On Fri, May 24, 2019 at 4:59 AM Ye Xiaolong <xiaolong.ye@xxxxxxxxx> wrote:
>
> Hi, Magnus
>
> On 05/02, Magnus Karlsson wrote:
> >This patch adds busy-poll support to the xdpsock sample
> >application. It is enabled by the "-b" or the "--busy-poll" command
> >line options.
> >
> >Signed-off-by: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
> >---
> > samples/bpf/xdpsock_user.c | 203 ++++++++++++++++++++++++++++-----------------
> > 1 file changed, 125 insertions(+), 78 deletions(-)
> >
> >diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
> >index d08ee1a..1272edf 100644
> >--- a/samples/bpf/xdpsock_user.c
> >+++ b/samples/bpf/xdpsock_user.c
> >@@ -66,6 +66,7 @@ static const char *opt_if = "";
> > static int opt_ifindex;
> > static int opt_queue;
> > static int opt_poll;
> >+static int opt_busy_poll;
> > static int opt_interval = 1;
> > static u32 opt_xdp_bind_flags;
> > static __u32 prog_id;
> >@@ -119,8 +120,11 @@ static void print_benchmark(bool running)
> > else
> > printf(" ");
> >
> >- if (opt_poll)
> >+ if (opt_poll) {
> >+ if (opt_busy_poll)
> >+ printf("busy-");
> > printf("poll() ");
> >+ }
> >
> > if (running) {
> > printf("running...");
> >@@ -306,7 +310,7 @@ static struct xsk_socket_info *xsk_configure_socket(struct xsk_umem_info *umem)
> > xsk->umem = umem;
> > cfg.rx_size = XSK_RING_CONS__DEFAULT_NUM_DESCS;
> > cfg.tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS;
> >- cfg.libbpf_flags = 0;
>
> Any purpose for removing this line, as cfg here is a local variable, cfg.libbpf_flags
> can be random and may lead to xdpsock failure as `Invalid no_argument`.
No, that was a mistake. Thanks for catching.
I will produce a new patch set with the improvements needed to make
execution of application and softirq/ksoftirqd on the same core
efficient, make a v2 of the busy poll patch set (with all your
suggested improvements) on top of that, and then see what performance
we have.
Thanks: Magnus
> Thanks,
> Xiaolong
>
> >+ cfg.busy_poll = (opt_busy_poll ? BATCH_SIZE : 0);
> > cfg.xdp_flags = opt_xdp_flags;
> > cfg.bind_flags = opt_xdp_bind_flags;
> > ret = xsk_socket__create(&xsk->xsk, opt_if, opt_queue, umem->umem,
> >@@ -319,17 +323,17 @@ static struct xsk_socket_info *xsk_configure_socket(struct xsk_umem_info *umem)
> > exit_with_error(-ret);
> >
> > ret = xsk_ring_prod__reserve(&xsk->umem->fq,
> >- XSK_RING_PROD__DEFAULT_NUM_DESCS,
> >+ 1024,
> > &idx);
> >- if (ret != XSK_RING_PROD__DEFAULT_NUM_DESCS)
> >+ if (ret != 1024)
> > exit_with_error(-ret);
> > for (i = 0;
> >- i < XSK_RING_PROD__DEFAULT_NUM_DESCS *
> >+ i < 1024 *
> > XSK_UMEM__DEFAULT_FRAME_SIZE;
> > i += XSK_UMEM__DEFAULT_FRAME_SIZE)
> > *xsk_ring_prod__fill_addr(&xsk->umem->fq, idx++) = i;
> > xsk_ring_prod__submit(&xsk->umem->fq,
> >- XSK_RING_PROD__DEFAULT_NUM_DESCS);
> >+ 1024);
> >
> > return xsk;
> > }
> >@@ -341,6 +345,7 @@ static struct option long_options[] = {
> > {"interface", required_argument, 0, 'i'},
