Re: [PATCH v1 08/13] test/bbdev: extend support for large TB

[Maxime Coquelin]

On 2/13/23 21:20, Vargas, Hernan wrote:

Hi Maxime,

-----Original Message-----
From: Maxime Coquelin <maxime.coque...@redhat.com>
Sent: Tuesday, January 31, 2023 5:29 AM
To: Vargas, Hernan <hernan.var...@intel.com>; dev@dpdk.org;
gak...@marvell.com; Rix, Tom <t...@redhat.com>
Cc: Chautru, Nicolas <nicolas.chau...@intel.com>; Zhang, Qi Z
<qi.z.zh...@intel.com>
Subject: Re: [PATCH v1 08/13] test/bbdev: extend support for large TB



On 1/17/23 17:50, Hernan Vargas wrote:

Add support for large TB when it cannot fit into a true mbuf.

Signed-off-by: Hernan Vargas <hernan.var...@intel.com>
---
   app/test-bbdev/test_bbdev_perf.c | 21 ++++++++++++---------
   1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/app/test-bbdev/test_bbdev_perf.c
b/app/test-bbdev/test_bbdev_perf.c
index 69b86cdeb1..fdf7a28ba2 100644
--- a/app/test-bbdev/test_bbdev_perf.c
+++ b/app/test-bbdev/test_bbdev_perf.c
@@ -1072,8 +1072,6 @@ init_op_data_objs(struct rte_bbdev_op_data

*bufs,

                         * Special case when DPDK mbuf cannot handle
                         * the required input size
                         */
-                       printf("Warning: Larger input size than DPDK mbuf

%d\n",

-                                       seg->length);
                        large_input = true;
                }
                bufs[i].data = m_head;
@@ -2030,6 +2028,7 @@ validate_op_chain(struct rte_bbdev_op_data

*op,

        struct rte_mbuf *m = op->data;
        uint8_t nb_dst_segments = orig_op->nb_segments;
        uint32_t total_data_size = 0;
+       bool ignore_mbuf = false; /* ignore mbuf limitations */

        TEST_ASSERT(nb_dst_segments == m->nb_segs,
                        "Number of segments differ in original (%u) and filled

(%u) op",

@@ -2042,21 +2041,25 @@ validate_op_chain(struct rte_bbdev_op_data

*op,

                uint16_t data_len = rte_pktmbuf_data_len(m) - offset;
                total_data_size += orig_op->segments[i].length;

-               TEST_ASSERT(orig_op->segments[i].length == data_len,
-                               "Length of segment differ in original (%u) and

filled (%u) op",

-                               orig_op->segments[i].length, data_len);
+               if (orig_op->segments[i].length >

RTE_BBDEV_LDPC_E_MAX_MBUF)

+                       ignore_mbuf = true;
+               if (!ignore_mbuf)
+                       TEST_ASSERT(orig_op->segments[i].length ==

data_len,

+                                       "Length of segment differ in original

(%u) and filled (%u) op",

+                                       orig_op->segments[i].length,

data_len);

                TEST_ASSERT_BUFFERS_ARE_EQUAL(orig_op-
segments[i].addr,
                                rte_pktmbuf_mtod_offset(m, uint32_t *,

offset),

-                               data_len,
+                               orig_op->segments[i].length,

Isn't it ending up in performing out of bounds access in the mbuf?

No, in the case when ignore_mbuf is set to true, we use a "fake" mbuf allocated 
in memory with rte_malloc.
The size allocated is segments[i].length.

Ok.

Thanks,
Maxime

Thanks

                                "Output buffers (CB=%u) are not equal", i);
                m = m->next;
        }

        /* Validate total mbuf pkt length */
        uint32_t pkt_len = rte_pktmbuf_pkt_len(op->data) - op->offset;
-       TEST_ASSERT(total_data_size == pkt_len,
-                       "Length of data differ in original (%u) and filled (%u)

op",

-                       total_data_size, pkt_len);
+       if (!ignore_mbuf)
+               TEST_ASSERT(total_data_size == pkt_len,
+                               "Length of data differ in original (%u) and

filled (%u) op",

+                               total_data_size, pkt_len);

        return TEST_SUCCESS;
   }