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Partially revert bpf: Zero-fill re-used per-cpu map element

Drop the added selftest as it depends on functionality that doesn't
exist in 5.4.

Signed-off-by: Sasha Levin <sashal@kernel.org>
5.4-rM2-2.2.x-imx-squashed
Sasha Levin 2020-12-08 09:52:46 -05:00 committed by Greg Kroah-Hartman
parent 512b18eec5
commit 4a77729b25
2 changed files with 0 additions and 247 deletions

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@ -1,214 +0,0 @@
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2020 Tessares SA <http://www.tessares.net> */
#include <test_progs.h>
#include "test_map_init.skel.h"
#define TEST_VALUE 0x1234
#define FILL_VALUE 0xdeadbeef
static int nr_cpus;
static int duration;
typedef unsigned long long map_key_t;
typedef unsigned long long map_value_t;
typedef struct {
map_value_t v; /* padding */
} __bpf_percpu_val_align pcpu_map_value_t;
static int map_populate(int map_fd, int num)
{
pcpu_map_value_t value[nr_cpus];
int i, err;
map_key_t key;
for (i = 0; i < nr_cpus; i++)
bpf_percpu(value, i) = FILL_VALUE;
for (key = 1; key <= num; key++) {
err = bpf_map_update_elem(map_fd, &key, value, BPF_NOEXIST);
if (!ASSERT_OK(err, "bpf_map_update_elem"))
return -1;
}
return 0;
}
static struct test_map_init *setup(enum bpf_map_type map_type, int map_sz,
int *map_fd, int populate)
{
struct test_map_init *skel;
int err;
skel = test_map_init__open();
if (!ASSERT_OK_PTR(skel, "skel_open"))
return NULL;
err = bpf_map__set_type(skel->maps.hashmap1, map_type);
if (!ASSERT_OK(err, "bpf_map__set_type"))
goto error;
err = bpf_map__set_max_entries(skel->maps.hashmap1, map_sz);
if (!ASSERT_OK(err, "bpf_map__set_max_entries"))
goto error;
err = test_map_init__load(skel);
if (!ASSERT_OK(err, "skel_load"))
goto error;
*map_fd = bpf_map__fd(skel->maps.hashmap1);
if (CHECK(*map_fd < 0, "bpf_map__fd", "failed\n"))
goto error;
err = map_populate(*map_fd, populate);
if (!ASSERT_OK(err, "map_populate"))
goto error_map;
return skel;
error_map:
close(*map_fd);
error:
test_map_init__destroy(skel);
return NULL;
}
/* executes bpf program that updates map with key, value */
static int prog_run_insert_elem(struct test_map_init *skel, map_key_t key,
map_value_t value)
{
struct test_map_init__bss *bss;
bss = skel->bss;
bss->inKey = key;
bss->inValue = value;
bss->inPid = getpid();
if (!ASSERT_OK(test_map_init__attach(skel), "skel_attach"))
return -1;
/* Let tracepoint trigger */
syscall(__NR_getpgid);
test_map_init__detach(skel);
return 0;
}
static int check_values_one_cpu(pcpu_map_value_t *value, map_value_t expected)
{
int i, nzCnt = 0;
map_value_t val;
for (i = 0; i < nr_cpus; i++) {
val = bpf_percpu(value, i);
if (val) {
if (CHECK(val != expected, "map value",
"unexpected for cpu %d: 0x%llx\n", i, val))
return -1;
nzCnt++;
}
}
if (CHECK(nzCnt != 1, "map value", "set for %d CPUs instead of 1!\n",
nzCnt))
return -1;
return 0;
}
/* Add key=1 elem with values set for all CPUs
* Delete elem key=1
* Run bpf prog that inserts new key=1 elem with value=0x1234
* (bpf prog can only set value for current CPU)
* Lookup Key=1 and check value is as expected for all CPUs:
* value set by bpf prog for one CPU, 0 for all others
*/
static void test_pcpu_map_init(void)
{
pcpu_map_value_t value[nr_cpus];
struct test_map_init *skel;
int map_fd, err;
map_key_t key;
/* max 1 elem in map so insertion is forced to reuse freed entry */
skel = setup(BPF_MAP_TYPE_PERCPU_HASH, 1, &map_fd, 1);
if (!ASSERT_OK_PTR(skel, "prog_setup"))
return;
/* delete element so the entry can be re-used*/
key = 1;
err = bpf_map_delete_elem(map_fd, &key);
if (!ASSERT_OK(err, "bpf_map_delete_elem"))
goto cleanup;
/* run bpf prog that inserts new elem, re-using the slot just freed */
err = prog_run_insert_elem(skel, key, TEST_VALUE);
if (!ASSERT_OK(err, "prog_run_insert_elem"))
goto cleanup;
/* check that key=1 was re-created by bpf prog */
err = bpf_map_lookup_elem(map_fd, &key, value);
if (!ASSERT_OK(err, "bpf_map_lookup_elem"))
goto cleanup;
/* and has expected values */
check_values_one_cpu(value, TEST_VALUE);
cleanup:
test_map_init__destroy(skel);
}
/* Add key=1 and key=2 elems with values set for all CPUs
* Run bpf prog that inserts new key=3 elem
* (only for current cpu; other cpus should have initial value = 0)
* Lookup Key=1 and check value is as expected for all CPUs
*/
static void test_pcpu_lru_map_init(void)
{
pcpu_map_value_t value[nr_cpus];
struct test_map_init *skel;
int map_fd, err;
map_key_t key;
/* Set up LRU map with 2 elements, values filled for all CPUs.
* With these 2 elements, the LRU map is full
*/
skel = setup(BPF_MAP_TYPE_LRU_PERCPU_HASH, 2, &map_fd, 2);
if (!ASSERT_OK_PTR(skel, "prog_setup"))
return;
/* run bpf prog that inserts new key=3 element, re-using LRU slot */
key = 3;
err = prog_run_insert_elem(skel, key, TEST_VALUE);
if (!ASSERT_OK(err, "prog_run_insert_elem"))
goto cleanup;
/* check that key=3 replaced one of earlier elements */
err = bpf_map_lookup_elem(map_fd, &key, value);
if (!ASSERT_OK(err, "bpf_map_lookup_elem"))
goto cleanup;
/* and has expected values */
check_values_one_cpu(value, TEST_VALUE);
cleanup:
test_map_init__destroy(skel);
}
void test_map_init(void)
{
nr_cpus = bpf_num_possible_cpus();
if (nr_cpus <= 1) {
printf("%s:SKIP: >1 cpu needed for this test\n", __func__);
test__skip();
return;
}
if (test__start_subtest("pcpu_map_init"))
test_pcpu_map_init();
if (test__start_subtest("pcpu_lru_map_init"))
test_pcpu_lru_map_init();
}

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@ -1,33 +0,0 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Tessares SA <http://www.tessares.net> */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
__u64 inKey = 0;
__u64 inValue = 0;
__u32 inPid = 0;
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
__uint(max_entries, 2);
__type(key, __u64);
__type(value, __u64);
} hashmap1 SEC(".maps");
SEC("tp/syscalls/sys_enter_getpgid")
int sysenter_getpgid(const void *ctx)
{
/* Just do it for once, when called from our own test prog. This
* ensures the map value is only updated for a single CPU.
*/
int cur_pid = bpf_get_current_pid_tgid() >> 32;
if (cur_pid == inPid)
bpf_map_update_elem(&hashmap1, &inKey, &inValue, BPF_NOEXIST);
return 0;
}
char _license[] SEC("license") = "GPL";