diff options
Diffstat (limited to 'samples')
| -rw-r--r-- | samples/bpf/Makefile | 4 | ||||
| -rw-r--r-- | samples/bpf/xdp_rxq_info_kern.c | 43 | ||||
| -rw-r--r-- | samples/bpf/xdp_rxq_info_user.c | 45 | ||||
| -rw-r--r-- | samples/bpf/xdp_sample_pkts_kern.c | 66 | ||||
| -rw-r--r-- | samples/bpf/xdp_sample_pkts_user.c | 169 |
5 files changed, 321 insertions, 6 deletions
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 1303af10e54d..9ea2f7b64869 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -52,6 +52,7 @@ hostprogs-y += xdp_adjust_tail hostprogs-y += xdpsock hostprogs-y += xdp_fwd hostprogs-y += task_fd_query +hostprogs-y += xdp_sample_pkts # Libbpf dependencies LIBBPF = $(TOOLS_PATH)/lib/bpf/libbpf.a @@ -107,6 +108,7 @@ xdp_adjust_tail-objs := xdp_adjust_tail_user.o xdpsock-objs := bpf_load.o xdpsock_user.o xdp_fwd-objs := bpf_load.o xdp_fwd_user.o task_fd_query-objs := bpf_load.o task_fd_query_user.o $(TRACE_HELPERS) +xdp_sample_pkts-objs := xdp_sample_pkts_user.o $(TRACE_HELPERS) # Tell kbuild to always build the programs always := $(hostprogs-y) @@ -163,6 +165,7 @@ always += xdp_adjust_tail_kern.o always += xdpsock_kern.o always += xdp_fwd_kern.o always += task_fd_query_kern.o +always += xdp_sample_pkts_kern.o HOSTCFLAGS += -I$(objtree)/usr/include HOSTCFLAGS += -I$(srctree)/tools/lib/ @@ -179,6 +182,7 @@ HOSTCFLAGS_spintest_user.o += -I$(srctree)/tools/lib/bpf/ HOSTCFLAGS_trace_event_user.o += -I$(srctree)/tools/lib/bpf/ HOSTCFLAGS_sampleip_user.o += -I$(srctree)/tools/lib/bpf/ HOSTCFLAGS_task_fd_query_user.o += -I$(srctree)/tools/lib/bpf/ +HOSTCFLAGS_xdp_sample_pkts_user.o += -I$(srctree)/tools/lib/bpf/ HOST_LOADLIBES += $(LIBBPF) -lelf HOSTLOADLIBES_tracex4 += -lrt diff --git a/samples/bpf/xdp_rxq_info_kern.c b/samples/bpf/xdp_rxq_info_kern.c index 3fd209291653..222a83eed1cb 100644 --- a/samples/bpf/xdp_rxq_info_kern.c +++ b/samples/bpf/xdp_rxq_info_kern.c @@ -4,6 +4,8 @@ * Example howto extract XDP RX-queue info */ #include <uapi/linux/bpf.h> +#include <uapi/linux/if_ether.h> +#include <uapi/linux/in.h> #include "bpf_helpers.h" /* Config setup from with userspace @@ -14,6 +16,12 @@ struct config { __u32 action; int ifindex; + __u32 options; +}; +enum cfg_options_flags { + NO_TOUCH = 0x0U, + READ_MEM = 0x1U, + SWAP_MAC = 0x2U, }; struct bpf_map_def SEC("maps") config_map = { .type = BPF_MAP_TYPE_ARRAY, @@ -45,6 +53,23 @@ struct bpf_map_def SEC("maps") rx_queue_index_map = { .max_entries = MAX_RXQs + 1, }; +static __always_inline +void swap_src_dst_mac(void *data) +{ + unsigned short *p = data; + unsigned short dst[3]; + + dst[0] = p[0]; + dst[1] = p[1]; + dst[2] = p[2]; + p[0] = p[3]; + p[1] = p[4]; + p[2] = p[5]; + p[3] = dst[0]; + p[4] = dst[1]; + p[5] = dst[2]; +} + SEC("xdp_prog0") int xdp_prognum0(struct xdp_md *ctx) { @@ -90,6 +115,24 @@ int xdp_prognum0(struct xdp_md *ctx) if (key == MAX_RXQs) rxq_rec->issue++; + /* Default: Don't touch packet data, only count packets */ + if (unlikely(config->options & (READ_MEM|SWAP_MAC))) { + struct ethhdr *eth = data; + + if (eth + 1 > data_end) + return XDP_ABORTED; + + /* Avoid compiler removing this: Drop non 802.3 Ethertypes */ + if (ntohs(eth->h_proto) < ETH_P_802_3_MIN) + return XDP_ABORTED; + + /* XDP_TX requires changing MAC-addrs, else HW may drop. + * Can also be enabled with --swapmac (for test purposes) + */ + if (unlikely(config->options & SWAP_MAC)) + swap_src_dst_mac(data); + } + return config->action; } diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c index e4e9ba52bff0..248a7eab9531 100644 --- a/samples/bpf/xdp_rxq_info_user.c +++ b/samples/bpf/xdp_rxq_info_user.c @@ -50,6 +50,8 @@ static const struct option long_options[] = { {"sec", required_argument, NULL, 's' }, {"no-separators", no_argument, NULL, 'z' }, {"action", required_argument, NULL, 'a' }, + {"readmem", no_argument, NULL, 'r' }, + {"swapmac", no_argument, NULL, 'm' }, {0, 