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-rw-r--r--samples/bpf/trace_output_user.c43
-rw-r--r--samples/bpf/xdp_fwd_kern.c39
-rw-r--r--samples/bpf/xdp_fwd_user.c35
-rw-r--r--samples/bpf/xdp_sample_pkts_user.c61
4 files changed, 84 insertions, 94 deletions
diff --git a/samples/bpf/trace_output_user.c b/samples/bpf/trace_output_user.c
index 2dd1d39b152a..8ee47699a870 100644
--- a/samples/bpf/trace_output_user.c
+++ b/samples/bpf/trace_output_user.c
@@ -18,9 +18,6 @@
#include <libbpf.h>
#include "bpf_load.h"
#include "perf-sys.h"
-#include "trace_helpers.h"
-
-static int pmu_fd;
static __u64 time_get_ns(void)
{
@@ -31,12 +28,12 @@ static __u64 time_get_ns(void)
}
static __u64 start_time;
+static __u64 cnt;
#define MAX_CNT 100000ll
-static int print_bpf_output(void *data, int size)
+static void print_bpf_output(void *ctx, int cpu, void *data, __u32 size)
{
- static __u64 cnt;
struct {
__u64 pid;
__u64 cookie;
@@ -45,7 +42,7 @@ static int print_bpf_output(void *data, int size)
if (e->cookie != 0x12345678) {
printf("BUG pid %llx cookie %llx sized %d\n",
e->pid, e->cookie, size);
- return LIBBPF_PERF_EVENT_ERROR;
+ return;
}
cnt++;
@@ -53,30 +50,14 @@ static int print_bpf_output(void *data, int size)
if (cnt == MAX_CNT) {
printf("recv %lld events per sec\n",
MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
- return LIBBPF_PERF_EVENT_DONE;
+ return;
}
-
- return LIBBPF_PERF_EVENT_CONT;
-}
-
-static void test_bpf_perf_event(void)
-{
- struct perf_event_attr attr = {
- .sample_type = PERF_SAMPLE_RAW,
- .type = PERF_TYPE_SOFTWARE,
- .config = PERF_COUNT_SW_BPF_OUTPUT,
- };
- int key = 0;
-
- pmu_fd = sys_perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0);
-
- assert(pmu_fd >= 0);
- assert(bpf_map_update_elem(map_fd[0], &key, &pmu_fd, BPF_ANY) == 0);
- ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
}
int main(int argc, char **argv)
{
+ struct perf_buffer_opts pb_opts = {};
+ struct perf_buffer *pb;
char filename[256];
FILE *f;
int ret;
@@ -88,16 +69,20 @@ int main(int argc, char **argv)
return 1;
}
- test_bpf_perf_event();
-
- if (perf_event_mmap(pmu_fd) < 0)
+ pb_opts.sample_cb = print_bpf_output;
+ pb = perf_buffer__new(map_fd[0], 8, &pb_opts);
+ ret = libbpf_get_error(pb);
+ if (ret) {
+ printf("failed to setup perf_buffer: %d\n", ret);
return 1;
+ }
f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");
(void) f;
start_time = time_get_ns();
- ret = perf_event_poller(pmu_fd, print_bpf_output);
+ while ((ret = perf_buffer__poll(pb, 1000)) >= 0 && cnt < MAX_CNT) {
+ }
kill(0, SIGINT);
return ret;
}
diff --git a/samples/bpf/xdp_fwd_kern.c b/samples/bpf/xdp_fwd_kern.c
index a7e94e7ff87d..701a30f258b1 100644
--- a/samples/bpf/xdp_fwd_kern.c
+++ b/samples/bpf/xdp_fwd_kern.c
@@ -23,7 +23,8 @@
#define IPV6_FLOWINFO_MASK cpu_to_be32(0x0FFFFFFF)
-struct bpf_map_def SEC("maps") tx_port = {
+/* For TX-traffic redirect requires net_device ifindex to be in this devmap */
+struct bpf_map_def SEC("maps") xdp_tx_ports = {
.type = BPF_MAP_TYPE_DEVMAP,
.key_size = sizeof(int),
.value_size = sizeof(int),
@@ -102,14 +103,34 @@ static __always_inline int xdp_fwd_flags(struct xdp_md *ctx, u32 flags)
fib_params.ifindex = ctx->ingress_ifindex;
rc = bpf_fib_lookup(ctx, &fib_params, sizeof(fib_params), flags);
-
- /* verify egress index has xdp support
- * TO-DO bpf_map_lookup_elem(&tx_port, &key) fails with
- * cannot pass map_type 14 into func bpf_map_lookup_elem#1:
- * NOTE: without verification that egress index supports XDP
- * forwarding packets are dropped.
