbuf layout assumptions are valid, and to provide hints to anyone changing the mbuf where things may need to be updated. Signed-off-by: Bruce Richardson --- drivers/net/i40e/i40e_rxtx_vec_sse.c | 30 ++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/drivers/net/i40e/i40e_rxtx_vec_sse.c b/drivers/net/i40e/i40e_rxtx_vec_sse.c index 3b4a352eb4..a439b1ef5d 100644 --- a/drivers/net/i40e/i40e_rxtx_vec_sse.c +++ b/drivers/net/i40e/i40e_rxtx_vec_sse.c @@ -87,6 +87,8 @@ i40e_rxq_rearm(struct i40e_rx_queue *rxq) mb1 = rxep[1].mbuf; /* load buf_addr(lo 64bit) and buf_physaddr(hi 64bit) */ + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, buf_physaddr) != + offsetof(struct rte_mbuf, buf_addr) + 8); vaddr0 = _mm_loadu_si128((__m128i *)&mb0->buf_addr); vaddr1 = _mm_loadu_si128((__m128i *)&mb1->buf_addr); @@ -203,6 +205,12 @@ desc_to_olflags_v(struct i40e_rx_queue *rxq, __m128i descs[4] __rte_unused, rearm1 = _mm_blend_epi16(mbuf_init, _mm_slli_si128(vlan0, 4), 0x10); rearm2 = _mm_blend_epi16(mbuf_init, vlan0, 0x10); rearm3 = _mm_blend_epi16(mbuf_init, _mm_srli_si128(vlan0, 4), 0x10); + + /* write the rearm data and the olflags in one write */ + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, ol_flags) != + offsetof(struct rte_mbuf, rearm_data) + 8); + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, rearm_data) != + RTE_ALIGN(offsetof(struct rte_mbuf, rearm_data), 16)); _mm_store_si128((__m128i *)&rx_pkts[0]->rearm_data, rearm0); _mm_store_si128((__m128i *)&rx_pkts[1]->rearm_data, rearm1); _mm_store_si128((__m128i *)&rx_pkts[2]->rearm_data, rearm2); @@ -252,6 +260,15 @@ _recv_raw_pkts_vec(struct i40e_rx_queue *rxq, struct rte_mbuf **rx_pkts, -rxq->crc_len, /* sub crc on pkt_len */ 0, 0 /* ignore pkt_type field */ ); + /* + * compile-time check the above crc_adjust layout is correct. + * NOTE: the first field (lowest address) is given last in set_epi16 + * call above. + */ + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, pkt_len) != + offsetof(struct rte_mbuf, rx_descriptor_fields1) + 4); + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, data_len) != + offsetof(struct rte_mbuf, rx_descriptor_fields1) + 8); __m128i dd_check, eop_check; /* nb_pkts shall be less equal than RTE_I40E_MAX_RX_BURST */ @@ -296,6 +313,19 @@ _recv_raw_pkts_vec(struct i40e_rx_queue *rxq, struct rte_mbuf **rx_pkts, 0xFF, 0xFF, /* pkt_type set as unknown */ 0xFF, 0xFF /*pkt_type set as unknown */ ); + /* + * Compile-time verify the shuffle mask + * NOTE: some field positions already verified above, but duplicated + * here for completeness in case of future modifications. + */ + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, pkt_len) != + offsetof(struct rte_mbuf, rx_descriptor_fields1) + 4); + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, data_len) != + offsetof(struct rte_mbuf, rx_descriptor_fields1) + 8); + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, vlan_tci) != + offsetof(struct rte_mbuf, rx_descriptor_fields1) + 10); + RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, hash) != + offsetof(struct rte_mbuf, rx_descriptor_fields1) + 12); /* Cache is empty -> need to scan the buffer rings, but first move * the next 'n' mbufs into the cache -- 2.20.1