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authorMartin KaFai Lau <kafai@fb.com>2017-04-14 10:30:28 -0700
committerDavid S. Miller <davem@davemloft.net>2017-04-17 13:55:52 -0400
commit9fd63d05f3e8476282cd8c484eb34d3f6be54f40 (patch)
treef3fb9ca5e7f8e8be6114a29ee23b17357522000d /samples/bpf
parentbf8db5d243a103ccd3f6d82a110e2302608e248c (diff)
bpf: Allow bpf sample programs (*_user.c) to change bpf_map_def
The current bpf_map_def is statically defined during compile time. This patch allows the *_user.c program to change it during runtime. It is done by adding load_bpf_file_fixup_map() which takes a callback. The callback will be called before creating each map so that it has a chance to modify the bpf_map_def. The current usecase is to change max_entries in map_perf_test. It is interesting to test with a much bigger map size in some cases (e.g. the following patch on bpf_lru_map.c). However, it is hard to find one size to fit all testing environment. Hence, it is handy to take the max_entries as a cmdline arg and then configure the bpf_map_def during runtime. This patch adds two cmdline args. One is to configure the map's max_entries. Another is to configure the max_cnt which controls how many times a syscall is called. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'samples/bpf')
-rw-r--r--samples/bpf/bpf_load.c114
-rw-r--r--samples/bpf/bpf_load.h13
-rw-r--r--samples/bpf/map_perf_test_user.c148
3 files changed, 201 insertions, 74 deletions
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index dcdce1270d38..0d449d8032d1 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -21,6 +21,7 @@
#include <sys/mman.h>
#include <poll.h>
#include <ctype.h>
+#include <assert.h>
#include "libbpf.h"
#include "bpf_load.h"
#include "perf-sys.h"
@@ -37,15 +38,6 @@ int event_fd[MAX_PROGS];
int prog_cnt;
int prog_array_fd = -1;
-struct bpf_map_def {
- unsigned int type;
- unsigned int key_size;
- unsigned int value_size;
- unsigned int max_entries;
- unsigned int map_flags;
- unsigned int inner_map_idx;
-};
-
static int populate_prog_array(const char *event, int prog_fd)
{
int ind = atoi(event), err;
@@ -193,11 +185,14 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
return 0;
}
-static int load_maps(struct bpf_map_def *maps, int len)
+static int load_maps(struct bpf_map_def *maps, int len,
+ const char **map_names, fixup_map_cb fixup_map)
{
int i;
for (i = 0; i < len / sizeof(struct bpf_map_def); i++) {
+ if (fixup_map)
+ fixup_map(&maps[i], map_names[i], i);
if (maps[i].type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
maps[i].type == BPF_MAP_TYPE_HASH_OF_MAPS) {
@@ -280,14 +275,64 @@ static int parse_relo_and_apply(Elf_Data *data, Elf_Data *symbols,
return 0;
}
-int load_bpf_file(char *path)
+static int cmp_symbols(const void *l, const void *r)
+{
+ const GElf_Sym *lsym = (const GElf_Sym *)l;
+ const GElf_Sym *rsym = (const GElf_Sym *)r;
+
+ if (lsym->st_value < rsym->st_value)
+ return -1;
+ else if (lsym->st_value > rsym->st_value)
+ return 1;
+ else
+ return 0;
+}
+
+static int get_sorted_map_names(Elf *elf, Elf_Data *symbols, int maps_shndx,
+ int strtabidx, char **map_names)
+{
+ GElf_Sym map_symbols[MAX_MAPS];
