linux/samples/bpf/map_perf_test_user.c
David Herrmann b8a943e294 samples/bpf: add lpm-trie benchmark
Extend the map_perf_test_{user,kern}.c infrastructure to stress test
lpm-trie lookups. We hook into the kprobe on sys_gettid() and measure
the latency depending on trie size and lookup count.

On my Intel Haswell i7-6400U, a single gettid() syscall with an empty
bpf program takes roughly 6.5us on my system. Lookups in empty tries
take ~1.8us on first try, ~0.9us on retries. Lookups in tries with 8192
entries take ~7.1us (on the first _and_ any subsequent try).

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-23 16:10:38 -05:00

238 lines
5.0 KiB
C

/* Copyright (c) 2016 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#define _GNU_SOURCE
#include <sched.h>
#include <stdio.h>
#include <sys/types.h>
#include <asm/unistd.h>
#include <unistd.h>
#include <assert.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <signal.h>
#include <linux/bpf.h>
#include <string.h>
#include <time.h>
#include <sys/resource.h>
#include "libbpf.h"
#include "bpf_load.h"
#define MAX_CNT 1000000
static __u64 time_get_ns(void)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000000000ull + ts.tv_nsec;
}
#define HASH_PREALLOC (1 << 0)
#define PERCPU_HASH_PREALLOC (1 << 1)
#define HASH_KMALLOC (1 << 2)
#define PERCPU_HASH_KMALLOC (1 << 3)
#define LRU_HASH_PREALLOC (1 << 4)
#define PERCPU_LRU_HASH_PREALLOC (1 << 5)
#define LPM_KMALLOC (1 << 6)
static int test_flags = ~0;
static void test_hash_prealloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_getuid);
printf("%d:hash_map_perf pre-alloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void test_lru_hash_prealloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_getpid);
printf("%d:lru_hash_map_perf pre-alloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void test_percpu_lru_hash_prealloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_getppid);
printf("%d:lru_hash_map_perf pre-alloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void test_percpu_hash_prealloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_geteuid);
printf("%d:percpu_hash_map_perf pre-alloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void test_hash_kmalloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_getgid);
printf("%d:hash_map_perf kmalloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void test_percpu_hash_kmalloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_getegid);
printf("%d:percpu_hash_map_perf kmalloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void test_lpm_kmalloc(int cpu)
{
__u64 start_time;
int i;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++)
syscall(__NR_gettid);
printf("%d:lpm_perf kmalloc %lld events per sec\n",
cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
}
static void loop(int cpu)
{
cpu_set_t cpuset;
CPU_ZERO(&cpuset);
CPU_SET(cpu, &cpuset);
sched_setaffinity(0, sizeof(cpuset), &cpuset);
if (test_flags & HASH_PREALLOC)
test_hash_prealloc(cpu);
if (test_flags & PERCPU_HASH_PREALLOC)
test_percpu_hash_prealloc(cpu);
if (test_flags & HASH_KMALLOC)
test_hash_kmalloc(cpu);
if (test_flags & PERCPU_HASH_KMALLOC)
test_percpu_hash_kmalloc(cpu);
if (test_flags & LRU_HASH_PREALLOC)
test_lru_hash_prealloc(cpu);
if (test_flags & PERCPU_LRU_HASH_PREALLOC)
test_percpu_lru_hash_prealloc(cpu);
if (test_flags & LPM_KMALLOC)
test_lpm_kmalloc(cpu);
}
static void run_perf_test(int tasks)
{
pid_t pid[tasks];
int i;
for (i = 0; i < tasks; i++) {
pid[i] = fork();
if (pid[i] == 0) {
loop(i);
exit(0);
} else if (pid[i] == -1) {
printf("couldn't spawn #%d process\n", i);
exit(1);
}
}
for (i = 0; i < tasks; i++) {
int status;
assert(waitpid(pid[i], &status, 0) == pid[i]);
assert(status == 0);
}
}
static void fill_lpm_trie(void)
{
struct bpf_lpm_trie_key *key;
unsigned long value = 0;
unsigned int i;
int r;
key = alloca(sizeof(*key) + 4);
key->prefixlen = 32;
for (i = 0; i < 512; ++i) {
key->prefixlen = rand() % 33;
key->data[0] = rand() & 0xff;
key->data[1] = rand() & 0xff;
key->data[2] = rand() & 0xff;
key->data[3] = rand() & 0xff;
r = bpf_map_update_elem(map_fd[6], key, &value, 0);
assert(!r);
}
key->prefixlen = 32;
key->data[0] = 192;
key->data[1] = 168;
key->data[2] = 0;
key->data[3] = 1;
value = 128;
r = bpf_map_update_elem(map_fd[6], key, &value, 0);
assert(!r);
}
int main(int argc, char **argv)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
char filename[256];
int num_cpu = 8;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
setrlimit(RLIMIT_MEMLOCK, &r);
if (argc > 1)
test_flags = atoi(argv[1]) ? : test_flags;
if (argc > 2)
num_cpu = atoi(argv[2]) ? : num_cpu;
if (load_bpf_file(filename)) {
printf("%s", bpf_log_buf);
return 1;
}
fill_lpm_trie();
run_perf_test(num_cpu);
return 0;
}