> > {"queue", required_argument, 0, 'q'},
> > {"poll", no_argument, 0, 'p'},
> >+ {"busy-poll", no_argument, 0, 'b'},
> > {"xdp-skb", no_argument, 0, 'S'},
> > {"xdp-native", no_argument, 0, 'N'},
> > {"interval", required_argument, 0, 'n'},
> >@@ -360,6 +365,7 @@ static void usage(const char *prog)
> > " -i, --interface=n Run on interface n\n"
> > " -q, --queue=n Use queue n (default 0)\n"
> > " -p, --poll Use poll syscall\n"
> >+ " -b, --busy-poll Use poll syscall with busy poll\n"
> > " -S, --xdp-skb=n Use XDP skb-mod\n"
> > " -N, --xdp-native=n Enfore XDP native mode\n"
> > " -n, --interval=n Specify statistics update interval (default 1 sec).\n"
> >@@ -377,7 +383,7 @@ static void parse_command_line(int argc, char **argv)
> > opterr = 0;
> >
> > for (;;) {
> >- c = getopt_long(argc, argv, "Frtli:q:psSNn:cz", long_options,
> >+ c = getopt_long(argc, argv, "Frtli:q:pbsSNn:cz", long_options,
> > &option_index);
> > if (c == -1)
> > break;
> >@@ -401,6 +407,10 @@ static void parse_command_line(int argc, char **argv)
> > case 'p':
> > opt_poll = 1;
> > break;
> >+ case 'b':
> >+ opt_busy_poll = 1;
> >+ opt_poll = 1;
> >+ break;
> > case 'S':
> > opt_xdp_flags |= XDP_FLAGS_SKB_MODE;
> > opt_xdp_bind_flags |= XDP_COPY;
> >@@ -444,7 +454,8 @@ static void kick_tx(struct xsk_socket_info *xsk)
> > exit_with_error(errno);
> > }
> >
> >-static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk)
> >+static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk,
> >+ struct pollfd *fds)
> > {
> > u32 idx_cq = 0, idx_fq = 0;
> > unsigned int rcvd;
> >@@ -453,7 +464,8 @@ static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk)
> > if (!xsk->outstanding_tx)
> > return;
> >
> >- kick_tx(xsk);
> >+ if (!opt_poll)
> >+ kick_tx(xsk);
> > ndescs = (xsk->outstanding_tx > BATCH_SIZE) ? BATCH_SIZE :
> > xsk->outstanding_tx;
> >
> >@@ -467,6 +479,8 @@ static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk)
> > while (ret != rcvd) {
> > if (ret < 0)
> > exit_with_error(-ret);
> >+ if (opt_busy_poll)
> >+ ret = poll(fds, num_socks, 0);
> > ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd,
> > &idx_fq);
> > }
> >@@ -490,7 +504,8 @@ static inline void complete_tx_only(struct xsk_socket_info *xsk)
> > if (!xsk->outstanding_tx)
> > return;
> >
> >- kick_tx(xsk);
> >+ if (!opt_busy_poll)
> >+ kick_tx(xsk);
> >
> > rcvd = xsk_ring_cons__peek(&xsk->umem->cq, BATCH_SIZE, &idx);
> > if (rcvd > 0) {
> >@@ -500,10 +515,10 @@ static inline void complete_tx_only(struct xsk_socket_info *xsk)
> > }
> > }
> >
> >-static void rx_drop(struct xsk_socket_info *xsk)
> >+static void rx_drop(struct xsk_socket_info *xsk, struct pollfd *fds)
> > {
> >- unsigned int rcvd, i;
> > u32 idx_rx = 0, idx_fq = 0;
> >+ unsigned int rcvd, i;
> > int ret;
> >
> > rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE, &idx_rx);
> >@@ -514,6 +529,8 @@ static void rx_drop(struct xsk_socket_info *xsk)