+ int i, nr_maps = 0;
+
+ for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) {
+ assert(nr_maps < MAX_MAPS);
+ if (!gelf_getsym(symbols, i, &map_symbols[nr_maps]))
+ continue;
+ if (map_symbols[nr_maps].st_shndx != maps_shndx)
+ continue;
+ nr_maps++;
+ }
+
+ qsort(map_symbols, nr_maps, sizeof(GElf_Sym), cmp_symbols);
+
+ for (i = 0; i < nr_maps; i++) {
+ char *map_name;
+
+ map_name = elf_strptr(elf, strtabidx, map_symbols[i].st_name);
+ if (!map_name) {
+ printf("cannot get map symbol\n");
+ return 1;
+ }
+
+ map_names[i] = strdup(map_name);
+ if (!map_names[i]) {
+ printf("strdup(%s): %s(%d)\n", map_name,
+ strerror(errno), errno);
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map)
{
- int fd, i;
+ int fd, i, ret, maps_shndx = -1, strtabidx = -1;
Elf *elf;
GElf_Ehdr ehdr;
GElf_Shdr shdr, shdr_prog;
- Elf_Data *data, *data_prog, *symbols = NULL;
- char *shname, *shname_prog;
+ Elf_Data *data, *data_prog, *data_maps = NULL, *symbols = NULL;
+ char *shname, *shname_prog, *map_names[MAX_MAPS] = { NULL };
/* reset global variables */
kern_version = 0;
@@ -335,14 +380,33 @@ int load_bpf_file(char *path)
}
memcpy(&kern_version, data->d_buf, sizeof(int));
} else if (strcmp(shname, "maps") == 0) {
- processed_sec[i] = true;
- if (load_maps(data->d_buf, data->d_size))
- return 1;
+ maps_shndx = i;
+ data_maps = data;
} else if (shdr.sh_type == SHT_SYMTAB) {
+ strtabidx = shdr.sh_link;
symbols = data;
}
}
+ ret = 1;
+
+ if (!symbols) {
+ printf("missing SHT_SYMTAB section\n");
+ goto done;
+ }
+
+ if (data_maps) {
+ if (get_sorted_map_names(elf, symbols, maps_shndx, strtabidx,
+ map_names))
+ goto done;
+
+ if (load_maps(data_maps->d_buf, data_maps->d_size,
+ (const char **)map_names, fixup_map))
+ goto done;
+
+ processed_sec[maps_shndx] = true;
+ }
+
/* load programs that need map fixup (relocations) */
for (i = 1; i < ehdr.e_shnum; i++) {
if (processed_sec[i])
@@ -399,8 +463,22 @@ int load_bpf_file(char *path)
load_and_attach(shname, data->d_buf, data->d_size);
}
+ ret = 0;
+done:
+ for (i = 0; i < MAX_MAPS; i++)
+ free(map_names[i]);
close(fd);
- return 0;
+ return ret;
+}
+
+int load_bpf_file(char *path)
+{
+ return do_load_bpf_file(path, NULL);
+}
+
+int load_bpf_file_fixup_map(const char *path, fixup_map_cb fixup_map)
+{
+ return do_load_bpf_file(path, fixup_map);
}
void read_trace_pipe(void)
diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
index c827827299b3..68f6b2d22507 100644
--- a/samples/bpf/bpf_load.h
+++ b/samples/bpf/bpf_load.h
@@ -6,6 +6,18 @@
#define MAX_MAPS 32
#define MAX_PROGS 32
+struct bpf_map_def {
+ unsigned int type;
+ unsigned int key_size;
+ unsigned int value_size;
+ unsigned int max_entries;
+ unsigned int map_flags;
+ unsigned int inner_map_idx;
+};
+
+typedef void (*fixup_map_cb)(struct bpf_map_def *map, const char *map_name,
+ int idx);
+
extern int map_fd[MAX_MAPS];
extern int prog_fd[MAX_PROGS];
extern int event_fd[MAX_PROGS];
@@ -25,6 +37,7 @@ extern int prog_cnt;
* returns zero on success
*/
int load_bpf_file(char *path);
+int load_bpf_file_fixup_map(const char *path, fixup_map_cb fixup_map);
void read_trace_pipe(void);
struct ksym {
diff --git a/samples/bpf/map_perf_test_user.c b/samples/bpf/map_perf_test_user.c
