diff mbox series

[bpf-next,v3,10/11] selftests/bpf: add hashmap test for bpf_for_each_map_elem() helper

Message ID 20210225073320.4121679-1-yhs@fb.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series bpf: add bpf_for_each_map_elem() helper | expand

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Commit Message

Yonghong Song Feb. 25, 2021, 7:33 a.m. UTC 
A test case is added for hashmap and percpu hashmap. The test
also exercises nested bpf_for_each_map_elem() calls like
    bpf_prog:
      bpf_for_each_map_elem(func1)
    func1:
      bpf_for_each_map_elem(func2)
    func2:

  $ ./test_progs -n 45
  #45/1 hash_map:OK
  #45 for_each:OK
  Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Yonghong Song <yhs@fb.com>
---
 .../selftests/bpf/prog_tests/for_each.c       | 74 +++++++++++++++
 .../bpf/progs/for_each_hash_map_elem.c        | 95 +++++++++++++++++++
 2 files changed, 169 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/for_each.c
 create mode 100644 tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c

Comments

Andrii Nakryiko Feb. 25, 2021, 11:25 p.m. UTC | #1 
On Thu, Feb 25, 2021 at 1:35 AM Yonghong Song <yhs@fb.com> wrote:
>
> A test case is added for hashmap and percpu hashmap. The test
> also exercises nested bpf_for_each_map_elem() calls like
>     bpf_prog:
>       bpf_for_each_map_elem(func1)
>     func1:
>       bpf_for_each_map_elem(func2)
>     func2:
>
>   $ ./test_progs -n 45
>   #45/1 hash_map:OK
>   #45 for_each:OK
>   Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED
>
> Signed-off-by: Yonghong Song <yhs@fb.com>
> ---

I think I'll just add all the variants of ASSERT_XXX and will enforce
their use :)

For now:

Acked-by: Andrii Nakryiko <andrii@kernel.org>

>  .../selftests/bpf/prog_tests/for_each.c       | 74 +++++++++++++++
>  .../bpf/progs/for_each_hash_map_elem.c        | 95 +++++++++++++++++++
>  2 files changed, 169 insertions(+)
>  create mode 100644 tools/testing/selftests/bpf/prog_tests/for_each.c
>  create mode 100644 tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c
>

[...]

> +
> +       ASSERT_EQ(skel->bss->hashmap_output, 4, "hashmap_output");
> +       ASSERT_EQ(skel->bss->hashmap_elems, max_entries, "hashmap_elems");
> +
> +       key = 1;
> +       err = bpf_map_lookup_elem(hashmap_fd, &key, &val);
> +       ASSERT_ERR(err, "hashmap_lookup");
> +
> +       ASSERT_EQ(skel->bss->percpu_called, 1, "percpu_called");
> +       ASSERT_EQ(skel->bss->cpu < num_cpus, 1, "num_cpus");

well, this is cheating (it will print something like "0 != 1" on
error) :) why didn't you just add ASSERT_LT?

> +       ASSERT_EQ(skel->bss->percpu_map_elems, 1, "percpu_map_elems");
> +       ASSERT_EQ(skel->bss->percpu_key, 1, "percpu_key");
> +       ASSERT_EQ(skel->bss->percpu_val, skel->bss->cpu + 1, "percpu_val");
> +       ASSERT_EQ(skel->bss->percpu_output, 100, "percpu_output");
> +out:
> +       free(percpu_valbuf);
> +       for_each_hash_map_elem__destroy(skel);
> +}
> +
> +void test_for_each(void)
> +{
> +       if (test__start_subtest("hash_map"))
> +               test_hash_map();
> +}

[...]

> +int hashmap_output = 0;
> +int hashmap_elems = 0;
> +int percpu_map_elems = 0;
> +
> +SEC("classifier/")

nit: just "classifier" didn't work?

