[PATCH v9 bpf-next 14/14] bpf: update xdp_adjust_tail selftest to include multi-buffer

Lorenzo Bianconi
2021-06-14T12:52:12Z

From: Eelco Chaudron <echaudro@redhat.com>

This change adds test cases for the multi-buffer scenarios when shrinking
and growing.

Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
.../bpf/prog_tests/xdp_adjust_tail.c | 105 ++++++++++++++++++
.../bpf/progs/test_xdp_adjust_tail_grow.c | 10 +-
.../bpf/progs/test_xdp_adjust_tail_shrink.c | 32 +++++-
3 files changed, 140 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c b/tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c
index d5c98f2cb12f..b936beaba797 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_adjust_tail.c
@@ -130,6 +130,107 @@ void test_xdp_adjust_tail_grow2(void)
bpf_object__close(obj);
}

+void test_xdp_adjust_mb_tail_shrink(void)
+{
+ const char *file = "./test_xdp_adjust_tail_shrink.o";
+ __u32 duration, retval, size, exp_size;
+ struct bpf_object *obj;
+ static char buf[9000];
+ int err, prog_fd;
+
+ /* For the individual test cases, the first byte in the packet
+ * indicates which test will be run.
+ */
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ /* Test case removing 10 bytes from last frag, NOT freeing it */
+ buf[0] = 0;
+ exp_size = sizeof(buf) - 10;
+ err = bpf_prog_test_run(prog_fd, 1, buf, sizeof(buf),
+ buf, &size, &retval, &duration);
+
+ CHECK(err || retval != XDP_TX || size != exp_size,
+ "9k-10b", "err %d errno %d retval %d[%d] size %d[%u]\n",
+ err, errno, retval, XDP_TX, size, exp_size);
+
+ /* Test case removing one of two pages, assuming 4K pages */
+ buf[0] = 1;
+ exp_size = sizeof(buf) - 4100;
+ err = bpf_prog_test_run(prog_fd, 1, buf, sizeof(buf),
+ buf, &size, &retval, &duration);
+
+ CHECK(err || retval != XDP_TX || size != exp_size,
+ "9k-1p", "err %d errno %d retval %d[%d] size %d[%u]\n",
+ err, errno, retval, XDP_TX, size, exp_size);
+
+ /* Test case removing two pages resulting in a non mb xdp_buff */
+ buf[0] = 2;
+ exp_size = sizeof(buf) - 8200;
+ err = bpf_prog_test_run(prog_fd, 1, buf, sizeof(buf),
+ buf, &size, &retval, &duration);
+
+ CHECK(err || retval != XDP_TX || size != exp_size,
+ "9k-2p", "err %d errno %d retval %d[%d] size %d[%u]\n",
+ err, errno, retval, XDP_TX, size, exp_size);
+
+ bpf_object__close(obj);
+}
+
+void test_xdp_adjust_mb_tail_grow(void)
+{
+ const char *file = "./test_xdp_adjust_tail_grow.o";
+ __u32 duration, retval, size, exp_size;
+ static char buf[16384];
+ struct bpf_object *obj;
+ int err, i, prog_fd;
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj, &prog_fd);
+ if (CHECK_FAIL(err))
+ return;
+
+ /* Test case add 10 bytes to last frag */
+ memset(buf, 1, sizeof(buf));
+ size = 9000;
+ exp_size = size + 10;
+ err = bpf_prog_test_run(prog_fd, 1, buf, size,
+ buf, &size, &retval, &duration);
+
+ CHECK(err || retval != XDP_TX || size != exp_size,
+ "9k+10b", "err %d retval %d[%d] size %d[%u]\n",
+ err, retval, XDP_TX, size, exp_size);
+
+ for (i = 0; i < 9000; i++)
+ CHECK(buf[i] != 1, "9k+10b-old",
+ "Old data not all ok, offset %i is failing [%u]!\n",
+ i, buf[i]);
+
+ for (i = 9000; i < 9010; i++)
+ CHECK(buf[i] != 0, "9k+10b-new",
+ "New data not all ok, offset %i is failing [%u]!\n",
+ i, buf[i]);
+
+ for (i = 9010; i < sizeof(buf); i++)
+ CHECK(buf[i] != 1, "9k+10b-untouched",
+ "Unused data not all ok, offset %i is failing [%u]!\n",
+ i, buf[i]);
+
+ /* Test a too large grow */
+ memset(buf, 1, sizeof(buf));
+ size = 9001;
+ exp_size = size;
+ err = bpf_prog_test_run(prog_fd, 1, buf, size,
+ buf, &size, &retval, &duration);
+
+ CHECK(err || retval != XDP_DROP || size != exp_size,
+ "9k+10b", "err %d retval %d[%d] size %d[%u]\n",
+ err, retval, XDP_TX, size, exp_size);
+
+ bpf_object__close(obj);
+}
+
void test_xdp_adjust_tail(void)
{
if (test__start_subtest("xdp_adjust_tail_shrink"))
@@ -138,4 +239,8 @@ void test_xdp_adjust_tail(void)
test_xdp_adjust_tail_grow();
if (test__start_subtest("xdp_adjust_tail_grow2"))
test_xdp_adjust_tail_grow2();
+ if (test__start_subtest("xdp_adjust_mb_tail_shrink"))
+ test_xdp_adjust_mb_tail_shrink();
+ if (test__start_subtest("xdp_adjust_mb_tail_grow"))
+ test_xdp_adjust_mb_tail_grow();
}
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_grow.c b/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_grow.c
index 3d66599eee2e..3d43defb0e00 100644
--- a/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_grow.c
+++ b/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_grow.c
@@ -7,11 +7,10 @@ int _xdp_adjust_tail_grow(struct xdp_md *xdp)
{
void *data_end = (void *)(long)xdp->data_end;
void *data = (void *)(long)xdp->data;
- unsigned int data_len;
+ int data_len = bpf_xdp_get_buff_len(xdp);
int offset = 0;

