linux/samples/bpf/xdp_monitor_user.c
Jesper Dangaard Brouer c4eb7f4643 samples/bpf: xdp_monitor increase memory rlimit
Other concurrent running programs, like perf or the XDP program what
needed to be monitored, might take up part of the max locked memory
limit.  Thus, the xdp_monitor tool have to set the RLIMIT_MEMLOCK to
RLIM_INFINITY, as it cannot determine a more sane limit.

Using the man exit(3) specified EXIT_FAILURE return exit code, and
correct other users too.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-06 10:04:36 -07:00

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;
}