On 10/2/17 4:48 PM, Alexei Starovoitov wrote:
> diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
> index 546113430049..70f679a94804 100644
> --- a/kernel/bpf/cgroup.c
> +++ b/kernel/bpf/cgroup.c
> @@ -27,129 +27,361 @@ void cgroup_bpf_put(struct cgroup *cgrp)
> {
> unsigned int type;
>
> - for (type = 0; type < ARRAY_SIZE(cgrp->bpf.prog); type++) {
> - struct bpf_prog *prog = cgrp->bpf.prog[type];
> -
> - if (prog) {
> - bpf_prog_put(prog);
> + for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) {
> + struct list_head *progs = &cgrp->bpf.progs[type];
> + struct bpf_prog_list *pl, *tmp;
> +
> + list_for_each_entry_safe(pl, tmp, progs, node) {
> + list_del(&pl->node);
> + bpf_prog_put(pl->prog);
> + kfree(pl);
> static_branch_dec(&cgroup_bpf_enabled_key);
> }
> + bpf_prog_array_free(cgrp->bpf.effective[type]);
> + }
> +}
> +
...
>
> - if (prog)
> - static_branch_inc(&cgroup_bpf_enabled_key);
> + /* all allocations were successful. Activate all prog arrays */
> + css_for_each_descendant_pre(css, &cgrp->self) {
> + struct cgroup *desc = container_of(css, struct cgroup, self);
>
> + activate_effective_progs(desc, type, desc->bpf.inactive);
> + desc->bpf.inactive = NULL;
> + }
> +
> + static_branch_inc(&cgroup_bpf_enabled_key);
> if (old_prog) {
> bpf_prog_put(old_prog);
> static_branch_dec(&cgroup_bpf_enabled_key);
> }
> return 0;
It's not clear to me that the static_branch_inc and static_branch_dec's
are equal since the dec is in the loop over each program in the list,
but the inc is not in a loop.
