On 8/19/22 3:09 PM, Kui-Feng Lee wrote:
Add new fields to bpf_link_info that users can query it through bpf_obj_get_info_by_fd(). Signed-off-by: Kui-Feng Lee <kuifeng@xxxxxx>
Acked-by: Yonghong Song <yhs@xxxxxx> But we are missing bpftool implementation which actually dumps the tid/pid here. So you need another bpftool patch to do this. See file tools/bpf/bpftool/link.c to see how map_id is printed.
--- include/uapi/linux/bpf.h | 6 ++++++ kernel/bpf/task_iter.c | 18 ++++++++++++++++++ tools/include/uapi/linux/bpf.h | 6 ++++++ 3 files changed, 30 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 778fbf11aa00..6647e052dd00 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -6170,6 +6170,12 @@ struct bpf_link_info { __u32 map_id; } map; }; + union { + struct { + __u32 tid; + __u32 pid; + } task; + }; } iter; struct { __u32 netns_ino; diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c index 2f5fc6602917..927b3a1cf354 100644 --- a/kernel/bpf/task_iter.c +++ b/kernel/bpf/task_iter.c @@ -596,6 +596,21 @@ static const struct bpf_iter_seq_info task_seq_info = { .seq_priv_size = sizeof(struct bpf_iter_seq_task_info), };+static int bpf_iter_fill_link_info(const struct bpf_iter_aux_info *aux, struct bpf_link_info *info)+{ + switch (aux->task.type) { + case BPF_TASK_ITER_TID: + info->iter.task.tid = aux->task.pid; + break; + case BPF_TASK_ITER_TGID: + info->iter.task.pid = aux->task.pid; + break; + default: + break; + } + return 0; +} + static struct bpf_iter_reg task_reg_info = { .target = "task", .attach_target = bpf_iter_attach_task, @@ -606,6 +621,7 @@ static struct bpf_iter_reg task_reg_info = { PTR_TO_BTF_ID_OR_NULL }, }, .seq_info = &task_seq_info, + .fill_link_info = bpf_iter_fill_link_info, };static const struct bpf_iter_seq_info task_file_seq_info = {@@ -627,6 +643,7 @@ static struct bpf_iter_reg task_file_reg_info = { PTR_TO_BTF_ID_OR_NULL }, }, .seq_info = &task_file_seq_info, + .fill_link_info = bpf_iter_fill_link_info, };static const struct bpf_iter_seq_info task_vma_seq_info = {@@ -648,6 +665,7 @@ static struct bpf_iter_reg task_vma_reg_info = { PTR_TO_BTF_ID_OR_NULL }, }, .seq_info = &task_vma_seq_info, + .fill_link_info = bpf_iter_fill_link_info, };BPF_CALL_5(bpf_find_vma, struct task_struct *, task, u64, start,diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 7a0268749a48..177722c5dd62 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -6170,6 +6170,12 @@ struct bpf_link_info { __u32 map_id; } map; }; + union { + struct { + __u32 tid; + __u32 pid; + } task; + }; } iter; struct { __u32 netns_ino;
