Re: [PATCH bpf-next v3 7/7] selftests/bpf: add test cases for queue and stack maps

Mauricio Vasquez
2018-10-19T01:35:47Z

On 10/18/18 11:36 AM, Song Liu wrote:
> On Thu, Oct 18, 2018 at 6:16 AM Mauricio Vasquez B
> <mauricio.vasquez@polito.it> wrote:
>> test_maps:
>> Tests that queue/stack maps are behaving correctly even in corner cases
>>
>> test_progs:
>> Tests new ebpf helpers
>>
>> Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
>> ---
>> tools/lib/bpf/bpf.c | 12 ++
>> tools/lib/bpf/bpf.h | 2
>> tools/testing/selftests/bpf/Makefile | 5 +
>> tools/testing/selftests/bpf/bpf_helpers.h | 7 +
>> tools/testing/selftests/bpf/test_maps.c | 122 ++++++++++++++++++++
>> tools/testing/selftests/bpf/test_progs.c | 99 ++++++++++++++++
>> tools/testing/selftests/bpf/test_queue_map.c | 4 +
>> tools/testing/selftests/bpf/test_queue_stack_map.h | 59 ++++++++++
>> tools/testing/selftests/bpf/test_stack_map.c | 4 +
>> 9 files changed, 313 insertions(+), 1 deletion(-)
>> create mode 100644 tools/testing/selftests/bpf/test_queue_map.c
>> create mode 100644 tools/testing/selftests/bpf/test_queue_stack_map.h
>> create mode 100644 tools/testing/selftests/bpf/test_stack_map.c
>>
>> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
>> index d70a255cb05e..03f9bcc4ef50 100644
>> --- a/tools/lib/bpf/bpf.c
>> +++ b/tools/lib/bpf/bpf.c
>> @@ -278,6 +278,18 @@ int bpf_map_lookup_elem(int fd, const void *key, void *value)
>> return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
>> }
>>
>> +int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
>> +{
>> + union bpf_attr attr;
>> +
>> + bzero(&attr, sizeof(attr));
>> + attr.map_fd = fd;
>> + attr.key = ptr_to_u64(key);
>> + attr.value = ptr_to_u64(value);
>> +
>> + return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
>> +}
>> +
>> int bpf_map_delete_elem(int fd, const void *key)
>> {
>> union bpf_attr attr;
>> diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
>> index 258c3c178333..26a51538213c 100644
>> --- a/tools/lib/bpf/bpf.h
>> +++ b/tools/lib/bpf/bpf.h
>> @@ -99,6 +99,8 @@ LIBBPF_API int bpf_map_update_elem(int fd, const void *key, const void *value,
>> __u64 flags);
>>
>> LIBBPF_API int bpf_map_lookup_elem(int fd, const void *key, void *value);
>> +LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd, const void *key,
>> + void *value);
>> LIBBPF_API int bpf_map_delete_elem(int fd, const void *key);
>> LIBBPF_API int bpf_map_get_next_key(int fd, const void *key, void *next_key);
>> LIBBPF_API int bpf_obj_pin(int fd, const char *pathname);
>> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
>> index d99dd6fc3fbe..e39dfb4e7970 100644
>> --- a/tools/testing/selftests/bpf/Makefile
>> +++ b/tools/testing/selftests/bpf/Makefile
>> @@ -37,7 +37,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
>> test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
>> get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o \
>> test_skb_cgroup_id_kern.o bpf_flow.o netcnt_prog.o \
>> - test_sk_lookup_kern.o test_xdp_vlan.o
>> + test_sk_lookup_kern.o test_xdp_vlan.o test_queue_map.o test_stack_map.o
>>
>> # Order correspond to 'make run_tests' order
>> TEST_PROGS := test_kmod.sh \
>> @@ -118,6 +118,9 @@ CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi \
>> $(OUTPUT)/test_l4lb_noinline.o: CLANG_FLAGS += -fno-inline
>> $(OUTPUT)/test_xdp_noinline.o: CLANG_FLAGS += -fno-inline
>>
>> +$(OUTPUT)/test_queue_map.o: test_queue_stack_map.h
>> +$(OUTPUT)/test_stack_map.o: test_queue_stack_map.h
> This looks weird. You meant the .c files, right?

