diff mbox series

[v4,bpf-next,10/10] selftests: xsk: add support for zero copy testing

Message ID 20220616180609.905015-11-maciej.fijalkowski@intel.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series AF_XDP ZC selftests | expand

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Context Check Description
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 10 maintainers not CCed: songliubraving@fb.com hawk@kernel.org linux-kselftest@vger.kernel.org davem@davemloft.net yhs@fb.com john.fastabend@gmail.com kafai@fb.com shuah@kernel.org andrii@kernel.org kpsingh@kernel.org
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/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch warning WARNING: line length of 91 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for Kernel LATEST on ubuntu-latest with gcc
bpf/vmtest-bpf-next-VM_Test-2 success Logs for Kernel LATEST on ubuntu-latest with llvm-15
bpf/vmtest-bpf-next-VM_Test-3 success Logs for Kernel LATEST on z15 with gcc

Commit Message

Fijalkowski, Maciej June 16, 2022, 6:06 p.m. UTC
Introduce new mode to xdpxceiver responsible for testing AF_XDP zero
copy support of driver that serves underlying physical device. When
setting up test suite, determine whether driver has ZC support or not by
trying to bind XSK ZC socket to the interface. If it succeeded,
interpret it as ZC support being in place and do softirq and busy poll
tests for zero copy mode.

Note that Rx dropped tests are skipped since ZC path is not touching
rx_dropped stat at all.

Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
---
 tools/testing/selftests/bpf/xdpxceiver.c | 76 ++++++++++++++++++++++--
 tools/testing/selftests/bpf/xdpxceiver.h |  2 +
 2 files changed, 74 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c
index 13a3b2ac2399..98177ae01e54 100644
--- a/tools/testing/selftests/bpf/xdpxceiver.c
+++ b/tools/testing/selftests/bpf/xdpxceiver.c
@@ -124,9 +124,20 @@  static void __exit_with_error(int error, const char *file, const char *func, int
 }
 
 #define exit_with_error(error) __exit_with_error(error, __FILE__, __func__, __LINE__)
-
-#define mode_string(test) (test)->ifobj_tx->xdp_flags & XDP_FLAGS_SKB_MODE ? "SKB" : "DRV"
 #define busy_poll_string(test) (test)->ifobj_tx->busy_poll ? "BUSY-POLL " : ""
+static char *mode_string(struct test_spec *test)
+{
+	switch (test->mode) {
+	case TEST_MODE_SKB:
+		return "SKB";
+	case TEST_MODE_DRV:
+		return "DRV";
+	case TEST_MODE_ZC:
+		return "ZC";
+	default:
+		return "BOGUS";
+	}
+}
 
 static void report_failure(struct test_spec *test)
 {
@@ -317,6 +328,51 @@  static int __xsk_configure_socket(struct xsk_socket_info *xsk, struct xsk_umem_i
 	return xsk_socket__create(&xsk->xsk, ifobject->ifname, 0, umem->umem, rxr, txr, &cfg);
 }
 
+static bool ifobj_zc_avail(struct ifobject *ifobject)
+{
+	size_t umem_sz = DEFAULT_UMEM_BUFFERS * XSK_UMEM__DEFAULT_FRAME_SIZE;
+	int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
+	struct xsk_socket_info *xsk;
+	struct xsk_umem_info *umem;
+	bool zc_avail = false;
+	void *bufs;
+	int ret;
+
+	bufs = mmap(NULL, umem_sz, PROT_READ | PROT_WRITE, mmap_flags, -1, 0);
+	if (bufs == MAP_FAILED)
+		exit_with_error(errno);
+
+	umem = calloc(1, sizeof(struct xsk_umem_info));
+	if (!umem) {
+		munmap(bufs, umem_sz);
+		exit_with_error(-ENOMEM);
+	}
+	umem->frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE;
+	ret = xsk_configure_umem(umem, bufs, umem_sz);
+	if (ret)
+		exit_with_error(-ret);
+
+	xsk = calloc(1, sizeof(struct xsk_socket_info));
+	if (!xsk)
+		goto out;
+	ifobject->xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+	ifobject->xdp_flags |= XDP_FLAGS_DRV_MODE;
+	ifobject->bind_flags = XDP_USE_NEED_WAKEUP | XDP_ZEROCOPY;
+	ifobject->rx_on = true;
+	xsk->rxqsize = XSK_RING_CONS__DEFAULT_NUM_DESCS;
+	ret = __xsk_configure_socket(xsk, umem, ifobject, false);
+	if (!ret)
+		zc_avail = true;
+
+	xsk_socket__delete(xsk->xsk);
+	free(xsk);
+out:
+	munmap(umem->buffer, umem_sz);
+	xsk_umem__delete(umem->umem);
+	free(umem);
+	return zc_avail;
+}
+
 static struct option long_options[] = {
 	{"interface", required_argument, 0, 'i'},
 	{"busy-poll", no_argument, 0, 'b'},
@@ -483,9 +539,14 @@  static void test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
 		else
 			ifobj->xdp_flags |= XDP_FLAGS_DRV_MODE;
 
-		ifobj->bind_flags = XDP_USE_NEED_WAKEUP | XDP_COPY;
+		ifobj->bind_flags = XDP_USE_NEED_WAKEUP;
+		if (mode == TEST_MODE_ZC)
+			ifobj->bind_flags |= XDP_ZEROCOPY;
+		else
+			ifobj->bind_flags |= XDP_COPY;
 	}
 
+	test->mode = mode;
 	__test_spec_init(test, ifobj_tx, ifobj_rx);
 }
 
@@ -1557,6 +1618,10 @@  static void run_pkt_test(struct test_spec *test, enum test_mode mode, enum test_
 {
 	switch (type) {
 	case TEST_TYPE_STATS_RX_DROPPED:
+		if (mode == TEST_MODE_ZC) {
+			ksft_test_result_skip("Can not run RX_DROPPED test for ZC mode\n");
+			return;
+		}
 		testapp_stats_rx_dropped(test);
 		break;
 	case TEST_TYPE_STATS_TX_INVALID_DESCS:
@@ -1735,8 +1800,11 @@  int main(int argc, char **argv)
 	init_iface(ifobj_rx, MAC2, MAC1, IP2, IP1, UDP_PORT2, UDP_PORT1,
 		   worker_testapp_validate_rx);
 
-	if (is_xdp_supported(ifobj_tx))
+	if (is_xdp_supported(ifobj_tx)) {
 		modes++;
+		if (ifobj_zc_avail(ifobj_tx))
+			modes++;
+	}
 
 	test_spec_init(&test, ifobj_tx, ifobj_rx, 0);
 	tx_pkt_stream_default = pkt_stream_generate(ifobj_tx->umem, DEFAULT_PKT_CNT, PKT_SIZE);
diff --git a/tools/testing/selftests/bpf/xdpxceiver.h b/tools/testing/selftests/bpf/xdpxceiver.h
index f364a92675f8..4e552eb852b9 100644
--- a/tools/testing/selftests/bpf/xdpxceiver.h
+++ b/tools/testing/selftests/bpf/xdpxceiver.h
@@ -61,6 +61,7 @@ 
 enum test_mode {
 	TEST_MODE_SKB,
 	TEST_MODE_DRV,
+	TEST_MODE_ZC,
 	TEST_MODE_MAX
 };
 
@@ -163,6 +164,7 @@  struct test_spec {
 	u16 current_step;
 	u16 nb_sockets;
 	bool fail;
+	enum test_mode mode;
 	char name[MAX_TEST_NAME_SIZE];
 };