On Jan 20, 2017, at 4:08 PM, Ferruh Yigit [off-list ref] wrote:

On 1/20/2017 12:19 AM, Ilya Matveychikov wrote:

quoted

mi->next will be assigned to NULL few lines later, trivial patch

Signed-off-by: Ilya V. Matveychikov <redacted>
---
lib/librte_mbuf/rte_mbuf.h | 1 -
1 file changed, 1 deletion(-)

diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index ead7c6e..5589d54 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h

@@ -1139,7 +1139,6 @@ static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *m)

	mi->buf_addr = m->buf_addr;
	mi->buf_len = m->buf_len;

-	mi->next = m->next;

Do you know why attaching mbuf is not supporting multi-segment?
Perhaps this can be documented in function comment, as one of the "not
supported" items.

No, I don’t know. For my application I’ve found that nb_segs with it’s limit in 256 segments is very annoying and I’ve decided not to use DPDK functions that dealt with nb_segs… But it is not about the rte_pktmbuf_attach() function and the patch.

Also, should we check mi->next before overwriting, in case it is not NULL?

quoted

	mi->data_off = m->data_off;
	mi->data_len = m->data_len;
	mi->port = m->port;

I don’t know. It depends of the usage. Will someone needs to chain two chains of mbuf?