Commit 34e78bab authored by Alexei Starovoitov's avatar Alexei Starovoitov
Browse files

Merge branch 'seltests/xsk: prepare for AF_XDP multi-buffer testing' 



Magnus Karlsson says:

====================
Prepare the AF_XDP selftests test framework code for the upcoming
multi-buffer support in AF_XDP. This so that the multi-buffer patch
set does not become way too large. In that upcoming patch set, we are
only including the multi-buffer tests together with any framework
code that depends on the new options bit introduced in the AF_XDP
multi-buffer implementation itself.

Currently, the test framework is based on the premise that a packet
consists of a single fragment and thus occupies a single buffer and a
single descriptor. Multi-buffer breaks this assumption, as that is the
whole purpose of it. Now, a packet can consist of multiple buffers and
therefore consume multiple descriptors.

The patch set starts with some clean-ups and simplifications followed
by patches that make sure that the current code works even when a
packet occupies multiple buffers. The actual code for sending and
receiving multi-buffer packets will be included in the AF_XDP
multi-buffer patch set as it depends on a new bit being used in the
options field of the descriptor.

Patch set anatomy:
1: The XDP program was unnecessarily changed many times. Fixes this.

2: There is no reason to generate a full UDP/IPv4 packet as it is
   never used. Simplify the code by just generating a valid Ethernet
   frame.

3: Introduce a more complicated payload pattern that can detect
   fragments out of bounds in a multi-buffer packet and other errors
   found in single-fragment packets.

4: As a convenience, dump the content of the faulty packet at error.

5: To simplify the code, make the usage of the packet stream for Tx
   and Rx more similar.

6: Store the offset of the packet in the buffer in the struct pkt
   definition instead of the address in the umem itself and introduce
   a simple buffer allocator. The address only made sense when all
   packets consumed a single buffer. Now, we do not know beforehand
   how many buffers a packet will consume, so we instead just allocate
   a buffer from the allocator and specify the offset within that
   buffer.

7: Test for huge pages only once instead of before each test that needs it.

8: Populate the fill ring based on how many frags are needed for each
   packet.

9: Change the data generation code so it can generate data for
   multi-buffer packets too.

10: Adjust the packet pacing algorithm so that it can cope with
    multi-buffer packets. The pacing algorithm is present so that Tx
    does not send too many packets/frames to Rx that it starts to drop
    packets. That would ruin the tests.

v1 -> v2:
* Fixed spelling error in patch #6 [Simon]
* Fixed compilation error with llvm in patch #7 [Daniel]

Thanks: Magnus
====================

Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parents 0697e439 7cd6df4f

tools/testing/selftests/bpf/test_xsk.sh

+1 −9
Original line number Diff line number Diff line
@@ -68,9 +68,6 @@ 
# Run with verbose output:

#   sudo ./test_xsk.sh -v

#

# Run and dump packet contents:

#   sudo ./test_xsk.sh -D

#

# Set up veth interfaces and leave them up so xskxceiver can be launched in a debugger:

#   sudo ./test_xsk.sh -d

#
@@ -81,11 +78,10 @@ 


ETH=""



while getopts "vDi:d" flag

while getopts "vi:d" flag

do

	case "${flag}" in

		v) verbose=1;;

		D) dump_pkts=1;;

		d) debug=1;;

		i) ETH=${OPTARG};;

	esac
@@ -157,10 +153,6 @@ if [[ $verbose -eq 1 ]]; then 
	ARGS+="-v "

fi



if [[ $dump_pkts -eq 1 ]]; then

	ARGS="-D "

fi



retval=$?

test_status $retval "${TEST_NAME}"

tools/testing/selftests/bpf/xsk.h

+5 −0
Original line number Diff line number Diff line
@@ -134,6 +134,11 @@ static inline void xsk_ring_prod__submit(struct xsk_ring_prod *prod, __u32 nb) 
	__atomic_store_n(prod->producer, *prod->producer + nb, __ATOMIC_RELEASE);

}



static inline void xsk_ring_prod__cancel(struct xsk_ring_prod *prod, __u32 nb)

{

	prod->cached_prod -= nb;

}



static inline __u32 xsk_ring_cons__peek(struct xsk_ring_cons *cons, __u32 nb, __u32 *idx)

{

	__u32 entries = xsk_cons_nb_avail(cons, nb);

tools/testing/selftests/bpf/xskxceiver.c

+363 −408

File changed.

