diff mbox series

[bpf-next,v1,5/5] selftests/bpf: Update xdp_adjust_frags to use bpf_packet_pointer

Message ID 20220306234311.452206-6-memxor@gmail.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series Introduce bpf_packet_pointer helper | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 6 maintainers not CCed: linux-kselftest@vger.kernel.org kpsingh@kernel.org songliubraving@fb.com shuah@kernel.org yhs@fb.com davem@davemloft.net
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 163 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next success VM_Test

Commit Message

Kumar Kartikeya Dwivedi March 6, 2022, 11:43 p.m. UTC 
Test that in case of linear region, we always are able to do DPA without
any errors. Note how offset is clamped to range [0, 0xffff] and len is a
constant. Ensure that helper vs DPA is detected and tested.

Add a force_helper mode, that forces use of bpf_xdp_load_bytes and
bpf_xdp_store_bytes instead of using bpf_packet_pointer, even for
contiguous regions, to make sure that case keeps working.

Also, we can take this opportunity to convert it to use BPF skeleton.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
---
 .../bpf/prog_tests/xdp_adjust_frags.c         | 46 +++++++++++++------
 .../bpf/progs/test_xdp_update_frags.c         | 46 +++++++++++++------
 2 files changed, 65 insertions(+), 27 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c b/tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c
index 2f033da4cd45..cfb50a575b11 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_adjust_frags.c
@@ -2,26 +2,24 @@ 
 #include <test_progs.h>
 #include <network_helpers.h>
 
-static void test_xdp_update_frags(void)
+#include "test_xdp_update_frags.skel.h"
+
+static void test_xdp_update_frags(bool force_helper)
 {
-	const char *file = "./test_xdp_update_frags.o";
 	int err, prog_fd, max_skb_frags, buf_size, num;
-	struct bpf_program *prog;
-	struct bpf_object *obj;
+	LIBBPF_OPTS(bpf_test_run_opts, topts);
+	struct test_xdp_update_frags *skel;
 	__u32 *offset;
 	__u8 *buf;
 	FILE *f;
-	LIBBPF_OPTS(bpf_test_run_opts, topts);
 
-	obj = bpf_object__open(file);
-	if (libbpf_get_error(obj))
+	skel = test_xdp_update_frags__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "test_xdp_update_frags__open_and_load"))
 		return;
 
-	prog = bpf_object__next_program(obj, NULL);
-	if (bpf_object__load(obj))
-		return;
+	skel->bss->force_helper = force_helper;
 
-	prog_fd = bpf_program__fd(prog);
+	prog_fd = bpf_program__fd(skel->progs.xdp_adjust_frags);
 
 	buf = malloc(128);
 	if (!ASSERT_OK_PTR(buf, "alloc buf 128b"))
@@ -45,6 +43,13 @@  static void test_xdp_update_frags(void)
 	ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
 	ASSERT_EQ(buf[16], 0xbb, "xdp_update_frag buf[16]");
 	ASSERT_EQ(buf[31], 0xbb, "xdp_update_frag buf[31]");
+	if (force_helper) {
+		ASSERT_EQ(skel->bss->used_dpa, false, "did not use DPA");
+		ASSERT_EQ(skel->bss->used_helper, true, "used helper");
+	} else {
+		ASSERT_EQ(skel->bss->used_dpa, true, "used DPA");
+		ASSERT_EQ(skel->bss->used_helper, false, "did not use helper");
+	}
 
 	free(buf);
 
@@ -70,6 +75,13 @@  static void test_xdp_update_frags(void)
 	ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
 	ASSERT_EQ(buf[5000], 0xbb, "xdp_update_frag buf[5000]");
 	ASSERT_EQ(buf[5015], 0xbb, "xdp_update_frag buf[5015]");
+	if (force_helper) {
+		ASSERT_EQ(skel->bss->used_dpa, false, "did not use DPA");
+		ASSERT_EQ(skel->bss->used_helper, true, "used helper");
+	} else {
+		ASSERT_EQ(skel->bss->used_dpa, true, "used DPA");
+		ASSERT_EQ(skel->bss->used_helper, false, "did not use helper");
+	}
 
