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Subject[PATCH v4 0/6] enable creating [k,u]probe with perf_event_open
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Changes PATCH v3 to PATCH v4:
Remove uapi define MAX_PROBE_FUNC_NAME_LEN, use KSYM_NAME_LEN instead.
Add flag PERF_PROBE_CONFIG_IS_RETPROBE for config field of [k,u]probe.
Optimize ifdef's of CONFIG_KPROBE_EVENTS and CONFIG_UPROBE_EVENTS.
Optimize checks in perf_event_is_tracing().
Optimize perf_tp_register().

Changes PATCH v2 to PATCH v3:
Remove fixed type PERF_TYPE_KPROBE and PERF_TYPE_UPROBE, use dynamic
type instead.
Update userspace (samples/bpf, bcc) to look up type from sysfs.
Change License info in test_many_kprobe_user.c as Philippe Ombredanne
suggested.

Changes PATCH v1 to PATCH v2:
Split PERF_TYPE_PROBE into PERF_TYPE_KPROBE and PERF_TYPE_UPROBE.
Split perf_probe into perf_kprobe and perf_uprobe.
Remove struct probe_desc, use config1 and config2 instead.

Changes RFC v2 to PATCH v1:
Check type PERF_TYPE_PROBE in perf_event_set_filter().
Rebase on to tip perf/core.

Changes RFC v1 to RFC v2:
Fix build issue reported by kbuild test bot by adding ifdef of
CONFIG_KPROBE_EVENTS, and CONFIG_UPROBE_EVENTS.

RFC v1 cover letter:

This is to follow up the discussion over "new kprobe api" at Linux
Plumbers 2017:

https://www.linuxplumbersconf.org/2017/ocw/proposals/4808

With current kernel, user space tools can only create/destroy [k,u]probes
with a text-based API (kprobe_events and uprobe_events in tracefs). This
approach relies on user space to clean up the [k,u]probe after using them.
However, this is not easy for user space to clean up properly.

To solve this problem, we introduce a file descriptor based API.
Specifically, we extended perf_event_open to create [k,u]probe, and attach
this [k,u]probe to the file descriptor created by perf_event_open. These
[k,u]probe are associated with this file descriptor, so they are not
available in tracefs.

We reuse large portion of existing trace_kprobe and trace_uprobe code.
Currently, the file descriptor API does not support arguments as the
text-based API does. This should not be a problem, as user of the file
decriptor based API read data through other methods (bpf, etc.).

I also include a patch to to bcc, and a patch to man-page perf_even_open.
Please see the list below. A fork of bcc with this patch is also available
on github:

https://github.com/liu-song-6/bcc/tree/perf_event_open

Thanks,
Song

man-pages patch:
perf_event_open.2: add type kprobe and uprobe

bcc patch:
bcc: Try use new API to create [k,u]probe with perf_event_open

kernel patches:

Song Liu (6):
perf: prepare perf_event.h for new types perf_kprobe and perf_uprobe
perf: copy new perf_event.h to tools/include/uapi
perf: implement pmu perf_kprobe
perf: implement pmu perf_uprobe
bpf: add option for bpf_load.c to use perf_kprobe
bpf: add new test test_many_kprobe

include/linux/trace_events.h | 8 ++
include/uapi/linux/perf_event.h | 14 +++
kernel/events/core.c | 97 +++++++++++++++++-
kernel/trace/trace_event_perf.c | 104 +++++++++++++++++++
kernel/trace/trace_kprobe.c | 91 +++++++++++++++--
kernel/trace/trace_probe.h | 11 ++
kernel/trace/trace_uprobe.c | 86 ++++++++++++++--
samples/bpf/Makefile | 3 +
samples/bpf/bpf_load.c | 63 ++++++++++--
samples/bpf/bpf_load.h | 14 +++
samples/bpf/test_many_kprobe_user.c | 186 ++++++++++++++++++++++++++++++++++
tools/include/uapi/linux/perf_event.h | 14 +++
12 files changed, 662 insertions(+), 29 deletions(-)
create mode 100644 samples/bpf/test_many_kprobe_user.c

--
2.9.5

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