0, NULL, 0 } }; @@ -66,6 +68,12 @@ static void int_exit(int sig) struct config { __u32 action; int ifindex; + __u32 options; +}; +enum cfg_options_flags { + NO_TOUCH = 0x0U, + READ_MEM = 0x1U, + SWAP_MAC = 0x2U, }; #define XDP_ACTION_MAX (XDP_TX + 1) #define XDP_ACTION_MAX_STRLEN 11 @@ -109,6 +117,18 @@ static void list_xdp_actions(void) printf("\n"); } +static char* options2str(enum cfg_options_flags flag) +{ + if (flag == NO_TOUCH) + return "no_touch"; + if (flag & SWAP_MAC) + return "swapmac"; + if (flag & READ_MEM) + return "read"; + fprintf(stderr, "ERR: Unknown config option flags"); + exit(EXIT_FAIL); +} + static void usage(char *argv[]) { int i; @@ -305,7 +325,7 @@ static __u64 calc_errs_pps(struct datarec *r, static void stats_print(struct stats_record *stats_rec, struct stats_record *stats_prev, - int action) + int action, __u32 cfg_opt) { unsigned int nr_rxqs = bpf_map__def(rx_queue_index_map)->max_entries; unsigned int nr_cpus = bpf_num_possible_cpus(); @@ -316,8 +336,8 @@ static void stats_print(struct stats_record *stats_rec, int i; /* Header */ - printf("\nRunning XDP on dev:%s (ifindex:%d) action:%s\n", - ifname, ifindex, action2str(action)); + printf("\nRunning XDP on dev:%s (ifindex:%d) action:%s options:%s\n", + ifname, ifindex, action2str(action), options2str(cfg_opt)); /* stats_global_map */ { @@ -399,7 +419,7 @@ static inline void swap(struct stats_record **a, struct stats_record **b) *b = tmp; } -static void stats_poll(int interval, int action) +static void stats_poll(int interval, int action, __u32 cfg_opt) { struct stats_record *record, *prev; @@ -410,7 +430,7 @@ static void stats_poll(int interval, int action) while (1) { swap(&prev, &record); stats_collect(record); - stats_print(record, prev, action); + stats_print(record, prev, action, cfg_opt); sleep(interval); } @@ -421,6 +441,7 @@ static void stats_poll(int interval, int action) int main(int argc, char **argv) { + __u32 cfg_options= NO_TOUCH ; /* Default: Don't touch packet memory */ struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY}; struct bpf_prog_load_attr prog_load_attr = { .prog_type = BPF_PROG_TYPE_XDP, @@ -435,6 +456,7 @@ int main(int argc, char **argv) int interval = 2; __u32 key = 0; + char action_str_buf[XDP_ACTION_MAX_STRLEN + 1 /* for \0 */] = { 0 }; int action = XDP_PASS; /* Default action */ char *action_str = NULL; @@ -496,6 +518,12 @@ int main(int argc, char **argv) action_str = (char *)&action_str_buf; strncpy(action_str, optarg, XDP_ACTION_MAX_STRLEN); break; + case 'r': + cfg_options |= READ_MEM; + break; + case 'm': + cfg_options |= SWAP_MAC; + break; case 'h': error: default: @@ -523,6 +551,11 @@ int main(int argc, char **argv) } cfg.action = action; + /* XDP_TX requires changing MAC-addrs, else HW may drop */ + if (action == XDP_TX) + cfg_options |= SWAP_MAC; + cfg.options = cfg_options; + /* Trick to pretty printf with thousands separators use %' */ if (use_separators) setlocale(LC_NUMERIC, "en_US"); @@ -542,6 +575,6 @@ int main(int argc, char **argv) return EXIT_FAIL_XDP; } - stats_poll(interval, action); + stats_poll(interval, action, cfg_options); return EXIT_OK; } diff --git a/samples/bpf/xdp_sample_pkts_kern.c b/samples/bpf/xdp_sample_pkts_kern.c new file mode 100644 index 000000000000..f7ca8b850978 --- /dev/null +++ b/samples/bpf/xdp_sample_pkts_kern.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/ptrace.h> +#include <linux/version.h> +#include <uapi/linux/bpf.h> +#include "bpf_helpers.h" + +#define SAMPLE_SIZE 64ul +#define MAX_CPUS 128 + +#define bpf_printk(fmt, ...) \ +({ \ + char ____fmt[] = fmt; \ + bpf_trace_printk(____fmt, sizeof(____fmt), \ + ##__VA_ARGS__); \ +}) + +struct bpf_map_def SEC("maps") my_map = { + .