Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753479AbbK3Hds (ORCPT ); Mon, 30 Nov 2015 02:33:48 -0500 Received: from szxga01-in.huawei.com ([58.251.152.64]:28725 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753315AbbK3Hco (ORCPT ); Mon, 30 Nov 2015 02:32:44 -0500 From: Wang Nan To: , , , CC: , , , Wang Nan , Arnaldo Carvalho de Melo , Brendan Gregg , "David S. Miller" Subject: [PATCH v3 09/13] perf tools: Introduce bpf-output event Date: Mon, 30 Nov 2015 07:32:09 +0000 Message-ID: <1448868733-225582-10-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1448868733-225582-1-git-send-email-wangnan0@huawei.com> References: <1448868733-225582-1-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=0001.0A090203.565BFB94.0074,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: 186a51c0a052243304d4e9aa18493dde Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4698 Lines: 126 Commit a43eec304259a6c637f4014a6d4767159b6a3aa3 (bpf: introduce bpf_perf_event_output() helper) add a helper to enable BPF program output data to perf ring buffer through a new type of perf event PERF_COUNT_SW_BPF_OUTPUT. This patch enable perf to create perf event of that type. Now perf user can use following cmdline to receive output data from BPF programs: # ./perf record -a -e evt=bpf-output/no-inherit/ \ -e ./test_bpf_output.c/maps:channel.event=evt/ ls / # ./perf script perf 12927 [004] 355971.129276: 0 evt=bpf-output/no-inherit/: ffffffff811ed5f1 sys_write perf 12927 [004] 355971.129279: 0 evt=bpf-output/no-inherit/: ffffffff811ed5f1 sys_write ... Test result: # cat ./test_bpf_output.c /************************ BEGIN **************************/ typedef int u32; typedef unsigned long long u64; enum bpf_map_type { BPF_MAP_TYPE_PERF_EVENT_ARRAY = 4, }; 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 (*bpf_ktime_get_ns)(void) = (void *)5; static int (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) = (void *)6; static int (*bpf_get_smp_processor_id)(void) = (void *)8; static int (*bpf_perf_event_output)(void *, struct bpf_map_def *, int, void *, unsigned long) = (void *)23; 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__, }; SEC("func_write=sys_write") int func_write(void *ctx) { struct { u64 ktime; int cpuid; } __attribute__((packed)) output_data; char error_data[] = "Error: failed to output\n"; output_data.cpuid = bpf_get_smp_processor_id(); output_data.ktime = bpf_ktime_get_ns(); int err = bpf_perf_event_output(ctx, &channel, bpf_get_smp_processor_id(), &output_data, sizeof(output_data)); if (err) bpf_trace_printk(error_data, sizeof(error_data)); return 0; } char _license[] SEC("license") = "GPL"; int _version SEC("version") = LINUX_VERSION_CODE; /************************ END ***************************/ # ./perf record -a -e evt=bpf-output/no-inherit/ \ -e ./test_bpf_output.c/maps:channel.event=evt/ ls / # ./perf script | grep ls ls 4085 [000] 2746114.230215: evt=bpf-output/no-inherit/: ffffffff811ed5f1 sys_write (/lib/modules/4.3.0-rc4+/build/vmlinux) ls 4085 [000] 2746114.230244: evt=bpf-output/no-inherit/: ffffffff811ed5f1 sys_write (/lib/modules/4.3.0-rc4+/build/vmlinux) Signed-off-by: Wang Nan Cc: Alexei Starovoitov Cc: Arnaldo Carvalho de Melo Cc: Brendan Gregg Cc: David S. Miller Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com --- tools/perf/util/evsel.c | 6 ++++++ tools/perf/util/parse-events.l | 1 + 2 files changed, 7 insertions(+) diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 32131fc..4dee8e3 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -224,6 +224,12 @@ struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx) if (evsel != NULL) perf_evsel__init(evsel, attr, idx); + if ((evsel->attr.type == PERF_TYPE_SOFTWARE) && + (evsel->attr.config == PERF_COUNT_SW_BPF_OUTPUT)) { + evsel->attr.sample_type |= PERF_SAMPLE_RAW; + evsel->attr.sample_period = 1; + } + return evsel; } diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l index 8bb3437..27d567f 100644 --- a/tools/perf/util/parse-events.l +++ b/tools/perf/util/parse-events.l @@ -249,6 +249,7 @@ cpu-migrations|migrations { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COU alignment-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_ALIGNMENT_FAULTS); } emulation-faults { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_EMULATION_FAULTS); } dummy { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_DUMMY); } +bpf-output { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_BPF_OUTPUT); } /* * We have to handle the kernel PMU event cycles-ct/cycles-t/mem-loads/mem-stores separately. -- 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/