selftests/bpf: extend the storage test to test per-cpu cgroup storage

This test extends the cgroup storage test to use per-cpu flavor
of the cgroup storage as well.

The test initializes a per-cpu cgroup storage to some non-zero initial
value (1000), and then simple bumps a per-cpu counter each time
the shared counter is atomically incremented. Then it reads all
per-cpu areas from the userspace side, and checks that the sum
of values adds to the expected sum.

Expected output:
  $ ./test_cgroup_storage
  test_cgroup_storage:PASS

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Roman Gushchin 2018-09-28 14:45:55 +00:00 committed by Daniel Borkmann
parent a3c6054f81
commit 919646d2a3

View File

@ -4,6 +4,7 @@
#include <linux/filter.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/sysinfo.h>
#include "bpf_rlimit.h"
#include "cgroup_helpers.h"
@ -15,6 +16,14 @@ char bpf_log_buf[BPF_LOG_BUF_SIZE];
int main(int argc, char **argv)
{
struct bpf_insn prog[] = {
BPF_LD_MAP_FD(BPF_REG_1, 0), /* percpu map fd */
BPF_MOV64_IMM(BPF_REG_2, 0), /* flags, not used */
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
BPF_FUNC_get_local_storage),
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 0x1),
BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_3, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0), /* map fd */
BPF_MOV64_IMM(BPF_REG_2, 0), /* flags, not used */
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
@ -28,9 +37,18 @@ int main(int argc, char **argv)
};
size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn);
int error = EXIT_FAILURE;
int map_fd, prog_fd, cgroup_fd;
int map_fd, percpu_map_fd, prog_fd, cgroup_fd;
struct bpf_cgroup_storage_key key;
unsigned long long value;
unsigned long long *percpu_value;
int cpu, nproc;
nproc = get_nprocs_conf();
percpu_value = malloc(sizeof(*percpu_value) * nproc);
if (!percpu_value) {
printf("Not enough memory for per-cpu area (%d cpus)\n", nproc);
goto err;
}
map_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_STORAGE, sizeof(key),
sizeof(value), 0, 0);
@ -39,7 +57,15 @@ int main(int argc, char **argv)
goto out;
}
prog[0].imm = map_fd;
percpu_map_fd = bpf_create_map(BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE,
sizeof(key), sizeof(value), 0, 0);
if (percpu_map_fd < 0) {
printf("Failed to create map: %s\n", strerror(errno));
goto out;
}
prog[0].imm = percpu_map_fd;
prog[7].imm = map_fd;
prog_fd = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
prog, insns_cnt, "GPL", 0,
bpf_log_buf, BPF_LOG_BUF_SIZE);
@ -77,7 +103,15 @@ int main(int argc, char **argv)
}
if (bpf_map_lookup_elem(map_fd, &key, &value)) {
printf("Failed to lookup cgroup storage\n");
printf("Failed to lookup cgroup storage 0\n");
goto err;
}
for (cpu = 0; cpu < nproc; cpu++)
percpu_value[cpu] = 1000;
if (bpf_map_update_elem(percpu_map_fd, &key, percpu_value, 0)) {
printf("Failed to update the data in the cgroup storage\n");
goto err;
}
@ -120,11 +154,31 @@ int main(int argc, char **argv)
goto err;
}
/* Check the final value of the counter in the percpu local storage */
for (cpu = 0; cpu < nproc; cpu++)
percpu_value[cpu] = 0;
if (bpf_map_lookup_elem(percpu_map_fd, &key, percpu_value)) {
printf("Failed to lookup the per-cpu cgroup storage\n");
goto err;
}
value = 0;
for (cpu = 0; cpu < nproc; cpu++)
value += percpu_value[cpu];
if (value != nproc * 1000 + 6) {
printf("Unexpected data in the per-cpu cgroup storage\n");
goto err;
}
error = 0;
printf("test_cgroup_storage:PASS\n");
err:
cleanup_cgroup_environment();
free(percpu_value);
out:
return error;