2023-03-29 18:12:26

by Kal Cutter Conley

Subject: [PATCH bpf-next v2 07/10] selftests: xsk: Add test UNALIGNED_INV_DESC_4K1_FRAME_SIZE

Add unaligned descriptor test for frame size of 4001. Using an odd frame
size ensures that the end of the UMEM is not near a page boundary. This
allows testing descriptors that staddle the end of the UMEM but not a
page.

This test used to fail without the previous commit ("xsk: Add check for
unaligned descriptors that overrun UMEM").

Signed-off-by: Kal Conley <[email protected]>
---
tools/testing/selftests/bpf/xskxceiver.c | 25 ++++++++++++++++++++++++
tools/testing/selftests/bpf/xskxceiver.h | 1 +
2 files changed, 26 insertions(+)

diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
index 1a4bdd5aa78c..9b9efd0e0a4c 100644
--- a/tools/testing/selftests/bpf/xskxceiver.c
+++ b/tools/testing/selftests/bpf/xskxceiver.c
@@ -69,6 +69,7 @@
*/

#define _GNU_SOURCE
+#include <assert.h>
#include <fcntl.h>
#include <errno.h>
#include <getopt.h>
@@ -1876,6 +1877,30 @@ static void run_pkt_test(struct test_spec *test, enum test_mode mode, enum test_
test->ifobj_rx->umem->unaligned_mode = true;
testapp_invalid_desc(test);
break;
+ case TEST_TYPE_UNALIGNED_INV_DESC_4K1_FRAME:
+ if (!hugepages_present(test->ifobj_tx)) {
+ ksft_test_result_skip("No 2M huge pages present.\n");
+ return;
+ }
+ test_spec_set_name(test, "UNALIGNED_INV_DESC_4K1_FRAME_SIZE");
+ /* Odd frame size so the UMEM doesn't end near a page boundary. */
+ test->ifobj_tx->umem->frame_size = 4001;
+ test->ifobj_rx->umem->frame_size = 4001;
+ test->ifobj_tx->umem->unaligned_mode = true;
+ test->ifobj_rx->umem->unaligned_mode = true;
+ /* This test exists to test descriptors that staddle the end of
+ * the UMEM but not a page.
+ */
+ {
+ u64 umem_size = test->ifobj_tx->umem->num_frames *
+ test->ifobj_tx->umem->frame_size;
+ u64 page_size = sysconf(_SC_PAGESIZE);
+
+ assert(umem_size % page_size > PKT_SIZE);
+ assert(umem_size % page_size < page_size - PKT_SIZE);
+ }
+ testapp_invalid_desc(test);
+ break;
case TEST_TYPE_UNALIGNED:
if (!testapp_unaligned(test))
return;
diff --git a/tools/testing/selftests/bpf/xskxceiver.h b/tools/testing/selftests/bpf/xskxceiver.h
index cc24ab72f3ff..919327807a4e 100644
--- a/tools/testing/selftests/bpf/xskxceiver.h
+++ b/tools/testing/selftests/bpf/xskxceiver.h
@@ -78,6 +78,7 @@ enum test_type {
TEST_TYPE_ALIGNED_INV_DESC,
TEST_TYPE_ALIGNED_INV_DESC_2K_FRAME,
TEST_TYPE_UNALIGNED_INV_DESC,
+ TEST_TYPE_UNALIGNED_INV_DESC_4K1_FRAME,
TEST_TYPE_HEADROOM,
TEST_TYPE_TEARDOWN,
TEST_TYPE_BIDI,
--
2.39.2

2023-04-03 12:28:14

by Magnus Karlsson

Subject: Re: [PATCH bpf-next v2 07/10] selftests: xsk: Add test UNALIGNED_INV_DESC_4K1_FRAME_SIZE

On Wed, 29 Mar 2023 at 20:12, Kal Conley <[email protected]> wrote:
>
> Add unaligned descriptor test for frame size of 4001. Using an odd frame
> size ensures that the end of the UMEM is not near a page boundary. This
> allows testing descriptors that staddle the end of the UMEM but not a

nit: straddle

> page.
>
> This test used to fail without the previous commit ("xsk: Add check for
> unaligned descriptors that overrun UMEM").
>
> Signed-off-by: Kal Conley <[email protected]>
> ---
> tools/testing/selftests/bpf/xskxceiver.c | 25 ++++++++++++++++++++++++
> tools/testing/selftests/bpf/xskxceiver.h | 1 +
> 2 files changed, 26 insertions(+)
>
> diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c
> index 1a4bdd5aa78c..9b9efd0e0a4c 100644
> --- a/tools/testing/selftests/bpf/xskxceiver.c
> +++ b/tools/testing/selftests/bpf/xskxceiver.c
> @@ -69,6 +69,7 @@
> */
>
> #define _GNU_SOURCE
> +#include <assert.h>
> #include <fcntl.h>
> #include <errno.h>
> #include <getopt.h>
> @@ -1876,6 +1877,30 @@ static void run_pkt_test(struct test_spec *test, enum test_mode mode, enum test_
> test->ifobj_rx->umem->unaligned_mode = true;
> testapp_invalid_desc(test);
> break;
> + case TEST_TYPE_UNALIGNED_INV_DESC_4K1_FRAME:
> + if (!hugepages_present(test->ifobj_tx)) {
> + ksft_test_result_skip("No 2M huge pages present.\n");
> + return;
> + }
> + test_spec_set_name(test, "UNALIGNED_INV_DESC_4K1_FRAME_SIZE");
> + /* Odd frame size so the UMEM doesn't end near a page boundary. */
> + test->ifobj_tx->umem->frame_size = 4001;
> + test->ifobj_rx->umem->frame_size = 4001;
> + test->ifobj_tx->umem->unaligned_mode = true;
> + test->ifobj_rx->umem->unaligned_mode = true;
> + /* This test exists to test descriptors that staddle the end of

nit: straddle

> + * the UMEM but not a page.
> + */
> + {
> + u64 umem_size = test->ifobj_tx->umem->num_frames *
> + test->ifobj_tx->umem->frame_size;
> + u64 page_size = sysconf(_SC_PAGESIZE);
> +
> + assert(umem_size % page_size > PKT_SIZE);
> + assert(umem_size % page_size < page_size - PKT_SIZE);
> + }
> + testapp_invalid_desc(test);

Please put this code in a function that you call. Declare your local
variables in the beginning of that function.

> + break;
> case TEST_TYPE_UNALIGNED:
> if (!testapp_unaligned(test))
> return;
> diff --git a/tools/testing/selftests/bpf/xskxceiver.h b/tools/testing/selftests/bpf/xskxceiver.h
> index cc24ab72f3ff..919327807a4e 100644
> --- a/tools/testing/selftests/bpf/xskxceiver.h
> +++ b/tools/testing/selftests/bpf/xskxceiver.h
> @@ -78,6 +78,7 @@ enum test_type {
> TEST_TYPE_ALIGNED_INV_DESC,
> TEST_TYPE_ALIGNED_INV_DESC_2K_FRAME,
> TEST_TYPE_UNALIGNED_INV_DESC,
> + TEST_TYPE_UNALIGNED_INV_DESC_4K1_FRAME,
> TEST_TYPE_HEADROOM,
> TEST_TYPE_TEARDOWN,
> TEST_TYPE_BIDI,
> --
> 2.39.2
>