Queue and stack tests are very similar, in order to avoid a lot of code
duplication I created a single test_queue_stack_map.h file where all the
logic is placed.

There are two .c files (test_queue_map.c and test_stack_map.c) they
define the map type and include test_queue_stack_map.h.

test_queue_map.o and test_stack_map.o create an implicit dependency on
test_queue_map.c and test_stack_map.c, but the dependency on the header
is also needed, so I added those two lines.

>
>> +
>> BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
>> BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
>> BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
>> diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
>> index fda8c162d0df..6407a3df0f3b 100644
>> --- a/tools/testing/selftests/bpf/bpf_helpers.h
>> +++ b/tools/testing/selftests/bpf/bpf_helpers.h
>> @@ -16,6 +16,13 @@ static int (*bpf_map_update_elem)(void *map, void *key, void *value,
>> (void *) BPF_FUNC_map_update_elem;
>> static int (*bpf_map_delete_elem)(void *map, void *key) =
>> (void *) BPF_FUNC_map_delete_elem;
>> +static int (*bpf_map_push_elem)(void *map, void *value,
>> + unsigned long long flags) =
>> + (void *) BPF_FUNC_map_push_elem;
>> +static int (*bpf_map_pop_elem)(void *map, void *value) =
>> + (void *) BPF_FUNC_map_pop_elem;
>> +static int (*bpf_map_peek_elem)(void *map, void *value) =
>> + (void *) BPF_FUNC_map_peek_elem;
>> static int (*bpf_probe_read)(void *dst, int size, void *unsafe_ptr) =
>> (void *) BPF_FUNC_probe_read;
>> static unsigned long long (*bpf_ktime_get_ns)(void) =
>> diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
>> index 9b552c0fc47d..4db2116e52be 100644
>> --- a/tools/testing/selftests/bpf/test_maps.c
>> +++ b/tools/testing/selftests/bpf/test_maps.c
>> @@ -15,6 +15,7 @@
>> #include <string.h>
>> #include <assert.h>
>> #include <stdlib.h>
>> +#include <time.h>
>>
>> #include <sys/wait.h>
>> #include <sys/socket.h>
>> @@ -471,6 +472,122 @@ static void test_devmap(int task, void *data)
>> close(fd);
>> }
>>
>> +static void test_queuemap(int task, void *data)
>> +{
>> + const int MAP_SIZE = 32;
>> + __u32 vals[MAP_SIZE + MAP_SIZE/2], val;
>> + int fd, i;
>> +
>> + /* Fill test values to be used */
>> + for (i = 0; i < MAP_SIZE + MAP_SIZE/2; i++)
>> + vals[i] = rand();
>> +
>> + /* Invalid key size */
>> + fd = bpf_create_map(BPF_MAP_TYPE_QUEUE, 4, sizeof(val), MAP_SIZE,
>> + map_flags);
>> + assert(fd < 0 && errno == EINVAL);
>> +
>> + fd = bpf_create_map(BPF_MAP_TYPE_QUEUE, 0, sizeof(val), MAP_SIZE,
>> + map_flags);
>> + /* Queue map does not support BPF_F_NO_PREALLOC */
>> + if (map_flags & BPF_F_NO_PREALLOC) {
>> + assert(fd < 0 && errno == EINVAL);
>> + return;
>> + }
>> + if (fd < 0) {
>> + printf("Failed to create queuemap '%s'!\n", strerror(errno));
>> + exit(1);
>> + }
>> +
>> + /* Push MAP_SIZE elements */
>> + for (i = 0; i < MAP_SIZE; i++)
>> + assert(bpf_map_update_elem(fd, NULL, &vals[i], 0) == 0);
>> +
>> + /* Check that element cannot be pushed due to max_entries limit */
>> + assert(bpf_map_update_elem(fd, NULL, &val, 0) == -1 &&
