// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2023 Isovalent */
#include <sys/random.h>
#include <argp.h>
#include "bench.h"
#include "bpf_hashmap_lookup.skel.h"
#include "bpf_util.h"
/* BPF triggering benchmarks */
static struct ctx {
struct bpf_hashmap_lookup *skel;
} ctx;
/* only available to kernel, so define it here */
#define BPF_MAX_LOOPS (1<<23)
#define MAX_KEY_SIZE 1024 /* the size of the key map */
static struct {
__u32 key_size;
__u32 map_flags;
__u32 max_entries;
__u32 nr_entries;
__u32 nr_loops;
} args = {
.key_size = 4,
.map_flags = 0,
.max_entries = 1000,
.nr_entries = 500,
.nr_loops = 1000000,
};
enum {
ARG_KEY_SIZE = 8001,
ARG_MAP_FLAGS,
ARG_MAX_ENTRIES,
ARG_NR_ENTRIES,
ARG_NR_LOOPS,
};
static const struct argp_option opts[] = {
{ "key_size", ARG_KEY_SIZE, "KEY_SIZE", 0,
"The hashmap key size (max 1024)"},
{ "map_flags", ARG_MAP_FLAGS, "MAP_FLAGS", 0,
"The hashmap flags passed to BPF_MAP_CREATE"},
{ "max_entries", ARG_MAX_ENTRIES, "MAX_ENTRIES", 0,
"The hashmap max entries"},
{ "nr_entries", ARG_NR_ENTRIES, "NR_ENTRIES", 0,
"The number of entries to insert/lookup"},
{ "nr_loops", ARG_NR_LOOPS, "NR_LOOPS", 0,
"The number of loops for the benchmark"},
{},
};
static error_t parse_arg(int key, char *arg, struct argp_state *state)
{
long ret;
switch (key) {
case ARG_KEY_SIZE:
ret = strtol(arg, NULL, 10);
if (ret < 1 || ret > MAX_KEY_SIZE) {
fprintf(stderr, "invalid key_size");
argp_usage(state);
}
args.key_size = ret;
break;
case ARG_MAP_FLAGS:
ret = strtol(arg, NULL, 0);
if (ret < 0 || ret > UINT_MAX) {
fprintf(stderr, "invalid map_flags");
argp_usage(state);
}
args.map_flags = ret;
break;
case ARG_MAX_ENTRIES:
ret = strtol(arg, NULL, 10);
if (ret < 1 || ret > UINT_MAX) {
fprintf(stderr, "invalid max_entries");
argp_usage(state);
}
args.max_entries = ret;
break;
case ARG_NR_ENTRIES:
ret = strtol(arg, NULL, 10);
if (ret < 1 || ret > UINT_MAX) {
fprintf(stderr, "invalid nr_entries");
argp_usage(state);
}
args.nr_entries = ret;
break;
case ARG_NR_LOOPS:
ret = strtol(arg, NULL, 10);
if (ret < 1 || ret > BPF_MAX_LOOPS) {
fprintf(stderr, "invalid nr_loops: %ld (min=1 max=%u)\n",
ret, BPF_MAX_LOOPS);
argp_usage(state);
}
args.nr_loops = ret;
break;
default:
return ARGP_ERR_UNKNOWN;
}
return 0;
}
const struct argp bench_hashmap_lookup_argp = {
.options = opts,
.parser = parse_arg,
};
static void validate(void)
{
if (env.consumer_cnt != 0) {
fprintf(stderr, "benchmark doesn't support consumer!\n");
exit(1);
}
if (args.nr_entries > args.max_entries) {
fprintf(stderr, "args.nr_entries is too big! (max %u, got %u)\n",
args.max_entries, args.nr_entries);
exit(1);
}
}
static void *producer(void *input)
{
while (true) {
/* trigger the bpf program */
syscall(__NR_getpgid);
}
return NULL;
}
static void measure(struct bench_res *res)
{
}
static inline void patch_key(u32 i, u32 *key)
{
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
*key = i + 1;
#else
