On Sat, Mar 17, 2018 at 10:21:30PM -0400, Zhu Yanjun wrote: > In mcast recv process, the function skb_clone is used. In fact, > the refcount can be increased to replace cloning a new skb since > the original skb will not be modified before it is freed. > > This can make the performance better and save the memory. > > CC: Srinivas Eeda <srinivas.eeda@xxxxxxxxxx> > CC: Junxiao Bi <junxiao.bi@xxxxxxxxxx> > Signed-off-by: Zhu Yanjun <yanjun.zhu@xxxxxxxxxx> > --- > drivers/infiniband/sw/rxe/rxe_recv.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c > index 4c3f899..5b8f293 100644 > --- a/drivers/infiniband/sw/rxe/rxe_recv.c > +++ b/drivers/infiniband/sw/rxe/rxe_recv.c > @@ -309,10 +309,13 @@ static void rxe_rcv_mcast_pkt(struct rxe_dev *rxe, struct sk_buff *skb) > continue; > > /* if *not* the last qp in the list > - * make a copy of the skb to post to the next qp > + * make a reference of the skb to post to the next qp > */ > - skb_copy = (mce->qp_list.next != &mcg->qp_list) ? > - skb_clone(skb, GFP_ATOMIC) : NULL; > + skb_copy = NULL; > + if (mce->qp_list.next != &mcg->qp_list) { > + skb_copy = skb; > + refcount_inc(&skb->users); > + } Something with the code after the change doesn't make sense to me, you save skb in skb_copy (bad name after the change) and then, few lines below skb is set to skb_copy. I think with this change we do not really need skb_copy, just do refcount_inc. No comments about the idea itself, just the code structure. Not related to this proposal, while here, can you remove the "if (skb)" in label err1? looks like kfree_skb takes care of it. > > pkt->qp = qp; > rxe_add_ref(qp); > -- > 2.7.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html