linux/samples/bpf/xdp_monitor_user.c

363 lines
7.9 KiB
C

/* Copyright(c) 2017 Jesper Dangaard Brouer, Red Hat, Inc.
*/
static const char *__doc__=
"XDP monitor tool, based on tracepoints\n"
;
static const char *__doc_err_only__=
" NOTICE: Only tracking XDP redirect errors\n"
" Enable TX success stats via '--stats'\n"
" (which comes with a per packet processing overhead)\n"
;
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <locale.h>
#include <sys/resource.h>
#include <getopt.h>
#include <net/if.h>
#include <time.h>
#include "libbpf.h"
#include "bpf_load.h"
#include "bpf_util.h"
static int verbose = 1;
static bool debug = false;
static const struct option long_options[] = {
{"help", no_argument, NULL, 'h' },
{"debug", no_argument, NULL, 'D' },
{"stats", no_argument, NULL, 'S' },
{"sec", required_argument, NULL, 's' },
{0, 0, NULL, 0 }
};
static void usage(char *argv[])
{
int i;
printf("\nDOCUMENTATION:\n%s\n", __doc__);
printf("\n");
printf(" Usage: %s (options-see-below)\n",
argv[0]);
printf(" Listing options:\n");
for (i = 0; long_options[i].name != 0; i++) {
printf(" --%-15s", long_options[i].name);
if (long_options[i].flag != NULL)
printf(" flag (internal value:%d)",
*long_options[i].flag);
else
printf("(internal short-option: -%c)",
long_options[i].val);
printf("\n");
}
printf("\n");
}
#define NANOSEC_PER_SEC 1000000000 /* 10^9 */
static __u64 gettime(void)
{
struct timespec t;
int res;
res = clock_gettime(CLOCK_MONOTONIC, &t);
if (res < 0) {
fprintf(stderr, "Error with gettimeofday! (%i)\n", res);
exit(EXIT_FAILURE);
}
return (__u64) t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec;
}
enum {
REDIR_SUCCESS = 0,
REDIR_ERROR = 1,
};
#define REDIR_RES_MAX 2
static const char *redir_names[REDIR_RES_MAX] = {
[REDIR_SUCCESS] = "Success",
[REDIR_ERROR] = "Error",
};
static const char *err2str(int err)
{
if (err < REDIR_RES_MAX)
return redir_names[err];
return NULL;
}
/* enum xdp_action */
#define XDP_UNKNOWN XDP_REDIRECT + 1
#define XDP_ACTION_MAX (XDP_UNKNOWN + 1)
static const char *xdp_action_names[XDP_ACTION_MAX] = {
[XDP_ABORTED] = "XDP_ABORTED",
[XDP_DROP] = "XDP_DROP",
[XDP_PASS] = "XDP_PASS",
[XDP_TX] = "XDP_TX",
[XDP_REDIRECT] = "XDP_REDIRECT",
[XDP_UNKNOWN] = "XDP_UNKNOWN",
};
static const char *action2str(int action)
{
if (action < XDP_ACTION_MAX)
return xdp_action_names[action];
return NULL;
}
struct record {
__u64 counter;
__u64 timestamp;
};
struct stats_record {
struct record xdp_redir[REDIR_RES_MAX];
struct record xdp_exception[XDP_ACTION_MAX];
};
static void stats_print_headers(bool err_only)
{
if (err_only)
printf("\n%s\n", __doc_err_only__);
printf("%-14s %-11s %-10s %-18s %-9s\n",
"ACTION", "result", "pps ", "pps-human-readable", "measure-period");
}
static double calc_period(struct record *r, struct record *p)
{
double period_ = 0;
__u64 period = 0;
period = r->timestamp - p->timestamp;
if (period > 0)
period_ = ((double) period / NANOSEC_PER_SEC);
return period_;
}
static double calc_pps(struct record *r, struct record *p, double period)
{
__u64 packets = 0;
double pps = 0;
if (period > 0) {
packets = r->counter - p->counter;
pps = packets / period;
}
return pps;
}
static void stats_print(struct stats_record *rec,
struct stats_record *prev,
bool err_only)
{
double period = 0, pps = 0;
struct record *r, *p;
int i = 0;
char *fmt = "%-14s %-11s %-10.0f %'-18.0f %f\n";
/* tracepoint: xdp:xdp_redirect_* */
if (err_only)
i = REDIR_ERROR;
for (; i < REDIR_RES_MAX; i++) {
r = &rec->xdp_redir[i];
p = &prev->xdp_redir[i];
if (p->timestamp) {
period = calc_period(r, p);
pps = calc_pps(r, p, period);
}
printf(fmt, "XDP_REDIRECT", err2str(i), pps, pps, period);
}
/* tracepoint: xdp:xdp_exception */
for (i = 0; i < XDP_ACTION_MAX; i++) {
r = &rec->xdp_exception[i];
p = &prev->xdp_exception[i];
if (p->timestamp) {