Preview size limit exceeded, changes collapsed.

tools/testing/selftests/bpf/xskxceiver.h

+10 −21
Original line number Diff line number Diff line
@@ -30,22 +30,14 @@ 
#define TEST_PASS 0

#define TEST_FAILURE -1

#define TEST_CONTINUE 1

#define TEST_SKIP 2

#define MAX_INTERFACES 2

#define MAX_INTERFACE_NAME_CHARS 16

#define MAX_SOCKETS 2

#define MAX_TEST_NAME_SIZE 32

#define MAX_TEARDOWN_ITER 10

#define PKT_HDR_SIZE (sizeof(struct ethhdr) + sizeof(struct iphdr) + \

			sizeof(struct udphdr))

#define MIN_ETH_PKT_SIZE 64

#define ETH_FCS_SIZE 4

#define MIN_PKT_SIZE (MIN_ETH_PKT_SIZE - ETH_FCS_SIZE)

#define PKT_SIZE (MIN_PKT_SIZE)

#define IP_PKT_SIZE (PKT_SIZE - sizeof(struct ethhdr))

#define IP_PKT_VER 0x4

#define IP_PKT_TOS 0x9

#define UDP_PKT_SIZE (IP_PKT_SIZE - sizeof(struct iphdr))

#define UDP_PKT_DATA_SIZE (UDP_PKT_SIZE - sizeof(struct udphdr))

#define PKT_HDR_SIZE (sizeof(struct ethhdr) + 2) /* Just to align the data in the packet */

#define MIN_PKT_SIZE 64

#define USLEEP_MAX 10000

#define SOCK_RECONF_CTR 10

#define BATCH_SIZE 64
@@ -57,6 +49,7 @@ 
#define UMEM_HEADROOM_TEST_SIZE 128

#define XSK_UMEM__INVALID_FRAME_SIZE (XSK_UMEM__DEFAULT_FRAME_SIZE + 1)

#define HUGEPAGE_SIZE (2 * 1024 * 1024)

#define PKT_DUMP_NB_TO_PRINT 16



#define print_verbose(x...) do { if (opt_verbose) ksft_print_msg(x); } while (0)
@@ -93,13 +86,13 @@ enum test_type { 
	TEST_TYPE_MAX

};



static bool opt_pkt_dump;

static bool opt_verbose;



struct xsk_umem_info {

	struct xsk_ring_prod fq;

	struct xsk_ring_cons cq;

	struct xsk_umem *umem;

	u64 next_buffer;

	u32 num_frames;

	u32 frame_headroom;

	void *buffer;
@@ -118,17 +111,17 @@ struct xsk_socket_info { 
};



struct pkt {

	u64 addr;

	int offset;

	u32 len;

	u32 payload;

	u32 pkt_nb;

	bool valid;

};



struct pkt_stream {

	u32 nb_pkts;

	u32 rx_pkt_nb;

	u32 current_pkt_nb;

	struct pkt *pkts;

	bool use_addr_for_fill;

	u32 max_pkt_len;

};



struct ifobject;
@@ -148,11 +141,7 @@ struct ifobject { 
	struct bpf_program *xdp_prog;

	enum test_mode mode;

	int ifindex;

	u32 dst_ip;

	u32 src_ip;

	u32 bind_flags;

	u16 src_port;

	u16 dst_port;

	bool tx_on;

	bool rx_on;

	bool use_poll;
@@ -161,6 +150,7 @@ struct ifobject { 
	bool release_rx;

	bool shared_umem;

	bool use_metadata;

	bool unaligned_supp;

	u8 dst_mac[ETH_ALEN];

	u8 src_mac[ETH_ALEN];

};
@@ -184,7 +174,6 @@ struct test_spec { 


pthread_barrier_t barr;

pthread_mutex_t pacing_mutex = PTHREAD_MUTEX_INITIALIZER;

pthread_cond_t pacing_cond = PTHREAD_COND_INITIALIZER;



int pkts_in_flight;