The bpf sample program trace_event is enhanced to use the new
helper to print out enabled/running time.
Signed-off-by: Yonghong Song <y...@fb.com>
---
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 41b6115..a77a583d 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 7bd827b..bf4f1b6 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 79eb529..50d2bcd 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -633,7 +633,8 @@ union bpf_attr {
FN(redirect_map), \
FN(sk_redirect_map), \
FN(sock_map_update), \
- 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 08e6f8c..1d3dcd4 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -73,6 +73,9 @@ 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
--
2.9.5
