Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753571AbbFZOYm (ORCPT ); Fri, 26 Jun 2015 10:24:42 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:45201 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752721AbbFZORA (ORCPT ); Fri, 26 Jun 2015 10:17:00 -0400 From: Wang Nan To: , , , , , , , , , , CC: , , , , Subject: [RFC PATCH v9 33/50] perf record: Probe at kprobe points Date: Fri, 26 Jun 2015 14:15:38 +0000 Message-ID: <1435328155-87115-34-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1435328155-87115-1-git-send-email-wangnan0@huawei.com> References: <1435328155-87115-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.210] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3915 Lines: 142 In this patch, kprobe points are created using add_perf_probe_events. Since all events are already grouped together in an array, calling add_perf_probe_events() once creates all of them. probe_conf.max_probes is set to MAX_PROBES to support glob matching. Signed-off-by: Wang Nan --- tools/perf/builtin-record.c | 18 ++++++++++++++++- tools/perf/util/bpf-loader.c | 48 ++++++++++++++++++++++++++++++++++++++++++++ tools/perf/util/bpf-loader.h | 4 ++++ 3 files changed, 69 insertions(+), 1 deletion(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index de165a1..28ceae8 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -29,6 +29,7 @@ #include "util/data.h" #include "util/auxtrace.h" #include "util/parse-branch-options.h" +#include "util/bpf-loader.h" #include #include @@ -1109,7 +1110,21 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused) if (err) return err; - err = -ENOMEM; + /* + * bpf__probe must be called before symbol__init() because we + * need init_symbol_maps. If called after symbol__init, + * symbol_conf.sort_by_name won't take effect. + * + * bpf__unprobe() is safe even if bpf__probe() failed, and it + * also calls symbol__init. Therefore, goto out_symbol_exit + * is safe when probe failed. + */ + err = bpf__probe(); + if (err) { + pr_err("Probing at events in BPF object failed.\n"); + pr_err("Try perf probe -d '*' to remove existing probe events.\n"); + goto out_symbol_exit; + } symbol__init(NULL); @@ -1170,6 +1185,7 @@ out_symbol_exit: perf_evlist__delete(rec->evlist); symbol__exit(); auxtrace_record__free(rec->itr); + bpf__unprobe(); return err; } diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index 1efb4a6..21f2264 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -193,3 +193,51 @@ void bpf__clear(void) bpf_object__for_each(obj, tmp) bpf_object__close(obj); } + +static bool is_probing; + +int bpf__unprobe(void) +{ + struct strfilter *delfilter; + int ret; + + if (!is_probing) + return 0; + + delfilter = strfilter__new(PERF_BPF_PROBE_GROUP ":*", NULL); + if (!delfilter) { + pr_err("Failed to create delfilter when unprobing\n"); + return -ENOMEM; + } + + ret = del_perf_probe_events(delfilter); + strfilter__delete(delfilter); + if (ret < 0 && is_probing) + pr_err("Error: failed to delete events: %s\n", + strerror(-ret)); + else + is_probing = false; + return ret < 0 ? ret : 0; +} + +int bpf__probe(void) +{ + int err; + + if (nr_probe_events <= 0) + return 0; + + probe_conf.max_probes = MAX_PROBES; + /* Let add_perf_probe_events keeps probe_trace_event */ + err = add_perf_probe_events(probe_event_array, + nr_probe_events, + false); + + /* add_perf_probe_events return negative when fail */ + if (err < 0) + pr_err("bpf probe: failed to probe events\n"); + else + is_probing = true; + + return err < 0 ? err : 0; +} diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h index 5a3c954..374aec0 100644 --- a/tools/perf/util/bpf-loader.h +++ b/tools/perf/util/bpf-loader.h @@ -12,6 +12,8 @@ #ifdef HAVE_LIBBPF_SUPPORT int bpf__prepare_load(const char *filename, bool source); +int bpf__probe(void); +int bpf__unprobe(void); void bpf__clear(void); #else @@ -22,6 +24,8 @@ static inline int bpf__prepare_load(const char *filename __maybe_unused, return -1; } +static inline int bpf__probe(void) { return 0; } +static inline int bpf__unprobe(void) { return 0; } static inline void bpf__clear(void) { } #endif #endif -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/