1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
linux/tools/testing/selftests/bpf/progs/test_ringbuf_write.c
Daniel Borkmann 316930d06b selftests/bpf: Add more ring buffer test coverage
Add test coverage for reservations beyond the ring buffer size in order
to validate that bpf_ringbuf_reserve() rejects the request with NULL, all
other ring buffer tests keep passing as well:

  # ./vmtest.sh -- ./test_progs -t ringbuf
  [...]
  ./test_progs -t ringbuf
  [    1.165434] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.165825] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  [    1.284001] tsc: Refined TSC clocksource calibration: 3407.982 MHz
  [    1.286871] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x311fc34e357, max_idle_ns: 440795379773 ns
  [    1.289555] clocksource: Switched to clocksource tsc
  #274/1   ringbuf/ringbuf:OK
  #274/2   ringbuf/ringbuf_n:OK
  #274/3   ringbuf/ringbuf_map_key:OK
  #274/4   ringbuf/ringbuf_write:OK
  #274     ringbuf:OK
  #275     ringbuf_multi:OK
  [...]

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
[ Test fixups for getting BPF CI back to work ]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240621140828.18238-2-daniel@iogearbox.net
2024-06-24 13:43:55 +02:00

46 lines
939 B
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
char _license[] SEC("license") = "GPL";
struct {
__uint(type, BPF_MAP_TYPE_RINGBUF);
} ringbuf SEC(".maps");
/* inputs */
int pid = 0;
/* outputs */
long passed = 0;
long discarded = 0;
SEC("fentry/" SYS_PREFIX "sys_getpgid")
int test_ringbuf_write(void *ctx)
{
int *foo, cur_pid = bpf_get_current_pid_tgid() >> 32;
void *sample1, *sample2;
if (cur_pid != pid)
return 0;
sample1 = bpf_ringbuf_reserve(&ringbuf, 0x3000, 0);
if (!sample1)
return 0;
/* first one can pass */
sample2 = bpf_ringbuf_reserve(&ringbuf, 0x3000, 0);
if (!sample2) {
bpf_ringbuf_discard(sample1, 0);
__sync_fetch_and_add(&discarded, 1);
return 0;
}
/* second one must not */
__sync_fetch_and_add(&passed, 1);
foo = sample2 + 4084;
*foo = 256;
bpf_ringbuf_discard(sample1, 0);
bpf_ringbuf_discard(sample2, 0);
return 0;
}