[PATCH v5 0/6] enable creating [k,u]probe with perf_event_open
- Date: Wed, 6 Dec 2017 14:45:10 -0800
- From: Song Liu <songliubraving@xxxxxx>
- Subject: [PATCH v5 0/6] enable creating [k,u]probe with perf_event_open
Changes PATCH v4 to PATCH v5:
Remove PERF_PROBE_CONFIG_IS_RETPROBE from uapi, use PMU_FORMAT_ATTR
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().
Changes PATCH v2 to PATCH v3:
Remove fixed type PERF_TYPE_KPROBE and PERF_TYPE_UPROBE, use dynamic
Update userspace (samples/bpf, bcc) to look up type from sysfs.
Change License info in test_many_kprobe_user.c as Philippe Ombredanne
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
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
perf_event_open.2: add type kprobe and uprobe
bcc: Try use new API to create [k,u]probe with perf_event_open
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 | 4 +
kernel/events/core.c | 131 +++++++++++++++++++++++-
kernel/trace/trace_event_perf.c | 102 +++++++++++++++++++
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 | 66 ++++++++++--
samples/bpf/bpf_load.h | 14 +++
samples/bpf/test_many_kprobe_user.c | 186 ++++++++++++++++++++++++++++++++++
tools/include/uapi/linux/perf_event.h | 4 +
12 files changed, 677 insertions(+), 29 deletions(-)
create mode 100644 samples/bpf/test_many_kprobe_user.c