 	memset(buf, 0, 9000);
 	offset = (__u32 *)buf;
@@ -84,6 +96,8 @@  static void test_xdp_update_frags(void)
 	ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
 	ASSERT_EQ(buf[3510], 0xbb, "xdp_update_frag buf[3510]");
 	ASSERT_EQ(buf[3525], 0xbb, "xdp_update_frag buf[3525]");
+	ASSERT_EQ(skel->bss->used_dpa, false, "did not use DPA");
+	ASSERT_EQ(skel->bss->used_helper, true, "used helper");
 
 	memset(buf, 0, 9000);
 	offset = (__u32 *)buf;
@@ -98,6 +112,8 @@  static void test_xdp_update_frags(void)
 	ASSERT_EQ(topts.retval, XDP_PASS, "xdp_update_frag retval");
 	ASSERT_EQ(buf[7606], 0xbb, "xdp_update_frag buf[7606]");
 	ASSERT_EQ(buf[7621], 0xbb, "xdp_update_frag buf[7621]");
+	ASSERT_EQ(skel->bss->used_dpa, false, "did not use DPA");
+	ASSERT_EQ(skel->bss->used_helper, true, "used helper");
 
 	free(buf);
 
@@ -136,11 +152,13 @@  static void test_xdp_update_frags(void)
 		  "unsupported buf size, possible non-default /proc/sys/net/core/max_skb_flags?");
 	free(buf);
 out:
-	bpf_object__close(obj);
+	test_xdp_update_frags__destroy(skel);
 }
 
 void test_xdp_adjust_frags(void)
 {
-	if (test__start_subtest("xdp_adjust_frags"))
-		test_xdp_update_frags();
+	if (test__start_subtest("xdp_adjust_frags-force-nodpa"))
+		test_xdp_update_frags(true);
+	if (test__start_subtest("xdp_adjust_frags-dpa+memcpy"))
+		test_xdp_update_frags(false);
 }
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c b/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c
index 2a3496d8e327..1ad5c45e06e0 100644
--- a/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c
+++ b/tools/testing/selftests/bpf/progs/test_xdp_update_frags.c
@@ -4,37 +4,57 @@ 
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
-#include <linux/bpf.h>
-#include <linux/if_ether.h>
+#include <vmlinux.h>
 #include <bpf/bpf_helpers.h>
 
 int _version SEC("version") = 1;
 
+bool force_helper;
+bool used_dpa;
+bool used_helper;
+
+#define XDP_LEN 16
+
 SEC("xdp.frags")
 int xdp_adjust_frags(struct xdp_md *xdp)
 {
 	__u8 *data_end = (void *)(long)xdp->data_end;
 	__u8 *data = (void *)(long)xdp->data;
-	__u8 val[16] = {};
+	__u8 val[XDP_LEN] = {};
+	__u8 *ptr = NULL;
 	__u32 offset;
 	int err;
 
+	used_dpa = false;
+	used_helper = false;
+
 	if (data + sizeof(__u32) > data_end)
 		return XDP_DROP;
 
 	offset = *(__u32 *)data;
-	err = bpf_xdp_load_bytes(xdp, offset, val, sizeof(val));
-	if (err < 0)
+	offset &= 0xffff;
+	if (!force_helper)
+		ptr = bpf_packet_pointer(xdp, offset, XDP_LEN);
+	if (!ptr) {
+		used_helper = true;
+		err = bpf_xdp_load_bytes(xdp, offset, val, sizeof(val));
+		if (err < 0)
+			return XDP_DROP;
+		ptr = val;
+	} else {
+		used_dpa = true;
+	}
+
+	if (ptr[0] != 0xaa || ptr[15] != 0xaa) /* marker */
 		return XDP_DROP;
 
-	if (val[0] != 0xaa || val[15] != 0xaa) /* marker */
-		return XDP_DROP;
-
-	val[0] = 0xbb; /* update the marker */
-	val[15] = 0xbb;
-	err = bpf_xdp_store_bytes(xdp, offset, val, sizeof(val));
-	if (err < 0)
-		return XDP_DROP;
+	ptr[0] = 0xbb; /* update the marker */
+	ptr[15] = 0xbb;
+	if (ptr == val) {
+		err = bpf_xdp_store_bytes(xdp, offset, val, sizeof(val));
+		if (err < 0)
+			return XDP_DROP;
+	}
 
 	return XDP_PASS;
 }