From 81b9cf8028a17bdbdaa0da80b735b32150d4e89e Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 5 Oct 2017 09:19:23 -0700 Subject: [PATCH] bpf: add a test case for helper bpf_perf_prog_read_value The bpf sample program trace_event is enhanced to use the new helper to print out enabled/running time. Signed-off-by: Yonghong Song Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- samples/bpf/trace_event_kern.c | 10 ++++++++++ samples/bpf/trace_event_user.c | 13 ++++++++----- tools/include/uapi/linux/bpf.h | 3 ++- tools/testing/selftests/bpf/bpf_helpers.h | 3 +++ 4 files changed, 23 insertions(+), 6 deletions(-) diff --git a/samples/bpf/trace_event_kern.c b/samples/bpf/trace_event_kern.c index 41b6115a32eb..a77a583d94d4 100644 --- a/samples/bpf/trace_event_kern.c +++ b/samples/bpf/trace_event_kern.c @@ -37,10 +37,14 @@ struct bpf_map_def SEC("maps") stackmap = { SEC("perf_event") int bpf_prog1(struct bpf_perf_event_data *ctx) { + char time_fmt1[] = "Time Enabled: %llu, Time Running: %llu"; + char time_fmt2[] = "Get Time Failed, ErrCode: %d"; char fmt[] = "CPU-%d period %lld ip %llx"; u32 cpu = bpf_get_smp_processor_id(); + struct bpf_perf_event_value value_buf; struct key_t key; u64 *val, one = 1; + int ret; if (ctx->sample_period < 10000) /* ignore warmup */ @@ -54,6 +58,12 @@ int bpf_prog1(struct bpf_perf_event_data *ctx) return 0; } + ret = bpf_perf_prog_read_value(ctx, (void *)&value_buf, sizeof(struct bpf_perf_event_value)); + if (!ret) + bpf_trace_printk(time_fmt1, sizeof(time_fmt1), value_buf.enabled, value_buf.running); + else + bpf_trace_printk(time_fmt2, sizeof(time_fmt2), ret); + val = bpf_map_lookup_elem(&counts, &key); if (val) (*val)++; diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c index 7bd827b84a67..bf4f1b6d9a52 100644 --- a/samples/bpf/trace_event_user.c +++ b/samples/bpf/trace_event_user.c @@ -127,6 +127,9 @@ static void test_perf_event_all_cpu(struct perf_event_attr *attr) int *pmu_fd = malloc(nr_cpus * sizeof(int)); int i, error = 0; + /* system wide perf event, no need to inherit */ + attr->inherit = 0; + /* open perf_event on all cpus */ for (i = 0; i < nr_cpus; i++) { pmu_fd[i] = sys_perf_event_open(attr, -1, i, -1, 0); @@ -154,6 +157,11 @@ static void test_perf_event_task(struct perf_event_attr *attr) { int pmu_fd; + /* per task perf event, enable inherit so the "dd ..." command can be traced properly. + * Enabling inherit will cause bpf_perf_prog_read_time helper failure. + */ + attr->inherit = 1; + /* open task bound event */ pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0); if (pmu_fd < 0) { @@ -175,14 +183,12 @@ static void test_bpf_perf_event(void) .freq = 1, .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES, - .inherit = 1, }; struct perf_event_attr attr_type_sw = { .sample_freq = SAMPLE_FREQ, .freq = 1, .type = PERF_TYPE_SOFTWARE, .config = PERF_COUNT_SW_CPU_CLOCK, - .inherit = 1, }; struct perf_event_attr attr_hw_cache_l1d = { .sample_freq = SAMPLE_FREQ, @@ -192,7 +198,6 @@ static void test_bpf_perf_event(void) PERF_COUNT_HW_CACHE_L1D | (PERF_COUNT_HW_CACHE_OP_READ << 8) | (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16), - .inherit = 1, }; struct perf_event_attr attr_hw_cache_branch_miss = { .sample_freq = SAMPLE_FREQ, @@ -202,7 +207,6 @@ static void test_bpf_perf_event(void) PERF_COUNT_HW_CACHE_BPU | (PERF_COUNT_HW_CACHE_OP_READ << 8) | (PERF_COUNT_HW_CACHE_RESULT_MISS << 16), - .inherit = 1, }; struct perf_event_attr attr_type_raw = { .sample_freq = SAMPLE_FREQ, @@ -210,7 +214,6 @@ static void test_bpf_perf_event(void) .type = PERF_TYPE_RAW, /* Intel Instruction Retired */ .config = 0xc0, - .inherit = 1, }; printf("Test HW_CPU_CYCLES\n"); diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index cdf6c4f50b0f..0894fd20b12b 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -698,7 +698,8 @@ union bpf_attr { FN(sk_redirect_map), \ FN(sock_map_update), \ FN(xdp_adjust_meta), \ - FN(perf_event_read_value), + FN(perf_event_read_value), \ + FN(perf_prog_read_value), /* integer value in 'imm' field of BPF_CALL instruction selects which helper * function eBPF program intends to call diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h index c15ca83dbbd9..e25dbf6038cf 100644 --- a/tools/testing/selftests/bpf/bpf_helpers.h +++ b/tools/testing/selftests/bpf/bpf_helpers.h @@ -75,6 +75,9 @@ static int (*bpf_sock_map_update)(void *map, void *key, void *value, static int (*bpf_perf_event_read_value)(void *map, unsigned long long flags, void *buf, unsigned int buf_size) = (void *) BPF_FUNC_perf_event_read_value; +static int (*bpf_perf_prog_read_value)(void *ctx, void *buf, + unsigned int buf_size) = + (void *) BPF_FUNC_perf_prog_read_value; /* llvm builtin functions that eBPF C program may use to -- 2.30.2