>> + errno == E2BIG);
>> +
>> + /* Peek element */
>> + assert(bpf_map_lookup_elem(fd, NULL, &val) == 0 && val == vals[0]);
>> +
>> + /* Replace half elements */
>> + for (i = MAP_SIZE; i < MAP_SIZE + MAP_SIZE/2; i++)
>> + assert(bpf_map_update_elem(fd, NULL, &vals[i], BPF_EXIST) == 0);
>> +
>> + /* Pop all elements */
>> + for (i = MAP_SIZE/2; i < MAP_SIZE + MAP_SIZE/2; i++)
>> + assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == 0 &&
>> + val == vals[i]);
>> +
>> + /* Check that there are not elements left */
>> + assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == -1 &&
>> + errno == ENOENT);
>> +
>> + /* Check that non supported functions set errno to EINVAL */
>> + assert(bpf_map_delete_elem(fd, NULL) == -1 && errno == EINVAL);
>> + assert(bpf_map_get_next_key(fd, NULL, NULL) == -1 && errno == EINVAL);
>> +
>> + close(fd);
>> +}
>> +
>> +static void test_stackmap(int task, void *data)
>> +{
>> + const int MAP_SIZE = 32;
>> + __u32 vals[MAP_SIZE + MAP_SIZE/2], val;
>> + int fd, i;
>> +
>> + /* Fill test values to be used */
>> + for (i = 0; i < MAP_SIZE + MAP_SIZE/2; i++)
>> + vals[i] = rand();
>> +
>> + /* Invalid key size */
>> + fd = bpf_create_map(BPF_MAP_TYPE_STACK, 4, sizeof(val), MAP_SIZE,
>> + map_flags);
>> + assert(fd < 0 && errno == EINVAL);
>> +
>> + fd = bpf_create_map(BPF_MAP_TYPE_STACK, 0, sizeof(val), MAP_SIZE,
>> + map_flags);
>> + /* Stack map does not support BPF_F_NO_PREALLOC */
>> + if (map_flags & BPF_F_NO_PREALLOC) {
>> + assert(fd < 0 && errno == EINVAL);
>> + return;
>> + }
>> + if (fd < 0) {
>> + printf("Failed to create stackmap '%s'!\n", strerror(errno));
>> + exit(1);
>> + }
>> +
>> + /* Push MAP_SIZE elements */
>> + for (i = 0; i < MAP_SIZE; i++)
>> + assert(bpf_map_update_elem(fd, NULL, &vals[i], 0) == 0);
>> +
>> + /* Check that element cannot be pushed due to max_entries limit */
>> + assert(bpf_map_update_elem(fd, NULL, &val, 0) == -1 &&
>> + errno == E2BIG);
>> +
>> + /* Peek element */
>> + assert(bpf_map_lookup_elem(fd, NULL, &val) == 0 && val == vals[i - 1]);
>> +
>> + /* Replace half elements */
>> + for (i = MAP_SIZE; i < MAP_SIZE + MAP_SIZE/2; i++)
>> + assert(bpf_map_update_elem(fd, NULL, &vals[i], BPF_EXIST) == 0);
>> +
>> + /* Pop all elements */
>> + for (i = MAP_SIZE + MAP_SIZE/2 - 1; i >= MAP_SIZE/2; i--)
>> + assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == 0 &&
>> + val == vals[i]);
>> +
>> + /* Check that there are not elements left */
>> + assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == -1 &&
>> + errno == ENOENT);
>> +
>> + /* Check that non supported functions set errno to EINVAL */
>> + assert(bpf_map_delete_elem(fd, NULL) == -1 && errno == EINVAL);
>> + assert(bpf_map_get_next_key(fd, NULL, NULL) == -1 && errno == EINVAL);
>> +
>> + close(fd);
>> +}
>> +
>> #include <sys/socket.h>
>> #include <sys/ioctl.h>
>> #include <arpa/inet.h>
>> @@ -1434,10 +1551,15 @@ static void run_all_tests(void)
>> test_map_wronly();
>>
>> test_reuseport_array();
>> +
>> + test_queuemap(0, NULL);
>> + test_stackmap(0, NULL);
>> }
>>
>> int main(void)
>> {