index 51cb8f238aa2..2a12f48b5c6d 100644
--- a/samples/bpf/map_perf_test_user.c
+++ b/samples/bpf/map_perf_test_user.c
@@ -24,7 +24,7 @@
#include "libbpf.h"
#include "bpf_load.h"
-#define MAX_CNT 1000000
+#define TEST_BIT(t) (1U << (t))
static __u64 time_get_ns(void)
{
@@ -34,17 +34,39 @@ static __u64 time_get_ns(void)
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 NOCOMMON_LRU_HASH_PREALLOC (1 << 5)
-#define LPM_KMALLOC (1 << 6)
-#define HASH_LOOKUP (1 << 7)
-#define ARRAY_LOOKUP (1 << 8)
+enum test_type {
+ HASH_PREALLOC,
+ PERCPU_HASH_PREALLOC,
+ HASH_KMALLOC,
+ PERCPU_HASH_KMALLOC,
+ LRU_HASH_PREALLOC,
+ NOCOMMON_LRU_HASH_PREALLOC,
+ LPM_KMALLOC,
+ HASH_LOOKUP,
+ ARRAY_LOOKUP,
+ NR_TESTS,
+};
+
+const char *test_map_names[NR_TESTS] = {
+ [HASH_PREALLOC] = "hash_map",
+ [PERCPU_HASH_PREALLOC] = "percpu_hash_map",
+ [HASH_KMALLOC] = "hash_map_alloc",
+ [PERCPU_HASH_KMALLOC] = "percpu_hash_map_alloc",
+ [LRU_HASH_PREALLOC] = "lru_hash_map",
+ [NOCOMMON_LRU_HASH_PREALLOC] = "nocommon_lru_hash_map",
+ [LPM_KMALLOC] = "lpm_trie_map_alloc",
+ [HASH_LOOKUP] = "hash_map",
+ [ARRAY_LOOKUP] = "array_map",
+};
static int test_flags = ~0;
+static uint32_t num_map_entries;
+static uint32_t max_cnt = 1000000;
+
+static int check_test_flags(enum test_type t)
+{
+ return test_flags & TEST_BIT(t);
+}
static void test_hash_prealloc(int cpu)
{
@@ -52,13 +74,13 @@ static void test_hash_prealloc(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ 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));
+ cpu, max_cnt * 1000000000ll / (time_get_ns() - start_time));
}
-static void do_test_lru(int lru_test_flag, int cpu)
+static void do_test_lru(enum test_type test, int cpu)
{
struct sockaddr_in6 in6 = { .sin6_family = AF_INET6 };
const char *test_name;
@@ -68,10 +90,10 @@ static void do_test_lru(int lru_test_flag, int cpu)
in6.sin6_addr.s6_addr16[0] = 0xdead;
in6.sin6_addr.s6_addr16[1] = 0xbeef;
- if (lru_test_flag & LRU_HASH_PREALLOC) {
+ if (test == LRU_HASH_PREALLOC) {
test_name = "lru_hash_map_perf";
in6.sin6_addr.s6_addr16[7] = 0;
- } else if (lru_test_flag & NOCOMMON_LRU_HASH_PREALLOC) {
+ } else if (test == NOCOMMON_LRU_HASH_PREALLOC) {
test_name = "nocommon_lru_hash_map_perf";
in6.sin6_addr.s6_addr16[7] = 1;
} else {
@@ -79,13 +101,13 @@ static void do_test_lru(int lru_test_flag, int cpu)
}
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++) {
+ for (i = 0; i < max_cnt; i++) {
ret = connect(-1, (const struct sockaddr *)&in6, sizeof(in6));
assert(ret == -1 && errno == EBADF);
}
printf("%d:%s pre-alloc %lld events per sec\n",
cpu, test_name,
- MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
+ max_cnt * 1000000000ll / (time_get_ns() - start_time));
}
static void test_lru_hash_prealloc(int cpu)
@@ -104,10 +126,10 @@ static void test_percpu_hash_prealloc(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ 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));
+ cpu, max_cnt * 1000000000ll / (time_get_ns() - start_time));
}
static void test_hash_kmalloc(int cpu)
@@ -116,10 +138,10 @@ static void test_hash_kmalloc(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ 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));
