Re: [PATCH v4 0/7] ioctl()-based API to query VMAs from /proc//maps

Andrew Morton
2024-06-11T18:59:51Z

(Please cc Alexey on procfs changes)

On Tue, 11 Jun 2024 04:00:48 -0700 Andrii Nakryiko <andrii@kernel.org> wrote:

> Implement binary ioctl()-based interface to /proc/<pid>/maps file to allow
> applications to query VMA information more efficiently than reading *all* VMAs
> nonselectively through text-based interface of /proc/<pid>/maps file.

Looks nice but I'll await further reviewer input.

>
> ...
>
> Documentation/filesystems/proc.rst | 9 +
> fs/proc/task_mmu.c | 366 +++++++++++--
> include/uapi/linux/fs.h | 156 +++++-
> tools/include/uapi/linux/fs.h | 550 ++++++++++++++++++++
> tools/testing/selftests/bpf/.gitignore | 1 +
> tools/testing/selftests/bpf/Makefile | 2 +-
> tools/testing/selftests/bpf/procfs_query.c | 386 ++++++++++++++
> tools/testing/selftests/bpf/test_progs.c | 3 +
> tools/testing/selftests/bpf/test_progs.h | 2 +
> tools/testing/selftests/bpf/trace_helpers.c | 104 +++-
> 10 files changed, 1508 insertions(+), 71 deletions(-)
> create mode 100644 tools/include/uapi/linux/fs.h
> create mode 100644 tools/testing/selftests/bpf/procfs_query.c

Should the selftests be under bpf/? This is a procfs feature which
could be used by many things apart from bpf and it really isn't a bpf
thing at all. Wouldn't tools/testing/selftests/proc/ be a more
appropriate place?