Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758444AbcDHPID (ORCPT ); Fri, 8 Apr 2016 11:08:03 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:46529 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758353AbcDHPIB (ORCPT ); Fri, 8 Apr 2016 11:08:01 -0400 From: Wang Nan To: CC: , , , , Arnaldo Carvalho de Melo , Jiri Olsa Subject: [PATCH 2/4] perf trace: Print content of bpf-output event Date: Fri, 8 Apr 2016 15:07:23 +0000 Message-ID: <1460128045-97310-3-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1460128045-97310-1-git-send-email-wangnan0@huawei.com> References: <1460128045-97310-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.193.248] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.5707C93B.0172,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 3f87fe0f7bff6576744a24570c5d5abf Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4349 Lines: 123 With this patch the contend of BPF output event is printed by 'perf trace'. For example: # ./perf trace -a --ev bpf-output/no-inherit,name=evt/ \ --ev ./test_bpf_trace.c/map:channel.event=evt/ \ usleep 100000 ... 1.787 ( 0.004 ms): usleep/3832 nanosleep(rqtp: 0x7ffc78b18980 ) ... 1.787 ( ): evt:Raise a BPF event!..) 1.788 ( ): perf_bpf_probe:func_begin:(ffffffff810e97d0)) ... 101.866 (87.038 ms): gmain/1654 poll(ufds: 0x7f57a80008c0, nfds: 2, timeout_msecs: 1000 ) ... 101.866 ( ): evt:Raise a BPF event!..) 101.867 ( ): perf_bpf_probe:func_end:(ffffffff810e97d0 <- ffffffff81796173)) 101.869 (100.087 ms): usleep/3832 ... [continued]: nanosleep()) = 0 ... (There is an extra ')' at the end of several lines. However, it is another problem, unrelated to this commit.) Where test_bpf_trace.c is: /************************ BEGIN **************************/ #include struct bpf_map_def { unsigned int type; unsigned int key_size; unsigned int value_size; unsigned int max_entries; }; #define SEC(NAME) __attribute__((section(NAME), used)) static u64 (*ktime_get_ns)(void) = (void *)BPF_FUNC_ktime_get_ns; static int (*trace_printk)(const char *fmt, int fmt_size, ...) = (void *)BPF_FUNC_trace_printk; static int (*get_smp_processor_id)(void) = (void *)BPF_FUNC_get_smp_processor_id; static int (*perf_event_output)(void *, struct bpf_map_def *, int, void *, unsigned long) = (void *)BPF_FUNC_perf_event_output; struct bpf_map_def SEC("maps") channel = { .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY, .key_size = sizeof(int), .value_size = sizeof(u32), .max_entries = __NR_CPUS__, }; static inline int __attribute__((always_inline)) func(void *ctx, int type) { char output_str[] = "Raise a BPF event!"; char err_str[] = "BAD %d\n"; int err; err = perf_event_output(ctx, &channel, get_smp_processor_id(), &output_str, sizeof(output_str)); if (err) trace_printk(err_str, sizeof(err_str), err); return 1; } SEC("func_begin=sys_nanosleep") int func_begin(void *ctx) {return func(ctx, 1);} SEC("func_end=sys_nanosleep%return") int func_end(void *ctx) { return func(ctx, 2);} char _license[] SEC("license") = "GPL"; int _version SEC("version") = LINUX_VERSION_CODE; /************************* END ***************************/ Signed-off-by: Wang Nan Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Li Zefan Cc: pi3orama@163.com --- tools/perf/builtin-trace.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 6fbed86..fb8257f 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2680,11 +2680,15 @@ out_enomem: goto out; } -static int validate_evlist(struct perf_evlist *evlist) +static int validate_evlist(struct perf_evlist *evlist, bool *has_bpf_output) { struct perf_evsel *evsel; evlist__for_each(evlist, evsel) { + if (perf_evsel__is_bpf_output(evsel)) { + *has_bpf_output = true; + continue; + } if (evsel->attr.type != PERF_TYPE_TRACEPOINT) return -EINVAL; } @@ -3268,6 +3272,7 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused) const char * const trace_subcommands[] = { "record", NULL }; int err; char bf[BUFSIZ]; + bool has_bpf_output = false; signal(SIGSEGV, sighandler_dump_stack); signal(SIGFPE, sighandler_dump_stack); @@ -3284,12 +3289,12 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused) argc = parse_options_subcommand(argc, argv, trace_options, trace_subcommands, trace_usage, PARSE_OPT_STOP_AT_NON_OPTION); - if (validate_evlist(trace.evlist)) { - pr_err("Only support tracepoint events!\n"); + if (validate_evlist(trace.evlist, &has_bpf_output)) { + pr_err("Only support tracepoint and bpf-output events!\n"); return -EINVAL; } - if (trace.trace_pgfaults) { + if (trace.trace_pgfaults || has_bpf_output) { trace.opts.sample_address = true; trace.opts.sample_time = true; } -- 1.8.3.4