Re: [PATCH 6/6] treewide: remove check of list iterator against head past the loop body

Dan Carpenter
2022-02-28T13:15:53Z

On Mon, Feb 28, 2022 at 12:08:22PM +0100, Jakob Koschel wrote:
> diff --git a/drivers/infiniband/hw/hfi1/tid_rdma.c b/drivers/infiniband/hw/hfi1/tid_rdma.c
> index 2a7abf7a1f7f..a069847b56aa 100644
> --- a/drivers/infiniband/hw/hfi1/tid_rdma.c
> +++ b/drivers/infiniband/hw/hfi1/tid_rdma.c
> @@ -1239,7 +1239,7 @@ static int kern_alloc_tids(struct tid_rdma_flow *flow)
> struct hfi1_ctxtdata *rcd = flow->req->rcd;
> struct hfi1_devdata *dd = rcd->dd;
> u32 ngroups, pageidx = 0;
> - struct tid_group *group = NULL, *used;
> + struct tid_group *group = NULL, *used, *tmp;
> u8 use;
>
> flow->tnode_cnt = 0;
> @@ -1248,13 +1248,15 @@ static int kern_alloc_tids(struct tid_rdma_flow *flow)
> goto used_list;
>
> /* First look at complete groups */
> - list_for_each_entry(group, &rcd->tid_group_list.list, list) {
> - kern_add_tid_node(flow, rcd, "complete groups", group,
> - group->size);
> + list_for_each_entry(tmp, &rcd->tid_group_list.list, list) {
> + kern_add_tid_node(flow, rcd, "complete groups", tmp,
> + tmp->size);
>
> - pageidx += group->size;
> - if (!--ngroups)
> + pageidx += tmp->size;
> + if (!--ngroups) {
> + group = tmp;
> break;
> + }
> }
>
> if (pageidx >= flow->npagesets)
> @@ -1277,7 +1279,7 @@ static int kern_alloc_tids(struct tid_rdma_flow *flow)
> * However, if we are at the head, we have reached the end of the
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> * complete groups list from the first loop above
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> */

Originally this code tested for an open code list_is_head() so the
comment made sense, but it's out of date now. Just delete it.

> - if (group && &group->list == &rcd->tid_group_list.list)
> + if (!group)
> goto bail_eagain;
> group = list_prepare_entry(group, &rcd->tid_group_list.list,
> list);

regards,
dan carpenter