Commit fa0d27a1 authored by Ong Boon Leong's avatar Ong Boon Leong Committed by Alexei Starovoitov
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samples/bpf: xdpsock: Add cyclic TX operation capability 



Tx cycle time is in micro-seconds unit. By combining the batch size (-b M)
and Tx cycle time (-T|--tx-cycle N), xdpsock now can transmit batch-size of
packets every N-us periodically. Cyclic TX operation is not applicable if
--poll mode is used.

To transmit 16 packets every 1ms cycle time for total of 100000 packets
silently:
 $ xdpsock -i eth0 -T -N -z -T 1000 -b 16 -C 100000

To print cyclic TX schedule variance stats, use --app-stats|-a:
 $ xdpsock -i eth0 -T -N -z -T 1000 -b 16 -C 100000 -a

 sock0@eth0:0 txonly xdp-drv
                   pps            pkts           0.00
rx                 0              0
tx                 0              100000

                   calls/s        count
rx empty polls     0              0
fill fail polls    0              0
copy tx sendtos    0              0
tx wakeup sendtos  0              6254
opt polls          0              0

                   period     min        ave        max        cycle
Cyclic TX          1000000    53507      75334      712642     6250

Signed-off-by: default avatarOng Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211230035447.523177-5-boon.leong.ong@intel.com
parent 5a388254

samples/bpf/xdpsock_user.c

+80 −5
Original line number Diff line number Diff line
@@ -63,12 +63,19 @@ 
#define VLAN_VID__DEFAULT	1

#define VLAN_PRI__DEFAULT	0



#define NSEC_PER_SEC		1000000000UL

#define NSEC_PER_USEC		1000



typedef __u64 u64;

typedef __u32 u32;

typedef __u16 u16;

typedef __u8  u8;



static unsigned long prev_time;

static long tx_cycle_diff_min;

static long tx_cycle_diff_max;

static double tx_cycle_diff_ave;

static long tx_cycle_cnt;



enum benchmark_type {

	BENCH_RXDROP = 0,
@@ -115,6 +122,7 @@ static u32 prog_id; 
static bool opt_busy_poll;

static bool opt_reduced_cap;

static clockid_t opt_clock = CLOCK_MONOTONIC;

static unsigned long opt_tx_cycle_ns;



struct vlan_ethhdr {

	unsigned char h_dest[6];
@@ -305,6 +313,15 @@ static void dump_app_stats(long dt) 
		xsks[i]->app_stats.prev_tx_wakeup_sendtos = xsks[i]->app_stats.tx_wakeup_sendtos;

		xsks[i]->app_stats.prev_opt_polls = xsks[i]->app_stats.opt_polls;

	}



	if (opt_tx_cycle_ns) {

		printf("\n%-18s %-10s %-10s %-10s %-10s %-10s\n",

		       "", "period", "min", "ave", "max", "cycle");

		printf("%-18s %-10lu %-10lu %-10lu %-10lu %-10lu\n",

		       "Cyclic TX", opt_tx_cycle_ns, tx_cycle_diff_min,

		       (long)(tx_cycle_diff_ave / tx_cycle_cnt),

		       tx_cycle_diff_max, tx_cycle_cnt);

	}

}



static bool get_interrupt_number(void)
@@ -1001,6 +1018,7 @@ static struct option long_options[] = { 
	{"tx-vlan-pri", required_argument, 0, 'K'},

	{"tx-dmac", required_argument, 0, 'G'},

	{"tx-smac", required_argument, 0, 'H'},

	{"tx-cycle", required_argument, 0, 'T'},

	{"extra-stats", no_argument, 0, 'x'},

	{"quiet", no_argument, 0, 'Q'},

	{"app-stats", no_argument, 0, 'a'},
@@ -1047,6 +1065,7 @@ static void usage(const char *prog) 
		"  -K, --tx-vlan-pri=n  Tx VLAN Priority [0-7]. Default: %d (For -V|--tx-vlan)\n"

		"  -G, --tx-dmac=<MAC>  Dest MAC addr of TX frame in aa:bb:cc:dd:ee:ff format (For -V|--tx-vlan)\n"

		"  -H, --tx-smac=<MAC>  Src MAC addr of TX frame in aa:bb:cc:dd:ee:ff format (For -V|--tx-vlan)\n"

		"  -T, --tx-cycle=n     Tx cycle time in micro-seconds (For -t|--txonly).\n"

		"  -x, --extra-stats	Display extra statistics.\n"

		"  -Q, --quiet          Do not display any stats.\n"

