On 29/08/2022 20:23, Kui-Feng Lee wrote:
> Show tid or pid of iterators if giving an argument of tid or pid
>
> For example, the command `bpftool link list` may list following
> lines.
>
> 1: iter prog 2 target_name bpf_map
> 2: iter prog 3 target_name bpf_prog
> 33: iter prog 225 target_name task_file tid 1644
> pids test_progs(1644)
>
> Link 33 is a task_file iterator with tid 1644. For now, only targets
> of task, task_file and task_vma may be with tid or pid to filter out
> tasks other than those belonging to a process (pid) or a thread (tid).
>
> Signed-off-by: Kui-Feng Lee <kuifeng@xxxxxx>
> ---
> tools/bpf/bpftool/link.c | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/tools/bpf/bpftool/link.c b/tools/bpf/bpftool/link.c
> index 7a20931c3250..88937036fae0 100644
> --- a/tools/bpf/bpftool/link.c
> +++ b/tools/bpf/bpftool/link.c
> @@ -83,6 +83,13 @@ static bool is_iter_map_target(const char *target_name)
> strcmp(target_name, "bpf_sk_storage_map") == 0;
> }
>
> +static bool is_iter_task_target(const char *target_name)
> +{
> + return strcmp(target_name, "task") == 0 ||
> + strcmp(target_name, "task_file") == 0 ||
> + strcmp(target_name, "task_vma") == 0;
> +}
> +
> static void show_iter_json(struct bpf_link_info *info, json_writer_t *wtr)
> {
> const char *target_name = u64_to_ptr(info->iter.target_name);
> @@ -91,6 +98,12 @@ static void show_iter_json(struct bpf_link_info *info, json_writer_t *wtr)
>
> if (is_iter_map_target(target_name))
> jsonw_uint_field(wtr, "map_id", info->iter.map.map_id);
> + else if (is_iter_task_target(target_name)) {
> + if (info->iter.task.tid)
> + jsonw_uint_field(wtr, "tid", info->iter.task.tid);
> + else if (info->iter.task.pid)
> + jsonw_uint_field(wtr, "pid", info->iter.task.pid);
> + }
> }
>
> static int get_prog_info(int prog_id, struct bpf_prog_info *info)
> @@ -208,6 +221,12 @@ static void show_iter_plain(struct bpf_link_info *info)
>
> if (is_iter_map_target(target_name))
> printf("map_id %u ", info->iter.map.map_id);
> + else if (is_iter_task_target(target_name)) {
> + if (info->iter.task.tid)
> + printf("tid %u ", info->iter.task.tid);
> + else if (info->iter.task.pid)
> + printf("pid %u ", info->iter.task.pid);
> + }
> }
>
> static int show_link_close_plain(int fd, struct bpf_link_info *info)
Acked-by: Quentin Monnet <quentin@xxxxxxxxxxxxx>
Looks good to me, although this patch may conflict with
https://lore.kernel.org/bpf/20220829231828.1016835-1-haoluo@xxxxxxxxxx/t/#u