*key = __builtin_bswap32(i + 1);
#endif
/* the rest of key is random */
}
static void setup(void)
{
struct bpf_link *link;
int map_fd;
int ret;
int i;
setup_libbpf();
ctx.skel = bpf_hashmap_lookup__open();
if (!ctx.skel) {
fprintf(stderr, "failed to open skeleton\n");
exit(1);
}
bpf_map__set_max_entries(ctx.skel->maps.hash_map_bench, args.max_entries);
bpf_map__set_key_size(ctx.skel->maps.hash_map_bench, args.key_size);
bpf_map__set_value_size(ctx.skel->maps.hash_map_bench, 8);
bpf_map__set_map_flags(ctx.skel->maps.hash_map_bench, args.map_flags);
ctx.skel->bss->nr_entries = args.nr_entries;
ctx.skel->bss->nr_loops = args.nr_loops / args.nr_entries;
if (args.key_size > 4) {
for (i = 1; i < args.key_size/4; i++)
ctx.skel->bss->key[i] = 2654435761 * i;
}
ret = bpf_hashmap_lookup__load(ctx.skel);
if (ret) {
bpf_hashmap_lookup__destroy(ctx.skel);
fprintf(stderr, "failed to load map: %s", strerror(-ret));
exit(1);
}
/* fill in the hash_map */
map_fd = bpf_map__fd(ctx.skel->maps.hash_map_bench);
for (u64 i = 0; i < args.nr_entries; i++) {
patch_key(i, ctx.skel->bss->key);
bpf_map_update_elem(map_fd, ctx.skel->bss->key, &i, BPF_ANY);
}
link = bpf_program__attach(ctx.skel->progs.benchmark);
if (!link) {
fprintf(stderr, "failed to attach program!\n");
exit(1);
}
}
static inline double events_from_time(u64 time)
{
if (time)
return args.nr_loops * 1000000000llu / time / 1000000.0L;
return 0;
}
static int compute_events(u64 *times, double *events_mean, double *events_stddev, u64 *mean_time)
{
int i, n = 0;
*events_mean = 0;
*events_stddev = 0;
*mean_time = 0;
for (i = 0; i < 32; i++) {
if (!times[i])
break;
*mean_time += times[i];
*events_mean += events_from_time(times[i]);
n += 1;
}
if (!n)
return 0;
*mean_time /= n;
*events_mean /= n;
if (n > 1) {
for (i = 0; i < n; i++) {
double events_i = *events_mean - events_from_time(times[i]);
*events_stddev += events_i * events_i / (n - 1);
}
*events_stddev = sqrt(*events_stddev);
}
return n;
}
static void hashmap_report_final(struct bench_res res[], int res_cnt)
{
unsigned int nr_cpus = bpf_num_possible_cpus();
double events_mean, events_stddev;
u64 mean_time;
int i, n;
for (i = 0; i < nr_cpus; i++) {
n = compute_events(ctx.skel->bss->percpu_times[i], &events_mean,
&events_stddev, &mean_time);
if (n == 0)
continue;
if (env.quiet) {
/* we expect only one cpu to be present */
if (env.affinity)
printf("%.3lf\n", events_mean);
else
printf("cpu%02d %.3lf\n", i, events_mean);
} else {
printf("cpu%02d: lookup %.3lfM ± %.3lfM events/sec"
" (approximated from %d samples of ~%lums)\n",
i, events_mean, 2*events_stddev,
n, mean_time / 1000000);
}
}
}
const struct bench bench_bpf_hashmap_lookup = {
.name = "bpf-hashmap-lookup",
.argp = &bench_hashmap_lookup_argp,
.validate = validate,
.setup = setup,
.producer_thread = producer,
.measure = measure,
.report_progress = NULL,
.report_final = hashmap_report_final,
};
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