> > while (ret != rcvd) {
> > if (ret < 0)
> > exit_with_error(-ret);
> >+ if (opt_busy_poll)
> >+ ret = poll(fds, num_socks, 0);
> > ret = xsk_ring_prod__reserve(&xsk->umem->fq, rcvd, &idx_fq);
> > }
> >
> >@@ -533,43 +550,68 @@ static void rx_drop(struct xsk_socket_info *xsk)
> >
> > static void rx_drop_all(void)
> > {
> >- struct pollfd fds[MAX_SOCKS + 1];
> >- int i, ret, timeout, nfds = 1;
> >+ struct pollfd fds[MAX_SOCKS];
> >+ int i, ret;
> >
> > memset(fds, 0, sizeof(fds));
> >
> > for (i = 0; i < num_socks; i++) {
> > fds[i].fd = xsk_socket__fd(xsks[i]->xsk);
> > fds[i].events = POLLIN;
> >- timeout = 1000; /* 1sn */
> > }
> >
> > for (;;) {
> > if (opt_poll) {
> >- ret = poll(fds, nfds, timeout);
> >+ ret = poll(fds, num_socks, 0);
> > if (ret <= 0)
> > continue;
> > }
> >
> > for (i = 0; i < num_socks; i++)
> >- rx_drop(xsks[i]);
> >+ rx_drop(xsks[i], fds);
> >+ }
> >+}
> >+
> >+static void tx_only(struct xsk_socket_info *xsk, u32 frame_nb)
> >+{
> >+ u32 idx;
> >+
> >+ if (xsk_ring_prod__reserve(&xsk->tx, BATCH_SIZE, &idx) ==
> >+ BATCH_SIZE) {
> >+ unsigned int i;
> >+
> >+ for (i = 0; i < BATCH_SIZE; i++) {
> >+ xsk_ring_prod__tx_desc(&xsk->tx, idx + i)->addr
> >+ = (frame_nb + i) <<
> >+ XSK_UMEM__DEFAULT_FRAME_SHIFT;
> >+ xsk_ring_prod__tx_desc(&xsk->tx, idx + i)->len =
> >+ sizeof(pkt_data) - 1;
> >+ }
> >+
> >+ xsk_ring_prod__submit(&xsk->tx, BATCH_SIZE);
> >+ xsk->outstanding_tx += BATCH_SIZE;
> >+ frame_nb += BATCH_SIZE;
> >+ frame_nb %= NUM_FRAMES;
> > }
> >+
> >+ complete_tx_only(xsk);
> > }
> >
> >-static void tx_only(struct xsk_socket_info *xsk)
> >+static void tx_only_all(void)
> > {
> >- int timeout, ret, nfds = 1;
> >- struct pollfd fds[nfds + 1];
> >- u32 idx, frame_nb = 0;
> >+ struct pollfd fds[MAX_SOCKS];
> >+ u32 frame_nb[MAX_SOCKS] = {};
> >+ int i, ret;
> >
> > memset(fds, 0, sizeof(fds));
> >- fds[0].fd = xsk_socket__fd(xsk->xsk);
> >- fds[0].events = POLLOUT;
> >- timeout = 1000; /* 1sn */
> >+ for (i = 0; i < num_socks; i++) {
> >+ fds[0].fd = xsk_socket__fd(xsks[i]->xsk);
> >+ fds[0].events = POLLOUT;
> >+ }
> >
> > for (;;) {
> > if (opt_poll) {
> >- ret = poll(fds, nfds, timeout);
> >+ ret = poll(fds, num_socks, 0);
> > if (ret <= 0)
> > continue;
> >
> >@@ -577,70 +619,75 @@ static void tx_only(struct xsk_socket_info *xsk)
> > continue;
> > }
> >
> >- if (xsk_ring_prod__reserve(&xsk->tx, BATCH_SIZE, &idx) ==
> >- BATCH_SIZE) {
> >- unsigned int i;
> >-
> >- for (i = 0; i < BATCH_SIZE; i++) {
> >- xsk_ring_prod__tx_desc(&xsk->tx, idx + i)->addr
> >- = (frame_nb + i) <<
> >- XSK_UMEM__DEFAULT_FRAME_SHIFT;
> >- xsk_ring_prod__tx_desc(&xsk->tx, idx + i)->len =
> >- sizeof(pkt_data) - 1;
> >- }
> >-
> >- xsk_ring_prod__submit(&xsk->tx, BATCH_SIZE);
> >- xsk->outstanding_tx += BATCH_SIZE;
> >- frame_nb += BATCH_SIZE;
> >- frame_nb %= NUM_FRAMES;
> >- }
> >-
> >- complete_tx_only(xsk);
> >+ for (i = 0; i < num_socks; i++)
> >+ tx_only(xsks[i], frame_nb[i]);
> > }
