For 'rte_pktmbuf_prefree_seg' function, 'rte_mbuf_refcnt_read(m) == 1' and '__rte_mbuf_refcnt_update(m, -1) == 0' are the same cases where mbuf's refcnt value should be 1. Thus we can simplify the code and remove the redundant part.
Furthermore, according to [1], when the mbuf is stored inside the mempool, the m->refcnt value should be 1. And then it is detached from its parent for an indirect mbuf. Thus change the description of 'rte_pktmbuf_prefree_seg' function. [1] https://patches.dpdk.org/project/dpdk/patch/20170404162807.20157-4-olivier.m...@6wind.com/ Suggested-by: Ruifeng Wang <ruifeng.w...@arm.com> Signed-off-by: Feifei Wang <feifei.wa...@arm.com> --- lib/mbuf/rte_mbuf.h | 22 +++------------------- 1 file changed, 3 insertions(+), 19 deletions(-) diff --git a/lib/mbuf/rte_mbuf.h b/lib/mbuf/rte_mbuf.h index 286b32b788..42e9b50d51 100644 --- a/lib/mbuf/rte_mbuf.h +++ b/lib/mbuf/rte_mbuf.h @@ -1328,7 +1328,7 @@ static inline int __rte_pktmbuf_pinned_extbuf_decref(struct rte_mbuf *m) * * This function does the same than a free, except that it does not * return the segment to its pool. - * It decreases the reference counter, and if it reaches 0, it is + * It decreases the reference counter, and if it reaches 1, it is * detached from its parent for an indirect mbuf. * * @param m @@ -1358,25 +1358,9 @@ rte_pktmbuf_prefree_seg(struct rte_mbuf *m) m->nb_segs = 1; return m; - - } else if (__rte_mbuf_refcnt_update(m, -1) == 0) { - - if (!RTE_MBUF_DIRECT(m)) { - rte_pktmbuf_detach(m); - if (RTE_MBUF_HAS_EXTBUF(m) && - RTE_MBUF_HAS_PINNED_EXTBUF(m) && - __rte_pktmbuf_pinned_extbuf_decref(m)) - return NULL; - } - - if (m->next != NULL) - m->next = NULL; - if (m->nb_segs != 1) - m->nb_segs = 1; - rte_mbuf_refcnt_set(m, 1); - - return m; } + + __rte_mbuf_refcnt_update(m, -1); return NULL; } -- 2.25.1