> +int test_pkt_access(struct __sk_buff *skb)
> +{
> +       struct callback_ctx data;
> +
> +       data.ctx = skb;
> +       data.input = 10;
> +       data.output = 0;
> +       hashmap_elems = bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
> +       hashmap_output = data.output;
> +
> +       percpu_map_elems = bpf_for_each_map_elem(&percpu_map, check_percpu_elem,
> +                                                (void *)0, 0);
> +       return 0;
> +}
> --
> 2.24.1
>
Yonghong Song Feb. 26, 2021, 3:24 a.m. UTC | #2 
On 2/25/21 3:25 PM, Andrii Nakryiko wrote:
> On Thu, Feb 25, 2021 at 1:35 AM Yonghong Song <yhs@fb.com> wrote:
>>
>> A test case is added for hashmap and percpu hashmap. The test
>> also exercises nested bpf_for_each_map_elem() calls like
>>      bpf_prog:
>>        bpf_for_each_map_elem(func1)
>>      func1:
>>        bpf_for_each_map_elem(func2)
>>      func2:
>>
>>    $ ./test_progs -n 45
>>    #45/1 hash_map:OK
>>    #45 for_each:OK
>>    Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED
>>
>> Signed-off-by: Yonghong Song <yhs@fb.com>
>> ---
> 
> I think I'll just add all the variants of ASSERT_XXX and will enforce
> their use :)
> 
> For now:
> 
> Acked-by: Andrii Nakryiko <andrii@kernel.org>
> 
>>   .../selftests/bpf/prog_tests/for_each.c       | 74 +++++++++++++++
>>   .../bpf/progs/for_each_hash_map_elem.c        | 95 +++++++++++++++++++
>>   2 files changed, 169 insertions(+)
>>   create mode 100644 tools/testing/selftests/bpf/prog_tests/for_each.c
>>   create mode 100644 tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c
>>
> 
> [...]
> 
>> +
>> +       ASSERT_EQ(skel->bss->hashmap_output, 4, "hashmap_output");
>> +       ASSERT_EQ(skel->bss->hashmap_elems, max_entries, "hashmap_elems");
>> +
>> +       key = 1;
>> +       err = bpf_map_lookup_elem(hashmap_fd, &key, &val);
>> +       ASSERT_ERR(err, "hashmap_lookup");
>> +
>> +       ASSERT_EQ(skel->bss->percpu_called, 1, "percpu_called");
>> +       ASSERT_EQ(skel->bss->cpu < num_cpus, 1, "num_cpus");
> 
> well, this is cheating (it will print something like "0 != 1" on
> error) :) why didn't you just add ASSERT_LT?
> 
>> +       ASSERT_EQ(skel->bss->percpu_map_elems, 1, "percpu_map_elems");
>> +       ASSERT_EQ(skel->bss->percpu_key, 1, "percpu_key");
>> +       ASSERT_EQ(skel->bss->percpu_val, skel->bss->cpu + 1, "percpu_val");
>> +       ASSERT_EQ(skel->bss->percpu_output, 100, "percpu_output");
>> +out:
>> +       free(percpu_valbuf);
>> +       for_each_hash_map_elem__destroy(skel);
>> +}
>> +
>> +void test_for_each(void)
>> +{
>> +       if (test__start_subtest("hash_map"))
>> +               test_hash_map();
>> +}
> 
> [...]
> 
>> +int hashmap_output = 0;
>> +int hashmap_elems = 0;
>> +int percpu_map_elems = 0;
>> +
>> +SEC("classifier/")
> 
> nit: just "classifier" didn't work?

from libbpf.c, I think it should work. Will remove "/"
if it does work!