+ cpu, max_cnt * 1000000000ll / (time_get_ns() - start_time));
}
static void test_percpu_hash_kmalloc(int cpu)
@@ -128,10 +150,10 @@ static void test_percpu_hash_kmalloc(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ 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));
+ cpu, max_cnt * 1000000000ll / (time_get_ns() - start_time));
}
static void test_lpm_kmalloc(int cpu)
@@ -140,10 +162,10 @@ static void test_lpm_kmalloc(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ 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));
+ cpu, max_cnt * 1000000000ll / (time_get_ns() - start_time));
}
static void test_hash_lookup(int cpu)
@@ -152,10 +174,10 @@ static void test_hash_lookup(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ for (i = 0; i < max_cnt; i++)
syscall(__NR_getpgid, 0);
printf("%d:hash_lookup %lld lookups per sec\n",
- cpu, MAX_CNT * 1000000000ll * 64 / (time_get_ns() - start_time));
+ cpu, max_cnt * 1000000000ll * 64 / (time_get_ns() - start_time));
}
static void test_array_lookup(int cpu)
@@ -164,46 +186,38 @@ static void test_array_lookup(int cpu)
int i;
start_time = time_get_ns();
- for (i = 0; i < MAX_CNT; i++)
+ for (i = 0; i < max_cnt; i++)
syscall(__NR_getpgrp, 0);
printf("%d:array_lookup %lld lookups per sec\n",
- cpu, MAX_CNT * 1000000000ll * 64 / (time_get_ns() - start_time));
+ cpu, max_cnt * 1000000000ll * 64 / (time_get_ns() - start_time));
}
+typedef void (*test_func)(int cpu);
+const test_func test_funcs[] = {
+ [HASH_PREALLOC] = test_hash_prealloc,
+ [PERCPU_HASH_PREALLOC] = test_percpu_hash_prealloc,
+ [HASH_KMALLOC] = test_hash_kmalloc,
+ [PERCPU_HASH_KMALLOC] = test_percpu_hash_kmalloc,
+ [LRU_HASH_PREALLOC] = test_lru_hash_prealloc,
+ [NOCOMMON_LRU_HASH_PREALLOC] = test_nocommon_lru_hash_prealloc,
+ [LPM_KMALLOC] = test_lpm_kmalloc,
+ [HASH_LOOKUP] = test_hash_lookup,
+ [ARRAY_LOOKUP] = test_array_lookup,
+};
+
static void loop(int cpu)
{
cpu_set_t cpuset;
+ int i;
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 & NOCOMMON_LRU_HASH_PREALLOC)
- test_nocommon_lru_hash_prealloc(cpu);
-
- if (test_flags & LPM_KMALLOC)
- test_lpm_kmalloc(cpu);
-
- if (test_flags & HASH_LOOKUP)
- test_hash_lookup(cpu);
-
- if (test_flags & ARRAY_LOOKUP)
- test_array_lookup(cpu);
+ for (i = 0; i < NR_TESTS; i++) {
+ if (check_test_flags(i))
+ test_funcs[i](cpu);
+ }
}
static void run_perf_test(int tasks)
@@ -260,6 +274,22 @@ static void fill_lpm_trie(void)
assert(!r);
}
+static void fixup_map(struct bpf_map_def *map, const char *name, int idx)
+{
+ int i;
+
+ if (num_map_entries <= 0)
+ return;
+
+ /* Only change the max_entries for the enabled test(s) */
+ for (i = 0; i < NR_TESTS; i++) {
+ if (!strcmp(test_map_names[i], name) &&
+ (check_test_flags(i))) {
+ map->max_entries = num_map_entries;
+ }
+ }
+}
+
int main(int argc, char **argv)
{
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
@@ -275,7 +305,13 @@ int main(int argc, char **argv)
if (argc > 2)
num_cpu = atoi(argv[2]) ? : num_cpu;
- if (load_bpf_file(filename)) {
+ if (argc > 3)
+ num_map_entries = atoi(argv[3]);
+
+ if (argc > 4)
+ max_cnt = atoi(argv[4]);
+
+ if (load_bpf_file_fixup_map(filename, fixup_map)) {
printf("%s", bpf_log_buf);
return 1;
}