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY, + .key_size = sizeof(int), + .value_size = sizeof(u32), + .max_entries = MAX_CPUS, +}; + +SEC("xdp_sample") +int xdp_sample_prog(struct xdp_md *ctx) +{ + void *data_end = (void *)(long)ctx->data_end; + void *data = (void *)(long)ctx->data; + + /* Metadata will be in the perf event before the packet data. */ + struct S { + u16 cookie; + u16 pkt_len; + } __packed metadata; + + if (data < data_end) { + /* The XDP perf_event_output handler will use the upper 32 bits + * of the flags argument as a number of bytes to include of the + * packet payload in the event data. If the size is too big, the + * call to bpf_perf_event_output will fail and return -EFAULT. + * + * See bpf_xdp_event_output in net/core/filter.c. + * + * The BPF_F_CURRENT_CPU flag means that the event output fd + * will be indexed by the CPU number in the event map. + */ + u64 flags = BPF_F_CURRENT_CPU; + u16 sample_size; + int ret; + + metadata.cookie = 0xdead; + metadata.pkt_len = (u16)(data_end - data); + sample_size = min(metadata.pkt_len, SAMPLE_SIZE); + flags |= (u64)sample_size << 32; + + ret = bpf_perf_event_output(ctx, &my_map, flags, + &metadata, sizeof(metadata)); + if (ret) + bpf_printk("perf_event_output failed: %d\n", ret); + } + + return XDP_PASS; +} + +char _license[] SEC("license") = "GPL"; +u32 _version SEC("version") = LINUX_VERSION_CODE; diff --git a/samples/bpf/xdp_sample_pkts_user.c b/samples/bpf/xdp_sample_pkts_user.c new file mode 100644 index 000000000000..8dd87c1eb560 --- /dev/null +++ b/samples/bpf/xdp_sample_pkts_user.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <linux/perf_event.h> +#include <linux/bpf.h> +#include <net/if.h> +#include <errno.h> +#include <assert.h> +#include <sys/sysinfo.h> +#include <sys/ioctl.h> +#include <signal.h> +#include <libbpf.h> +#include <bpf/bpf.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 char *if_name; + +static int do_attach(int idx, int fd, const char *name) +{ + int err; + + err = bpf_set_link_xdp_fd(idx, fd, 0); + if (err < 0) + printf("ERROR: failed to attach program to %s\n", name); + + return err; +} + +static int do_detach(int idx, const char *name) +{ + int err; + + err = bpf_set_link_xdp_fd(idx, -1, 0); + if (err < 0) + printf("ERROR: failed to detach program from %s\n", name); + + return err; +} + +#define SAMPLE_SIZE 64 + +static int print_bpf_output(void *data, int size) +{ + struct { + __u16 cookie; + __u16 pkt_len; + __u8 pkt_data[SAMPLE_SIZE]; + } __packed *e = data; + int i; + + if (e->cookie != 0xdead) { + printf("BUG cookie %x sized %d\n", + e->cookie, size); + return LIBBPF_PERF_EVENT_ERROR; + } + + 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); + exit(0); +} + +int main(int argc, char **argv) +{ + struct bpf_prog_load_attr prog_load_attr = { + .prog_type = BPF_PROG_TYPE_XDP, + }; + struct bpf_object *obj; + struct bpf_map *map; + int prog_fd, map_fd; + char filename[256]; + int ret, err, i; + int numcpus; + + if (argc < 2) { + printf("Usage: %s <ifname>\n", argv[0]); + 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; + + if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd)) + return 1; + + if (!prog_fd) { + printf("load_bpf_file: %s\n", strerror(errno)); + return 1; + } + + map = bpf_map__next(NULL, obj); + if (!map) { + printf("finding a map in obj file failed\n"); + return 1; + } + map_fd = bpf_map__fd(map); + + if_idx = if_nametoindex(argv[1]); + if (!if_idx) + if_idx = strtoul(argv[1], NULL, 0); + + if (!if_idx) { + fprintf(stderr, "Invalid ifname\n"); + return 1; + } + if_name = argv[1]; + err = do_attach(if_idx, prog_fd, argv[1]); + if (err) + return err; + + if (signal(SIGINT, sig_handler) || + signal(SIGHUP, sig_handler) || + signal(SIGTERM, sig_handler)) { + perror("signal"); + return 1; + } + + test_bpf_perf_event(map_fd, numcpus); + + for (i = 0; i < numcpus; i++) + if (perf_event_mmap_header(pmu_fds[i], &headers[i]) < 0) + return 1; + + ret = perf_event_poller_multi(pmu_fds, headers, numcpus, + print_bpf_output); + kill(0, SIGINT); + return ret; +} |