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samples/bpf: add tests for more perf event types

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$ trace_event

tests attaching BPF program to HW_CPU_CYCLES, SW_CPU_CLOCK, HW_CACHE_L1D and other events.
It runs 'dd' in the background while bpf program collects user and kernel
stack trace on counter overflow.
User space expects to see sys_read and sys_write in the kernel stack.

$ tracex6

tests reading of various perf counters from BPF program.

Both tests were refactored to increase coverage and be more accurate.

Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Teng Qin
2017-06-02 21:03:53 -07:00
committed by David S. Miller
parent f91840a32d
commit 41e9a8046c
4 changed files with 228 additions and 56 deletions
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73
samples/bpf/trace_event_user.c
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@@ -75,7 +75,10 @@ static void print_stack(struct key_t *key, __u64 count)
for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
print_addr(ip[i]);
}
printf("\n");
if (count < 6)
printf("\r");
else
printf("\n");
if (key->kernstack == -EEXIST && !warned) {
printf("stackmap collisions seen. Consider increasing size\n");
@@ -105,7 +108,7 @@ static void print_stacks(void)
bpf_map_delete_elem(fd, &next_key);
key = next_key;
}
printf("\n");
if (!sys_read_seen || !sys_write_seen) {
printf("BUG kernel stack doesn't contain sys_read() and sys_write()\n");
int_exit(0);
@@ -122,24 +125,29 @@ static void test_perf_event_all_cpu(struct perf_event_attr *attr)
{
int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
int *pmu_fd = malloc(nr_cpus * sizeof(int));
int i;
int i, error = 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);
if (pmu_fd[i] < 0) {
printf("sys_perf_event_open failed\n");
error = 1;
goto all_cpu_err;
}
assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0);
assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0) == 0);
assert(ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE) == 0);
}
system("dd if=/dev/zero of=/dev/null count=5000k");
system("dd if=/dev/zero of=/dev/null count=5000k status=none");
print_stacks();
all_cpu_err:
for (i--; i >= 0; i--)
for (i--; i >= 0; i--) {
ioctl(pmu_fd[i], PERF_EVENT_IOC_DISABLE);
close(pmu_fd[i]);
}
free(pmu_fd);
if (error)
int_exit(0);
}
static void test_perf_event_task(struct perf_event_attr *attr)
@@ -150,12 +158,13 @@ static void test_perf_event_task(struct perf_event_attr *attr)
pmu_fd = sys_perf_event_open(attr, 0, -1, -1, 0);
if (pmu_fd < 0) {
printf("sys_perf_event_open failed\n");
return;
int_exit(0);
}
assert(ioctl(pmu_fd, PERF_EVENT_IOC_SET_BPF, prog_fd[0]) == 0);
assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0) == 0);
system("dd if=/dev/zero of=/dev/null count=5000k");
assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE) == 0);
system("dd if=/dev/zero of=/dev/null count=5000k status=none");
print_stacks();
ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE);
close(pmu_fd);
}
@@ -175,11 +184,56 @@ static void test_bpf_perf_event(void)
.config = PERF_COUNT_SW_CPU_CLOCK,
.inherit = 1,
};
struct perf_event_attr attr_hw_cache_l1d = {
.sample_freq = SAMPLE_FREQ,
.freq = 1,
.type = PERF_TYPE_HW_CACHE,
.config =
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,
.freq = 1,
.type = PERF_TYPE_HW_CACHE,
.config =
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,
.freq = 1,
.type = PERF_TYPE_RAW,
/* Intel Instruction Retired */
.config = 0xc0,
.inherit = 1,
};
printf("Test HW_CPU_CYCLES\n");
test_perf_event_all_cpu(&attr_type_hw);
test_perf_event_task(&attr_type_hw);
printf("Test SW_CPU_CLOCK\n");
test_perf_event_all_cpu(&attr_type_sw);
test_perf_event_task(&attr_type_sw);
printf("Test HW_CACHE_L1D\n");
test_perf_event_all_cpu(&attr_hw_cache_l1d);
test_perf_event_task(&attr_hw_cache_l1d);
printf("Test HW_CACHE_BPU\n");
test_perf_event_all_cpu(&attr_hw_cache_branch_miss);
test_perf_event_task(&attr_hw_cache_branch_miss);
printf("Test Instruction Retired\n");
test_perf_event_all_cpu(&attr_type_raw);
test_perf_event_task(&attr_type_raw);
printf("*** PASS ***\n");
}
@@ -209,7 +263,6 @@ int main(int argc, char **argv)
return 0;
}
test_bpf_perf_event();
int_exit(0);
return 0;
}