+ /*
+ * Some rc (return codes) from bpf_fib_lookup() are important,
+ * to understand how this XDP-prog interacts with network stack.
+ *
+ * BPF_FIB_LKUP_RET_NO_NEIGH:
+ * Even if route lookup was a success, then the MAC-addresses are also
+ * needed. This is obtained from arp/neighbour table, but if table is
+ * (still) empty then BPF_FIB_LKUP_RET_NO_NEIGH is returned. To avoid
+ * doing ARP lookup directly from XDP, then send packet to normal
+ * network stack via XDP_PASS and expect it will do ARP resolution.
+ *
+ * BPF_FIB_LKUP_RET_FWD_DISABLED:
+ * The bpf_fib_lookup respect sysctl net.ipv{4,6}.conf.all.forwarding
+ * setting, and will return BPF_FIB_LKUP_RET_FWD_DISABLED if not
+ * enabled this on ingress device.
*/
- if (rc == 0) {
+ if (rc == BPF_FIB_LKUP_RET_SUCCESS) {
+ /* Verify egress index has been configured as TX-port.
+ * (Note: User can still have inserted an egress ifindex that
+ * doesn't support XDP xmit, which will result in packet drops).
+ *
+ * Note: lookup in devmap supported since 0cdbb4b09a0.
+ * If not supported will fail with:
+ * cannot pass map_type 14 into func bpf_map_lookup_elem#1:
+ */
+ if (!bpf_map_lookup_elem(&xdp_tx_ports, &fib_params.ifindex))
+ return XDP_PASS;
+
if (h_proto == htons(ETH_P_IP))
ip_decrease_ttl(iph);
else if (h_proto == htons(ETH_P_IPV6))
@@ -117,7 +138,7 @@ static __always_inline int xdp_fwd_flags(struct xdp_md *ctx, u32 flags)
memcpy(eth->h_dest, fib_params.dmac, ETH_ALEN);
memcpy(eth->h_source, fib_params.smac, ETH_ALEN);
- return bpf_redirect_map(&tx_port, fib_params.ifindex, 0);
+ return bpf_redirect_map(&xdp_tx_ports, fib_params.ifindex, 0);
}
return XDP_PASS;
diff --git a/samples/bpf/xdp_fwd_user.c b/samples/bpf/xdp_fwd_user.c
index 5b46ee12c696..97ff1dad7669 100644
--- a/samples/bpf/xdp_fwd_user.c
+++ b/samples/bpf/xdp_fwd_user.c
@@ -27,14 +27,20 @@
#include "libbpf.h"
#include <bpf/bpf.h>
-
-static int do_attach(int idx, int fd, const char *name)
+static int do_attach(int idx, int prog_fd, int map_fd, const char *name)
{
int err;
- err = bpf_set_link_xdp_fd(idx, fd, 0);
- if (err < 0)
+ err = bpf_set_link_xdp_fd(idx, prog_fd, 0);
+ if (err < 0) {
printf("ERROR: failed to attach program to %s\n", name);
+ return err;
+ }
+
+ /* Adding ifindex as a possible egress TX port */
+ err = bpf_map_update_elem(map_fd, &idx, &idx, 0);
+ if (err)
+ printf("ERROR: failed using device %s as TX-port\n", name);
return err;
}
@@ -47,6 +53,9 @@ static int do_detach(int idx, const char *name)
if (err < 0)
printf("ERROR: failed to detach program from %s\n", name);
+ /* TODO: Remember to cleanup map, when adding use of shared map
+ * bpf_map_delete_elem((map_fd, &idx);
+ */
return err;
}
@@ -67,10 +76,10 @@ int main(int argc, char **argv)
};
const char *prog_name = "xdp_fwd";
struct bpf_program *prog;
+ int prog_fd, map_fd = -1;
char filename[PATH_MAX];
struct bpf_object *obj;
int opt, i, idx, err;
- int prog_fd, map_fd;
int attach = 1;
int ret = 0;
@@ -103,8 +112,14 @@ int main(int argc, char **argv)
return 1;
}
- if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
+ err = bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd);
+ if (err) {
+ printf("Does kernel support devmap lookup?\n");
+ /* If not, the error message will be:
+ * "cannot pass map_type 14 into func bpf_map_lookup_elem#1"
+ */
return 1;
+ }
prog = bpf_object__find_program_by_title(obj, prog_name);
prog_fd = bpf_program__fd(prog);
@@ -113,16 +128,12 @@ int main(int argc, char **argv)
return 1;
}
map_fd = bpf_map__fd(bpf_object__find_map_by_name(obj,
- "tx_port"));
+ "xdp_tx_ports"));
if (map_fd < 0) {
printf("map not found: %s\n", strerror(map_fd));
