[dpdk-dev] [PATCH] examples/ipsec-secgw: limit inflight packets count

[Radu Nicolau]

Revert previous patch that introduce a performance
degradation in certain scenarios and add a configurable
limit for number inflight packets.

Revert
commit 84d4b5e4ec48 ("examples/ipsec-secgw: improve IPsec dequeue logic")
Cc: sta...@dpdk.org

Signed-off-by: Radu Nicolau <radu.nico...@intel.com>
---
 examples/ipsec-secgw/ipsec.c | 31 ++++++++++++++-----------------
 examples/ipsec-secgw/ipsec.h |  1 +
 2 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/examples/ipsec-secgw/ipsec.c b/examples/ipsec-secgw/ipsec.c
index 5fb5bc1..1b16b29 100644
--- a/examples/ipsec-secgw/ipsec.c
+++ b/examples/ipsec-secgw/ipsec.c
@@ -345,13 +345,18 @@ create_session(struct ipsec_ctx *ipsec_ctx, struct 
ipsec_sa *sa)
 static inline void
 enqueue_cop(struct cdev_qp *cqp, struct rte_crypto_op *cop)
 {
-       int32_t ret, i;
+       int32_t ret = 0, i;
 
        cqp->buf[cqp->len++] = cop;
 
        if (cqp->len == MAX_PKT_BURST) {
-               ret = rte_cryptodev_enqueue_burst(cqp->id, cqp->qp,
-                               cqp->buf, cqp->len);
+               int enq_size = cqp->len;
+               if (cqp->in_flight >= MAX_INFLIGHT)
+                       enq_size -= (int)(cqp->in_flight - MAX_INFLIGHT);
+
+               if (enq_size > 0)
+                       ret = rte_cryptodev_enqueue_burst(cqp->id, cqp->qp,
+                                       cqp->buf, enq_size);
                if (ret < cqp->len) {
                        RTE_LOG_DP(DEBUG, IPSEC, "Cryptodev %u queue %u:"
                                        " enqueued %u crypto ops out of %u\n",
@@ -486,9 +491,12 @@ ipsec_dequeue(ipsec_xform_fn xform_func, struct ipsec_ctx 
*ipsec_ctx,
        struct ipsec_sa *sa;
        struct rte_mbuf *pkt;
 
-       for (i = 0; i < ipsec_ctx->nb_qps && nb_pkts < max_pkts;) {
+       for (i = 0; i < ipsec_ctx->nb_qps && nb_pkts < max_pkts; i++) {
                struct cdev_qp *cqp;
-               cqp = &ipsec_ctx->tbl[ipsec_ctx->last_qp];
+
+               cqp = &ipsec_ctx->tbl[ipsec_ctx->last_qp++];
+               if (ipsec_ctx->last_qp == ipsec_ctx->nb_qps)
+                       ipsec_ctx->last_qp %= ipsec_ctx->nb_qps;
 
                while (ipsec_ctx->ol_pkts_cnt > 0 && nb_pkts < max_pkts) {
                        pkt = ipsec_ctx->ol_pkts[--ipsec_ctx->ol_pkts_cnt];
@@ -503,13 +511,8 @@ ipsec_dequeue(ipsec_xform_fn xform_func, struct ipsec_ctx 
*ipsec_ctx,
                        pkts[nb_pkts++] = pkt;
                }
 
-               if (cqp->in_flight == 0) {
-                       ipsec_ctx->last_qp++;
-                       if (ipsec_ctx->last_qp == ipsec_ctx->nb_qps)
-                               ipsec_ctx->last_qp %= ipsec_ctx->nb_qps;
-                       i++;
+               if (cqp->in_flight == 0)
                        continue;
-               }
 
                nb_cops = rte_cryptodev_dequeue_burst(cqp->id, cqp->qp,
                                cops, max_pkts - nb_pkts);
@@ -533,12 +536,6 @@ ipsec_dequeue(ipsec_xform_fn xform_func, struct ipsec_ctx 
*ipsec_ctx,
                                }
                        }
                        pkts[nb_pkts++] = pkt;
-                       if (cqp->in_flight < max_pkts) {
-                               ipsec_ctx->last_qp++;
-                               if (ipsec_ctx->last_qp == ipsec_ctx->nb_qps)
-                                       ipsec_ctx->last_qp %= ipsec_ctx->nb_qps;
-                               i++;
-                       }
                }
        }
 
diff --git a/examples/ipsec-secgw/ipsec.h b/examples/ipsec-secgw/ipsec.h
index 6059f6c..9ce912e 100644
--- a/examples/ipsec-secgw/ipsec.h
+++ b/examples/ipsec-secgw/ipsec.h
@@ -17,6 +17,7 @@
 #define RTE_LOGTYPE_IPSEC_IPIP  RTE_LOGTYPE_USER3
 
 #define MAX_PKT_BURST 32
+#define MAX_INFLIGHT 128
 #define MAX_QP_PER_LCORE 256
 
 #define MAX_DIGEST_SIZE 32 /* Bytes -- 256 bits */
-- 
2.7.5