>> + srand(time(NULL));
>> +
>> map_flags = 0;
>> run_all_tests();
>>
>> diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
>> index e8becca9c521..2d3c04f45530 100644
>> --- a/tools/testing/selftests/bpf/test_progs.c
>> +++ b/tools/testing/selftests/bpf/test_progs.c
>> @@ -1735,8 +1735,105 @@ static void test_reference_tracking()
>> bpf_object__close(obj);
>> }
>>
>> +enum {
>> + QUEUE,
>> + STACK,
>> +};
>> +
>> +static void test_queue_stack_map(int type)
>> +{
>> + const int MAP_SIZE = 32;
>> + __u32 vals[MAP_SIZE], duration, retval, size, val;
>> + int i, err, prog_fd, map_in_fd, map_out_fd;
>> + char file[32], buf[128];
>> + struct bpf_object *obj;
>> + struct iphdr *iph = (void *)buf + sizeof(struct ethhdr);
>> +
>> + /* Fill test values to be used */
>> + for (i = 0; i < MAP_SIZE; i++)
>> + vals[i] = rand();
>> +
>> + if (type == QUEUE)
>> + strncpy(file, "./test_queue_map.o", sizeof(file));
>> + else if (type == STACK)
>> + strncpy(file, "./test_stack_map.o", sizeof(file));
>> + else
>> + return;
>> +
>> + err = bpf_prog_load(file, BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd);
>> + if (err) {
>> + error_cnt++;
>> + return;
>> + }
>> +
>> + map_in_fd = bpf_find_map(__func__, obj, "map_in");
>> + if (map_in_fd < 0)
>> + goto out;
>> +
>> + map_out_fd = bpf_find_map(__func__, obj, "map_out");
>> + if (map_out_fd < 0)
>> + goto out;
>> +
>> + /* Push 32 elements to the input map */
>> + for (i = 0; i < MAP_SIZE; i++) {
>> + err = bpf_map_update_elem(map_in_fd, NULL, &vals[i], 0);
>> + if (err) {
>> + error_cnt++;
>> + goto out;
>> + }
>> + }
>> +
>> + /* The eBPF program pushes iph.saddr in the output map,
>> + * pops the input map and saves this value in iph.daddr
>> + */
>> + for (i = 0; i < MAP_SIZE; i++) {
>> + if (type == QUEUE) {
>> + val = vals[i];
>> + pkt_v4.iph.saddr = vals[i] * 5;
>> + } else if (type == STACK) {
>> + val = vals[MAP_SIZE - 1 - i];
>> + pkt_v4.iph.saddr = vals[MAP_SIZE - 1 - i] * 5;
>> + }
>> +
>> + err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
>> + buf, &size, &retval, &duration);
>> + if (err || retval || size != sizeof(pkt_v4) ||
>> + iph->daddr != val)
>> + break;
>> + }
>> +
>> + CHECK(err || retval || size != sizeof(pkt_v4) || iph->daddr != val,
>> + "bpf_map_pop_elem",
>> + "err %d errno %d retval %d size %d iph->daddr %u\n",
>> + err, errno, retval, size, iph->daddr);
>> +
>> + /* Queue is empty, program should return TC_ACT_SHOT */
>> + err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
>> + buf, &size, &retval, &duration);
>> + CHECK(err || retval != 2 /* TC_ACT_SHOT */|| size != sizeof(pkt_v4),
>> + "check-queue-stack-map-empty",
>> + "err %d errno %d retval %d size %d\n",
>> + err, errno, retval, size);
>> +
>> + /* Check that the program pushed elements correctly */
>> + for (i = 0; i < MAP_SIZE; i++) {
>> + err = bpf_map_lookup_and_delete_elem(map_out_fd, NULL, &val);
>> + if (err || val != vals[i] * 5)
>> + break;
>> + }
>> +
>> + CHECK(i != MAP_SIZE && (err || val != vals[i] * 5),
>> + "bpf_map_push_elem", "err %d value %u\n", err, val);
>> +
>> +out:
>> + pkt_v4.iph.saddr = 0;
