Re: [PATCH v1 00/10] Move uid filtering to BPF filters

From: Namhyung Kim
Date: Mon Feb 10 2025 - 14:59:33 EST


On Sat, Jan 11, 2025 at 11:01:33AM -0800, Ian Rogers wrote:
> Rather than scanning /proc and skipping PIDs based on their UIDs, use
> BPF filters for uid filtering. The /proc scanning in thread_map is
> racy as the PID may exit before the perf_event_open causing perf to
> abort. BPF UID filters are more robust as they avoid the race. Add a
> helper for commands that support UID filtering and wire up. Remove the
> non-BPF UID filtering support.

Hmm.. then non-BPF build cannot use the UID filtering anymore, right?
Also non-root users will be limited unless it pinned the BPF program in
advance.

I think you can keep the original behavior and convert to BPF only when
it's available.

Thanks,
Namhyung

>
> Ian Rogers (10):
> perf bench evlist-open-close: Reduce scope of 2 variables
> perf parse-events filter: Use evsel__find_pmu
> perf target: Separate parse_uid into its own function
> perf parse-events: Add parse_uid_filter helper
> perf record: Switch user option to use BPF filter
> perf top: Switch user option to use BPF filter
> perf trace: Switch user option to use BPF filter
> perf bench evlist-open-close: Switch user option to use BPF filter
> perf target: Remove uid from target
> perf thread_map: Remove uid options
>
> tools/perf/bench/evlist-open-close.c | 76 ++++++++++++---------
> tools/perf/builtin-ftrace.c | 1 -
> tools/perf/builtin-kvm.c | 2 -
> tools/perf/builtin-record.c | 26 +++----
> tools/perf/builtin-stat.c | 4 +-
> tools/perf/builtin-top.c | 22 +++---
> tools/perf/builtin-trace.c | 25 ++++---
> tools/perf/tests/backward-ring-buffer.c | 1 -
> tools/perf/tests/event-times.c | 8 +--
> tools/perf/tests/keep-tracking.c | 2 +-
> tools/perf/tests/mmap-basic.c | 2 +-
> tools/perf/tests/openat-syscall-all-cpus.c | 2 +-
> tools/perf/tests/openat-syscall-tp-fields.c | 1 -
> tools/perf/tests/openat-syscall.c | 2 +-
> tools/perf/tests/perf-record.c | 1 -
> tools/perf/tests/perf-time-to-tsc.c | 2 +-
> tools/perf/tests/switch-tracking.c | 2 +-
> tools/perf/tests/task-exit.c | 1 -
> tools/perf/tests/thread-map.c | 2 +-
> tools/perf/util/bpf-filter.c | 2 +-
> tools/perf/util/evlist.c | 3 +-
> tools/perf/util/parse-events.c | 25 ++++---
> tools/perf/util/parse-events.h | 1 +
> tools/perf/util/python.c | 10 +--
> tools/perf/util/target.c | 54 ++-------------
> tools/perf/util/target.h | 15 +---
> tools/perf/util/thread_map.c | 32 +--------
> tools/perf/util/thread_map.h | 6 +-
> tools/perf/util/top.c | 4 +-
> tools/perf/util/top.h | 1 +
> 30 files changed, 135 insertions(+), 200 deletions(-)
>
> --
> 2.47.1.613.gc27f4b7a9f-goog
>