samples, bpf: Move routes monitor in xdp_router_ipv4 in a dedicated thread

In order to not miss any netlink message from the kernel, move routes
monitor to a dedicated thread.

Fixes: 85bf1f5169 ("samples: bpf: Convert xdp_router_ipv4 to XDP samples helper")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/e364b817c69ded73be24b677ab47a157f7c21b64.1649167911.git.lorenzo@kernel.org
This commit is contained in:
Lorenzo Bianconi 2022-04-05 16:15:14 +02:00 committed by Daniel Borkmann
parent 3a06ec0a99
commit 587323cf6a
2 changed files with 61 additions and 39 deletions

View File

@ -219,7 +219,7 @@ TPROGLDLIBS_xdp_redirect += -lm
TPROGLDLIBS_xdp_redirect_cpu += -lm
TPROGLDLIBS_xdp_redirect_map += -lm
TPROGLDLIBS_xdp_redirect_map_multi += -lm
TPROGLDLIBS_xdp_router_ipv4 += -lm
TPROGLDLIBS_xdp_router_ipv4 += -lm -pthread
TPROGLDLIBS_tracex4 += -lrt
TPROGLDLIBS_trace_output += -lrt
TPROGLDLIBS_map_perf_test += -lrt

View File

@ -25,6 +25,7 @@
#include <sys/resource.h>
#include <libgen.h>
#include <getopt.h>
#include <pthread.h>
#include "xdp_sample_user.h"
#include "xdp_router_ipv4.skel.h"
@ -38,6 +39,9 @@ static int arp_table_map_fd;
static int exact_match_map_fd;
static int tx_port_map_fd;
static bool routes_thread_exit;
static int interval = 5;
static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_MAP_CNT |
SAMPLE_DEVMAP_XMIT_CNT_MULTI | SAMPLE_EXCEPTION_CNT;
@ -445,7 +449,7 @@ cleanup:
/* Function to keep track and update changes in route and arp table
* Give regular statistics of packets forwarded
*/
static void monitor_route(void *ctx)
static void *monitor_routes_thread(void *arg)
{
struct pollfd fds_route, fds_arp;
struct sockaddr_nl la, lr;
@ -455,7 +459,7 @@ static void monitor_route(void *ctx)
sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (sock < 0) {
fprintf(stderr, "open netlink socket: %s\n", strerror(errno));
return;
return NULL;
}
fcntl(sock, F_SETFL, O_NONBLOCK);
@ -465,7 +469,7 @@ static void monitor_route(void *ctx)
if (bind(sock, (struct sockaddr *)&lr, sizeof(lr)) < 0) {
fprintf(stderr, "bind netlink socket: %s\n", strerror(errno));
close(sock);
return;
return NULL;
}
fds_route.fd = sock;
@ -475,7 +479,7 @@ static void monitor_route(void *ctx)
if (sock_arp < 0) {
fprintf(stderr, "open netlink socket: %s\n", strerror(errno));
close(sock);
return;
return NULL;
}
fcntl(sock_arp, F_SETFL, O_NONBLOCK);
@ -490,35 +494,51 @@ static void monitor_route(void *ctx)
fds_arp.fd = sock_arp;
fds_arp.events = POLL_IN;
memset(buf, 0, sizeof(buf));
if (poll(&fds_route, 1, 3) == POLL_IN) {
nll = recv_msg(lr, sock);
if (nll < 0) {
fprintf(stderr, "recv from netlink: %s\n",
strerror(nll));
goto cleanup;
}
nh = (struct nlmsghdr *)buf;
read_route(nh, nll);
/* dump route and arp tables */
if (get_arp_table(AF_INET) < 0) {
fprintf(stderr, "Failed reading arp table\n");
goto cleanup;
}
memset(buf, 0, sizeof(buf));
if (poll(&fds_arp, 1, 3) == POLL_IN) {
nll = recv_msg(la, sock_arp);
if (nll < 0) {
fprintf(stderr, "recv from netlink: %s\n",
strerror(nll));
goto cleanup;
if (get_route_table(AF_INET) < 0) {
fprintf(stderr, "Failed reading route table\n");
goto cleanup;
}
while (!routes_thread_exit) {
memset(buf, 0, sizeof(buf));
if (poll(&fds_route, 1, 3) == POLL_IN) {
nll = recv_msg(lr, sock);
if (nll < 0) {
fprintf(stderr, "recv from netlink: %s\n",
strerror(nll));
goto cleanup;
}
nh = (struct nlmsghdr *)buf;
read_route(nh, nll);
}
nh = (struct nlmsghdr *)buf;
read_arp(nh, nll);
memset(buf, 0, sizeof(buf));
if (poll(&fds_arp, 1, 3) == POLL_IN) {
nll = recv_msg(la, sock_arp);
if (nll < 0) {
fprintf(stderr, "recv from netlink: %s\n",
strerror(nll));
goto cleanup;
}
nh = (struct nlmsghdr *)buf;
read_arp(nh, nll);
}
sleep(interval);
}
cleanup:
close(sock_arp);
close(sock);
return NULL;
}
static void usage(char *argv[], const struct option *long_options,
@ -531,10 +551,11 @@ static void usage(char *argv[], const struct option *long_options,
int main(int argc, char **argv)
{
bool error = true, generic = false, force = false;
int opt, interval = 5, ret = EXIT_FAIL_BPF;
int opt, ret = EXIT_FAIL_BPF;
struct xdp_router_ipv4 *skel;
int i, total_ifindex = argc - 1;
char **ifname_list = argv + 1;
pthread_t routes_thread;
int longindex = 0;
if (libbpf_set_strict_mode(LIBBPF_STRICT_ALL) < 0) {
@ -653,24 +674,25 @@ int main(int argc, char **argv)
goto end_destroy;
}
if (get_route_table(AF_INET) < 0) {
fprintf(stderr, "Failed reading routing table\n");
goto end_destroy;
}
if (get_arp_table(AF_INET) < 0) {
fprintf(stderr, "Failed reading arptable\n");
goto end_destroy;
}
ret = sample_run(interval, monitor_route, NULL);
if (ret < 0) {
fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret));
ret = pthread_create(&routes_thread, NULL, monitor_routes_thread, NULL);
if (ret) {
fprintf(stderr, "Failed creating routes_thread: %s\n", strerror(-ret));
ret = EXIT_FAIL;
goto end_destroy;
}
ret = sample_run(interval, NULL, NULL);
routes_thread_exit = true;
if (ret < 0) {
fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret));
ret = EXIT_FAIL;
goto end_thread_wait;
}
ret = EXIT_OK;
end_thread_wait:
pthread_join(routes_thread, NULL);
end_destroy:
xdp_router_ipv4__destroy(skel);
end: