On Tue, 7 Apr 2020 16:45:59 +0100 Ferruh Yigit <ferruh.yi...@intel.com> wrote:
> On 4/7/2020 4:38 PM, Stephen Hemminger wrote: > > On Tue, 7 Apr 2020 16:15:16 +0100 > > Ferruh Yigit <ferruh.yi...@intel.com> wrote: > > > >>> +static void > >>> +tap_rxq_pool_free(struct rte_mbuf *pool) > >>> +{ > >>> + struct rte_mbuf *mbuf = pool; > >>> + uint16_t nb_segs = 1; > >>> + > >>> + if (mbuf == NULL) > >>> + return; > >>> + > >>> + while (mbuf->next) { > >>> + mbuf = mbuf->next; > >>> + nb_segs++; > >>> + } > >>> + pool->nb_segs = nb_segs; > >>> + rte_pktmbuf_free(pool); > >>> +} > > > > Since mbuf is going to be free, why bother with nb_segs. > > Since rte_pktmbuf_free takes NULL as an argument, and frees the m->next > > chain > > I don't see why not just > > rte_pktmbuf_free(pool) > > > > Chain is not constructed properly, 'nb_segs' is wrong, only > 'rte_pktmbuf_free()' > call won't free all the chain but first mbuf. > > This implementation is fixing 'nb_segs' sot that 'rte_pktmbuf_free()' can work > as you suggested. > > Or I suggest iterate the list and fix all mbufs, instead of fixing 'nb_segs', > this may be one iteration less. If you look at implementation of rte_pktmbuf_free() in current DPDK version it does not care what nb_segs is set to.