>> + bpf_object__close(obj);
>> +}
>> +
>> int main(void)
>> {
>> + srand(time(NULL));
>> +
>> jit_enabled = is_jit_enabled();
>>
>> test_pkt_access();
>> @@ -1757,6 +1854,8 @@ int main(void)
>> test_task_fd_query_rawtp();
>> test_task_fd_query_tp();
>> test_reference_tracking();
>> + test_queue_stack_map(QUEUE);
>> + test_queue_stack_map(STACK);
>>
>> printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
>> return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
>> diff --git a/tools/testing/selftests/bpf/test_queue_map.c b/tools/testing/selftests/bpf/test_queue_map.c
>> new file mode 100644
>> index 000000000000..87db1f9da33d
>> --- /dev/null
>> +++ b/tools/testing/selftests/bpf/test_queue_map.c
>> @@ -0,0 +1,4 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +// Copyright (c) 2018 Politecnico di Torino
>> +#define MAP_TYPE BPF_MAP_TYPE_QUEUE
>> +#include "test_queue_stack_map.h"
>> diff --git a/tools/testing/selftests/bpf/test_queue_stack_map.h b/tools/testing/selftests/bpf/test_queue_stack_map.h
>> new file mode 100644
>> index 000000000000..295b9b3bc5c7
>> --- /dev/null
>> +++ b/tools/testing/selftests/bpf/test_queue_stack_map.h
>> @@ -0,0 +1,59 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +// Copyright (c) 2018 Politecnico di Torino
>> +#include <stddef.h>
>> +#include <string.h>
>> +#include <linux/bpf.h>
>> +#include <linux/if_ether.h>
>> +#include <linux/ip.h>
>> +#include <linux/pkt_cls.h>
>> +#include "bpf_helpers.h"
>> +
>> +int _version SEC("version") = 1;
>> +
>> +struct bpf_map_def __attribute__ ((section("maps"), used)) map_in = {
>> + .type = MAP_TYPE,
>> + .key_size = 0,
>> + .value_size = sizeof(__u32),
>> + .max_entries = 32,
>> + .map_flags = 0,
>> +};
>> +
>> +struct bpf_map_def __attribute__ ((section("maps"), used)) map_out = {
>> + .type = MAP_TYPE,
>> + .key_size = 0,
>> + .value_size = sizeof(__u32),
>> + .max_entries = 32,
>> + .map_flags = 0,
>> +};
>> +
>> +SEC("test")
>> +int _test(struct __sk_buff *skb)
>> +{
>> + void *data_end = (void *)(long)skb->data_end;
>> + void *data = (void *)(long)skb->data;
>> + struct ethhdr *eth = (struct ethhdr *)(data);
>> + __u32 value;
>> + int err;
>> +
>> + if (eth + 1 > data_end)
>> + return TC_ACT_SHOT;
>> +
>> + struct iphdr *iph = (struct iphdr *)(eth + 1);
>> +
>> + if (iph + 1 > data_end)
>> + return TC_ACT_SHOT;
>> +
>> + err = bpf_map_pop_elem(&map_in, &value);
>> + if (err)
>> + return TC_ACT_SHOT;
>> +
>> + iph->daddr = value;
>> +
>> + err = bpf_map_push_elem(&map_out, &iph->saddr, 0);
>> + if (err)
>> + return TC_ACT_SHOT;
>> +
>> + return TC_ACT_OK;
>> +}
>> +
>> +char _license[] SEC("license") = "GPL";
>> diff --git a/tools/testing/selftests/bpf/test_stack_map.c b/tools/testing/selftests/bpf/test_stack_map.c
>> new file mode 100644
>> index 000000000000..31c3880e6da0
>> --- /dev/null
>> +++ b/tools/testing/selftests/bpf/test_stack_map.c
>> @@ -0,0 +1,4 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +// Copyright (c) 2018 Politecnico di Torino
>> +#define MAP_TYPE BPF_MAP_TYPE_STACK
>> +#include "test_queue_stack_map.h"
>>