/* Data length determine test case */
- data_len = data_end - data;

if (data_len == 54) { /* sizeof(pkt_v4) */
offset = 4096; /* test too large offset */
@@ -20,7 +19,12 @@ int _xdp_adjust_tail_grow(struct xdp_md *xdp)
} else if (data_len == 64) {
offset = 128;
} else if (data_len == 128) {
- offset = 4096 - 256 - 320 - data_len; /* Max tail grow 3520 */
+ /* Max tail grow 3520 */
+ offset = 4096 - 256 - 320 - data_len;
+ } else if (data_len == 9000) {
+ offset = 10;
+ } else if (data_len == 9001) {
+ offset = 4096;
} else {
return XDP_ABORTED; /* No matching test */
}
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_shrink.c b/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_shrink.c
index 22065a9cfb25..64177597ac29 100644
--- a/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_shrink.c
+++ b/tools/testing/selftests/bpf/progs/test_xdp_adjust_tail_shrink.c
@@ -14,14 +14,38 @@ int _version SEC("version") = 1;
SEC("xdp_adjust_tail_shrink")
int _xdp_adjust_tail_shrink(struct xdp_md *xdp)
{
- void *data_end = (void *)(long)xdp->data_end;
- void *data = (void *)(long)xdp->data;
+ __u8 *data_end = (void *)(long)xdp->data_end;
+ __u8 *data = (void *)(long)xdp->data;
int offset = 0;

- if (data_end - data == 54) /* sizeof(pkt_v4) */
+ switch (bpf_xdp_get_buff_len(xdp)) {
+ case 54:
+ /* sizeof(pkt_v4) */
offset = 256; /* shrink too much */
- else
+ break;
+ case 9000:
+ /* Multi-buffer test cases */
+ if (data + 1 > data_end)
+ return XDP_DROP;
+
+ switch (data[0]) {
+ case 0:
+ offset = 10;
+ break;
+ case 1:
+ offset = 4100;
+ break;
+ case 2:
+ offset = 8200;
+ break;
+ default:
+ return XDP_DROP;
+ }
+ break;
+ default:
offset = 20;
+ break;
+ }
if (bpf_xdp_adjust_tail(xdp, 0 - offset))
return XDP_DROP;
return XDP_TX;
--
2.31.1