[PATCH -next v5 0/2] perf stat: Support inherit events for bperf

From: Tengda Wu
Date: Mon Oct 21 2024 - 07:13:23 EST


Hello,

Here is the 5th version of the series to support inherit events for bperf.
This version added the `inherit` flag for struct `target` instead of
`bpf_stat_opts`, and also fixed the logic when TGID w/o inherit.


bperf (perf-stat --bpf-counter) has not supported inherit events during
fork() since it was first introduced.

This patch series tries to add this support by:
1) adding two new bpf programs to monitor task lifecycle;
2) recording new tasks in the filter map dynamically;
3) reusing `accum_key` of parent task for new tasks.

Thanks,
Tengda


Changelog:
---------
v5: (Address comments from Namhyung, thanks)
* Add the `inherit` flag for struct `target` instead of `bpf_stat_opts`
* Fix the logic when TGID w/o inherit

v4: https://lore.kernel.org/all/20241012023225.151084-1-wutengda@xxxxxxxxxxxxxxx/
* Add an `inherit` flag to bperf to control inherit behavior

v3: https://lore.kernel.org/all/20240916014318.267709-1-wutengda@xxxxxxxxxxxxxxx/
* Use pid or tgid based on filter type in new_task prog
* Add comments to explain pid usage for TGID type in exit_task prog

v2: https://lore.kernel.org/all/20240905115918.772234-1-wutengda@xxxxxxxxxxxxxxx/
* Remove the unused init_filter_entries in follower bpf, declare
a global filter_entry_count in bpf_counter instead
* Attach on_newtask and on_exittask progs only if the filter type
is either PID or TGID

v1: https://lore.kernel.org/all/20240904123103.732507-1-wutengda@xxxxxxxxxxxxxxx/


Tengda Wu (2):
perf stat: Support inherit events during fork() for bperf
perf test: Use sqrtloop workload to test bperf event

tools/perf/builtin-stat.c | 1 +
tools/perf/tests/shell/stat_bpf_counters.sh | 2 +-
tools/perf/util/bpf_counter.c | 35 +++++--
tools/perf/util/bpf_skel/bperf_follower.bpf.c | 98 +++++++++++++++++--
tools/perf/util/bpf_skel/bperf_u.h | 5 +
tools/perf/util/target.h | 1 +
6 files changed, 127 insertions(+), 15 deletions(-)

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2.34.1