On Tue, Jan 10, 2017 at 04:25:23PM -0800, Alexei Starovoitov wrote:
> On Tue, Jan 10, 2017 at 03:02:07PM +0100, Tobias Klauser wrote:
> > Remove the unused but set variable 'first_node' in
> > __bpf_lru_list_shrink_inactive() to fix the following GCC warning when
> > building with 'W=1':
> >
> > kernel/bpf/bpf_lru_list.c:216:41: warning: variable ‘first_node’ set but
> > not used [-Wunused-but-set-variable]
> >
> > Cc: Martin KaFai Lau <ka...@fb.com>
> > Signed-off-by: Tobias Klauser <tklau...@distanz.ch>
> > ---
> > kernel/bpf/bpf_lru_list.c | 3 +--
> > 1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/kernel/bpf/bpf_lru_list.c b/kernel/bpf/bpf_lru_list.c
> > index 89b7ef41c86b..d78501ee0609 100644
> > --- a/kernel/bpf/bpf_lru_list.c
> > +++ b/kernel/bpf/bpf_lru_list.c
> > @@ -213,11 +213,10 @@ __bpf_lru_list_shrink_inactive(struct bpf_lru *lru,
> > enum bpf_lru_list_type tgt_free_type)
> > {
> > struct list_head *inactive = &l->lists[BPF_LRU_LIST_T_INACTIVE];
> > - struct bpf_lru_node *node, *tmp_node, *first_node;
> > + struct bpf_lru_node *node, *tmp_node;
> > unsigned int nshrinked = 0;
> > unsigned int i = 0;
> >
> > - first_node = list_first_entry(inactive, struct bpf_lru_node, list);
> > list_for_each_entry_safe_reverse(node, tmp_node, inactive, list) {
> > if (bpf_lru_node_is_ref(node)) {
> > __bpf_lru_node_move(l, node, BPF_LRU_LIST_T_ACTIVE);
>
> Martin,
> I cannot tell whether it's actually copy-paste leftover
> or this patch is needed:
I made some changes to __bpf_lru_list_shrink_inactive() which made
first_node checking unnecessary but I did not remove first_node all
together by mistake.
__bpf_lru_list_rotate_active() pushes node back to the head, so we
need to remember the original first_node and break accordingly.
__bpf_lru_list_shrink_inactive() does not do that, so there is no
need to test against first_node.
