Re: [PATCH bpf-next v3 0/3] Parameterize task iterators.

[Jiri Olsa <olsajiri@gmail.com>]

On Mon, Aug 08, 2022 at 11:34:58PM -0700, Kui-Feng Lee wrote:
> Allow creating an iterator that loops through resources of one task/thread.
> 
> People could only create iterators to loop through all resources of
> files, vma, and tasks in the system, even though they were interested in only the
> resources of a specific task or process.  Passing the addintional
> parameters, people can now create an iterator to go through all
> resources or only the resources of a task.
> 
> Major Changes:
> 
>  - Add new parameters in bpf_iter_link_info to indicate to go through
>    all tasks or to go through a specific task.
> 
>  - Change the implementations of BPF iterators of vma, files, and
>    tasks to allow going through only the resources of a specific task.
> 
>  - Provide the arguments of parameterized task iterators in
>    bpf_link_info.
> 
> Differences from v2:
> 
>  - Supports tid, tgid, and pidfd.
> 
>  - Change 'type' from __u8 to enum bpf_task_iter_type.

hi,
I'm getting test fail:

test_task_:PASS:bpf_iter_task__open_and_load 0 nsec
test_task_:PASS:pthread_mutex_init 0 nsec
test_task_:PASS:pthread_mutex_lock 0 nsec
test_task_:PASS:pthread_create 0 nsec
do_dummy_read:PASS:attach_iter 0 nsec
do_dummy_read:PASS:create_iter 0 nsec
do_dummy_read:PASS:read 0 nsec
test_task_:PASS:pthread_mutex_unlock 0 nsec
test_task_:FAIL:check_num_unknown_tid unexpected check_num_unknown_tid: actual 0 != expected 1
test_task_:PASS:check_num_known_tid 0 nsec
test_task_:PASS:pthread_join 0 nsec
test_task_:PASS:bpf_iter_task__open_and_load 0 nsec
test_task_:PASS:pthread_mutex_init 0 nsec
test_task_:PASS:pthread_mutex_lock 0 nsec
test_task_:PASS:pthread_create 0 nsec
do_dummy_read:PASS:attach_iter 0 nsec
do_dummy_read:PASS:create_iter 0 nsec
do_dummy_read:PASS:read 0 nsec
test_task_:PASS:pthread_mutex_unlock 0 nsec
test_task_:FAIL:check_num_unknown_tid unexpected check_num_unknown_tid: actual 134 != expected 1
test_task_:PASS:check_num_known_tid 0 nsec
test_task_:PASS:pthread_join 0 nsec
#10/5    bpf_iter/task:FAIL

jirka

> 
> v2: https://lore.kernel.org/bpf/20220801232649.2306614-1-kuifeng@fb.com/
> v1: https://lore.kernel.org/bpf/20220726051713.840431-1-kuifeng@fb.com/
> 
> Kui-Feng Lee (3):
>   bpf: Parameterize task iterators.
>   bpf: Handle bpf_link_info for the parameterized task BPF iterators.
>   selftests/bpf: Test parameterized task BPF iterators.
> 
>  include/linux/bpf.h                           |   8 +
>  include/uapi/linux/bpf.h                      |  43 +++
>  kernel/bpf/task_iter.c                        | 153 +++++++++--
>  tools/include/uapi/linux/bpf.h                |  43 +++
>  .../selftests/bpf/prog_tests/bpf_iter.c       | 251 ++++++++++++++++--
>  .../selftests/bpf/prog_tests/btf_dump.c       |   2 +-
>  .../selftests/bpf/progs/bpf_iter_task.c       |   9 +
>  .../selftests/bpf/progs/bpf_iter_task_file.c  |   7 +
>  .../selftests/bpf/progs/bpf_iter_task_vma.c   |   6 +-
>  9 files changed, 474 insertions(+), 48 deletions(-)
> 
> -- 
> 2.30.2
>