[PATCH bpf-next v4 2/2] bpf: Add selftests for bpf_perf_event_output
From: allanzhang
Date: Tue Jun 25 2019 - 13:27:31 EST
Software event output is only enabled by a few prog types.
This test is to ensure that all supported types are enbled for
bpf_perf_event_output sucessfully.
v4:
* Reformating log message
v3:
* Reformating log message
v2:
* Reformating log message
Signed-off-by: allanzhang <allanzhang@xxxxxxxxxx>
---
tools/testing/selftests/bpf/test_verifier.c | 33 ++++++-
.../selftests/bpf/verifier/event_output.c | 94 +++++++++++++++++++
2 files changed, 126 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/verifier/event_output.c
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index c5514daf8865..901a188e1eea 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -50,7 +50,7 @@
#define MAX_INSNS BPF_MAXINSNS
#define MAX_TEST_INSNS 1000000
#define MAX_FIXUPS 8
-#define MAX_NR_MAPS 18
+#define MAX_NR_MAPS 19
#define MAX_TEST_RUNS 8
#define POINTER_VALUE 0xcafe4all
#define TEST_DATA_LEN 64
@@ -84,6 +84,7 @@ struct bpf_test {
int fixup_map_array_wo[MAX_FIXUPS];
int fixup_map_array_small[MAX_FIXUPS];
int fixup_sk_storage_map[MAX_FIXUPS];
+ int fixup_map_event_output[MAX_FIXUPS];
const char *errstr;
const char *errstr_unpriv;
uint32_t retval, retval_unpriv, insn_processed;
@@ -604,6 +605,28 @@ static int create_sk_storage_map(void)
return fd;
}
+static int create_event_output_map(void)
+{
+ struct bpf_create_map_attr attr = {
+ .name = "test_map",
+ .map_type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+ .key_size = 4,
+ .value_size = 4,
+ .max_entries = 1,
+ };
+ int fd, btf_fd;
+
+ btf_fd = load_btf();
+ if (btf_fd < 0)
+ return -1;
+ attr.btf_fd = btf_fd;
+ fd = bpf_create_map_xattr(&attr);
+ close(attr.btf_fd);
+ if (fd < 0)
+ printf("Failed to create event_output\n");
+ return fd;
+}
+
static char bpf_vlog[UINT_MAX >> 8];
static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
@@ -627,6 +650,7 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
int *fixup_map_array_wo = test->fixup_map_array_wo;
int *fixup_map_array_small = test->fixup_map_array_small;
int *fixup_sk_storage_map = test->fixup_sk_storage_map;
+ int *fixup_map_event_output = test->fixup_map_event_output;
if (test->fill_helper) {
test->fill_insns = calloc(MAX_TEST_INSNS, sizeof(struct bpf_insn));
@@ -788,6 +812,13 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
fixup_sk_storage_map++;
} while (*fixup_sk_storage_map);
}
+ if (*fixup_map_event_output) {
+ map_fds[18] = create_event_output_map();
+ do {
+ prog[*fixup_map_event_output].imm = map_fds[18];
+ fixup_map_event_output++;
+ } while (*fixup_map_event_output);
+ }
}
static int set_admin(bool admin)
diff --git a/tools/testing/selftests/bpf/verifier/event_output.c b/tools/testing/selftests/bpf/verifier/event_output.c
new file mode 100644
index 000000000000..b25eabcfaa56
--- /dev/null
+++ b/tools/testing/selftests/bpf/verifier/event_output.c
@@ -0,0 +1,94 @@
+/* instructions used to output a skb based software event, produced
+ * from code snippet:
+struct TMP {
+ uint64_t tmp;
+} tt;
+tt.tmp = 5;
+bpf_perf_event_output(skb, &connection_tracking_event_map, 0,
+ &tt, sizeof(tt));
+return 1;
+
+the bpf assembly from llvm is:
+ 0: b7 02 00 00 05 00 00 00 r2 = 5
+ 1: 7b 2a f8 ff 00 00 00 00 *(u64 *)(r10 - 8) = r2
+ 2: bf a4 00 00 00 00 00 00 r4 = r10
+ 3: 07 04 00 00 f8 ff ff ff r4 += -8
+ 4: 18 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r2 = 0ll
+ 6: b7 03 00 00 00 00 00 00 r3 = 0
+ 7: b7 05 00 00 08 00 00 00 r5 = 8
+ 8: 85 00 00 00 19 00 00 00 call 25
+ 9: b7 00 00 00 01 00 00 00 r0 = 1
+ 10: 95 00 00 00 00 00 00 00 exit
+
+ The reason I put the code here instead of fill_helpers is that map fixup is
+ against the insns, instead of filled prog.
+*/
+
+#define __PERF_EVENT_INSNS__ \
+ BPF_MOV64_IMM(BPF_REG_2, 5), \
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -8), \
+ BPF_MOV64_REG(BPF_REG_4, BPF_REG_10), \
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8), \
+ BPF_LD_MAP_FD(BPF_REG_2, 0), \
+ BPF_MOV64_IMM(BPF_REG_3, 0), \
+ BPF_MOV64_IMM(BPF_REG_5, 8), \
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, \
+ BPF_FUNC_perf_event_output), \
+ BPF_MOV64_IMM(BPF_REG_0, 1), \
+ BPF_EXIT_INSN(),
+{
+ "perfevent for sockops",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SOCK_OPS,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for tc",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SCHED_CLS,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for lwt out",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_LWT_OUT,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for xdp",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_XDP,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for socket filter",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SOCKET_FILTER,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for sk_skb",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_SK_SKB,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
+{
+ "perfevent for cgroup skb",
+ .insns = { __PERF_EVENT_INSNS__ },
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ .fixup_map_event_output = { 4 },
+ .result = ACCEPT,
+ .retval = 1,
+},
--
2.22.0.410.gd8fdbe21b5-goog