samples/bpf: Add busy-poll support to xdpsock

Add a new option to xdpsock, 'B', for busy-polling. This option will
also set the batching size, 'b' option, to the busy-poll budget.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20201130185205.196029-10-bjorn.topel@gmail.com
This commit is contained in:
Björn Töpel 2020-11-30 19:52:04 +01:00 committed by Daniel Borkmann
parent 284cbc61f8
commit b35fc1482c

View File

@ -95,6 +95,7 @@ static int opt_timeout = 1000;
static bool opt_need_wakeup = true;
static u32 opt_num_xsks = 1;
static u32 prog_id;
static bool opt_busy_poll;
struct xsk_ring_stats {
unsigned long rx_npkts;
@ -911,6 +912,7 @@ static struct option long_options[] = {
{"quiet", no_argument, 0, 'Q'},
{"app-stats", no_argument, 0, 'a'},
{"irq-string", no_argument, 0, 'I'},
{"busy-poll", no_argument, 0, 'B'},
{0, 0, 0, 0}
};
@ -949,6 +951,7 @@ static void usage(const char *prog)
" -Q, --quiet Do not display any stats.\n"
" -a, --app-stats Display application (syscall) statistics.\n"
" -I, --irq-string Display driver interrupt statistics for interface associated with irq-string.\n"
" -B, --busy-poll Busy poll.\n"
"\n";
fprintf(stderr, str, prog, XSK_UMEM__DEFAULT_FRAME_SIZE,
opt_batch_size, MIN_PKT_SIZE, MIN_PKT_SIZE,
@ -964,7 +967,7 @@ static void parse_command_line(int argc, char **argv)
opterr = 0;
for (;;) {
c = getopt_long(argc, argv, "Frtli:q:pSNn:czf:muMd:b:C:s:P:xQaI:",
c = getopt_long(argc, argv, "Frtli:q:pSNn:czf:muMd:b:C:s:P:xQaI:B",
long_options, &option_index);
if (c == -1)
break;
@ -1062,7 +1065,9 @@ static void parse_command_line(int argc, char **argv)
fprintf(stderr, "ERROR: Failed to get irqs for %s\n", opt_irq_str);
usage(basename(argv[0]));
}
break;
case 'B':
opt_busy_poll = 1;
break;
default:
usage(basename(argv[0]));
@ -1131,7 +1136,7 @@ static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk)
while (ret != rcvd) {
if (ret < 0)
exit_with_error(-ret);
if (xsk_ring_prod__needs_wakeup(&umem->fq)) {
if (opt_busy_poll || xsk_ring_prod__needs_wakeup(&umem->fq)) {
xsk->app_stats.fill_fail_polls++;
recvfrom(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL,
NULL);
@ -1178,7 +1183,7 @@ static void rx_drop(struct xsk_socket_info *xsk)
rcvd = xsk_ring_cons__peek(&xsk->rx, opt_batch_size, &idx_rx);
if (!rcvd) {
if (xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
if (opt_busy_poll || xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
xsk->app_stats.rx_empty_polls++;
recvfrom(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL, NULL);
}
@ -1189,7 +1194,7 @@ static void rx_drop(struct xsk_socket_info *xsk)
while (ret != rcvd) {
if (ret < 0)
exit_with_error(-ret);
if (xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
if (opt_busy_poll || xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
xsk->app_stats.fill_fail_polls++;
recvfrom(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL, NULL);
}
@ -1341,7 +1346,7 @@ static void l2fwd(struct xsk_socket_info *xsk)
rcvd = xsk_ring_cons__peek(&xsk->rx, opt_batch_size, &idx_rx);
if (!rcvd) {
if (xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
if (opt_busy_poll || xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) {
xsk->app_stats.rx_empty_polls++;
recvfrom(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_DONTWAIT, NULL, NULL);
}
@ -1354,7 +1359,7 @@ static void l2fwd(struct xsk_socket_info *xsk)
if (ret < 0)
exit_with_error(-ret);
complete_tx_l2fwd(xsk);
if (xsk_ring_prod__needs_wakeup(&xsk->tx)) {
if (opt_busy_poll || xsk_ring_prod__needs_wakeup(&xsk->tx)) {
xsk->app_stats.tx_wakeup_sendtos++;
kick_tx(xsk);
}
@ -1459,6 +1464,24 @@ static void enter_xsks_into_map(struct bpf_object *obj)
}
}
static void apply_setsockopt(struct xsk_socket_info *xsk)
{
int sock_opt;
if (!opt_busy_poll)
return;
sock_opt = 1;
if (setsockopt(xsk_socket__fd(xsk->xsk), SOL_SOCKET, SO_PREFER_BUSY_POLL,
(void *)&sock_opt, sizeof(sock_opt)) < 0)
exit_with_error(errno);
sock_opt = 20;
if (setsockopt(xsk_socket__fd(xsk->xsk), SOL_SOCKET, SO_BUSY_POLL,
(void *)&sock_opt, sizeof(sock_opt)) < 0)
exit_with_error(errno);
}
int main(int argc, char **argv)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
@ -1500,6 +1523,9 @@ int main(int argc, char **argv)
for (i = 0; i < opt_num_xsks; i++)
xsks[num_socks++] = xsk_configure_socket(umem, rx, tx);
for (i = 0; i < opt_num_xsks; i++)
apply_setsockopt(xsks[i]);
if (opt_bench == BENCH_TXONLY) {
gen_eth_hdr_data();