lkml.org 
[lkml]   [2019]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH v7 perf, bpf-next 0/8] reveal invisible bpf programs
Date
This set catches symbol for all bpf programs loaded/unloaded
before/during/after perf-record run PERF_RECORD_KSYMBOL and
PERF_RECORD_BPF_EVENT.

PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT includes key information
of a bpf program load and unload. They are sent through perf ringbuffer,
and stored in perf.data. PERF_RECORD_KSYMBOL includes basic information
for simple profiling. It is ON by default. PERF_RECORD_BPF_EVENT is
used to gather more information of the bpf program. It is necessary for
perf-annotate of bpf programs.

Before this patch, perf-report will not be able to recover symbols of
bpf programs once the programs are unloaded.

This is to follow up Alexei's early effort [2] to show bpf programs via
mmap events.

Thanks,
Song

Changes v6 -> PATCH v7:
1. Split "[3/7] introduce PERF_RECORD_BPF_EVENT" into two commits:
[3/8] introduce PERF_RECORD_BPF_EVENT
[5/8] emit PERF_RECORD_KSYMBOL for BPF program load/unload

Changes v5 -> PATCH v6:
1. Reduce len in PERF_RECORD_KSYMBOL from u64 to u32. Use the 32 free bits
for ksym_type (u16) and flags (u16).

Changes v4 -> PATCH v5:
1. Fixed build error reported by kbuild test bot.

Changes v3 -> PATCH v4:
1. Split information about bpf program into PERF_RECORD_KSYMBOL (with
name, addr, len); and PERF_RECORD_BPF_EVENT PERF_RECORD_BPF_EVENT
(with id, tag);
2. Split the implementation in kernel and user space.

Changes v2 -> PATCH v3:
1. Rebase on bpf-next tree, and on top of BPF sub program tag patches [1]
for latest information in bpf_prog_info.
2. Complete handling and synthesizing PERF_RECORD_BPF_EVENT in perf.

Changes v1 -> PATCH v2:
1. Only 3 of the 5 patches in v1, to focus on ABI first;
2. Generate PERF_RECORD_BPF_EVENT per bpf sub program instead of per prog;
3. Modify PERF_RECORD_BPF_EVENT with more details (addr, len, name),
so that it can be used for basic profiling without calling sys_bpf.

Changes RFC -> PATCH v1:
1. In perf-record, poll vip events in a separate thread;
2. Add tag to bpf prog name;
3. Small refactorings.

[1] https://patchwork.ozlabs.org/project/netdev/list/?series=81037
[2] https://www.spinics.net/lists/netdev/msg524232.html

Song Liu (8):
perf, bpf: Introduce PERF_RECORD_KSYMBOL
sync tools/include/uapi/linux/perf_event.h
perf, bpf: introduce PERF_RECORD_BPF_EVENT
sync tools/include/uapi/linux/perf_event.h
perf, bpf: emit PERF_RECORD_KSYMBOL for BPF program load/unload
perf util: handle PERF_RECORD_KSYMBOL
perf util: handle PERF_RECORD_BPF_EVENT
perf tools: synthesize PERF_RECORD_* for loaded BPF programs

include/linux/filter.h | 7 +
include/linux/perf_event.h | 19 +++
include/uapi/linux/perf_event.h | 53 ++++++-
kernel/bpf/core.c | 2 +-
kernel/bpf/syscall.c | 2 +
kernel/events/core.c | 218 ++++++++++++++++++++++++-
tools/include/uapi/linux/perf_event.h | 53 ++++++-
tools/perf/builtin-record.c | 7 +
tools/perf/perf.h | 1 +
tools/perf/util/Build | 2 +
tools/perf/util/bpf-event.c | 220 ++++++++++++++++++++++++++
tools/perf/util/bpf-event.h | 16 ++
tools/perf/util/event.c | 41 +++++
tools/perf/util/event.h | 36 +++++
tools/perf/util/evsel.c | 19 +++
tools/perf/util/evsel.h | 2 +
tools/perf/util/machine.c | 60 +++++++
tools/perf/util/machine.h | 3 +
tools/perf/util/session.c | 8 +
tools/perf/util/tool.h | 5 +-
20 files changed, 769 insertions(+), 5 deletions(-)
create mode 100644 tools/perf/util/bpf-event.c
create mode 100644 tools/perf/util/bpf-event.h

--
2.17.1

\
 
 \ /
  Last update: 2019-01-11 01:20    [W:0.089 / U:23.076 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site