From: Wang Nan Date: Wed, 24 Feb 2016 11:20:45 +0000 (+0000) Subject: perf script: Print bpf-output events in 'perf script' X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=30372f04c9dc159f99f1f09c61e5e0dbe4c91251;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git perf script: Print bpf-output events in 'perf script' This patch allows 'perf script' output messages from BPF program. For example, use test_bpf_output_3.c at the end of this commit message, # ./perf record -e bpf-output/no-inherit,name=evt/ \ -e ./test_bpf_output_3.c/map:channel.event=evt/ \ usleep 100000 # ./perf script usleep 4882 21384.532523: evt: ffffffff810e97d1 sys_nanosleep ([kernel.kallsyms]) BPF output: 0000: 52 61 69 73 65 20 61 20 Raise a 0008: 42 50 46 20 65 76 65 6e BPF even 0010: 74 21 00 00 t!.. BPF string: "Raise a BPF event!" usleep 4882 21384.632606: evt: ffffffff8105c609 kretprobe_trampoline_holder ([kernel.kallsyms BPF output: 0000: 52 61 69 73 65 20 61 20 Raise a 0008: 42 50 46 20 65 76 65 6e BPF even 0010: 74 21 00 00 t!.. BPF string: "Raise a BPF event!" Two samples from BPF output are printed by both binary and string format. If BPF program output something unprintable, string format is suppressed. /************************ 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!"; perf_event_output(ctx, &channel, get_smp_processor_id(), &output_str, sizeof(output_str)); return 0; } 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 Tested-by: Arnaldo Carvalho de Melo Cc: Brendan Gregg Cc: Jiri Olsa Cc: Li Zefan Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1456312845-111583-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index 8ff5ff0fe38c..ec4fbd410a4b 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -61,6 +61,7 @@ enum perf_output_field { PERF_OUTPUT_BRSTACKSYM = 1U << 16, PERF_OUTPUT_DATA_SRC = 1U << 17, PERF_OUTPUT_WEIGHT = 1U << 18, + PERF_OUTPUT_BPF_OUTPUT = 1U << 19, }; struct output_option { @@ -86,6 +87,7 @@ struct output_option { {.str = "brstacksym", .field = PERF_OUTPUT_BRSTACKSYM}, {.str = "data_src", .field = PERF_OUTPUT_DATA_SRC}, {.str = "weight", .field = PERF_OUTPUT_WEIGHT}, + {.str = "bpf-output", .field = PERF_OUTPUT_BPF_OUTPUT}, }; /* default set to maintain compatibility with current format */ @@ -106,7 +108,7 @@ static struct { PERF_OUTPUT_SYM | PERF_OUTPUT_DSO | PERF_OUTPUT_PERIOD, - .invalid_fields = PERF_OUTPUT_TRACE, + .invalid_fields = PERF_OUTPUT_TRACE | PERF_OUTPUT_BPF_OUTPUT, }, [PERF_TYPE_SOFTWARE] = { @@ -116,7 +118,7 @@ static struct { PERF_OUTPUT_CPU | PERF_OUTPUT_TIME | PERF_OUTPUT_EVNAME | PERF_OUTPUT_IP | PERF_OUTPUT_SYM | PERF_OUTPUT_DSO | - PERF_OUTPUT_PERIOD, + PERF_OUTPUT_PERIOD | PERF_OUTPUT_BPF_OUTPUT, .invalid_fields = PERF_OUTPUT_TRACE, }, @@ -126,7 +128,7 @@ static struct { .fields = PERF_OUTPUT_COMM | PERF_OUTPUT_TID | PERF_OUTPUT_CPU | PERF_OUTPUT_TIME | - PERF_OUTPUT_EVNAME | PERF_OUTPUT_TRACE, + PERF_OUTPUT_EVNAME | PERF_OUTPUT_TRACE }, [PERF_TYPE_RAW] = { @@ -139,7 +141,7 @@ static struct { PERF_OUTPUT_PERIOD | PERF_OUTPUT_ADDR | PERF_OUTPUT_DATA_SRC | PERF_OUTPUT_WEIGHT, - .invalid_fields = PERF_OUTPUT_TRACE, + .invalid_fields = PERF_OUTPUT_TRACE | PERF_OUTPUT_BPF_OUTPUT, }, [PERF_TYPE_BREAKPOINT] = { @@ -151,7 +153,7 @@ static struct { PERF_OUTPUT_SYM | PERF_OUTPUT_DSO | PERF_OUTPUT_PERIOD, - .invalid_fields = PERF_OUTPUT_TRACE, + .invalid_fields = PERF_OUTPUT_TRACE | PERF_OUTPUT_BPF_OUTPUT, }, }; @@ -624,6 +626,84 @@ static void print_sample_flags(u32 flags) printf(" %-4s ", str); } +struct printer_data { + int line_no; + bool hit_nul; + bool is_printable; +}; + +static void +print_sample_bpf_output_printer(enum binary_printer_ops op, + unsigned int val, + void *extra) +{ + unsigned char ch = (unsigned char)val; + struct printer_data *printer_data = extra; + + switch (op) { + case BINARY_PRINT_DATA_BEGIN: + printf("\n"); + break; + case BINARY_PRINT_LINE_BEGIN: + printf("%17s", !printer_data->line_no ? "BPF output:" : + " "); + break; + case BINARY_PRINT_ADDR: + printf(" %04x:", val); + break; + case BINARY_PRINT_NUM_DATA: + printf(" %02x", val); + break; + case BINARY_PRINT_NUM_PAD: + printf(" "); + break; + case BINARY_PRINT_SEP: + printf(" "); + break; + case BINARY_PRINT_CHAR_DATA: + if (printer_data->hit_nul && ch) + printer_data->is_printable = false; + + if (!isprint(ch)) { + printf("%c", '.'); + + if (!printer_data->is_printable) + break; + + if (ch == '\0') + printer_data->hit_nul = true; + else + printer_data->is_printable = false; + } else { + printf("%c", ch); + } + break; + case BINARY_PRINT_CHAR_PAD: + printf(" "); + break; + case BINARY_PRINT_LINE_END: + printf("\n"); + printer_data->line_no++; + break; + case BINARY_PRINT_DATA_END: + default: + break; + } +} + +static void print_sample_bpf_output(struct perf_sample *sample) +{ + unsigned int nr_bytes = sample->raw_size; + struct printer_data printer_data = {0, false, true}; + + print_binary(sample->raw_data, nr_bytes, 8, + print_sample_bpf_output_printer, &printer_data); + + if (printer_data.is_printable && printer_data.hit_nul) + printf("%17s \"%s\"\n", "BPF string:", + (char *)(sample->raw_data)); +} + struct perf_script { struct perf_tool tool; struct perf_session *session; @@ -731,6 +811,9 @@ static void process_event(struct perf_script *script, union perf_event *event, else if (PRINT_FIELD(BRSTACKSYM)) print_sample_brstacksym(event, sample, thread, attr); + if (perf_evsel__is_bpf_output(evsel) && PRINT_FIELD(BPF_OUTPUT)) + print_sample_bpf_output(sample); + printf("\n"); }