> 
>> +int test_pkt_access(struct __sk_buff *skb)
>> +{
>> +       struct callback_ctx data;
>> +
>> +       data.ctx = skb;
>> +       data.input = 10;
>> +       data.output = 0;
>> +       hashmap_elems = bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
>> +       hashmap_output = data.output;
>> +
>> +       percpu_map_elems = bpf_for_each_map_elem(&percpu_map, check_percpu_elem,
>> +                                                (void *)0, 0);
>> +       return 0;
>> +}
>> --
>> 2.24.1
>>
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/for_each.c b/tools/testing/selftests/bpf/prog_tests/for_each.c
new file mode 100644
index 000000000000..aa0c23e83ab8
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/for_each.c
@@ -0,0 +1,74 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include <test_progs.h>
+#include <network_helpers.h>
+#include "for_each_hash_map_elem.skel.h"
+
+static unsigned int duration;
+
+static void test_hash_map(void)
+{
+	int i, err, hashmap_fd, max_entries, percpu_map_fd;
+	struct for_each_hash_map_elem *skel;
+	__u64 *percpu_valbuf = NULL;
+	__u32 key, num_cpus, retval;
+	__u64 val;
+
+	skel = for_each_hash_map_elem__open_and_load();
+	if (CHECK(!skel, "for_each_hash_map_elem__open_and_load",
+		  "skeleton open_and_load failed\n"))
+		return;
+
+	hashmap_fd = bpf_map__fd(skel->maps.hashmap);
+	max_entries = bpf_map__max_entries(skel->maps.hashmap);
+	for (i = 0; i < max_entries; i++) {
+		key = i;
+		val = i + 1;
+		err = bpf_map_update_elem(hashmap_fd, &key, &val, BPF_ANY);
+		if (CHECK(err, "map_update", "map_update failed\n"))
+			goto out;
+	}
+
+	num_cpus = bpf_num_possible_cpus();
+	percpu_map_fd = bpf_map__fd(skel->maps.percpu_map);
+	percpu_valbuf = malloc(sizeof(__u64) * num_cpus);
+	if (!ASSERT_OK_PTR(percpu_valbuf, "percpu_valbuf"))
+		goto out;
+
+	key = 1;
+	for (i = 0; i < num_cpus; i++)
+		percpu_valbuf[i] = i + 1;
+	err = bpf_map_update_elem(percpu_map_fd, &key, percpu_valbuf, BPF_ANY);
+	if (CHECK(err, "percpu_map_update", "map_update failed\n"))
+		goto out;
+
+	err = bpf_prog_test_run(bpf_program__fd(skel->progs.test_pkt_access),
+				1, &pkt_v4, sizeof(pkt_v4), NULL, NULL,
+				&retval, &duration);
+	if (CHECK(err || retval, "ipv4", "err %d errno %d retval %d\n",
+		  err, errno, retval))
+		goto out;
+
+	ASSERT_EQ(skel->bss->hashmap_output, 4, "hashmap_output");
+	ASSERT_EQ(skel->bss->hashmap_elems, max_entries, "hashmap_elems");
+
+	key = 1;
+	err = bpf_map_lookup_elem(hashmap_fd, &key, &val);
+	ASSERT_ERR(err, "hashmap_lookup");
+
+	ASSERT_EQ(skel->bss->percpu_called, 1, "percpu_called");
+	ASSERT_EQ(skel->bss->cpu < num_cpus, 1, "num_cpus");
+	ASSERT_EQ(skel->bss->percpu_map_elems, 1, "percpu_map_elems");
+	ASSERT_EQ(skel->bss->percpu_key, 1, "percpu_key");
+	ASSERT_EQ(skel->bss->percpu_val, skel->bss->cpu + 1, "percpu_val");
+	ASSERT_EQ(skel->bss->percpu_output, 100, "percpu_output");
+out:
+	free(percpu_valbuf);
+	for_each_hash_map_elem__destroy(skel);
+}
+
+void test_for_each(void)
+{
+	if (test__start_subtest("hash_map"))
+		test_hash_map();
+}
diff --git a/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c b/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c
new file mode 100644
index 000000000000..e47e68d7a769
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/for_each_hash_map_elem.c
@@ -0,0 +1,95 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2021 Facebook */
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+struct {
+	__uint(type, BPF_MAP_TYPE_HASH);
+	__uint(max_entries, 3);
+	__type(key, __u32);
+	__type(value, __u64);
+} hashmap SEC(".maps");
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
+	__uint(max_entries, 1);
+	__type(key, __u32);
+	__type(value, __u64);
+} percpu_map SEC(".maps");
+
+struct callback_ctx {
+	struct __sk_buff *ctx;
+	int input;
+	int output;
+};
+
+static __u64
+check_hash_elem(struct bpf_map *map, __u32 *key, __u64 *val,
+		struct callback_ctx *data)
+{
+	struct __sk_buff *skb = data->ctx;
+	__u32 k;
+	__u64 v;
+
+	if (skb) {
+		k = *key;
+		v = *val;
+		if (skb->len == 10000 && k == 10 && v == 10)
+			data->output = 3; /* impossible path */
+		else
+			data->output = 4;
+	} else {
+		data->output = data->input;
+		bpf_map_delete_elem(map, key);
+	}
+
+	return 0;
+}
+
+__u32 cpu = 0;
+__u32 percpu_called = 0;
+__u32 percpu_key = 0;
+__u64 percpu_val = 0;
+int percpu_output = 0;
+
+static __u64
+check_percpu_elem(struct bpf_map *map, __u32 *key, __u64 *val,
+		  struct callback_ctx *unused)
+{
+	struct callback_ctx data;
+
+	percpu_called++;
+	cpu = bpf_get_smp_processor_id();
+	percpu_key = *key;
+	percpu_val = *val;
+
+	data.ctx = 0;
+	data.input = 100;
+	data.output = 0;
+	bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
+	percpu_output = data.output;
+
+	return 0;
+}
+
+int hashmap_output = 0;
+int hashmap_elems = 0;
+int percpu_map_elems = 0;
+
+SEC("classifier/")
+int test_pkt_access(struct __sk_buff *skb)
+{
+	struct callback_ctx data;
+
+	data.ctx = skb;
+	data.input = 10;
+	data.output = 0;
+	hashmap_elems = bpf_for_each_map_elem(&hashmap, check_hash_elem, &data, 0);
+	hashmap_output = data.output;
+
+	percpu_map_elems = bpf_for_each_map_elem(&percpu_map, check_percpu_elem,
+						 (void *)0, 0);
+	return 0;
+}