> > }
> >
> >-static void l2fwd(struct xsk_socket_info *xsk)
> >+static void l2fwd(struct xsk_socket_info *xsk, struct pollfd *fds)
> > {
> >- for (;;) {
> >- unsigned int rcvd, i;
> >- u32 idx_rx = 0, idx_tx = 0;
> >- int ret;
> >+ unsigned int rcvd, i;
> >+ u32 idx_rx = 0, idx_tx = 0;
> >+ int ret;
> >
> >- for (;;) {
> >- complete_tx_l2fwd(xsk);
> >+ complete_tx_l2fwd(xsk, fds);
> >
> >- rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE,
> >- &idx_rx);
> >- if (rcvd > 0)
> >- break;
> >- }
> >+ rcvd = xsk_ring_cons__peek(&xsk->rx, BATCH_SIZE,
> >+ &idx_rx);
> >+ if (!rcvd)
> >+ return;
> >
> >+ ret = xsk_ring_prod__reserve(&xsk->tx, rcvd, &idx_tx);
> >+ while (ret != rcvd) {
> >+ if (ret < 0)
> >+ exit_with_error(-ret);
> >+ if (opt_busy_poll)
> >+ ret = poll(fds, num_socks, 0);
> > ret = xsk_ring_prod__reserve(&xsk->tx, rcvd, &idx_tx);
> >- while (ret != rcvd) {
> >- if (ret < 0)
> >- exit_with_error(-ret);
> >- ret = xsk_ring_prod__reserve(&xsk->tx, rcvd, &idx_tx);
> >- }
> >+ }
> >+
> >+ for (i = 0; i < rcvd; i++) {
> >+ u64 addr = xsk_ring_cons__rx_desc(&xsk->rx,
> >+ idx_rx)->addr;
> >+ u32 len = xsk_ring_cons__rx_desc(&xsk->rx,
> >+ idx_rx++)->len;
> >+ char *pkt = xsk_umem__get_data(xsk->umem->buffer, addr);
> >
> >- for (i = 0; i < rcvd; i++) {
> >- u64 addr = xsk_ring_cons__rx_desc(&xsk->rx,
> >- idx_rx)->addr;
> >- u32 len = xsk_ring_cons__rx_desc(&xsk->rx,
> >- idx_rx++)->len;
> >- char *pkt = xsk_umem__get_data(xsk->umem->buffer, addr);
> >+ swap_mac_addresses(pkt);
> >
> >- swap_mac_addresses(pkt);
> >+ hex_dump(pkt, len, addr);
> >+ xsk_ring_prod__tx_desc(&xsk->tx, idx_tx)->addr = addr;
> >+ xsk_ring_prod__tx_desc(&xsk->tx, idx_tx++)->len = len;
> >+ }
> >
> >- hex_dump(pkt, len, addr);
> >- xsk_ring_prod__tx_desc(&xsk->tx, idx_tx)->addr = addr;
> >- xsk_ring_prod__tx_desc(&xsk->tx, idx_tx++)->len = len;
> >- }
> >+ xsk_ring_prod__submit(&xsk->tx, rcvd);
> >+ xsk_ring_cons__release(&xsk->rx, rcvd);
> >
> >- xsk_ring_prod__submit(&xsk->tx, rcvd);
> >- xsk_ring_cons__release(&xsk->rx, rcvd);
> >+ xsk->rx_npkts += rcvd;
> >+ xsk->outstanding_tx += rcvd;
> >+}
> >
> >- xsk->rx_npkts += rcvd;
> >- xsk->outstanding_tx += rcvd;
> >+static void l2fwd_all(void)
> >+{
> >+ struct pollfd fds[MAX_SOCKS];
> >+ int i, ret;
> >+
> >+ memset(fds, 0, sizeof(fds));
> >+
> >+ for (i = 0; i < num_socks; i++) {
> >+ fds[i].fd = xsk_socket__fd(xsks[i]->xsk);
> >+ fds[i].events = POLLOUT | POLLIN;
> >+ }
> >+
> >+ for (;;) {
> >+ if (opt_poll) {
> >+ ret = poll(fds, num_socks, 0);
> >+ if (ret <= 0)
> >+ continue;
> >+ }
> >+
> >+ for (i = 0; i < num_socks; i++)
> >+ l2fwd(xsks[i], fds);
> > }
> > }
> >
> >@@ -693,9 +740,9 @@ int main(int argc, char **argv)
> > if (opt_bench == BENCH_RXDROP)
> > rx_drop_all();
> > else if (opt_bench == BENCH_TXONLY)
> >- tx_only(xsks[0]);
> >+ tx_only_all();
> > else
> >- l2fwd(xsks[0]);
> >+ l2fwd_all();
> >
> > return 0;
> > }
> >--
> >2.7.4
> >