		"  -a, --app-stats	Display application (syscall) statistics.\n"
@@ -1069,7 +1088,7 @@ static void parse_command_line(int argc, char **argv) 
	opterr = 0;



	for (;;) {

		c = getopt_long(argc, argv, "Frtli:q:pSNn:w:czf:muMd:b:C:s:P:VJ:K:G:H:xQaI:BR",

		c = getopt_long(argc, argv, "Frtli:q:pSNn:w:czf:muMd:b:C:s:P:VJ:K:G:H:T:xQaI:BR",

				long_options, &option_index);

		if (c == -1)

			break;
@@ -1183,6 +1202,10 @@ static void parse_command_line(int argc, char **argv) 
				usage(basename(argv[0]));

			}

			break;

		case 'T':

			opt_tx_cycle_ns = atoi(optarg);

			opt_tx_cycle_ns *= NSEC_PER_USEC;

			break;

		case 'x':

			opt_extra_stats = 1;

			break;
@@ -1388,7 +1411,7 @@ static void rx_drop_all(void) 
	}

}



static void tx_only(struct xsk_socket_info *xsk, u32 *frame_nb, int batch_size)

static int tx_only(struct xsk_socket_info *xsk, u32 *frame_nb, int batch_size)

{

	u32 idx;

	unsigned int i;
@@ -1397,7 +1420,7 @@ static void tx_only(struct xsk_socket_info *xsk, u32 *frame_nb, int batch_size) 
				      batch_size) {

		complete_tx_only(xsk, batch_size);

		if (benchmark_done)

			return;

			return 0;

	}



	for (i = 0; i < batch_size; i++) {
@@ -1413,6 +1436,8 @@ static void tx_only(struct xsk_socket_info *xsk, u32 *frame_nb, int batch_size) 
	*frame_nb += batch_size;

	*frame_nb %= NUM_FRAMES;

	complete_tx_only(xsk, batch_size);



	return batch_size;

}



static inline int get_batch_size(int pkt_cnt)
@@ -1446,16 +1471,39 @@ static void tx_only_all(void) 
{

	struct pollfd fds[MAX_SOCKS] = {};

	u32 frame_nb[MAX_SOCKS] = {};

	unsigned long next_tx_ns = 0;

	int pkt_cnt = 0;

	int i, ret;



	if (opt_poll && opt_tx_cycle_ns) {

		fprintf(stderr,

			"Error: --poll and --tx-cycles are both set\n");

		return;

	}



	for (i = 0; i < num_socks; i++) {

		fds[0].fd = xsk_socket__fd(xsks[i]->xsk);

		fds[0].events = POLLOUT;

	}



	if (opt_tx_cycle_ns) {

		/* Align Tx time to micro-second boundary */

		next_tx_ns = (get_nsecs() / NSEC_PER_USEC + 1) *

			     NSEC_PER_USEC;

		next_tx_ns += opt_tx_cycle_ns;



		/* Initialize periodic Tx scheduling variance */

		tx_cycle_diff_min = 1000000000;

		tx_cycle_diff_max = 0;

		tx_cycle_diff_ave = 0.0;

	}



	while ((opt_pkt_count && pkt_cnt < opt_pkt_count) || !opt_pkt_count) {

		int batch_size = get_batch_size(pkt_cnt);

		struct timespec next;

		int tx_cnt = 0;

		long diff;

		int err;



		if (opt_poll) {

			for (i = 0; i < num_socks; i++)
@@ -1468,13 +1516,40 @@ static void tx_only_all(void) 
				continue;

		}



		if (opt_tx_cycle_ns) {

			next.tv_sec = next_tx_ns / NSEC_PER_SEC;

			next.tv_nsec = next_tx_ns % NSEC_PER_SEC;

			err = clock_nanosleep(opt_clock, TIMER_ABSTIME, &next, NULL);

			if (err) {

				if (err != EINTR)

					fprintf(stderr,

						"clock_nanosleep failed. Err:%d errno:%d\n",

						err, errno);

				break;

			}



			/* Measure periodic Tx scheduling variance */

			diff = get_nsecs() - next_tx_ns;

			if (diff < tx_cycle_diff_min)

				tx_cycle_diff_min = diff;



			if (diff > tx_cycle_diff_max)

				tx_cycle_diff_max = diff;



			tx_cycle_diff_ave += (double)diff;

			tx_cycle_cnt++;

		}



		for (i = 0; i < num_socks; i++)

			tx_only(xsks[i], &frame_nb[i], batch_size);

			tx_cnt += tx_only(xsks[i], &frame_nb[i], batch_size);



		pkt_cnt += batch_size;

		pkt_cnt += tx_cnt;



		if (benchmark_done)

			break;



		if (opt_tx_cycle_ns)

			next_tx_ns += opt_tx_cycle_ns;

	}



	if (opt_pkt_count)