@@ -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;
}
@@ -124,6 +124,10 @@ struct event_symbol event_symbols_sw[PERF_COUNT_SW_MAX] = {
.symbol = "dummy",
.alias = "",
},
+ [PERF_COUNT_SW_BPF_OUTPUT] = {
+ .symbol = "bpf-output",
+ .alias = "",
+ },
};
#define __PERF_EVENT_FIELD(config, name) \
@@ -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.
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 <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com --- tools/perf/util/evsel.c | 6 ++++++ tools/perf/util/parse-events.c | 4 ++++ tools/perf/util/parse-events.l | 1 + 3 files changed, 11 insertions(+) -- 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/