[dpdk-dev] [PATCH] net/i40e: fix received packets number for ARM vPMD

[Jianbo Liu]

Fix i40e stop receiving on ARM, as the statuses of RX descriptors
are not consistent, which is caused by cacheable hugepages.

Fixes: ae0eb310f253 ("net/i40e: implement vector PMD for ARM")
Cc: sta...@dpdk.org

Signed-off-by: Jianbo Liu <jianbo....@arm.com>
---
 drivers/net/i40e/i40e_rxtx_vec_neon.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/net/i40e/i40e_rxtx_vec_neon.c 
b/drivers/net/i40e/i40e_rxtx_vec_neon.c
index d0e6040..c9b4a28 100644
--- a/drivers/net/i40e/i40e_rxtx_vec_neon.c
+++ b/drivers/net/i40e/i40e_rxtx_vec_neon.c
@@ -197,8 +197,7 @@
 }
 
 #define PKTLEN_SHIFT     10
-
-#define I40E_VPMD_DESC_DD_MASK 0x0001000100010001ULL
+#define I40E_UINT16_BIT (CHAR_BIT * sizeof(uint16_t))
 
 static inline void
 desc_to_ptype_v(uint64x2_t descs[4], struct rte_mbuf **rx_pkts,
@@ -230,7 +229,6 @@
        struct i40e_rx_entry *sw_ring;
        uint16_t nb_pkts_recd;
        int pos;
-       uint64_t var;
        uint32_t *ptype_tbl = rxq->vsi->adapter->ptype_tbl;
 
        /* mask to shuffle from desc. to mbuf */
@@ -364,7 +362,6 @@
                /* C.2 get 4 pkts staterr value  */
                staterr = vzipq_u16(sterr_tmp1.val[1],
                                    sterr_tmp2.val[1]).val[0];
-               stat = vgetq_lane_u64(vreinterpretq_u64_u16(staterr), 0);
 
                desc_to_olflags_v(rxq, descs, &rx_pkts[pos]);
 
@@ -429,6 +426,12 @@
                        rx_pkts[pos + 3]->next = NULL;
                }
 
+               staterr = vshlq_n_u16(staterr, I40E_UINT16_BIT - 1);
+               staterr = vreinterpretq_u16_s16(
+                               vshrq_n_s16(vreinterpretq_s16_u16(staterr),
+                                           I40E_UINT16_BIT - 1));
+               stat = ~vgetq_lane_u64(vreinterpretq_u64_u16(staterr), 0);
+
                rte_prefetch_non_temporal(rxdp + RTE_I40E_DESCS_PER_LOOP);
 
                /* D.3 copy final 1,2 data to rx_pkts */
@@ -438,10 +441,12 @@
                         pkt_mb1);
                desc_to_ptype_v(descs, &rx_pkts[pos], ptype_tbl);
                /* C.4 calc avaialbe number of desc */
-               var = __builtin_popcountll(stat & I40E_VPMD_DESC_DD_MASK);
-               nb_pkts_recd += var;
-               if (likely(var != RTE_I40E_DESCS_PER_LOOP))
+               if (unlikely(stat == 0)) {
+                       nb_pkts_recd += RTE_I40E_DESCS_PER_LOOP;
+               } else {
+                       nb_pkts_recd += __builtin_ctzl(stat) / I40E_UINT16_BIT;
                        break;
+               }
        }
 
        /* Update our internal tail pointer */
-- 
1.9.1