return 1;
}
}
- if (attach) {
- for (i = 1; i < 64; ++i)
- bpf_map_update_elem(map_fd, &i, &i, 0);
- }
for (i = optind; i < argc; ++i) {
idx = if_nametoindex(argv[i]);
@@ -138,7 +149,7 @@ int main(int argc, char **argv)
if (err)
ret = err;
} else {
- err = do_attach(idx, prog_fd, argv[i]);
+ err = do_attach(idx, prog_fd, map_fd, argv[i]);
if (err)
ret = err;
}
diff --git a/samples/bpf/xdp_sample_pkts_user.c b/samples/bpf/xdp_sample_pkts_user.c
index dc66345a929a..3002714e3cd5 100644
--- a/samples/bpf/xdp_sample_pkts_user.c
+++ b/samples/bpf/xdp_sample_pkts_user.c
@@ -17,14 +17,13 @@
#include <linux/if_link.h>
#include "perf-sys.h"
-#include "trace_helpers.h"
#define MAX_CPUS 128
-static int pmu_fds[MAX_CPUS], if_idx;
-static struct perf_event_mmap_page *headers[MAX_CPUS];
+static int if_idx;
static char *if_name;
static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
static __u32 prog_id;
+static struct perf_buffer *pb = NULL;
static int do_attach(int idx, int fd, const char *name)
{
@@ -73,7 +72,7 @@ static int do_detach(int idx, const char *name)
#define SAMPLE_SIZE 64
-static int print_bpf_output(void *data, int size)
+static void print_bpf_output(void *ctx, int cpu, void *data, __u32 size)
{
struct {
__u16 cookie;
@@ -83,45 +82,20 @@ static int print_bpf_output(void *data, int size)
int i;
if (e->cookie != 0xdead) {
- printf("BUG cookie %x sized %d\n",
- e->cookie, size);
- return LIBBPF_PERF_EVENT_ERROR;
+ printf("BUG cookie %x sized %d\n", e->cookie, size);
+ return;
}
printf("Pkt len: %-5d bytes. Ethernet hdr: ", e->pkt_len);
for (i = 0; i < 14 && i < e->pkt_len; i++)
printf("%02x ", e->pkt_data[i]);
printf("\n");
-
- return LIBBPF_PERF_EVENT_CONT;
-}
-
-static void test_bpf_perf_event(int map_fd, int num)
-{
- struct perf_event_attr attr = {
- .sample_type = PERF_SAMPLE_RAW,
- .type = PERF_TYPE_SOFTWARE,
- .config = PERF_COUNT_SW_BPF_OUTPUT,
- .wakeup_events = 1, /* get an fd notification for every event */
- };
- int i;
-
- for (i = 0; i < num; i++) {
- int key = i;
-
- pmu_fds[i] = sys_perf_event_open(&attr, -1/*pid*/, i/*cpu*/,
- -1/*group_fd*/, 0);
-
- assert(pmu_fds[i] >= 0);
- assert(bpf_map_update_elem(map_fd, &key,
- &pmu_fds[i], BPF_ANY) == 0);
- ioctl(pmu_fds[i], PERF_EVENT_IOC_ENABLE, 0);
- }
}
static void sig_handler(int signo)
{
do_detach(if_idx, if_name);
+ perf_buffer__free(pb);
exit(0);
}
@@ -140,13 +114,13 @@ int main(int argc, char **argv)
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
+ struct perf_buffer_opts pb_opts = {};
const char *optstr = "F";
int prog_fd, map_fd, opt;
struct bpf_object *obj;
struct bpf_map *map;
char filename[256];
- int ret, err, i;
- int numcpus;
+ int ret, err;
while ((opt = getopt(argc, argv, optstr)) != -1) {
switch (opt) {
@@ -169,10 +143,6 @@ int main(int argc, char **argv)
return 1;
}
- numcpus = get_nprocs();
- if (numcpus > MAX_CPUS)
- numcpus = MAX_CPUS;
-
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
prog_load_attr.file = filename;
@@ -211,14 +181,17 @@ int main(int argc, char **argv)
return 1;
}
- test_bpf_perf_event(map_fd, numcpus);
+ pb_opts.sample_cb = print_bpf_output;
+ pb = perf_buffer__new(map_fd, 8, &pb_opts);
+ err = libbpf_get_error(pb);
+ if (err) {
+ perror("perf_buffer setup failed");
+ return 1;
+ }
- for (i = 0; i < numcpus; i++)
- if (perf_event_mmap_header(pmu_fds[i], &headers[i]) < 0)
- return 1;
+ while ((ret = perf_buffer__poll(pb, 1000)) >= 0) {
+ }
- ret = perf_event_poller_multi(pmu_fds, headers, numcpus,
- print_bpf_output);
kill(0, SIGINT);
return ret;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 05:39:24 +0000