period = calc_period(r, p);
pps = calc_pps(r, p, period);
}
if (pps > 0)
printf(fmt, action2str(i), "Exception",
pps, pps, period);
}
printf("\n");
}
static __u64 get_key32_value64_percpu(int fd, __u32 key)
{
/* For percpu maps, userspace gets a value per possible CPU */
unsigned int nr_cpus = bpf_num_possible_cpus();
__u64 values[nr_cpus];
__u64 sum = 0;
int i;
if ((bpf_map_lookup_elem(fd, &key, values)) != 0) {
fprintf(stderr,
"ERR: bpf_map_lookup_elem failed key:0x%X\n", key);
return 0;
}
/* Sum values from each CPU */
for (i = 0; i < nr_cpus; i++) {
sum += values[i];
}
return sum;
}
static bool stats_collect(struct stats_record *rec)
{
int fd;
int i;
/* TODO: Detect if someone unloaded the perf event_fd's, as
* this can happen by someone running perf-record -e
*/
fd = map_data[0].fd; /* map0: redirect_err_cnt */
for (i = 0; i < REDIR_RES_MAX; i++) {
rec->xdp_redir[i].timestamp = gettime();
rec->xdp_redir[i].counter = get_key32_value64_percpu(fd, i);
}
fd = map_data[1].fd; /* map1: exception_cnt */
for (i = 0; i < XDP_ACTION_MAX; i++) {
rec->xdp_exception[i].timestamp = gettime();
rec->xdp_exception[i].counter = get_key32_value64_percpu(fd, i);
}
return true;
}
static void stats_poll(int interval, bool err_only)
{
struct stats_record rec, prev;
memset(&rec, 0, sizeof(rec));
/* Trick to pretty printf with thousands separators use %' */
setlocale(LC_NUMERIC, "en_US");
/* Header */
if (verbose)
printf("\n%s", __doc__);
/* TODO Need more advanced stats on error types */
if (verbose) {
printf(" - Stats map0: %s\n", map_data[0].name);
printf(" - Stats map1: %s\n", map_data[1].name);
printf("\n");
}
fflush(stdout);
while (1) {
memcpy(&prev, &rec, sizeof(rec));
stats_collect(&rec);
stats_print_headers(err_only);
stats_print(&rec, &prev, err_only);
fflush(stdout);
sleep(interval);
}
}
static void print_bpf_prog_info(void)
{
int i;
/* Prog info */
printf("Loaded BPF prog have %d bpf program(s)\n", prog_cnt);
for (i = 0; i < prog_cnt; i++) {
printf(" - prog_fd[%d] = fd(%d)\n", i, prog_fd[i]);
}
/* Maps info */
printf("Loaded BPF prog have %d map(s)\n", map_data_count);
for (i = 0; i < map_data_count; i++) {
char *name = map_data[i].name;
int fd = map_data[i].fd;
printf(" - map_data[%d] = fd(%d) name:%s\n", i, fd, name);
}
/* Event info */
printf("Searching for (max:%d) event file descriptor(s)\n", prog_cnt);
for (i = 0; i < prog_cnt; i++) {
if (event_fd[i] != -1)
printf(" - event_fd[%d] = fd(%d)\n", i, event_fd[i]);
}
}
int main(int argc, char **argv)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
int longindex = 0, opt;
int ret = EXIT_SUCCESS;
char bpf_obj_file[256];
/* Default settings: */
bool errors_only = true;
int interval = 2;
snprintf(bpf_obj_file, sizeof(bpf_obj_file), "%s_kern.o", argv[0]);
/* Parse commands line args */
while ((opt = getopt_long(argc, argv, "h",
long_options, &longindex)) != -1) {
switch (opt) {
case 'D':
debug = true;
break;
case 'S':
errors_only = false;
break;
case 's':
interval = atoi(optarg);
break;
case 'h':
default:
usage(argv);
return EXIT_FAILURE;
}
}
if (setrlimit(RLIMIT_MEMLOCK, &r)) {
perror("setrlimit(RLIMIT_MEMLOCK)");
return EXIT_FAILURE;
}
if (load_bpf_file(bpf_obj_file)) {
printf("ERROR - bpf_log_buf: %s", bpf_log_buf);
return EXIT_FAILURE;
}
if (!prog_fd[0]) {
printf("ERROR - load_bpf_file: %s\n", strerror(errno));
return EXIT_FAILURE;
}
if (debug) {
print_bpf_prog_info();
}
/* Unload/stop tracepoint event by closing fd's */
if (errors_only) {
/* The prog_fd[i] and event_fd[i] depend on the
* order the functions was defined in _kern.c
*/
close(event_fd[2]); /* tracepoint/xdp/xdp_redirect */
close(prog_fd[2]); /* func: trace_xdp_redirect */
close(event_fd[3]); /* tracepoint/xdp/xdp_redirect_map */
close(prog_fd[3]); /* func: trace_xdp_redirect_map */
}
stats_poll(interval, errors_only);
return ret;
}