Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752825AbdLGKXo (ORCPT ); Thu, 7 Dec 2017 05:23:44 -0500 Received: from mail-wm0-f67.google.com ([74.125.82.67]:35434 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752506AbdLGKXm (ORCPT ); Thu, 7 Dec 2017 05:23:42 -0500 X-Google-Smtp-Source: AGs4zMakAe957vc+ce0U1NGX6kW5PqlkQb0wdeoigxS13liwe+6kuJdaRrnSSwGegNFvbO2ZHQQtZNlTCXJVYL8rMIg= MIME-Version: 1.0 In-Reply-To: <20171206224518.3598254-1-songliubraving@fb.com> References: <20171206224518.3598254-1-songliubraving@fb.com> From: Philippe Ombredanne Date: Thu, 7 Dec 2017 11:23:00 +0100 Message-ID: Subject: Re: [PATCH v5 0/6] enable creating [k,u]probe with perf_event_open To: Song Liu Cc: peterz@infradead.org, Steven Rostedt , Ingo Molnar , "David S. Miller" , netdev@vger.kernel.org, LKML , daniel@iogearbox.net, kernel-team@fb.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4051 Lines: 104 Song, On Wed, Dec 6, 2017 at 11:45 PM, Song Liu wrote: > Changes PATCH v4 to PATCH v5: > Remove PERF_PROBE_CONFIG_IS_RETPROBE from uapi, use PMU_FORMAT_ATTR > instead. > > 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 | 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 > > -- > 2.9.5 Thank you for using the SPDX ids! For this: Acked-by: Philippe Ombredanne